'Aliah's Musculoskeletal System & Head & Neck

THE BONES OF THE LOWER LIMB

PORTION DETAILS

OVERVIEW

Lower limbs r extension from e trunk specialized for:1. Body weight support.2. Locomotion.3. Maintenance of balance.

Mechanism of weight bearing: Trunk (vertebral column) → sacroiliac joints → pelvic

girdle → hip joints → femurs → knee joints → tibia → ankle joints → talus.

E regions of lower limbs:1. Hip joint (pelvic girdle).2. Femur.3. Tibia & fibula. 4. Foot.

HIP BONES E mature hip bone is: large, flat pelvic bone formed by e fusion of 3 primary bones which r ilium, ischium, & pubis. Pelvic girdle: a bony ring composed of sacrum & Rt. & Lt. hip bones joined anteriorly at e pubic symphysis. Functions: support & protect e abdomen, pelvis, perineum, & lower limb.

ILIUM

E largest hip bone (2/5 distribution) & e most superior part of acetabulum. Parts of ilium:

1. E columns: thick medial portions for weight bearing.2. E wings or alae: thin, wing-like, & posterolateral portions for fleshy attachment.

E iliac fossa: large & smooth depression which provides attachment for e iliac muscle. 3. E body: joins e pubis & ischium to form acetabulum.4. E iliac crest:

Long, curved, & thickened superior border of e ala of e ilium which extends posteriorly & begins at ASIS & ends at PSIS.

Functions:a. Serves as protective bumper.b. Important part of aponeurotic attachment for thin, sheet-like muscle & deep fascia.

5. E tubercle of e iliac crest: a prominence on e external lip of e crest which lies 5-6 cm posterior to e ASIS.

6. E spines: provide attachment for ligaments & tendons of lower limb muscles.a. Anterior superior & inferior iliac spines.b. Posterior superior & inferior iliac spines (marks e superior end of e greater sciatic

notch).7. E gluteal region: e lateral surface of ala that has 3 rough curved lines, i.e. e posterior,

anterior, & inferior gluteal lines which demarcate e proximal attachments of e 3 large glutei.

8. E auricular surface: a rough, ear-shaped articular area which is located at e medial aspect of posterior ilium.

9. Iliac tuberosity: rough surface area of posterior ilium which is superior to e auricular surface for synovial & syndesmotic articulation with e reciprocal surfaces of e sacrum at e sacroiliac joint.

ISCHIUM

Forms e posteroinferior part of e hip bone with 2/ distribution of hip bone. Parts of ischium:

1. E body of ischium: its superior part fuses with e pubis & ilium forming e posteroinferior aspect of acetabulum.

2. E ramus of e ischium: joins e inferior ramus of e pubis to form e ischiopubic ramus which constitutes e inferomedial boundary of e obturator foramen.

3. E greater sciatic notch (GSN): a deep indentation whose inferior margin is formed by e posterior border of e ischium.

4. Ischial spine: A large & triangular spine at e inferior margin of e GSN which provides a ligamentous

attachment. Separates e GSN from a > inferior, smaller, rounded, & smooth surfaced indentation of

lesser sciatic notch.5. E lesser sciatic notch: serves as a trochlea or pulley for a muscle that emerges from e bony

pelvis.6. E ischial tuberosity:

E rough bony projection at e junction of e inferior end of e body of ischium & its ramus. Functions:

a. Weight bearing during sitting position.b. Provides e proximal, tendinous attachment of posterior thigh muscle.

PUBIS

Forms e anteromedial part of e hip bone, contributes e anterior part of e acetabulum, & provides proximal attachment for muscles of e medial thigh.

Parts of pubis:1. E rami of e pubis: inferior & superior rami which r strong & maintain e arch composed of e

sacrum & e 2 ilia by which axial weight is divided & transferred laterally to e limbs when standing & to e ischial tuberosity when sitting.

2. E body of pubis: medially, its symphysial surface articulates with e corresponding surface of e pubis of e contralateral pubis by means of e pubic syhmphysis.

3. E pubic crest: located at e anterosuperior border of e united bodies & symphysis pubis which provides attachment for abdominal muscles.

4. E pubic tubercles: a small projection at e lateral ends of e pubic crest which is an important landmark of e inguinal region.

5. E pectin pubis: a sharp, raised edge at e posterior margin of e superior ramus of pubis.

ACETABULUM Is e large cup shaped cavity or socket on e lateral aspect of e hip bone.

Articulates with e head of femur to form e hip joint. Its margin is incomplete inferiorly at e acetabular notch which makes fossa resemble a piece

of its lip missing. Acertabular fossa: e rough depression in e floor of acetabulum extending superiorly from e

acetabular notch. A acetabular notch & fossa create a deficit in e smooth lunate surface of e acetabulum which

articulates with e head of e femur.

OBTURATOR FORAMEN

A large oval or irregularly triangular aperture in e hip bone. Bounded by e pubis & ischium & their rami. Closed by e thin obturator membrane except for a small passageway of obturatoe nerve &

vessels. E presence of foramen minimizes bony mass. Its closure by obturator membrane provides extensive surface area on both sides for fleshy

muscle attachment.

FEMUR E longest & heaviest bone in e body. Its length = ¼ height. Function: transmits body weight from e hip bone to e tibia when a person is standing. Parts of femur:

1. E proximal end: Head:

Round shaped bone which makes up 2/3 of a sphere that is covered with articular cartilage. Has e medially placed depression or pit called fovea capitis which is not covered by articular cartilage &

provides attachment for round ligament of e femoral head. Neck:

Trapezoidal in shape with its narrow end supporting e head & its broader base being continuous with e shaft.

Its average diameter is ¾ that of femoral head. 2 trochanters (large & blunt elevation):

a. E greater trochanter: a large, laterally placed bony mass that projects superiorly & posteriorly where e neck joins e femoral shaft providing attachment & leverage for abductors & rotators of e thigh. In anterior & posterior view, it is in line with e femoral shaft. It also overhangs a deep depression medially e trochanteric fossa.

b. E lesser trochanter: an abrupt, conical, & rounded in shaped elevation which extends medially from e posteromedial part of e junction of e neck & shaft to give tendinous attachment to e primary flexor of e thigh (e iliopsoas).

E intertrochanteric lines: A roughened ridge formed by e attachment of iliofemoral ligament that runs anteriorly from e greater

trochanter to e lesser one. Indicates e site where e neck & shaft join. Winds around e lesser trochanter to continue posteriorly & inferiorly as a less distinct ridge, e spiral line.

E intertrochanteric crest: a smoother & > prominent ridge which joins e trochanters posteriorly. E quadrate tubercle: e rounded elevation one crest. E angle of inclination:

Allows greater mobility of e femur at e hip joint because it places e head & neck > perpendicular to e acetabulum in e neutral position.

Allows e obliquity of e femur within e thigh. E torsion angle or e angle of declination: combines with e angle of inclination, allows rotator movements of e

femoral head within e obliquely placed acetabulum to convert into flexion & extension, abduction & adduction, & rotational movements of e thigh.

2. E shaft: E shaft is slightly bowed anteriorly, most r smoothly rounded, providing fleshing origin to extensors of e

knee. E linea aspera:

A broad & rough line which provides aponeurotic attachment for adductors of e thigh. Is prominent in e middle third of e femoral shaft, where it has medial & lateral lips. Superiorly, e lateral lip blends with e broad & rough gluteal tuberosity. E medial lip continues as a narrow & rough spiral line which is continues with intertrochanteric line

proximally. E pectineal line: a prominent intermediate ridge which extends from e central part of linea aspera to e

base of lesser trochanter. Inferiorly, linea aspera divides into medial & lateral supracondylar lines which lead to e spirally curved

medial & lateral condyles.3. E distal end:

E medial & lateral femoral condyles make up e entire inferior end of femur. E condyles r on e same horizontal level when e bone is in its anatomical position. E femoral condyles articulate with menisci & tibial condyles to form e knee joint. E condyles r separated posteriorly & inferiorly by an intercondylar fossa but merge anteriorly, forming a

shallow longitudinal depression, e patellar surface which articulates with e patella. Lateral epicondyle: a central projection on e lateral surface of e lateral condyle. Provide proximal

attachment for e collateral Medial epicondyle: a larger & > prominent projection on e medial condyles. ligaments of

e knee joint. Adductor tubercle: an alevation superior to medial epicondyle for tendonous attachment.

TIBIA A 2nd largest bone which is located on e anteromedial side of e leg, nearly parallel to e fibula.

It flares outward at both end to provide an increased area for articulation & weight transfer. E superior end widens to form medial & lateral epicondyles. E tibial plateau or flat superior articular surface:

Consists of 2 smooth articular surfaces that articulate with e large condyles of femur & separated by an intercondylar eminence formed by 2 intercondylar tubercles.

Intercondylar tubercles: Flanked by relatively rough anterior & posterior intercondylar areas. Fit into e fossa b/w femoral condyles. Provide attachment for e menisci & principal ligaments of e knee which hold e femur & tibia together,

maintaining contact b/w their articular sufaces. E lateral tibial condyle:

Its anterolateral aspect bears an anterolateral tibial tubercle inferior to e articular surface which provides e distal attachment for a dense thickening of e fascia covering e lateral thigh, adding stability to knee joint.

Bears a fibular articular facet posterolaterally on its inferior aspect for e head of fibula. E shaft of e tibia:

Truly vertical within e leg & triangular in cross section with 3 surfaces & borders: medial, lateral/ interosseous, & posterior border.

E shaft is thinnest at e junction of its middle & distal 3rd. E anterior border of tibia is e most prominent border because it is subcutaneous & known as shin bone which is

vunerable to bruising. E interosseous border of tibia is sharp where it gives attachment to e interosseous membrane that unites e 2 leg

bones. E distal end of tibia:

Smaller than proximal end, flaring only medially & e medial expansion extends inferior to e rest of e shaft as e medial malleolus which articulates with e talus together with e lateral surface. This is covered with articular cartilage.

E fibular notch: a groove which replaces e sharp border & provides fibrous attachment to e distal end of e fibula. Soleal line: a rough diagonal ridge located on e posterior surface of e proximal part of e tibial shaft which runs

inferomedially to e medial border for aponeurotic origin of e soleus muscle. Nutrient foramen: from it, an obliquely directed vascular groove (nutrient canal) runs inferiorly in e tibia before it

opens into e medullary (marrow) cavity.

FIBULA A slender bone which lies posterolaterally to e tibia & is firmly attached to it by e tibiofibular syndesmosis (includes

e interosseus membrane). Has no function in weight bearing, mainly serves for muscle attachment (1 insertion & 8 origins). E fibers of e tibiofibular syndesmosis r arranged to resist e resulting net downward pull on e fibula. E distal end enlarges & is prolonged laterally & inferiorly as e lateral malleolus which is > prominent & posterior

than e medial malleolus & extends ~ 1 cm > distally. E proximal end consists of:

1. An enlarged head: Has a pointed apex form in r/ship to a tendinous attachment. Articulates with e fibular facet on e posterolateral & inferior aspect of e lateral tibial condyle.

2. A smaller neck. E shaft of fibula:

Is twisted & marked by e sites of muscular attachment. It is triangular in cross section. Has 3 borders (anterior, interosseous, & posterior) & 3 surfaces (medial, posterior, & lateral).

FOOT1. Tarsus:

a. Talus: Has a body, neck, & head. Head: rounded anterior end with large facet for articulation with e navicular bone, one articulation with e

sustentaculum tali of e calcaneus, & a small articulation with e plantar calcaneonavicular ligament (spring ligament).

Neck: e slightly constricted part b/w e head & body where sulcus talum (deep grove) is located for e ligament connecting e talus & calcaneus.

Body: its inferior part articulates with e calcaneus. Its also has a posterior surface that has medial & lateral tubercle where in b/w them there is a groove for flexor hollucis longus muscle.

Identification: rounded head interiorly, trochlear surface of body superiorly, lateral triangular feet, & medial comma-shaped facet.

E only tarsal bone which has no muscular or tendinous attachment & most of its surface is covered by articular cartilage.

E most proximal of tarsal bone rests on e anterior 2/3 of e calcaneus & articulates with e malleoli to form e ankle mortise joint. It also articulates with navicular bone.

Superior surface of e talus bears e body weight transmitted via tibia. b. Calcaneus:

E heel bone which is e largest & strongest bone in e foot. Transmits majority of e body weight from talus to e ground. Articulates with e talus superiorly & e cuboid anteriorly. Identification:

Anterior end: smaller & aricular. Posterior end: larger & roughened. Inferior surface: calcaneum tuberosity, medial & lateral surface. Medial surface: concave & has sustentacular tali which supports e talar head. Lateral surface: peroneal tubercle or fibular trochlea which anchors a tendon pulley for e evertors of e

foots.c. Navicular:

A flattened & boat shaped bone located b/w e talar head posteriorly & e cuneiforms anteriorly. It articulates with e head of talus & all 3 cuneiform bones.its medial surface projects inferiorly to form e

navicular tuberosity that is important for tibialis posterior attachment. It is also e attachment site for spring ligament that supports e medial longitudinal arch of e foot.

d. Cuboid: Approximately cubical in shape & e most lateral bone in e distal bone row of tarsus. Articulates with e calcaneus proximally & e 4th & 5th metatarsal bones distally. Anterior to e tuberosity of e cuboid on e lateral & inferior surfaces of e bone is a groove for e tendon of e

fibularis longus muscle.e. Cuneiform:

Medial cuneiform: e most medial bone in e distal row of tarsal bones. Intermediate cuneiform: e smallest cuneiform bone located b/w medial & lateral cuneiforms. Lateral cuneiform: located b/w intermediate cuneiform & cuboid bones (forms articulation). Each articulates with e navicular posteriorly & e base of its appropriate metatarsal anteriorly.

2. Metatarsus: Five metatarsal bones which r located b/w e tarsal bones & e phalanges. Base: e proximal end which articulates with e distal row of tarsal bones forming tarsometatarsal line. Body: e slender shaft of e metatarsal which is also known as diaphysis. Head: e rounded distal end of e metatarsal which articulates with e proximal phalanx of e corresponding digits. E bases of 1st & 5th metatarsals have large tuberosities that provide for tendon attachment. On e plantar surface of e head of e 1st metatarsal r prominent medial & lateral sesamoid bones which r

embedded in e tendons passing along e plantar surface.3. Phalanges:

E 14 phalanges r as follows: e 1st digit (great toe) has 2 phalanges (proximal & distal) & e other 4 digits have 3 phalanges each (proximal, middle, & distal).

Each phalanx has:a. Base: e proximal end of e phalanx. E base of e proximal phalanges articulates with e head of e

corresponding metatarsal bone while e base of e middle or distal phalanges articulates with e head of e most proximal phalanges.

b. Body: e slender shaft of e phalanx which also known as e diaphysis.c. Head: e distal end of e phalanx. E proximal, middle, & distal phalanges each have a head. E head of a

proximal & middle phalanges articulates with e base of e next most distal palanges. E phalanges of e 1st digit r short, broad, & strong. E middle & distal phalanges of 5th digit may be fused in elderly.

MUSCLES OF THE THIGH

MUSCLES ORIGIN INSERTION NERVE SUPPLY

NERVE ROOT

ACTIONS

ANTERIOR COMPARTMENT

SARTORIUS ASIS

Pes anserinus- Upper medial

surface of tibia.

Femoral nerve L2 & L3

1. Flexes, abducts, & laterally rotates thigh at hip

joint.2. Flexes & medialy

rotates leg at knee joint.

ILIACUS Iliac fossa of e ilium

Lesser trochanter of

femur

Femoral nerve L2 & L3 Flexes thigh on trunk.

PSOAS

Transverse processes,

bodies, & IV of T12 & L1 – L5

Lesser trochanter of

femur

Lumbar plexus

L1, L2, & L3 Flexes thigh on trunk.

PECTINEUS Superior ramus of pubis

Upper end of linea aspera

Femoral nerve L2 & L3 Flexes & adducts thigh at hip

joint.

RECTUS FEMORIS

1. Straight head: AIIS.

2. Reflected head: ilium

above acetabulum.

Quadriceps tendon at

patella, then via ligamentum

patelliae into tubercle of

tibia.

Femoral nerve

L2, L3, & L4

Extension of leg at knee

joint.

Quadricep

femoris

muscle.

VASTUS LATERALIS Upper end &

shaft of femurVASTUS MEDIALIS

VASTUS INTERMEDIUS

Anterior & lateral surfaces

of e shaft of femur

MEDIAL COMPARTMENTSUPERFICIAL LAYER

ADDUCTOR LONGUS

Body of pubis & medial to pubic

tubercleLinea aspera Obturator

nerve

L2, L3, & L4

Adducts thigh at hip joint & assists in lateral rotation.

GRACILISInferior ramus of pubis & ramus

of ischiumL2 & L3 Adducts thigh at hip joint & at

flexes leg at knee joint.

PECTINEUS Superior ramus of pubis Pectineal line Femoral

nerve L2 & L3 Adducts & flexes thigh & assists with medial rotation of thigh.

MIDDLE LAYER

ADDUCTOR BREVIS

Inferior ramus of pubis Linea aspera Obturator

nerveL2, L3, &

L4Adducts thigh at hip joint & assists in lateral rotation.

DEEP OR INNERMOST LAYER

ADDUCTOR MAGNUS

Inferior ramus of pubis, ramus of

ischium, & ischial

tuberosity

Linea aspera & adductor

tubercle of femur

1. Adductor:

obturator nerve.

2. Hamstring: sciatic nerve.

L2, L3, & L4

Adducts thigh at hip joint, assists in lateral rotation, & hamstring

portion extends thigh at hip joint.

OBTURATUR EXTERNUS

Outer surface of obturator

membrane & pubic & ischial

rami

Medial surface of greater trochanter

(trochanteric fossa)

Obturator nerve L3 & L4 Laterally rotates thigh at hip

joint.

POSTERIOR COMPARTMENTBICEPS

FEMORIS1. Long

head: ischial tuberosity

2. Short head: linea

aspera, lateral supracondylar

Head of fibula 1.Long head: tibial

nerve.2.Short

head: common peroneal

L5, S1, & S2

Flexes & lateraaly rotates leg at knee joint. Long head also extends thigh at hip joint.

ridge. nerve.

SEMI-TENDINOSUS

Ischial tuberosity

Upper part of medial surface of shaft of tibia Tibial nerve L5, S1, &

S2

Flexes & medially rotate leg at knee joint & extend thigh at hip

joint.SEMI-MEMBRANOSUS

Ischial tuberosity

Medial condyle of tibia

THE THIGH

PORTION DETAILS

ANTERIOR THIGH

PECTINEUS

A flat quadrangular muscle located in e anterior part of e superomedial aspect of thigh. Composed of 2 layers, superficial & deep which r innervated by 2 different nerves. Actions:

1. Adducts & flexes e thigh.2. Assists in e medial rotation of e thigh.

Because of e dual nerve supply & actions, it is actually a transitional muscle b/w e anterior & medial compartment.

ILIOPSOAS

It is relatively hidden with most of its mass located in e posterior wall of e abdomen & greater pelvis.

Composed of:1. E iliacus: broad lateral part which arises from e iliac fossa.2. E psoas major: long medial part which arises from e lumbar vertebrae.

Thus, it is e only muscle which attaches to e vertebral column, pelvis, & femur. Actions:

1. Has concentric contraction which produces flexion at e hip joint to:a. Lift e limb & initiates its forward swing during walking.b. Elevate e limb during climbing.

2. Has bilateral contraction which: a. Initiates flexion of e trunk at e hip on e fixed thigh.b. Increases e lumbar curvature of e vertebral column.

3. Has eccentric contraction that resists acceleration during walking downhill.4. Acts as a postural muscle which is active during standing in maintaining lumbar lordosis,

indirectly compensatory thoracic kyphosis, & resisting hyperextension of e hip joint.

SARTORIUS

Is e tailor’s muscle which is long & ribbon-like (longest muscle in e body). It passes obliquely across e superoanterior part of e thigh & descends inferiorly as far as e

side of e knee. Lies superficially inside e anterior compartment within its own relatively distinct fascial

sheath. It acts across 2 joints which influences its actions:

1. Flexes e hip joint. E actions of Sartorius r not strong,

2. Weakly abducts & laterally rotates e thigh. thus, it acts synergistically with

3. E actions of both Sartorius muscles lead to cross-legged sitting position. other thigh muscles.

QUADRICEPS FEMORIS

Constitutes e largest & one of e most powerful muscles in e body. It is 3x stronger than hamstring muscles & covers almost all e anterior aspect of e femur. Its actions:

1. E great extensor of e leg.2. Its concentric contraction extends e knee against gravity during rising, climbing, &

walking upstairs, & for acceleration & projection.3. Becomes active in e termination of e swing phase to prepare e knee to accept weight.4. Responsible for absorbing e jarring shock of heel strike.5. Acts as a fixator during bent-knee sports.6. Contracts eecentrically during downhill walking & descending stairs.

Composed of:1. Rectus femoris: capable of flexing e thigh at e hip joint & extending e leg at knee joint. 2. Vastus medialis: covers e medial side of e thigh.3. Vastus lateralis: e largest component of QF which lies on e lateral side of e thigh.4. Vastus intermedius: lies deep to e rectus femoris b/w e other 2 vasti.

E tendons of e 4 parts of QF unite in e distal position of e thigh to form a single, strong, & broad quadriceps tendon which becomes e ligamentum patellae & attached to e tibial tuberosity.

On e other hand, medial & lateral vasti muscles also attach independently to e patella to form aponeuroses, e medial & lateral retinacula which attach to e anterior border of e tibial plateau.

MEDIAL THIGH

SUPERFICIAL LAYER

ADDUCTOR LONGUS

A large, triangular, &fan-shaped muscle which is e most anteriorly placed of e adductor group.

Arises by a strong tendon from e anterior aspect of e body of e pubic tubercle & expands to attach to e linea aspera of e femur.

Thus, it covers e anterior aspect of adductor brevis & middle of e adductor magnus.

GRACILIS A long, strap-like muscle & is e most medial muscle of e thigh. It is e most superficial of e adductor group & e weakest member. It is e only one to cross both e knee & hip joint. Its actions:

1. It is a synergist in adducting e thigh, flexing e knee, & rotating e leg medially when e knee is flexed.

2. It acts with e other pes anserinus muscles to add stability to e medial aspect of e extended knee.

PECTINEUS Pectineus muscle can be classified both as anterior & medial compartment muscle (refer above for details).

MIDDLE LAYER

ADDUCTOR BREVIS

A short adductor which lies deep to e pectineus & adductor longus where it arises from e body & inferior ramus of pubis.

It widens as it passes distally to attach to e linea aspera. It is located in b/w e anterior & posterior divisions of obturator nerve.

DEEPEST LAYER

ADDUCTOR MAGNUS

E largest & most posterior muscle in e adductor group which is a composite, triangular muscle with a thick, midlle margin that has an adductor part & a hamstring part (differ in attachment, nerve supply, & main actions).

E adductor part attaches along e linea aspera & extends inferiorly onto e medial supracondylar ridge.

E hamstring part has a tendinous distal attachment to e adductor tubercle.

OBTURATOR EXTERNUS

A flat, relatively small, & fan-shaped muscle which is deeply placed in e superomedial part of e thigh.

It extends from e external surface of e obturator membrane & surrounding bone of e pelvis to e posterior aspect of e greater trochanter, passing directly under e acetabulum & e neck of femur.

ACTIONS OF E ADDUCTOR

GROUP

1. Used in all movement in which e thigh r adducted.2. To stabilize e stance when standing on both feet.3. To correct lateral sway of e trunk or when there is a side-to-side shift of e surface on which

one is standing.4. Used in kicking with e medial side of e foot & in swimming.5. Contribute to flexion of e extended thigh & extension of e flexed thigh when running or

against resistance.

POSTERIOR THIGH

HAMSTRING MUSCLES

Consist of:1. Semitendinosus muscle.2. Semimembranosus muscle.3. Biceps femoris muscle (long head).

Common features:1. Proximal attachment to e ischial tuberosity deep to e gluteus maximus.2. Spanning & acting on 2 joints: extension at e hip joint & flexion at e knee.3. Innervations by e tibial division of e sciatic nerve.

E actions: 2 actions can’t be formed maximally at e same time. When e thighs & legs r fixed, they can help extend e trunk at hip joint. They r active in thigh extension under all situations including maintenance of e relaxed

standing posture except full flexion of e knee. They r hip extensors involved in walking on flat ground when e gluteus maximus acts in

minimal activity. They demonstrate most activity when they r eccentrically contracting, resisting hip

flexion & knee extension during terminal swing.

BICEPS FEMORIS

It has 2 heads:1. Long head:

Crosses & provides protection for e sciatic nerve. Innervated by e tibial branch of sciatic nerve. Its biceps tendon runs inferiorly with e lateral branch of e sciatic nerve.

2. Short head: Arises from e lateral lip of e inferior 3rd of e linea aspera & supracondylar ridge of e

femur. Innervated by e fibular division of sciatic nerve.

Different nerve supply b/w e 2 heads prevents e paralyze of both heads when one of e nerves is injured.

In e inferior part of e thigh, e long head becomes tendinous & is joined by e short head to form e rounded common tendon that attaches to e head of e fibula.

It produces 40% lateral rotation of e tibia at e knee when e knee is flexed to 90o.

SEMI-TENDINOSUS

A fusiform belly that is usually interrupted by a tendinous intersection & a long, cord-like tendon that begins ~ 2/3 of e way down e thigh.

Distally, e tendon attaches to e medial surface of e superior part of e tibia as part of pes anserinus.

SEMI-MEMBARNOSUS

A broad muscle which is has a flattened membranous part at its proximal attachment to e ischial tuberosity.

Its tendon forms around e middle of e thigh & descends to e posterior part of e tibial medial condyle.

It tendon divides distally into 3 parts:1. A direct attachment to e posterior aspect of e medial tibial condyle.2. A part that blend with e popliteal fascia.3. A reflected part that reinforces e intercondylar part of e joint capsules of e knee at e

oblique popliteal ligament.

When e knee is flexed 90o, its contraction produces ~ 10o medial rotation of tibia at e knee.

OTHER STRUCTURES

SUPERFICIAL FASCIA

Implies e subcutaneous tissue which lies deep to e skin. Consists of loose connective tissue that contains:

1. Fat, lymphatic vessels, & lymph nodes.2. Cutaneous nerve & superficial veins.

E subcutaneous tissue of e hip & thigh is continuous with that of e inferior part of e anterolateral abdominal wall & buttock.

At e knee, it loses its fat & blends with e deep fascia, but in leg, fat are again present.

FASCIA LATA

Also known as deep fascia which is strong in investing e limb like an elastic stocking. It limits e outward expansion of contracting muscle making muscular contraction > efficient in

compressing veins to push e blood towards e heart. It continues inferior to e knee as e deep fascia of e leg. It attaches to:

1. Superiorly: E inguinal ligament, pubic arch, body of pubis, & pubic tubercle.2. Laterally & posteriorly: E iliac crest.3. Posteriorly: Sacrum, coccyx, sacrotuberous ligament, & ischial tuberosity.4. Distally: E exposed part of bones around e knee & crural fascia of e leg.

It is substantial because it encloses e lateral thigh muscles. Iliotibial tract:

E thickened & strengthened part of fascia lata by additional reinforcing longitudinal fibers. It is e conjoint of e tensor of fascia lata & gluteus maximus muscle. Extends from e iliac tubercle to e anterolateral tibial tubercle.

E walls of e 3 compartments of e thigh r formed by e fascia lata & 3 fascial intermuscular septa that arise from its deep aspect & attach to e linea aspera of e femur.

SAPHENOUS OPENING

A gap or hiatus in e fascia lata inferior to e medial part of e inguinal ligament, ~ 4cm inferolateral to e pubic tubercle.

It is ~ 3.75 cm in length & 2.5 cm in breadth, & its long axis is vertical. Its margins:

1. Medial margin is smooth. Joined by fibrofatty

2. Superior, lateral, & inferior margins form a sharp, crescentic adge, e falciform fascia. tissue, cribriform fascia.

Cribriform fascia: A sieve-like fascia which is a localized membranous layer of subcutaneous tissue. It spreads over e saphenous opening & closes it. It is pierced by numerous opening for e passage of lymphatic vessels & great saphenous

veins.

FEMORAL TRIANGLE

A subfascial space of a triangular depression inferior to e inguinal ligament when e thigh is flexed, abducted, & laterally rotated.

Boundaries of e femoral triangle:1. Superior border: inguinal ligament.2. Medial border: aduuctor longus.3. Lateral border: Sartorius.4. Muscular floor: iliopsaoas laterally & pectineus medially.5. Roof: fascia lata, cribriform fascia, subcutaneous tissue, & skin.

Contents of e femoral triangle from lateral to medial:1. Femoral nerve.2. Femoral artery & its branches.3. Femoral veins & its proximal tributaries.4. Deep inguinal lymph nodes & associated lymph vessels.

Femoral sheath: Downward protrusion of fascial envelop (anterior: Fascia transversalis & posterior: Fascia

iliaca) lining e abdominal wall into e thigh. Surrounds femoral vessels & lymphatics. 3 compartments from lateral to medial:

1. Femoral artery.2. Femoral vein.3. Femoral canal.

Femoral canal: A short fascial tube which diminishes in width from above to downwards. Closed inferiorly by fusion of its walls with e tunica adventitia of e femoral artery. Upper end is bounded by femoral ring which faces into e abdomen & is separated from e

abdominal cavity only by e peritoneum. Function: allows e expansion of femoral vein within e sheath during massive venous return

from e distal part of e lower limb. Contents: fat, lymph nodes, & lymph vessels. Boundaries of e femoral ring:

1. Anterior: inguinal ligament.2. Posterior: pectin of e pubic bone.3. Medial: sharp edge of e lacunar ligament.4. Lateral: femoral vein.

ADDUCTOR CANAL

Also known as hunter canal or subsartorial canal. A long (~ 15 cm) & narrow passageway in e middle third of e thigh. It extends from e apex of e femoral triangle (where Sartorius crosses over adductor longus) to

Semitendinosus

Gluteus Maximus

Sartorius

Vastus Medialis

Bicep Femoris

Vastus Lateralis

e adductor hiatus in e tendon of adductor magnus. It provides an intermuscular passage for: Boundaries of femoral canal:

1. Antero-lateral border: vastus medialis.2. Antero-medial: Sartorius.3. Posterior: adductor longus & adductor magnus.

In e inferior 3rd to half of e canal, a tough subsartorial or vastoadductor fascia spans b/w adductor longus & vastus medialis, forming e anterior wall of e canal deep to Sartorius.

Surgical importance: exposure & ligation of femoral artery in this canal by John Hunter for e aneurysm of popliteal artery.

ADDUCTOR HIATUS

An opening or gap b/w:1. E aponeurotic distal attachment of e adductor part of adductor magnus.2. E tendinous attachment of e hamstring part.

It transmits e femoral vessels from e adductor canal in e thigh to e popliteal fossa posterior to e knee.

It is located just lateral & superior to e adductor tubercle of e femur.

APPLIED ANATOMY

1. Anterior thigh:a. Femoral hernia: a protrusion of peritoneum or abdominal contents through e femoral ring

into e thigh which causes swelling inferior & lateral to e pubic tubercle.b. Tredelenburg test for varicose vein: lack of competence of valves of superficial venous

system at sapheno-femoral junction leads to severe varicosities t/out e great saphenous system.

2. Middle thigh - obturator nerve paralysis: A rare condition causing pain down w medial side of e upper thigh & weakness of adductor

group of muscles. Seen in lateral pelvic wall pathology, often related to malignancy. E testing of obturator nerve is at e skin over e medial thigh during hip adduction.

Anterior

Posterior

Lateral Thigh

Psoas

Inguinal Ligament

Pectineus

Adductor Longus

Gracilis

Iliacus

Iliopsoas

Femoral VAN

Rectus Femoris

Sartorius

Medial Thigh

Gracilis

Tensor Fascia Lata

Iliotibial Tract

Pes Anserinus

MUSCLES OF THE LEG

MUSCLES ORIGIN INSERTION NERVE SUPPLY

NERVE ROOT

ACTIONS

ANTERIOR COMPARTMENT

TIBIALIS ANTERIOR

Lateral surface of shaft of tibia & interosseous membrane

Medial cuneiform & base of 1st

metatarsal bone.

Deep peroneal

nerve

L4 & L5

1. Extends foot at ankle joint.

2. Inverts foot at subtalar & transverse tarsal joint.

3. Holds up medial longitudinal arch.

PERONEUS TERTIUS

Interior 3rd of anterior surface of

fibula & interosseous membrane

Base of 5th

metatarsal bone

L5 & S1

1. Extends foot at ankle joint.

2. Inverts foot at subtalar & transverse tarsal joint.

EXTENSOR DIGITORUM

LONGUS

Lateral condyle of tibia & superior ¾ of anterior surface of

interosseous membrane

Middle & distal phalanges of lateral 4 toes

Extends lateral 4 digits & dorsiflex ankle joint.

EXTENSOR HALLUSIS LONGUS

Middle part of anterior surface of

fibula & interosseous membrane

Dorsal aspect of base of distal

phalanx of great toe

Extends big toe & dorsiflex ankle joint.

EXTENSOR DIGITORUM

BREVISCalcaneum

By 4 tendons into e proximal phlanx of big

toe & long extensor

tendons to 2nd – 4th toes

S1 & S2 Extends toes.

LATERAL COMPARTMENT

PERONEUS LONGUS

Head & superior 2/3 of lateral surface of

fibula

Base of 1st

metatarsal & medial

cuneiform Superficial peroneal

nerve

L5, S1, & S2

Evert foot & weakly plantarflex ankle.

PERONEUS BREVIS

Inferior 2/3 of lateral surface of fibula

Dorsal surface of tuberosity on lateral side of

base of 5th

metatarsal

POSTERIOR COMPARTMENTSUPERFICIAL LAYER

GASTROC-NIMEUS

1. Lateral head: lateral

aspect of lateral condyle of femur2. Medial

head: popliteal surface of femur Posterior

surface of calcaneus with Achilles tendon

Tibial nerve S1 & S2

Plantarflexes ankle, raises heel during walking, & flexes leg at

knee joint.

PLANTARIS

Inferior end of lateral supracondylar line of

femur & oblique popliteal ligament

Weakly assists gastrocnemius in plantarflexing ankle & flexing

knee.

SOLEUS

Posterior aspect of head of fibula, superior 4th of

posterior surface of fibula & soleal line

Plantarflexes ankle & steadies leg on foot.

DEEP LAYER

POPLITEUS

Lateral surface of lateral condyle of femur & lateral

meniscus

Posterior surface of tibia

superior to soleal line

Tibial nerve L4, L5, &

S1Weakly flexes knee & unlocks

it.

FLEXOR DIGITORUM

LONGUS

Medial part of posterior surface of tibia & inferior part

of interosseous membrane

Bases of distal phalanges of

lateral 4 digits

S2 & S3Flexes lateral 4 digits &

plantarflexes ankle, supports longitudinal arches of foot.

FLEXOR Inferior 2/3 of posterior surface of

Base of distal phalanx of great

Flexes great toe & plantarflexes ankle, supports medial

HALLUCIS LONGUS

fibula & inferior part of interosseous

membranetoe longitudinal arches of foot.

TIBIALIS POSTERIOR

Interosseous membrane, posterior

surface of tibia inferior to soleal line, & posterior surface

of fibula

Tuberosity of navicular,

cuneiform, & cuboid, & bases

of 2nd – 4th

metatarsals

L4 & L5 Plantarflexes ankle & inverts foot.

THE LEG

PORTION DETAILS

FASCIA CRURI

E deep fascia of e leg which attaches to e anterior & medial borders of e tibia where it is continuous with its periosteum.

Thick in e proximal part of e anterior aspect of e leg where it forms e proximal attachment of underlying muscles.

Thinner distally & forms thickened bands both superior & anterior to e ankle joint as e extensor retinacula.

Anterior & posterior intermuscular septa pass from deep surface of e lateral fascia & attach to e corresponding margins of e fibula.

ANTERIOR COMPARTMENT

RETINACULUM

A band-like thickening of fascia that binds e tendons of e anterior compartment muscles before & after they cross e ankle joint.

Prevents e muscle from bowstringing anteriorly during dorsiflexion of e joint. 2 retinacula in e anterior compartment:

1. E superior extensor retinaculum: Strong, broad band of deep fascia, passing from e fibula to tibia, proximal to e malleoli.

2. E inferior extensor retinaculum: Y-shaped of deep fascia which attaches laterally to e anterosuperior surface of e

calcaneus. Forms a strong loop around e tendons of e fibularis tertius & e EDL.

TIBIALIS ANTERIOR

E most medial & superficial dorsiflexor. A slender muscle that lies against e lateral surface of tibia. Its tendon:

Begins halfway down e leg & descends along e anterior surface of e leg. Passes within its own synovial sheath deep to 3 sup. & inf. extensor retinacula to its

attachment at e medial side of e foot. Is located e farthest from e axis of e ankle joint to become e strongest dorsiflexor.

Acts synergistically with TP to invert e foot because both cross e subtalar & transverse tarsal joint to attach to e medial border of e foot.

EXTENSOR DIGITORUM

LONGUS

E most lateral of e anterior leg muscles. Its proximal attachment: Becomes tendinous superior to e ankle to form 4 tendons that attach to e phalanges of e

digits. Each of its tendons:

Surrounded by a common synovial sheath as they diverge on e dorsum of e foot. Forms a membranous extensor expansion over e dorsum of e proximal phalanx of e toe

which divides into 2 lateral bands (distal phalanx) & 1 central band (middle phalanx).

EXTENSOR HALLUCIS LONGUS

A thin muscle that lies deeply b/w TA & EDL at its superior attachment to e middle half of e fibula & interosseus membrane.

Rises to e surface in e distal 3rd of e leg, passing deep to e extensor retinacula. Courses distally along e crest of e dorsum of e foot to e great toe.

PERONEOUS TERTIUS

A separated part of e EDL which shares its synovial sheath. Proximally, e attachments & fleshy part of e EDL & FT r continuous but tendon is separate

distally & attaches to e base of e 5th metatarsal. Acts as weak dorsiflexor & acts at e subtalar & transverse tarsal joints for eversion. Can sense sudden inversion to contract reflexively to protect e anterior tibiofibular

ligament.

DORSIFLEXION

A weak & short movement: ¼ of e strength of e plantarflexion. Used in:

1. Swing phase of walking:a. Concentric contraction: keeps e forefoot elevated.b. Eccentric concentration: controls e lowering of e forefoot to e floor following heel

strike.2. Standing phase: reflectively pulls e leg anteriorly on e fixed foot when e body starts to

lean posteriorly.3. Descending a slope: used to dig in one’s heel.

LATERAL COMPARTMENT

PERONEOUS BREVIS

A fusiform & shorter muscle that lies deep to e PL. Its broad tendon:

Grooves e posterior aspect of e lateral malleolus & can be palpated inferior to it. Traverses e superior compartment of e inferior fibular retinaculum & passes superior to

e fibular trochlea of e calcaneus. Merges with e tendon of PT which attaches directly to e proximal phalanx of 5th digit.

PERONEOUS LONGUS

E longer & most superficial of e lateral leg muscles arising much > superiorly on e shaft of e fibula.

It extends from e head of fibula to e sole of e foot. It enters a groove on e anterior aspect of e cuboid bone, then crosses e sole of e foot &

running obliquely & distally to reach its attachment to e 1st metatarsal & medial cuneiform bone.

It helps steady e leg on e foot during standing with only one foot.

RETINACULUM Only 2 retinacula in e lateral compartment: superior & inferior fibular retinacula.

Spans b/w e distal tip of e fibula & e calcaneus.

POSTERIOR COMPARTMENT

SUPERFICIAL LAYER

GASTROCNEMIUS

E most superficial muscle in e posterior compartment & most prominent part of caft. It is a fusiform, 2-headed, 2 joint muscle with e medial head slightly larger & extending >

distally than its lateral partner. E heads come together at popliteal fossa where they form its upper boundaries. It contraction produces rapid movement during running & jumping d/t its fibers which r

mainly vertical & largely of e white, fast-twitch variety. It is capable is capable of acting on both knee & ankle joints, but it is most effectively when

e knee is extended.

SOLEUS

It is located deep to gastrocnemius & is known as workhorse of plantarflexion. It is a large, flatter muscle which has a continuous proximal attachment in e shape of an

inverted U to e posterior aspect of fibula & tibia. It has an arch known as tendinous arch of soleus where popliteal artery & tibial nerve exit

from popliteal fossa. Its actions:

1. May act with gastrocnemius in plantarflexion of ankle joint: A strong but relatively slow plantarflexor of e ankle joint because it is composed of

largely red, fatigue-resistant, slow-twitch muscle fibers.2. An antigravity muscle which contracts antagonistically but cooperatively with e

dorsiflexor muscles of e leg to maintain balance.3. Continuously active during standing.

PLANTARIS

A small muscle with a short belly but a long tendon. It is a vestigial muscle which is absent from 5 – 10% of people. It acts with gastrocnemius but is insignificant as either e flexor of e knee or plantarflexor of

knee joint. Its long, slender tendon is easily mistaken for a nerve & runs distally b/w e other 2

muscles. It can be removed for grafting during constructive surgery w/o causing disability.

TRICEPS SURAE & ACHILLES TENDON

1. Triceps surae: Composed of soleus & gastrocnemius which share a common tendon called Achilles

tendon inserted into e calcaneal tuberosity. They r very strong & heavy because they lift. Propel, & accelerate e weight of e body

when walking & etc.2. Calcaneal tendon:

E most powerful & thickened tendon in e body. It is ~ 15 cm in length d/t e continuation of e flat aponeurosis formed halfway where e

belies of gastrocnemius terminates. Has an elastic ability to absorb energy, shock, recoil, & releasing energy.

DEEP LAYER

TIBIALIS POSTERIOR

E deepest muscle which lies b/w FDL & FHL. Distally, it attaches primarily to navicular bone, but has also other attachments to other tarsal

& metatarsal bones. Its actions:

1. Acts synergistically with e TA to invert e foot.2. 1o role: to support or maintain e medila longitudinal arch during weight bearing.3. Stance phase: e muscle is relaxed.4. Standing phase: acts synergistically with TA to depress e lateral side of e foot & pull

medially on e leg as needed to counteract lateral leaning for balance.

FLEXOR DIGITORUM

LONGUS

Smaller than FHL even it moves e 4 digits. It passes diagonally into e sole of e foot which is superficial to e tendon of FHL. Its direction is realigned by e quadrates planate muscle which attaches to e posterolateral

aspect of FDL tendons as it divides into 4 tendons (1 for each digits).

FLEXOR HALLUCIS LONGUS

A powerful flexor of all joints of e great toe. E FHL delivers a final thrust via flexion of e great toe for e preswing phase of e gait cycle. Its tendon passes posterior to e distal end of e tibia & occupies a shallow groove on e posterior

surface of e talus which is continuous with e groove on e plantar surface of e talar shelf. Its tendon also runs b/w 2 sesamoid bones in order to protect it from 3 pressure of e head of e

1st metatarsal bone.

POPLITEUS

A thin, triangular muscle that forms e inferior part of e floor of e popliteal fossa. E apex of its fresh belly emerges from e joint capsules of e knee joint.its fleshy distal

attachment is covered by popliteal fossa reinforced by a fibrous expansion from e semimembranosus muscle.

Its actions:1. During flexion, it assists in pulling e lateral meniscus posteriorly.2. In e knee partially flexed, it contracts to assist posterior cruciate ligament in preventing

anterior displacement of e femur on e inclined tibial plateau.3. In e knee fully extended position, e popliteus acts to rotate e femur laterally 5o on e tibial

plateau.4. It aids e medial hamstring in rotating e tibia medially beneath e femoral condyle.

APPLIED 1. Anterior compartment syndrome: pain, decreased dorsiflexion, extension of toes, & sensation in 1st skin cleft.

Tibialis Posterior

Flexor Digitorum Longus

Ligamentum Patelli

ANATOMY

2. Lateral compartment syndrome: pain, decreased plantarflexion & eversion, & sensation of dorsal foot & toes.

3. Posterior compartment syndrome: Divided by deep transverse intermuscular septum into superficial & deep syndromes. Superficial syndrome gives decreased plantarflexion & sural nerve sensation. Deep syndrome gives decreased plantar & toe flexion & tibial nerve sensation.

4. Nerve injuries:a. Common peroneal nerve injury:

Motor dysfunction in e anterior & lateral compartments of e leg. Test is by asking e patient to walk on their heels: foot drop.

Sensory deficit: lateral cutaneous nerve of calf & e cutaneous branch to dorsum of e foot. Results in decreased proprioception knee, ankle, & toe joints.

b. Deep peroneal nerve injury: area of sensory changes in 1st skin cleft found in lesion of deep peroneal nerve.

c. Superficial nerve injury: area of sensory changes on e dorsum of foot except 1st skin cleft.

Lateral Leg

Anterior Leg

Superficial Peroneal N Extensor Digitorum Longus

er

Extensor Digitorum Longus

Soleus

Achilles Tendon

Peroneus Longus

Gastrocnemius

Peroneus Brevis

Peroneus Longus

Tibialis Anterior

Popliteus

Tibial Nerve & Posterior Tibial Artery

MUSCLES OF GLUTEAL REGION

MUSCLES ORIGIN INSERTION NERVE SUPPLY

NERVE ROOT

ACTIONS

GLUTEUS MAXIMUS

1. Ilium posterior to posterior gluteal line

2. Dorsal surface of sacrum &

coccyx3. Sacrotuberous

ligament

1. Most end in iliotibial

tract that inserts into

lateral condyle of tibia

2. Gluteal tuberosity of

femur

Inferior gluteal nerve

L5, S1, & S2

1.Extends thighs & assists in its lateral rotation.

2.Steadies thigh & assists in raising trunk from flexed

position.

GLUTEUS MEDIUS

External surface of ilium b/w anterior &

posterior gluteal line

Lateral surface of greater

trochanter of femur Superior

gluteal nerve

L5 & S1 1.Abduct & medialy rotate thigh.

2.Steady pelvis on leg when opposite leg is raised.

GLUTEUS MINIMUS

External surface of ilium b/w anterior &

inferior gluteal line

Anterior surface of greater

trochanter of femur

PIRIFORMIS

Anterior surface of sacrum &

sacrotuberous ligament

Superior border of greater

trochanter of femur

Branches of ventral rami S1 & S2

OBTURATOR INTERNUS

Pelvic surface of obturator

membrane & bones

Medial surface of greater

trochanter of femur

Nerve to obturator internus

L5 & S1

1. Laterally rotate extended thigh & abduct

flexed thigh.2. Steady femoral

head in acetabulum.

SUPERIOR & INFERIOR GEMELLI

1. Superior: ischial spine

2. Inferior: ischial tuberosity Nerve to

quadratus femorisQUADRATUS

FEMORISLateral border of ischial tuberosity

Quadrate tubercle

Obturator internus

Gluteal Region

Gluteus medius

Piriformis

Sciatic nerve

Quadratus femoris

Sacrotuberous ligament

Superior gemellus

Obturator internus

Inferior gemellus

Gluteus minimus

Superior gluteal artery

THE GLUTEAL REGION

PORTION DETAILS

OVERVIEW

A large transitional zone b/w trunk & limb. It is posterior to e pelvis, inferior to e level of e iliac crests & extending laterally & anteriorly to e

greater trochanter. E intergluteal cleft separates e buttock from each other. E gluteal fold demarcates e inferior boundary of e buttock & e superior boundary of e thigh. It is composed of gluteal muscles, gluteal ligaments, & thick subcutaneous fat.

GLUTEAL MUSCLES1. Superficial layer:

Consists of 3 large glutei & e tensor fascia lata which have proximal attachment to e posterolateral surface & margins of ala of ilium.

R mainly extensors, abductors, & medial rotators of e thigh.2. Deep layer:

Consists of smaller muscles such as piriformis, obturator internus, externus gemelli, & quadrates femoris covered by e gluteus maximus.

Have distal attachment on or adjacent to e intertrochanteric crest of e femur. R mainly lateral rotators of e thigh & stabilizer of e hip joint.

GLUTEAL LIGAMENT E parts of e bony pelvis, e hip bones, sacrum, & coccyx r bound together by dense ligaments:

1. Sacrotuberous ligament: b/w sacrum & ischial tuberosity. 2. Sacrospinous ligaments: b/w sacrum & ischial spine.

These ligaments convert e sciatic notches into greater & lesser sciatic foramina:1. Greater sciatic foramen: e passageway for structures entering or leaving e pelvis.2. Lesser sciatic foramen: e passageway for structures entering or leaving e perineum.

STRUCTURES DEEP TO GLUTEUS MAXIMUS1. Superficial muscles:

a. Gluteus medius.b. Gluteus minimus.

2. Other structures:a. Nerves.b. Vessels.

3. Deep or short muscles:a. Piriformis.b. Superior gemellus.c. Obturator internus.d. Inferior gemellus.e. Quadrates femoris.

STRUCTUES PASSING THROUGH GREATER SCIATIC FORAMEN1. Structures entering above piriformis: Superior gluteal nerve & vessels.

2. Structures entering below piriformis:a. Laterally:

i. Sciatic nerve.ii. Nerve to quadratus femoris.

iii. Posterior cutaneous nerve of e thigh.b. Intermediate: inferior gluteal nerve & vessels.

c. Medially:i. Internal pudendal artery.

ii. Pudendal nerve.iii. Nerve to obturator internus.

STRUCTUES PASSING THROUGH LESSER SCIATIC FORAMEN1. Tendon of Obturator internus.2. Nerve to Obturator internus.

3. Pudendal nerve.4. Internal pudendal vessels.

APPLIED ANATOMY1. Transverse perineal block:

Internal pudendal vessels exit e greater sciatic foramen by crossing e ischial spine, but e accompanying pudendal nerve lies medial to them on e sacrospinous ligament.

Ischial spine palpated through e vagina wall. A hypodemic needle is passed through e vagina medial to e ischial spine & through e sacrospinous ligament. E sensory nerve impulses from e perineum r blocked by injecting an anesthetic agent in e vicinity of e pudendal

nerve, as it crosses e sacrospinous ligament. 2. Surface anatomy of sciatic nerve:

Midway b/w PSIS & ischial tuberosity. From e lower border of e piriformis, curves inferiorly midway b/w e ischial tuberosity & e greater trochanter,

covered by e gluteus maximus.3. Sciatica:

Pain along e sensory distribution of e sciatic nerve. Prolapsed intervertebral disc, intrapelvic tumors, or inflammation of e sciatic nerve or its terminal branches can

cause sciatica.4. Gluteus maximus:

E upper lateral quadrant of e gluteal region is chosen for giving intramuscular injection because of large muscle mass & relatively few neurovascular branches r subjected to e ensuing injection.

5. Testing spinal segment: S3 & S4 for e skin over medial gluteal region.

ARTERIES OF THE LOWER LIMB

ARTERIES DETAILS

COMMON ILIAC

ARTERIES

E terminal branches of abdominal aorta which begin at about e level of L4. Each (Lt. & Rt. CIA) passes inferiorly about 5 cm & gives rise to 2 branches:

1. E internal iliac artery. 2. E external iliac artery. E general distribution: pelvis, external genitalia, & lower limbs.

ARTERIES OF THE PELVIC REGION

Internal Iliac

Artery

Also known as hypogastric artery that is e primary artery of e pelvis. Begins at e bifurcation of common iliac arteries anterior to e sacroiliac joint at e level of lumbosacral IV

disk. Passes posteromedially as descend in e pelvis & divides into anterior & posterior divisions. Main distribution: pelvis, buttock, external genitals, & thigh.

External Iliac

Artery

Larger than IIA, but still begins at e same position. Pathway: Descends along e medial border of e psoas major muscle → passes e pelvic brim posterior to

inguinal ligaments → becomes femoral artery. Distribution:

1. E lower limb. 3. E cremasteric muscle in males.2. Muscles of e anterior abdominal wall. 4. E round ligament of uterus in females & lower

limbs.

ARTERIES OF THE GLUTEAL REGION

Superior Gluteal Artery

E largets branch of internal iliac artery which passes posteriorly b/w e lumbosacral trunk & S1 nerve. Enters e gluteal region through e upper part of e greater sciatic foramen above e piriformis. Divides into:

1. Superficial branch: gluteus maximus & skin over e proximal attachment of e muscle.2. Deep branch: gluteus medius & minimus as well as tensor of fascia lata.

Anastomoses with e inferior gluteal & medial circumflex femoral arteries.

Inferior Gluteal Artery

Arises from e internal iliac artery & passes posteriorly through e parietal pelvic fascia b/w S1 & S2 nerves.

Enters gluteal region via greater sciatic foramen below piriformis, deep to gluteus maximus, & medial to sciatic nerve.

Distribution: gluteus maximus, obturator internus, quadratus femoris, & superior part of hamstring. Anastomoses with superior gluteal artery & participates in cruciate anastomosis of e thigh.

Internal Pudend

al Artery

Arises from internal iliac artery & lies anterior to e inferior gluteal artery. Parallel to pudendal nerve, it enters gluteal region via greater sciatic foramen inferior to piriformis. Leaves e gluteal region by crossing e ischial spine & enters e perineum through lesser sciatic foramen. Distribution: skin, external genitalia, & muscle of e perineal region.

ARTERIES OF THE THIGH

Femoral Artery

E continuation of e external iliac artery distal to inguinal ligament. Enters e femoral triangle deep to e midpoint of e inguinal ligament & lateral to femoral vein. Its pulsation r palpable because of its superficial position deep to fascia lata where it lies &

descends down e adductor canal (b/w vastus medialis & adductor longus & magnus). Branches of femoral artery:

1. Proximal part:a. Superficial circumflex iliac artery: passes via saphenous opening & runs to e area around

ASIS.b. Superficial epigastric artery: passes via saphenous opening to lumbar region & supplies e

skin of abdominal wall.c. Superficial external pudendal: passes via e saphenous opening to pubic tubercle & supplies

e skin of scrotum & labia majora.d. Deep external pudendal: passes medially to supply e skin of scrotum & labia majora.

2. Lateral of posterior part - profunda femoris artery: Arises from lateral side at about 4 cm below inguinal ligament. Enters medial compartment of thigh behind e adductor longus. Gives of 3 perforating arteries & ends as 4th perforating artery. E branches:

a. Just below e origin: medial (head & neck blood supply) & lateral (muscle of e lateral side of e thigh) circumflex femoral arteries.

b. Perforating branches in medial compartment.c. Descending genicular at near its terminal.

Perforating Arteries

Consists of 4 perforating arteries of e deep artery of e thigh, 3 in e anterior compartment, & 1 is e terminal branch.

They r large vessels, unusual in e limbs for their transverse, intercompartmental course. They perforate e aponeuratic portion of e distal attachment of e adductor magnus to enter e

posterior compartment. Distribution: hamstring muscles in posterior compartment, vastus lateralis muscle in anterior

compartment (by piercing lateral intermuscular setum), & sciatic nerve.

Obturator Artery

Arises from internal iliac artery which passes via obturator foramen into medial compartment of e thigh.

Distribution:1. E posterior branch: muscles attached to ischial tuberosity.2. E anterior branch: obturator externus, pectineus, adductors of thigh, & gracillis.

Anastomosis of the

Thigh

1. E Trochanteric Anastomosis: Provides e main blood supply to e head of e femur. E nutrient arteries pass along e femoral neck beneath e capsule. E following arteries take part in e anastomosis: superior & inferior gluteal artery (descending

branches) as well as medial & lateral femoral circumflex artery (ascending branches).2. E Cruciate Anastomosis:

Situated at e level of e lesser trochanter of e femur. Together with trochanteric anastomosis, it provides a connection b/w internal iliac & femoral

artery. E following arteries take part in e anstomosis: inferior gluteal artery (descending branch),

medial & lateral femoral circumflex artery (transverse branches), & ascending branch of 1st perforating artery.

ARTERIES OF THE KNEE JOINT

Popliteal Artery

E continuation of e femoral artery which begins when it passes through e adductor hiatus. It passes inferolaterally through popliteal fossa & ends at e inferior border of e popliteus. In e fossa, e artery gives off 5 genicular branches: 2 superior, 2 inferior, & I middle genicular

arteries. Immediately after soleus arch, it divides into anterior & posterior tibial arteries. E muscular branches of popliteal artery supply e hamstring, gastrocnemius, soleus, & plantaris

muscles.

Genicular Anastomos

is

Formed by 10 vessels at e knee joint:1. E genicular branches of femoral & popliteal arteries:

2 from above: e descending branch of e lateral circumflex femoral artery & e descending genicular branch of e femoral artery.

5 from popliteal artery: 2 superior, 2 inferior, & I middle genicular arteries.2. Anterior & posterior recurrent branches of anterior tibial recurrent & circumflex fibular artery (3

from below).

ARTERIES OF THE LEG

Anterior Tibial Artery

E smaller terminal branch of popliteal artery which supplies structures in e anterior compartment of e leg.

It begins at e inferior border of e popliteus muscle & immediately passes anteriorly through a gap in e superior part of e interosseous membrane to descend on its anterior surface b/w TA & EDL.

At ankle joint b/w e 2 malleli, it becomes dorsalis pedis artery of e foot.

Posterior Tibial Artery

E largest & > direct terminal branch of e popliteal artery which provides e blood supply to e posterior compartment of e leg & to e foot.

It begins after e popliteal artery passes through e soleus arch. Close to its origin, it gives branch to peroneal artery which runs lateral & parallel to it within e deep

subcompartment. During its descent, it is accompanied by tibial nerve & vein & runs posterior to e medial malleolus from

which it is separated by e tendons of TB & FDL. Inferior to medial malleolus, it runs b/w e tendon of FHL & FDL. Deep to flexor retinaculum & e origin of abductor hallucis, it divides into medial & lateral plantar

arteries.

Peroneal Artery

Branch of posterior tibial artery which srises inferior to e distal border of e popliteus & soleus arch. It descends obliquely toward e fibula & passes along its medial side usually within FHL. It gives muscular branches to e popliteus & other muscles in lateral & posterior compartments of leg. It also gives rise to e nutrient artery of e fibula & ditally to e perforating branch, terminal lateral

malleolar & calcaneal branch. At e dorsum of foot, it anastomoses with arcuate artery. E lateral calcaneal branches supply e heel & e lateral malleolar branch joins other maleolar branches

to form a periarticular arterial anastomoses of e ankle.

ARTERIES OF THE FOOT1. Arteries of e dorsal of foot:

a. E Dorsalis Pedis Artery: Major blood supply of e forefoot which is e direct continuation of e anterior tibial artery. Begins midway b/w e malleoli & runs anteromedially deep to e inferior extensor retinaculum b/w EHL & EDL

tendons on e dorsum of e foot. It passes to e 1st interosseous space where it divides into 1st dorsal metatarsal artery & a deep plantar artery

(forms deep plantar arch with lateral plantar artery).b. E Lateral Tarsal Artery:

A branch of e dorsal artery of e foot which runs laterally in an arched course beneath EDB. It supplies e underlying tarsals & joints. It anastomoses with other branches such as arcuate artery.

c. E 1st Dorsal Metatarsal Artery: supplies both sides of e great toe & e medial side of 2nd toe.d. E Arcuate Artery:

Runs laterally across e bases of e lateral 4 metatarsals, deep to e extensor tendons. It anastomoses with e lateral tarsal artery at e lateral aspect of e forefoot to form an arterial loop. It gives rise to 2nd, 3rd, & 4th dorsal metatarsal arteries which r connected to e plantar arch & plantar

metatarsal arteries via perforating branches. Distally, each dorsal metatarsal artery divides into 2 dorsal digital arteries for e dorsal of e foot.

2. Arteries of e sole of e foot:derived from e posterior tibial artery.

a. Medial Plantar Artery: E smaller terminal branch of e posterior tibial artery. It gives rise to a deep branch that supplies mainly muscle of e great toe. Its larger superficial branch supplies e skin on e medial side of e sole. Its digital branches anastomose with medial plantar artery. A superficial plantar arch is formed when e superficial branch anastomoses with e lateral plantar artery or e

deep plantar arch.b. Lateral Plantar Artery:

Much larger than e medial plantar artery, arises with & accompanies e lateral plantar nerve. It runs laterally & anteriorly deep to adductor hallucis & then b/w e FDB & quadrates plantae. It arches medially across e foot to form e plantar arch with deep plantar artery. E deep plantar arch gives rise to 4 plantar metatarsal arteries, perforating branches, & others which supply e

skin, fascia, & muscle of e sole. Plantar metatarsal arteries divide & form plantar digital arteries which supply e adjacent digits.

CLINICAL NOTES

1.Femoral artery:a. Femoral artery pulsation: mid inguinal point – palpate midway b/w e symphysis pubis & ASIS.b. Femoral artery cannulation: few cms below inguinal ligament – insert needle directly below

femoral pulse.2.Popliteal artery: recording of blood pressures of lower lim by catherization, aneurysm, &

artherosclerosis.3.Femoral vein catheterization: pass dye into blood so as to take X-rays or angiograms.

PERONEAL ARTERY

ARTERIES OF THE LOWER LIMB

ABDOMINAL AORTA

COMMON ILIAC ARTERY

EXTERNAL ILIAC ARTERYINTERNAL ILIAC ARTERY

FEMORAL ARTERY SUPERIOR GLUTEAL ARTERY

INFERIOR GLUTEAL ARTERY

INTERNAL PUDENDAL ARTERY

OBTURATOR ARTERY

1. Superficial circumflex iliac

artery2. Superficial epigastric artery

3. Superficial external pudendal

4. Deep external pudendal

PERFORATING ARTERIES: 1st, 2nd,3rd, & 4th.

MEDIAL PLANTAR

POSTERIOR TIBIAL

PLANTAR ARCH

ANTERIOR TIBIAL

POPLITEAL ARTERY

ARCUATE ARTERY

DORSALIS PEDIS LATERAL PLANTAR

2 SUPERIOR, 2 INFERIOR, & 1 MIDDLE GENICULAR

ARTERIES

PROFUNDA FEMORIS

VENOUS DRAINAGE OF THE LOWER LIMB

VEINS DETAILS

SUPERFICIAL VEINS (SUBCUTANEOUS TISSUE)

GREAT SAPHENOUS

VEIN

Formed by e union of e dorsal vein of e great toe & e dorsal venous arch of e foot. It has 10 – 12 valves which r > numerous in leg than thigh & located just inferior to e perforating

veins. Venous valves r cusps of endothelium with cup-like valvular sinuses that fill from above. E valvular mechanism:

Occludes e lumen when full, thus preventing reflux of blood distally & making e flow unidirectional.

Breaks e column of blood in e saphenous vein into shorter segments, thus reducing back pressure.

Make it easier for e musculovenous pump to overcome e force of gravity to return e blood to e heart.

Courses:1. Ascends anterior to e medial malleolus.2. Passes posterior to e medial condyle of femur (about 1 palm width posterior from patella).3. Anastomoses freely with small saphenous vein.4. Transverse e saphenous opening in e fascia lata.5. Empties into femoral vein.

E tributaries:1. Accessory saphenous vein: tributaries from medial & posterior aspects of e thigh (main

connection b/w great & small saphenous veins).2. Lateral & anterior cutaneous veins: networks of veins in e inferior part of e thigh.3. Superficial circumflex, superficial epigastric, & external pudendal veins.

SMALL SAPHENOUS

VEIN

Arises on e lateral side of e foot from e union of e dorsal vein of e little toe with e dorsal venous arch.

Its diameter remains uniform as it ascends e limb because e blood it receives is continuously shunted from it to e deep veins through perforating veins.

Courses:1. Ascends posterior to e lateral malleolus as a continuation of e lateral marginal vein.2. Passes along e lateral border of e calcaneal tendon.3. Inclines to e midline of e fibula & penetrates e deep fascia.4. Ascends b/w e heads of e gastrocnemius muscle.5. Empties into e popliteal vein in e popliteal fossa.

DEEP VEINS (BENEATH THE DEEP FASCIA)

FEMORAL VEIN

This vein is e continuation of e popliteal vein proximal to e adductor hiatus. As it ascends through e adductor canal, e femoral vein lies posterolateral & then posterior to e

femoral artery. E femoral vein enters e femoral sheath lateral to e femoral canal & ends posterior to e inguinal

ligament where it becomes external iliac vein. In e inferior part of e femoral triangle, e femoral vein receives e deep vein of e thigh, e great

saphenous vein, & other tributaries. E deep vein of e thigh formed by e union by e union of 3 or 4 perforating veins, enters e femoral

vein ~ 8 cm inferior to inguinal ligament & ~ 5 cm inferior to e termination of e great saphenous vein.

E tributaries:1. Profunda femoris vein. 3. Medial & lateral circumflex femoral veins.2. Great saphenous vein. 4. Muscular veins.

POPLITEAL VEIN

Begins at e distal border of e popliteus as a continuation of e posterior tibial vein. It also has several valves. Courses:

E vein lies close to e popliteal artery, lying superficial to it, & in e same fibrous sheath. Initially posteromedial to e artery & lateral to e tibial nerve. Superiorly, it lies posterior to e artery, b/w this vessel & e overlying tibial nerve. Superiorly, it becomes e femoral vein as it traverses e adductor hiatus.

It also receives blood drainage from small saphenous vein.

ANTERIOR TIBIAL VEIN

E paired anterior tibial veins arise in e dorsal venous arch & accompany e anterior tibial artery. It ascends in e interosseous membrane b/w e tibia & fibula & unites with e posterior tibial veins to

form e popliteal vein. E anterior tibial veins drain e ankle joint, knee joint, tiiofibular joint, & anterior portion of e leg.

POSTERIOR E paired posterior tibial veins, which sometimes unite to form a single vessel, r formed by e

PLANTAR METATARSAL

PLANTAR DIGITAL

DORSAL METATARSAL

DORSAL DIGITAL ------- ANASTOMOSIS

VENOUS DRAINAGE OF THE LOWER LIMB

INFERIOR VENA CAVA

EXTERNAL ILIAC VEIN INTERNAL ILIAC VEIN

COMMON ILIAC VEIN

FEMORAL VEIN

POSTERIOR TIBIAL VEIN

POPLITEAL VEIN

DEEP FEMORAL VEIN

DEEP PLANTAR VENOUS ARCH

MEDIAL & LATERAL PLANATAR VEIN

DORSAL VENOUS ARCH

ANTERIOR TIBIAL VEIN

PERONEAL VEIN

DORSAL METATARSAL

DORSAL VENOUS ARCH

SMALL SAPHENOUS VEIN

GREAT SAPHENOUS VEIN

TIBIAL VEIN

medial & lateral plantar veins, posterior to e medial malleolus of e tibia. It also accompanies e posterior tibial artery through e leg. It ascends deep to e muscles in e posterior aspect of e leg & drain e foot & posterior compartment

muscles. ~ 2/3 of e way of e way up r leg, e posterior tibial veins drain blood from e peroneal veins, which

drain e lateral & posterior leg muscles. It unites with e anterior tibial veins just inferior to e popliteal fossa to form popliteal veins.

PERFORATING VEINS E perforating veins connect e superficial & deep veins. They have valves that direct e blood flow from superficial to deep as e result of limb motions & muscle contractions. E perforating veins penetrate e deep fascia close to their origin from e superficial veins at an oblique angle so that

when muscles contract & e pressure increases inside e deep fascia, e perforating veins r compressed. This compression also prevents blood from flowing from e deep to e superficial veins for proper venous return from

e lower limb to e heart against e gravity.

CLINICAL NOTES

1. Coronary bypass surgery: great saphenous vein is used to replace coronary artery.2. Varicose veins r common in long saphenous vein which is frequently tortuous & dilated when a

subject is in erect position.3. Deep vein thrombosis & pulmonary embolism.4. Superficial veins at e sides of e abdomen become noticeably enlarged in obstruction of e IVC.

Blood from e lower limbs by-passes e IVC & travels by way of e abdominal & thoracic walls to tributaries of e axillary veins & thence to e SVC.

THE SOLE OF THE FOOT

PORTION DETAILS

OVERVIEW

Foot: distal to leg.

Orientation of foot:1. Plantar:

sole.2. Dorsal

surface.

Functions:1. Support e body weight.2. Loose adapter or shock

absorber.3. Rigid lever.4. Locomotion.

Anatomical parts:1. E hindfoot: talus & calcaneus.2. E midfoot: nsvicular, cuboid,

& cuneiform.3. E forefoot: metatarsal &

phalanges.

LAYERS OF FOOT

SKIN Dorsal surface is thinner & less sensitive than plantar surface. Plantar skin is hairless, contains numerous sweat glands & entirely sensitive especially e

thinner-skinned area underlying e arch.

SUPERFICIAL FASCIA

E tissue is loose deep to e dorsal skin but is > fibrous in e sole. E fibrous septa (highly developed skin ligament, retinacula cutis):

1. Divides it into fat-filled areas making it a shock-absorbing pad especially over e heel.2. Anchors e skin to e underlying deep fascia to improve e grip of e sole.

E superficial fascia is also tough & thick.

DEEP FASCIA

Plantar Fascia: thickening of e deep fascia covering e sole of e foot. It has a thick central part & weaker medial & lateral part. Plantar aponeurosis:

Formed by e thick, central part of e plantar fascia. It is formed by longitudinally arranged bundles of dense fibrous connective tissue

investing e central plantar muscles. It arises posteriorly from e calcaneus & divides into 5 bands or processes, each of which

is continuous with e fibrous digital sheath & is anchored at a metatarsophalangeal joint. Inferior to e head of metatarsals, e aponeurosis is reinforced by transverse fibers forming

e superficial transverse metatarsal ligament. Functions:

1. Maintaining e longitudinal arches of e foot.2. Holds part of e foot together.3. Protects e underlying vessels, nerves, tendons, & their synovial sheath. 4. Forms e compartments of e sole.

COMPARTMENTS OF SOLE

MEDIAL COMPARTMENT

Covered superficially by thinner medial plantar fascia. It contains:

1. Medially: Abductor hallucis & flexor hallucis brevis. 2. Centrally beneath metatarsal: e tendon of flexor hallucis longus3. E medial plantar nerve & vessels.

CENTRAL COMPARTMENT

Covered superficially by e dense plantar aponeurosis. It contains: quadrates plantae, 4 lumbricales, 4 dorsal interossei, adductor hallucis, flexor

digitorum brevis, & also lateral plantar nerve & vessels.

LATERAL COMPARTMENT

Covered superficially by e thinner lateral plantar fascia. It contains e adductor digiti minimi & flexor digiti minimi brevis.

MUSCLES1ST LAYER 3 muscles: abductor hallucis, flexor digitorum brevis, & abductor digiti minimi.

2ND LAYER 2 muscles & 2 tendons: quadrates plantae, lumbricals (4), tendons of flexor hallucis longus & flexor digitorum longus.

3RD LAYER 3 muscles: flexor hallucis brevis, adductor hallucis, & flexor digiti minimi brevis.

4TH LAYER 2 muscles & 2 tendons: dorsal interossei (4), plantar interossei (3), & tendons of tibialis posterior & fibularis longus.

INNERVATION Medial plantar nerve: abductor hallucis, flexor hallucis brevis, flexor digitorum brevis, & 1st

lumbrical. Lateral plantar nerve: others.

LIGAMENTS

LONG PLANTAR LIGAMENT

Maintains e arches of e foot especially e lateral arch. Attachment is from e plantar surface of e calcaneus to e groove on e cuboid bone & bases of

lateral 3 metatarsals (forming a tunnel for e tendon of e FL).

SHORT PLANTAR LIGAMENT

Also known as plantar calcaneocuboid ligament. Located b/w e long plantar ligament & spring ligament. It extends from e anterior aspect of e inferior surface of e calcaneus to e inferior surface of e

cuboid. Involved in maintaining e longitudinal arch of e foot.

SPRING LIGAMENT

Also known as plantar calcaneonavicular ligament. It is a dense fibroelastic ligamnent. It extends from anterior surface of sustancular tali to tuberosity & inferior surface of

navicular bone. Functions:

1. It helps in maintaining e longitudinal arches of e foot especially e medial arch.2. It supports e head of talus & medial longitudinal arch, a spring-like action when walking.3. It is important in e transfer of weight from e talus.

E superior surface is covered with fibrocartilage.

ARCHES

MEDIAL ARCH Formed by e calcaneus, talus, navicular, & 3 cuneiforms, & 3 metatrsals. Strengthened by TA & fibularis longus tendon.

LATERAL ARCH Formed by e calcaneus, cuboid, & 2 metatarsals. It is much > flatter than e medial arch & rests on e ground during standing.

TRANSVERSE ARCH

Formed by e cuboid, cuneiforms, & bases of metatarsals. Its curvature is maintained by e tendons of FL & TP.

OTHERS

Functions of arches:1. Allows e foot to hold up weight.2. Acts as shock absorbers & springboards for propelling during walking, running, &

jumping.3. E resilient arches add to e foot’s ability to adapt to change in surface contour.

Mechanisms of arch support:1. Passive factors:

a. E shape of e united bones.b. 4 successive layers of fibrous tissue that bowstring e longitudinal arches:

i. Plantar aponeurosis.ii. Long plantar ligament.iii. Short plantar ligament.iv. Spring ligament.

2. Dynamic factors:a. Active (reflexsive) bracing action of intrinsic muscles of foot.b. Active & tonic contraction of muscles with long tendons extending into foot:

i. Flexor hallucis & digitorum longus for e longitudinal arches.ii. Fibularis longus & tibialis posterior for e transverse arch.

APPLIED ANATOMY1. E arches of foot:

Weakness of one or more of e factors that maintain arches can lead to e collapse of these arches & results in a flat foot.

This leads to pain during long periods of standing, walking, & running d/t tremendous pressure on foot.2. Plantar reflex or Babinski response:

Consists of dorsal flexion of e great toe & plantar flexion of other digits. E Babinski sign:

Test: stroke e lateral aspect of e sole of each foot with e end of a reflex hammer or key & note e movement of e toes.

+ve sign: UMN lesion. Exception: normally happens in children under 4 years because e corticospinal tracts e not fully developed

yet.3. Foot deformities:

a. Equinus: foot point downward.b. Calcaneus: calcaneus down.c. Pes planus: flat feet d/t flattened arches.d. Pes cavus: high arches because arches r exaggerated.e. Clubfoot: talipes equinovarus – plantar flxion, inversion, adduction, & supinated with inverted heel.f. Varus: foot deviates towards midline (inversion, adduction, & supination).g. Valgus: foot deviates away from midline (eversion, abduction, & pronation).h. Hallux valgus: valgus deformity at 1st metatarsophalanges joint (e great toe).

PLANTAR FASCIA

THE DISTANCE BETWEEN A PROBLEM AND ITS SOLUTION IS THE DISTANCE BETWEEN THE

KNEE AND THE FLOOR. WHOEVER KNEELS TO ALLAH CAN STAND UP FOR EVERYTHING.

BONES OF THE UPPER LIMB

BONES DETAILS

PECTORAL GIRDLE

CLAVICLE

A colar bone which connect e upper limb to e trunk via sternoclavicular joint. It has no medullary (marrow) cavity, only consists of spongy bone with a shell of compact bone. It is e 1st bone to ossify (5th week of intrauterine life), but e last one to fuse (26 – 30 years). E only long bone pierced by subcutaneous nerve. It has 2 ends:

1. Sternal end: medial, large & rounded end where it articulates with e sternum at sternoclavicular joint.

2. Acromial end: lateral & flat end where it articulates with e acromion of e scapula at acromioclavicular joint.

It has 2 surfaces:1. Superior surface: smooth surface which lies just deep to skin & platysma in e subcutaneous

tissue.2. Inferior surface: rough surface because strong ligaments bind it to e 1st rib near its sterna end

& suspend e scapula from its acromial end. It has 2 curves:

1. E medial 2/3 of e shaft of clavicle is convex anteriorly.2. E lateral 1/3 of e shaft of e clavicle is concave anteriorly.

Other structures on clavicle:1. Conoid tubercle: gives attachment for conoid ligament.2. Trapezoid line: gives attachment for trapezoid ligament.3. Subclavian groove: located in e medial third of e shaft of e clavicle for e attachment of

subclavius muscle.4. Impression for e costoclavicular ligament: a rough, often depressed, oval area that gives

attachment to e ligament binding e 1st rib to e clavicle to limit e elevation of e shoulder. Functions:

1. To act as a strut for holding e upper limb free from e trunk so it may have maximum freedom of action.

2. To provide attachment for muscles.3. To allow passage & protection to e neurovascular bundle.4. To transmit forces from e upper limb to e axial skeleton.

SCAPULA

A triangular flat bone (shoulder blade) that lies on e posterolateral aspect of e thorax, overlying e 2nd – 7th ribs.

E head of e scapula is e thickest part of e bone in e truncated lateral border of scapula. E body of scapula is thin & translucent superior & inferior to e scapular spine. E neck of e scapula is e shallow constriction b/w e head & e body of e scapula. 2 surfaces:

1. Anterior surface: a concave costal surface which forms a large subscapular fossa.2. Posterior surface: a convex surface which is unevenly divided by a thick projecting ridge of

bone, e spine of scapula into a small supraspinous fossa & a much larger infraspinaous fossa. 3 angles: superior, lateral, & inferior angles. 3 borders: medial (vertebral border), lateral (axillary border), & superior borders. 3 bony processes:

1. E spine: a thick projecting ridge of bone at e posterior surface of e scapula.2. E acromion: a flat expanded bony projection which forms e subcutaneous point of e shoulder &

articulates with e acromial end of e clavicle.3. E coracoids process: a beak-like bony projection which is superior to e glenoid cavity &

projects anterolaterally. Other structures on e scapula:

1. E deltoid tubercle of e scapular spine: e prominence indicating e medial attachment of e deltoid.

2. E glenoid cavity: a shallow, concave, & oval fossa directed anterolaterally & slightly superiorly which receives & articulates with e head of e humerus at glenohumeral junction.

3. E suprascapular notch: a notch located at an area where e superior border joins e base of e coracoids process, near e junction of e medial 2/3 & lateral 1/3.

ARM: HUMERUS E largest & longest bone of e upper limb which articulates with e scapula at e glenohumeral join & e radius & ulna

at elbow joint. E parts of e humerus:

1. E proximal end:a. E head: a spherical head which articulates with e glenoid cavity of e scapula. b. E neck:

E anatomical neck: formed by e groove circumscribing e head & separating it from e lesser & greater tubercle. It indicates e line of attachment of e glenohumeral joint capsule.

E surgical neck: a narrow part distal to e head & tubercles which is a common site for fracture.c. E greater & lesser tubercles:

E greater tubercle is at e lateral margin of e humerus while e lesser tubercle projects anteriorly from e bone.

Indicate e junction of e head & e neck with e shaft of e humerus which provide e attachment & leverage to some scapulohumeral muscles.

2. E shaft (concave forwards & convex to e lateral side): Cylindrical in upper half & triangular on cross section in lower half. Has 3 borders: anterior, lateral, & medial (roughened strip a little below e middle).

a. E deltoid tubercle: located laterally for e attachment of e deltoid muscle.b. E radial groove: oblique & spiral groove located posteriorly in which e radial nerve & deep artery of e arm lie

as they pass anterior to e long & b/w e medial & lateral heads of triceps brachii muscle.c. Supraepicondylar ridges & epicondyles: prominent features for muscle attachment.

3. E distal end (much wider):a. Trochlea: a medial, spool-shaped or pulley like surface for e articulation with e proximal end of e ulna.b. Capitulum: a lateral surface for e articulation with e head of e radius.c. Olecranon fossa: a fossa located posteriorly which accommodates e olecranon of e ulna during full extension

of e elbow.d. Radial fossa: a shallower fossa located superior to e edge of e capitulum anteriorly to accommodate e head

of e radius when forearm is fully flexed.e. Coronoid fossa: receives e coronoid process of e ulna during full flexion of e elbow.

FOREARM

ULNA

E stabilizing bone of e forearm which is e medial & longer of e 2 forearm bones. E proximal end of e ulna (> massive & is specialized for articulation with humerus proximally &

radius laterally):1. E olecranon: projects proximally from its posterior aspect & serves as a short lever for

extension of e elbow.2. E coronoid process: projects anteriorly.3. E trochlear notch: formed by e olecranon & e coronoid process.4. E ulnar tuberosity: located inferior to e coronoid process for e attachment of e tendon of e

brachialis muscle.5. E radial notch: a smooth & rounded concavity which receives e broad periphery of e head of e

radius. 6. E supinator crest: a prominent ridge located inferior to e radial notch on e lateral surface of e

ulnar shaft.7. E supinator fossa: a concavity located b/w e supinator crest & e distal part of e coronoid

process for e attachment of supinator muscle. E shaft or body of ulna: is thick & cylindrical proximally, but tapers & diminishing in diameter

distally. E distal end of e ulna:

1. Head of ulna: a small, disk-like, & abrupt enlargement at e narrow distal end of ulna.2. Ulnar styloid process: a small & conical process which projects distally about 1 cm proximal to

e radial styloid process.

RADIUS

E lateral & shorter of e 2 forearm bones which is expanded upper & lower end but lower is wider, head in upper end.

E proximal end of e radius:1. E head: articulates superiorly with e humerus & peripherally with e ulna which is covered with

articular cartilage. 2. E neck: a constriction distal to e head.3. E radial tuberosity: an oval part which is distal to e medial part of e neck & demarcates e

proximal end of e radius from e shaft. E shaft or e body of e radius:

1. E ulnar notch: accommodates e head of ulna.2. E radial styloid process: a ridge-like process in e lateral side of e distal end of e radius.3. E dorsal tubercle: a dorsal projection which lies b/w shallow grooves for e passage of e

tendons of forearm muscles. 4. 3 borders: anterior, posterior, & interosseous borders.5. 3 surfaces: anterior, posterior, & lateral surfaces.

E inferior surface of e distal end of e radius is smooth & concave where it articulates with e wrist or carpal bone.

THE HAND1. 8 carpal bones (from lateral to medial):

1st proximal row: scaphoid, lunate, triquetrum, & pisiform. 2nd distal row: trapezium, trapezoid, capitates, & hamate.

She looks to pretty, try to catch her.2. 5 metacarpal bones: e skeleton of e palm.

3. 14 phalanges.

APPLIED ANATOMY1. Clavicle:

a. Fractures: Common site is e junction of e medial 2/3 & its lateral third. Cause: results of fall on e outstretched hand where e proximal end is pulled upward by sternocledomastoid

muscle. Displaced clavicle fractures can injure major underlying vessels, lung, & brachial plexus.

b. Ossification: 1st bone to ossify, most by intramembranous ossification except at e ends which r endochondral.2. Scapula: winging of scapula.3. Humerus:

a. Carrying angle: e orientation of e forearm in reference to e humerus when e elbow is fully extended. Man: 10o & women: 13o.

b. Tennis elbow or lateral epicondylitis: a tendinitis of e muscle called e extensor carpi radialis brevis which attaches to e lateral epicondyle of e humerus.

c. Golfer elbow or medial epicondylitis: inflammation at e medial epicondyle. d. Ossification:

E head & tubercles fused at 6th year. E head & tubercles fused with shaft at 20th year in males & 18th year in females. Full fusion of e centres occurs at 14th in females & 17th in males.

4. Radius:a. Colles’ fracture: distal metaphysical fracture with dorsal replacement & angulation, radial angulation, & radial

shortening.b. Smith’s fracture: distal metaphysical fracture with volar displacement & angulation.c. Barton’s fracture: fracture of e distal radius associated with dislocation of e carpus.

Allah Sayang Sangat Dengan Kita!!!“Sesungguhnya bersama kesulitan ada kemudahan.

Maka apabila kau telah selesai (dari sesuatu urusan), tetaplah bekerja keras untuk urusan yang

lain. Dan hanya kepada Tuhanmulah engkau berharap.”

PECTORAL REGION

PORTION DETAILS

MUSCLE ORIGIN INSERTION NERVE SUPPLY ACTIONS

ROTATOR CUFF MUSCLESThe main function is to hold the head of the humerus in the glenoid cavity of the scapula.

SUPRASPINATUS Supraspinous fossa of scapula.

Superior facet of greater tubercle of

humerus.

Suprascapular nerve: C4, C5, & C6.

1. Initiates & assists deltoid in abduction

of arm.2. Acts with rotator cuff

muscles.

INFRASPINATUS Infraspinous fossa of scapula.

Middle facet of greater tubercle of

humerus.

Suprascapular nerve: C5 & C6.

1. Laterally rotate arms.

2. Help hold head of humerus in glenoid

cavity.TERES MINOR Middle part of lateral border of scapula.

Inferior facet of greater tubercle of

humerus.

Axillary nerve: C5 & C6.

SUBSCAPULARIS Subscapular fossa. Lesser tubercle of humerus.

Upper & lower subscapular nerve:

C5, C6, & C7.

1. Medially rotates & adducts arms.

2. Help hold head of humerus in glenoid

cavity.

PECTORAL MUSCLES

PECTORALIS MAJOR

1. Clavicular head: anterior

surface of medial half of clavicle.

2. Sternocostal head: anterior

surface of sternum & sup. 6 costal

cartilages.

Lateral lip of bicipital groove of humerus.

Lateral & medial pectoral nerves:

1. Clavicular head: C5 & C6.

2. Sternocostal head: C7, C8, & T1.

1. Adducts & medially rotates humerus.

2. Draws scapula anteriorly & inferiorly.

3. Acting alone, clavicular head

flexes humerus while e other extends it.

PECTORALIS MINOR

3rd-5th ribs near their costal cartilages.

Medial border & superior process of

scapula.

Medial pectoral nerve: C8 & T1.

Stabilizes scapula by drawing it inferiorly &

anteriorly against thoracic wall.

SUBCLAVIUS Junction of 1st rib & its costal cartilage.

Inferior surface of middle third of

clavicle.

Nerve to subclavius: C5 & C6.

Anchors & depresses clavicle.

SERRATUS ANTERIOR

External surfaces of lateral parts of 1st-8th

rib.

Anterior surface of medial border of

scapula.

Long thoracic nerve: C5, C6, & C7.

1. Protracts scapula & holds it against thoracic wall.

2. Rotates scapula.

FASCIAE OF E UPPER LIMB1. Pectoral fascia:

Invests e pectoralis major & is continuous inferiorly with e fascia of e anterior abdominal wall. Leaves e lateral border of pectoralis major & becomes e axillary fascia.

2. Clavipectoral fascia: Located deep to e pectoral fascia & pectoralis major. Descends from e clavicle to enclose e subclavius & pectoralis minor & continues inferiorly with axillary fascia. Its part b/w subclavius & pectoralis minor is called costocoracoid membrane which is pierced by lateral pectoral

nerve. Its part inferior to pectoralis minor is called e suspensory ligament of e axilla which supports e axillary fascia &

pulls it & e skin inferior to it upward during abduction of e arm, forming e axilary fossa.3. Supraspinous & infraspinous fascia: overlying e supraspinatus & infraspinatus muscles respectively. Their posterior

aspects on e scapula r so dense & opaque.4. Brachial fascia:

A sheath of deep fascia which encloses e arm deep to e skin & subcutaneous tissue. It is continuous superiorly with deltoid, pectoral, axillary, & infraspinatus fasciae. It is attached inferiorly to e epicondyles of e humerus & e olecranon of e ulna & continuous with e deep fascia of e

forearm. Its deep surface extends to e central shaft & medial & lateral supraepicondylar ridges of e humerus to become

medial & lateral intermuscular septa which divide e arm into anterior & posterior fascial compartment.

OTHERS1. Deltopectoral groove:

A groove located b/w pectoralis major & deltoid muscles. A passageway where cephalic vein runs.

2. Clavipectoral triangle: A triangle located b/w deltoid muscle & pectoralis major muscle (sternocostal head only). E contents:

a. Thoracoacromial artery & pectoral nerve: existing e axilla.

b. E cephalic vein: entering e axilla.

Kadangkala Allah hilangkan mentari……Kemudian Dia datangkan guruh

Puas kita menangis……Mencari mana mentari kita

Rupa-rupanya Allah nak hadiahkan kita pelangi indah…

THE AXILLA

PORTION DETAILS

OVERVIEW

E axilla is e pyramidal space inferior to e glenohumeral joint & superior to e axillary fascia at e junction of arm & thorax.

It provides a passageway or distribution centre for e neurovascular structures that serve e upper limb.

Proximally, these neurovascular stryctures r ensheathed in a sleeve-like estension of e cervical fascia called e axillary sheath.

From here, e neurovascular structures pass:1. Superiorly via cervicoaxilary canal to e root of e neck.2. Anteriorly via e clavipectoral triangle to e pectoral region.3. Inferiorly & laterally into e limb itself.4. Posteriorly via quadrangular space to e scapular region.5. Inferiorly & medially along e thoracic wall to e inferiorly placed axioappendicular muscles.

BOUNDARIES

APEX

E apex of axilla is e cervicoaxillary canal: e passageway b/w e neck & axilla. It is bounded by:

1. 1st rib medially. 2. Clavicle anteriorly.3. Superior edge of scapula posteriorly.

BASE

It is formed by e concave skin, subcutaneous tissue, & axillary fascia extending from e arm to e thoracic wall to form e axillary fossa which is bounded by e anterior & posterior axillary folds, e thoracic wall, & e medial aspect of e arm.

Also called as armpit which contains axillary hair.

ANTERIOR WALL

E anterior wall has 2 layers:1. Layer formed by pectoralis major & pectoral fascia.2. Layer formed by pectoralis minor & clavipectoral fascia.

POSTERIOR WALL

E posterior wall is formed by:1. E scapula & subscapularis muscles on its anterior surface.2. E teres major & latissimus dorsi inferiorly.

MEDIAL WALL

E medial wall is formed by:1. 1st to 4th ribs & intercostal muscles.2. Serratus anterior muscle which covered e thoracic wall.

LATERAL WALL

E lateral wall is a narrow floor of intertubecular sulcus of e humerus which lodges e tendon of e long headof biceps brachii muscle.

FOLDS1. E anterior axillary fold:

E inferiormost part of e anterior wall. Formed by e lateral border of pectoralis major

muscle & e overlying integument.

2. E posterior axillary fold: E inferiormost part of e posterior wall. It extends farther inferiorly than e anterior wall. It is formed by teres major, latissimus dorsi, & overlying

integument.

CONTENTS

AXILLARY ARTERY

It begins at e lateral border of e 1st rib as e continuation of subclavian artery, then it passes posterior to e pectoralis minor into e arm & ends at e inferior border of e teres major as e brachial artery.

It is divided into 3 parts by e pectorals minor muscle:1. 1st part of axillary artery:

Located b/w e lateral border of 1st rib & e medial border of pectoralis minor & enclosed in e axillary sheath.

Has only 1 branch i.e. superior thoracic artery which supplies:a. Subclavius muscles.b. Muscles in e 1st & 2nd intercostals space.c. Superior slips of e serratus anterior.d. Pectoral muscles.

2. 2nd part of e axillary artery: Lies posterior to e pectoralis minor. Has 2 branches:

a. Thoracoacromial artery: pierces e costocoracoid membrane. b. Lateral thoracic artery: pectoral, serratus anterior, & intercostals muscles, axillary LN, &

lateral breast.3. 3rd part of e axillary artery:

Extends from e lateral border of pectoralis minor to e inferior border of e teres major. Has 3 branches:

a. Subscapular artery: subscapularis.b. Anterior & posterior circumflex humeral arteries: muscles on e dorsum of e scapula.

AXILLARY VEIN

It lies initially on e anteromedial side of e axillary artery, with its terminal part anteroinferior to e artery.

It is formed by e union of brachial vein & basilic vein at e inferior border of teres major & ends at e lateral border of e 1st rib where it becomes e subclavian vein.

It is highly abundant, variable, frequently anastomose & receives e thoracoepigastric veins which constitute a collateral route that enable venous return in e presence of obstruction of e IVC.

AXILLARY LYMPH NODES

There r 5 groups of axillary LN which r arranged in a manner that reflects pyramidal shape of axilla:1. Pectoral or anterior LN: 3 or 5 LN that lie along e medial wall of axial around e lateral thoracic

vein & anterior border of pectoralis minor. They drain e anterior thoracic wall.2. Subscapular or posterior LN: 6 or 7 LN that lie along e posterior axillary fold & subscapular

blood vessels.3. Humeral or lateral LN: 4 to 6 LN along e lateral wall of axilla, medial & posterior to e axillary

vein which drains e posterior thoracic wall.4. Central LN: 3 to 4 LN located deep to e pectoalis minor near e base of axilla which receives all

e 3 previous LN.5. Apical LN: located at e apex of e axilla along e medial side of e axillary vein & e 1st part of

axillary artery. It receives e central LN, then unite to form e seubclavian lymphatic trunk.

THE ARM

PORTION DETAILS

MUSCLE ORIGIN INSERTION NERVE SUPPLY ACTION

ANTERIOR COMPARTMENT

BICEPS BRACHII

1. Short head: tip of coracoids process

of scapula.2. Long head:

supraglenoid tubercle of scapula.

Radial tuberosity.

Musculocutaneous nerve: C5 & C6.

1. Supinates forearm, & when it is

supine, flexes forearm.

2. Short head resists dislocation of

shoulder.

BRACHIALIS Distal half of anterior surface of humerus.

1. Coronoid process.2. Ulna tuberosity.

Flexes forearm in all position.

CORACO-BRACHIALIS

Tip of coracoid process of scapula.

Middle third of medial surface of humerus.

1. Helps flex & adduct arm.

2. Resists dislocation of shoulder.

POSTERIOR COMPARTMENT

TRICEPS BRACHII

1. Long head: infraglenoid tubercle of scapula.

2. Lateral head: posterior surface

of humerus, superior to spiral

groove.3. Medial head: posterior surface

of humerus, inferior to spiral

groove.

Posterior end of olecranon of e ulna.

Radial nerve: C6, C7, & C8.

1. Chief extensor of forearm.

2. Long head resists dislocation of

humerus.3. Abduction.

SPACES IN POSTERIOR COMPARTMENT

QUADRANGULAR SPACE

E boundaries:1. Superior: teres minor.2. Inferior: teres major.3. Lateral: humerus.4. Medial: lateral head of triceps

brachii. E contents:

1. Axillary nerve.2. Posterior circumflex humeral

artery.

TRIANGULAR SPACE

E boundries:1. Superior: teres minor.2. Inferior: teres major.3. Lateral: lateral head of triceps

brachii. E content: circumflex scapular

artery.

BLOOD & NERVE SUPPLY

Blood supply: brachial artery.Nerve supply: median, ulnar, & musculocutaneous nerves.

NERVES RELATED TO HUMERUS

AXILLARY NERVE Located at e surgical neck of e humerus. Shoulder joint dislocation: axillary nerve injury. Badly adjusted crutch: axillary nerve palsy.

RADIAL NERVE Located at e spiral groove of e humerus together with profunda brachial artery & its venae

Triangular space

Quadrangular space

Teres

Teres

Humer

LH of triceps

commitantes. Crutch palsy or Saturday night palsy: radial nerve injury. Fracture & dislocation of proximal end of humerus.

ULNAR NERVE Located at e medial epicondyle of e humerus. Fracture of e lower end of humerus: ulnar nerve injury.

“Ketahuilah, dengan mengingati Allah itu, maka tenang tenteramlah hati

manusia.” (13:28)

Posterior compartment

Anterior compartment

Lateral view

Deltoid muscle

Biceps brachii muscle

Triceps brachii muscle

Circumflex scapular artery

Triangular space

Posterior circumflex artery & axillary nerve

Quadrangular space

Lateral head of triceps brachii

muscle

Deltoid muscle

Biceps brachii muscle

Triceps brachii muscle

Ulnar nerve

SHOULDER JOINT

PORTION DETAILS

TYPE Synovial joint & ball & socket variety.

BONES 1. Socket: shallow glenoid cavity of scapula.2. Ball: hemispherical head of humerus.

CAPSULE

Fibrous capsule: Attached to scapula: just proximal to e margin of glenoid cavity. Attached to e humerus: at e anatomical neck.

2 openings: Passage for long head of biceps brachii. Lies anteriorly below e coracoids process & allows communication b/w joint & subscapular

bursa.

LIGAMENTS

1. Gleno-humeral ligament: These are thickenings of e anterior part of e fibrous capsule. E superior, middle, & inferior glenohumeral ligaments run from e supraglenoid tubercle of e

scapula to e lesser tubercle and e anatomical neck of e humerus.2. Accessory ligament:

a. Coraco-humeral ligament: This is a strong, broad band that strengthens e superior part of e capsule of e shoulder

joint. It passes from e lateral side of e base of e coracoid process of e scapula to e

anatomical neck of e humerus, adjacent to e greater tube.b. Transverse humeral ligament:

This is a broad band of transverse fibers passing from e greater to e lesser tubercles of e humerus.

It forms a bridge over e superior end of e intertubercular groove, converting it into a canal that holds e synovial sheath & e tendon of e long head of e biceps as they emerge from e capsule of e shoulder joint.

c. Coraco-acromial ligament: This is a strong triangular ligament, e base of which is attached to e lateral border of e

coracoid process. Its apex is inserted into e edge of e acromion. Superiorly, the coracoacromial ligament is covered by e deltoid muscle.

d. Glenoidal labrum: a fibrous cartilaginous rim whose superior portion blends with e tendon of e long head of the biceps brachii muscle.

BURSAE

1. Subscapular bursa: This bursa lies b/w e tendon of e subscapularis muscle & e neck of e scapula. E bursa protects this tendon where it passes inferior to e root of e coracoid process & over

e neck of e scapula. It usually communicates with e cavity of e shoulder joint through an opening in its fibrous

capsule; thus it is really an extension of e cavity of e shoulder joint.2. Subacromial bursa:

This is a larger bursa that lies b/w e deltoid muscle, e supraspinatus tendon, & e fibrous capsule of e shoulder joint. Its size varies, but it does not normally communicate with e cavity of e shoulder joint.

E subacromial bursa is located inferior to e acromion and e coracoacromial ligament, b/w them & e supraspinatus muscle.

INTRA-CAPSULAR

STRUCTURES

E synovial membrane lines e non-articular surfaces of e joint. It also forms a tubular sheath for e tendon of biceps brachii. It protrudes forwards through e anterior wall of e capsule to form e subscapularis bursa, which

lies beneath e subscapularis muscle.

RELATIONS

1. Anterior: subscapularis muscles & bursa.2. Posterior: infraspinatus & teres minor muscles.3. Superior: supraspinatus muscle, subacromial bursa, & coraco-acromial arch.4. Inferior: long head of triceps brachii & axillary nerve.5. Interior: tendon of briceps brachii (long head).6. Lateral: deltoid muscle which embrace e joint.

STABILITY

1. Rotator cuff muscles:a. Supraspinatus muscle & coracoacromial arch guard e shoulder joint superiorly.b. Infraspinatus & teres minor muscles stabilize e joint inferiorly (but not so strong).c. Subscapularis muscle: protects e joint anteriorly.

2. Ligaments: as stated above.3. Exception: joint capsule is weaken inferiorly because no tendons support it inferiorly. Thus,

downward dislocation is more likely to occur.

BLOOD & NERVE SUPPLY

Blood supply:1. Anterior & posterior circumflex humeral

arteries from axillary artery.2. Suprascapular artery from subclavian

artery.

Nerve supply:1. Axillary nerve.2. Suprascapular nerve.3. Lateral pectoral nerve.

MOVEMENT 1. Flexion: biceps bachii, coracobrachialis, deltoid (clavicular head), & pectoralis major muscles.2. Extension: deltoid (posterior head), latissimus dorsi, trapezius, & levator scapulae muscles.3. Abduction: supraspinatus muscle (initial 15o), deltoid muscle (middle head- up until 90o), &

serratus anterior muscle (above 90o).

4. Adduction: latissimus dorsi, pectoralis major, & teres major muscles.5. Medial rotation: latissimus dorsi, pectoralis major, teres major, subscapularis, & deltoid

muscles (posterior head).6. Lateral rotation: infraspinatus, teres minor, & deltoid muscles (posterior head).

APPLIED ANATOMY

1. Dislocation (subluxation) of shoulder joint: > often dislocated d/t great freedom of movement & instability of joint. Axillary nerve may be damaged in downward dislocation of humerus.

2. Calcific supraspinatus tendonitis: may cause pain during abduction of shoulder joint.3. Kinking of axillary artery: d/t extremely mobile joint which can lead to arterial occlusion &

thrombosis.

THE FOREARM

PORTION DETAILS

MUSCLE ORIGIN INSERTION NERVE SUPPLY ACTION

ANTERIOR COMPARTMENT: FLEXORSUPERFICIAL GROUP

PRONATOR TERES

1. Ulnar head: coracoids process.

2. Humeral head: medial epicondyle

(CFO).

Middle of convexity of lateral surface of

radius. Median nerve: C6 & C7.

Pronates & flexes forearm.

FLEXOR CARPI RADIALIS

Medial epicondyle or common flexor origin,

CFO.

Base of 2nd

metacarpalFlexes & abducts

hand at wrist joint.

PALMARIS LONGUS

Distal half of flexor retinaculum & apex of palmar aponeurosis.

Median nerve: C7 & C8.

1. Flexes hand at wrist joint.

2. Tenses palmar aponeurosis.

FLEXOR CARPI ULNARIS

1. Humeral head: medial epicondyle

of CFO.2. Ulnar head:

olecranon process.

1. Pisiform.2. Hook of hamate.3. 5th metacarpal.

Ulnar nerve: C7 & C8.

Flexes & adducts hand at wrist joint.

FLEXOR DIGITORUM

SUPERFICIALIS

1. Humeroulnar head: medial

epicondyle or CFO & coronoid process.

2. Superior half of anterior border.

Shafts of middle phalanges of medial 4

digits.

Median nerve: C7, C8, & T1.

1. Flexes middle phalanges at

proximal interphalangeal

joints.2. Flexes proximal

phalanges at metacarpophlange

al joints.

DEEP GROUP

FLEXOR DIGITORUM PROFUNDUS

Proximal 3 quarters of medial & anterior surfaces of ulna &

interosseous membrane.

Bases of distal phalanges of 4th & 5th

fingers.

1. Medial part: ulnar nerve: C8 & T1.

2. Lateral part: anterior

interosseous nerve: C8 & T1.

Flexes distal phalanges at distal

interphalangeal joints.

FLEXOR POLICIS LONGUS

Anterior surface of radius & adjacent

interosseus membrane.

Base of distal phalanx of tumbs.

Anterior interosseous nerve: C8 & T1.

Flexes phalanges of 1st digit.

PRONATOR QUADRATUS

Distal quarter of anterior surface of

ulna.

Distal quarter of anterior surface of

radius.Pronates forearm.

BLOOD SUPPLY Superficial group: radial & ulnar arteries. Deep grop: anterior interosseous artery.

POSTERIOR COMPARTMENT: EXTENSORSUPERFICIAL GROUP

BRACHIO-RADIALIS

Supraepicondylar ridge of humerus.

Lateral end of distal end of radius proximal

of styloid process. Radial nerve: C5, C6, & C7.

Flexion of e forearm.

EXTENSOR CARPI RADIALIS LONGUS

Lateral supraepicondylar ridge of humerus.

Dorsal aspect of base of 2nd metacarpal. Extend & abduct hand

at e wrist joint.EXTENSOR CARPI RADIALIS BREVIS

Lateral epicondyle of humerus: common

extensor origin, CEO.

Dorsal aspect of base of 3rd metacarpal.

Deep branch of radial nerve: C7 & C8.

EXTENSOR Extensor expansions Posterior Extends medial 4

DIGITORUM of medial 4 fingers.

interosseous nerve: C7 & C8.

fingers at:1. 1o: metacarpo-

phalangeal joints.2. 2o: inter-

phalangeal joints.

EXTENSOR DIGITI MINIMI

Extensor expansion of 5th finger.

Extends 5th finger at:1. 1o: metacarpo-

phalangeal joints.2. 2o: inter-

phalangeal joints

EXTENSOR CARPI ULNARIS

Dorsal aspect of base of 5th metacarpal.

Extends & adducts hand at wrist joint.

ANCONEUS

Lateral surface of olecranon & superior

part of posterior surface of ulna.

Radial nerve: C7, C8, & TI.

1. Assists triceps in extending forearm.

2. Stabilizes elbow joint.

3. Abduct ulna during pronation.

DEEP GROUP

ABDUCTOR POLLICIS LONGUS

Posterior surface of proximal halves of

ulna, radius, & interosseous membrane.

Base of 1st

metacarpal.

Posterior interosseous nerve:

C7 & C8.

Abducts thumb & extends at

carpometacarpal joint.

EXTENSOR POLLICIS BREVIS

Posterior surface of distal third of radius

& interosseous membrane.

Dorsal aspect of base of proximal phalanx of

thumb.

1. Extends proximal phalanx of thumb

at metacarpophalang

eal joint.2. Extends

carpometacarpal joint.

EXTENSOR POLLICIS LONGUS

Posterior surface of middle third of ulna &

interosseous membrane.

Dorsal aspect of base of distal phalanx of

thumb.

1. Extends distal phalanx of thumb at interphalangeal

joint.2. Extends

metacarpophlangeal &

carpometacarpal joint.

EXTENSOR INDICIS

Posterior surface of distal third of ulna &

interosseous membrane.

Extensor expansion of 2nd finger.

Extends 2nd finger & extends hand at wrist

joint.

SUPINATOR Lateral epicondyle of humerus: CEO.

Lateral posterior & anterior surfaces of

proximal third of radius.

Deep branch of radial nerve: C7 & C8.

1. Supinates forearm.2. Rotates radius to

turn palm anteriorly or superiorly.

BLOOD SUPPLY Ulnar artery → common interosseous artery → posterior & anterior interosseous arteries.

ANATOMICAL SNUFF BOX E anatomical snuff box is visible when e thumb is fully extended because this position draws e tendons up &

produces a triangular hollow b/w them. Boundaries:

1. Anteriorly: e tendons of abductor pollicis longus & extensor pollicis brevis.2. Posteriorly: e tendon of extensor pollicis longus.3. Floor:

a. Radial styloid process can be palpated proximally & e base of e 1st metacarpal can be palpated distally in e snuff box.

b. Scaphoid & trapezium can be felt in e floor of e snuff box b/w e radial styloid process & e 1st metacarpal. Contents: radial artery lies in e floor of e snuff box.

CUBITAL FOSSA

PORTION DETAILS

SHAPE & SITE

It is seen superficially as a depression on e anterior aspect of e elbow. E fossa is triangular in shape. It is a space filled with fats anterior to e most distal part of e humerus & e elbow joint.

BOUNDARIESLATERAL Brachioradialis muscle.

MEDIAL Pronator teres muscle.

BASE Imaginary line drawn b/w e 2 humeral epicondyles.

ROOF

1. Skin & subcutaneous tissue.2. Superficial fascia: lateral & medial cutaneous nerves of e forearm & median cubital vein.3. Deep fascia: e continuity of brachial & antebrachial fascia reinforced by e bicipital

aponeurosis.

FLOOR1. Supinator muscle.2. Brachialis muscle.3. Capsule of e elbow joint.

CONTENTS1. Fat.2. Median nerve.3. Brachial artery & its venae commitantes.4. Tendon of biceps.

5. Radial nerve.6. Terminal branches of radial nerve.7. Terminal branches of brachial artery.

THE ELBOW JOINT

PORTION DETAILS

TYPE & BONES

It is a synovial joint with hinge or ginglymus variety. It is composed of:

1. Lower end of humerus: trochlea & capitulum.2. Upper end of radius & ulna: proximal surface of radius & trochlear notch of ulna.

It is a uniaxial joint whose movement consists of flexion & extension.

ARTICULATIONS

1. E humeroulnar articulation: b/w e trochlea of e humerus & e trochlear notch of e ulna. They form a uniaxial hinge joint, permitting movement in one axis: flexion and extension.

2. E humeroradial articulation: b/w e capitulum of e humerus & e head of e radius. E capitulum fits into e slightly cupped surface of e head.

3. E proximal radioulnar joint: b/w e head of e radius & radial notch of e ulna. This is a pivot joint, permitting rotation of e radius about e ulna.

CAPSULE

1. Superiorly: attaches around e upper boundaries of e olecranon, coronoid, & radial fossae on e humerus & to its articular margin medially & laterally.

2. Inferiorly: attaches to e olecranon & coronoid processes at e medial edge of e trochlear notch.

3. Laterally: blends with e upper border of e annular ligaments of e proximal radio-ulnar joint.

4. E fibrous capsule completely encloses e joint. Its anterior & posterior parts r thin & weak, but collateral ligaments strengthen its sides.

LIGAMENTS

1. Radial collateral ligament: Its apex is attached proximally to e lateral epicondyle of e humerus & its base blends with e anular ligament of e radius.

2. Medial collateral ligament: It is composed of anterior & posterior bands, which r connected by a thinner &

relatively weak oblique band. Its apex is attached to e medial epicondyle of the humerus. E strong cord-like anterior part is attached to e tubercle on e coronoid process of e

ulna and e weaker fan-like posterior part is attached to e medial edge of e olecranon. E ulnar nerve passes posterior to e medial epicondyle, is closely applied to e ulnar

collateral ligament & has e posterior ulnar artery ascending close to it.

BURSAE 1. Subcutaneous olecranon: in e subcutaneous connective tissue over e olecranon.2. Subtendinous olecranon: b/w e tendon of e triceps brachii & e olecranon.

INTRA-CAPSULAR

STRUCTURES

1. Synovial membrane: Lines e fibrous capsule & is reflected onto e humerus, lining e coronoid & radial

fossae anteriorly & e olecranon fossa posteriorly. E synovial capsule is continued into e proximal radioulnar joint.

A redundant fold of e synovial capsule, called e sacciform recess, emerges distal to e anular ligament & facilitates rotation of e head of e radius, e.g., during supination & pronation.

2. Pads of fat: Separate synovial membrane from fibrous capsule over olecranon, coronoid, & radial

fossae. Slide into e fossae when e bony processes r withdrawn.

RELATIONS 1. Anterior: cubital fossa & its contents.2. Posterior: triceps brachii muscle.

Anterior compartmentPosterior compartment

Lateral view Anterior view (deep)

Brachioradialis

ECRL

Extensor digitorum

EDM

ECU

Anconeus

Extensor retinaculum

Pronator teres

FCR

Palmaris longus

Radial artery

Ulnar nerve & artery

Pronator teres

FCR

Palmaris longus

Radial artery

Ulnar nerve & artery

Radial artery

Ulnar nerve & artery

Ant. interosseous artery & nerve

Median nerve

3. Medial: common flexor origin & ulnar nerve.4. Lateral: common extensor origin & radial nerve.

MOVEMENT1. Flexion: biceps brachii, brachialis, brachioradialis, ECRL, FCR, & PT.2. Extension: triceps brachii & anconeus.3. Ulnar abduction: anconeus.

STABILITY

1. Adult: Quite stable d/t very strong ulnar & radial collateral ligaments. Hinge-like arrangement: spanner-shape trochlear notch of ulna into which e spool-

shape trochlea of e humerus fits. Of close proximity of brachialis & triceps brachii muscle.

2. Children: not so stable d/t late fusion of e epiphyses of e ends of e bones involved in e articulation.

BLOOD & NERVE SUPPLY

1. Blood anastomoses of elbow joint is formed by:a. Collateral branches of brachial artery.b. Recurrent branches of ulnar & radial arteries.

2. Nerve supply:a. Median nerve. d. Posterior interosseous nerve.b. Ulnar nerve.. e. Musculocutaneous nerve. c. Radial nerve.

APPLIED ANATOMY

1. Related to elbow joint:a. Student’s elbow or Miner’s elbow:

Subcutaneous olecranon bursae is exposed to injury from falls on e elbow & to infection from skin abrasion.

As a result of repeated excessive friction, this bursa may become inflamed, producing a friction bursitis.

b. Pulled elbow: Common injury in preschool children. Sudden jerk or pull results in transient subluxation or dislocation of e head of e

radius.c. Root or segmental values for upper limb movement:

Elbow - flexion: C5 & C6 (biceps brachii). Elbow – extension: C7 & C8 (triceps brachii).

2. Not related to elbow joint:a. Golfer’s elbow:

Relatively uncommon problem presents as pain over e medial epicondyle & is aggravated by extension of elbow in supinated forearm.

It is d/t repetitive strain from any of e common flexor origin muscles.b. Tennis elbow:

There is tenderness over e lateral epicondyle at e elbow joint caused by any repetitive movement.

Involved extensor group of muscles.

THE RADIO-ULNAR JOINT

PROXIMAL JOINT PORTION DISTAL JOINTSynovial joint. TYPE Synovial & pivot joint.

1. Radius head.2. Radial notch of ulna. BONES 1. E head of ulna.

2. E ulnar notch of radius.

Encloses e joint & continuous with that of elbow joint. CAPSULE Encloses e joint but deficient superiorly.

1. Anular ligament: Attached to ulna at e anterior & posterior

margin of radial notch. It is not attached to radius but forms like

colar around e head of radius. It is continuous above with e capsule of

elbow joint.2. Small quadrate ligament: extends b/w neck of

radius & ulna, & just below e radial notch.

LIGAMENTS

1. Weak anteriorly, but posterior ligaments strengthen e capsule.

2. Articular disc is fibrocartilage type & triangular in shape: Apex: at e lateral side of styloid process

of ulna. Base: at e lower border of ulnar notch of

radius. It shuts of e distal radio-ulnar joint from wrist joint & strongly unites radius & ulna.

Continuous above with that of elbow joint just like e cavity of e capsule.

SYNOVIAL MEMBRANE

Lines e interior of e capsule. A pouch projects superiorly in front of

interosseous membrane for a variable distance beyond e joint.

1. Blood supply: e radial portion of e periarticular arterial anastomosis of e elbow joint.

2. Nerve supply: median, ulnar, musculocutaneous, & radial nerves.

BLOOD & NERVE SUPPLY

1. Blood supply: anterior & posterior interosseous arteries.

2. Nerve supply: anterior interosseous nerve & deep branch of radial nerve.

1. Supination & pronation: axis is through e head of radius & styloid process of ulna (180o).a. Supination:

MOVEMENT 1. Pronation & supination: axis passes through e head of radius (above) & apex of articular disc (below).

2. Supination > pronation: screw &

Returns e limb to e anatomical position.

More powerful movement involving biceps brachii & supinator muscles.

b. Pronation: Rotates across e ulna & twist e

forearm & hand so that palm faces posteriorly.

Involved pronator teres & quadrates.2. When elbow is flexed, brachioradialis rotates

e forearm & returns e limb to e midposition from e extremes of supination & pronation.

cockscrews r driven intertwined by supination in Rt. Handed person.

1. Anterior: supinator muscle & radial nerve.2. Posterior: supinator muscle & common

extensor muscles.RELATIONS 1. Anterior: FDP.

2. Posterior: extensor digiti minimi.

Monteggia’s lesion: occurs when e shaft of ulna is forced from behind, producing e anterior

dislocation of radial head & rupture of anular ligament.

APPLIED ANATOMY

Galeazzi’s lesion: proximal 3rd radial lesion & distal end of ulnar dislocation.

THE HAND

PORTION DETAILS

INTRINSIC MUSCLES

THENAR

1. Abductor pollicis brevis.2. Flexor pollicis brevis (superficial & deep head). Nerve supply: recurrent branch of

median.3. Opponens pollicis.

HYPOTHENAR1. Abductor digiti minimi.2. Flexor digiti minimi. Nerve supply: deep branch of ulnar.3. Opponens digit minimi.

LUMBRICALS

Origin: radial side of e flexor digitorum profundus tendons. Insertion: radial side of each of e proximal phalanx & extensor expansion. Action:

1. Flexion at e metacarpophalyngeal joint.2. Extend interphalangeal joints.

Nerve supply:1. 1st & 2nd lumbricals (uni-pinnate) r supplied by median nerve.2. 3rd & 4th lumbricals (bi-pinnate) r supplied by ulnar nerve.

DORSAL INTEROSSEI

Overview: They r 4 in number. 1st & last fingers have their own abductors, so, they don’t need any dorsal abductors. E middle finger is abducted whichever way it goes. Thus, it has 2 dorsal interossie.

Origin: Palmar surface of metacarpal bones & arise by 2 heads from adjacent metacarpal bones.

Insertion: Palmar & dorsal interossie r mainly inserted into extensor expansion. Also into base of appropriate side of proximal phalanx.

Action: dorsal abduction (DAB). Nerve supply: all interossei r supplied by e deep branch of ulnar nerve.

PALMAR INTEROSSEI

Overview: They r 3 in number. Middle finger has no palmar interossei because it cannot be adducted toward itself. Thumb has no palmar interosseous because it already has its own powerful one, adductor

pollicis muscle. Origin: palmar surface of metacarpal bones. Insertion: palmar surface of metacarpal bones. Action: palmar adduction. Nerve supply:deep branch of ulnar nerve.

OTHERS

Adductor pollicis: Transverse & oblique head. Supplied by deep branch of ulnar nerve. It is not a thenar muscle. It lies deep in e palm.

Flexor & extensor synovial sheath r important in hand infection because if little finger has infection, it can spread to all other tendons of other digits.

RETINACULUMFLEXOR

RETINACULUM It is a strong band of tissue attached to:

1. Trapezium & scaphoid on e radial side.2. Hamate & pisiform on e ulnar side.

It lies in e palm of e hand. Properties:

No large arteries pass deep to e retinaculum.

Ulnar nerve & artery pass superficial to e retinaculum so r exposed to possible injury but not to compression.

Median nerve except its palmar branch passes deep to e retinaculum.

EXTENSOR RETINACULUM

Attachment:1. Medially to pisiform & triquetrum bones.2. Laterally to lower part of anterior border of ulna.

CARPAL TUNNEL

ANATOMY

E carpal bones form an anterior concavity or sulcus known as carpal groove which is converted into a tunnel called carpal tunnel by e flexor retinaculum.

Through e tunnel, tendons & e median nerve pass. Contents: tendons of FDS, FDP, FPL, FCR, & median nerve.

CARPAL TUNNEL

SYNDROME

Any lesion that reduces e size of e tunnel will lead to carpal tunnel syndrome which compresses e median nerve.

This will lead to:1. Parasthesia: tingling sensation.2. Anesthesia: absence of sensation. In e digits supplied by e median nerve.3. Hyposthesia: decreased sensation.4. Weak thumb d/t weakness of:

a. Abductor pollicis brevis.b. Oponesis pollicis.

5. 1st 3 fingers lose their normal power & function. Treatment:

1. Medical: anti-inflammatory agents.2. Surgical: partial or complete division of retinaculum.

WRIST JOINT

PORTION DETAILS

TYPE Synovial joint with ellipsoid variety.

BONES

1. Convex proximal surface of e carpus formed by:a. Scaphoid. c. Triquetrum.b. Lunate. d. Interosseous ligaments.

2. Concave socket formed by:a. Distal surface of e radius.b. E triangular articular disc.

CAPSULE Passes from margins of distal ends of radius & ulna & from e margins of articular disc to proximal row of carpal bones, excluding pisiform.

LIGAMENTS

1. Medial or ulnar collateral ligament: attaches to ulnar styloid process & triquetrum.2. Lateral or radial collateral ligament: attaches to radial styloid process & scaphoid.3. Anterior & posterior ligaments:

a. Palmar radiocarpal ligament or radioulnar ligament.b. Dorsal radiocarpal ligament or radioulnar ligament.

INTRACAPSULAR STRUCTURE

1. E synovial membrane: lines e fibrous capsule & covers e interosseous ligament of carpus.

2. E triangular disc: Joins e medial edge of e articular surface of e radius to e styloid process of e ulna. Only on rare occasions when e disc is perforated & e wrist joint will communicate

with e distal radio-ulnar joint.

RELATIONS

1. Anterior: PL, Median nerve, FCR, FPL, FDS, FDP, & Ulnar artery.2. Posterior: EPL, ECRL, ECRB, EI, ED, EDM, & Radial nerve.3. Medial: FCU & ECU.4. Lateral: AbPL, EPB, EPL, Radial artery, & Anatomical snuff box.

MOVEMENT

1. Flexion: FCU, FCR, FDP, FD S/F, FPL, & PL.2. Extension: ECU, ECRL, ECRB, ED, EDM, EPL, & EI.3. Abduction: ECRL, ECRB, FCR, & AbPL.4. Adduction: ECU & FCU.

JOINT STABILITY Mainly dependent on:

1. Ligaments.2. Tendons.

BLOOD & NERVE SUPPLY

1. Blood supply: a. Dorsal carpal arch.b. Palmar carpal arch.

2. Nerve supply:a. Anterior interosseous nerve.b. Posterior interosseous nerve.c. Dorsal branch of ulnar nerve.

APPLIED ANATOMY

1. Colles’ fracture: Also known as wrist fracture. It involves e distal end of e radius. It is e commonest type of fracture seen in persons over 50 years old & occur > in

women. E distal fragment of fractured radius is usually tilted backward & slightly to e

lateral side.

E dorsal displacement produces a characteristic hump described as dinner fork deformity.

2. Smith fracture: Lesion of e fragment of radius. Anteriorly fall on e back of e hand.

3. Wrist drop.4. Radial artery pulsation.5. Lunate dislocation: dorsiflexion of wrist joint.6. Wrist joint’s segmental values:

a. Flexion: C6 & C7.b. Extension: C6 & C7.

THE MAMMARY GLAND

PORTION DETAILS

LOCATION

Superficial fascia of e anterior chest wall which located anterior to e pectoralis major, serratus anterior, & external oblique muscles.

Has no fibrous capsule which aids in e rapid spread of cancer to underlying muscles. E extension:

1. Vertical: 2nd – 6th ribs.2. Horizontal: lateral border of sternum to midaxillary line.

STRUCTURES

1. Nipple: 4th intercostals space, 4’’ from midline. Minute opening of lactiferous ducts &

smooth muscle.2. Areola: pigmented skin surrounding e

nipple.3. Tubercle of Montgomery:

Small bumps around areola. Contains sebaceous gland for lubrication

during nursing.

4. Axillary tail of Spence: Prolongation of normal breast from

upper outer aspect. Enter axilla through Langer’s foramen. Lies in deep fascia of e breast.

5. Retromammary space: Thin layer of loose areolar tissue

consists of fat, lymphatics, & small vessels.

Located b/w breast & pectoralis major muscle.

Allows some degree of movement of e breast.

HISTOLOGY

3 principle tissues:1. Glandular tissue: 15 – 20 lobes.2. Fibrous stroma – suspensory ligament:

Also known as Astley Cooper’s ligament.

Fibrous band running through e breast.

Ataaches to e dermis & pectoral fascia.

Accompanied by lymphatic vessels. Function is to give breast its shape.

3. Fat.

Age – anatomical change:1. Before puberty: ducts empty into nipple,

but no lobules or alveoli.2. Puberty: ducts bud & form lobules.3. Pregnancy: true secretory alveoli.4. Menopause: glandular tissue involutes.

BLOOD SUPPLY

1. Arterial supply:a. Medial part: internal thoracic artery.b. Lateral part: lateral thoracic artery.c. Upper part: pectoral branch from thoracoacromial artery.d. Lateral cutaneous branch from posterior intercostals artery.

2. Venous drainage:a. Axillary vein.b. Internal thoracic vein.c. Lateral thoracic vein.

3. Lymphatic drainage: Lymph course – nipple → areolar → lobules → subareolar lymphatic plexus of Sappey to:

a. Most (75%): axillary LN via pectoral LN.b. E rest (25%): parasternal LN.c. Small amount: opposite to e breast, e abdominal wall.

Axillary lymph nodes:a. Functional:

i. Level 1: nodes below & lateral to pectoralis major.ii. Level 2: nodes behind pectoralis major.iii. Nodes above & medial to pectoralis major.

b. Anatomical:i. Pectoral or anterior LN: 3 or 5 LN that lie along e medial wall of axial around e

lateral thoracic vein & anterior border of pectoralis minor. They drain e anterior thoracic wall.

ii. Subscapular or posterior LN: 6 or 7 LN that lie along e posterior axillary fold & subscapular blood vessels.

iii. Humeral or lateral LN: 4 to 6 LN along e lateral wall of axilla, medial & posterior to e axillary vein which drains e posterior thoracic wall.

iv. Central LN: 3 to 4 LN located deep to e pectoalis minor near e base of axilla which receives all e 3 previous LN.

v. Apical LN: located at e apex of e axilla along e medial side of e axillary vein & e 1st part of axillary artery. It receives e central LN, then unite to form e seubclavian lymphatic trunk.

Lymphatic vessels in skin → axillary LN → inferior deep cervical LN → infraclavicular LN → parasternal LN.

Posterior intercostals lymphatic vessels communicate freely with vertebrae & spinal cord which can serve as e route for metastasize.

NERVE SUPPLY

1. Skin: anterior & lateral subcutaneous branch of 2nd through 6th intercostals nerve.2. Nipple & areolar: T4 spinal nerve.3. Upper & lateral parts: supraclavicular nerves from lower fibers of cervical plexus.4. Sympathetic: via intercostals nerve or vessels.

APPLIED 1. Development & growth: accessory nipples may develop along e milk line.2. Anomalies:

ANATOMY

a. Macromatia: unusual large breast which leads to back problem, ptosis, & ridicule. E treatment is mammoplasty.

b. Micromatia & amastia: small & absence of breast respectively.c. Congenital asymmetry.d. Polythelia: > 2 nipples around e milk line.e. Polymastia: > 2 breasts.f. Gynecomastia: large breast in male.

3. Clinical correlation:a. Orange – peel appearance: lymphatic vessels & LN blocked by tumors which lead to edema

of e skin.b. Dimpling: pulling of suspensory ligament by fibrous tissue which results in skin being

pulled inward.c. Retracted nipple: d/t cancer of e duct system.d. Adhesion of breast to thoracic wall: breast unable to move freely on pectoralis major.

THE BRACHIAL PLEXUS

PORTION DETAILS

ROOTS

Brachial plexus is a major nerve network that supplies e upper limb. It begins in e neck & extends into e axilla where most of its branches arise. It is formed by e union of e anterior rami of e last 4 cervical (C5 – C8) & e 1st thoracic (T1) that

constitutes as e roots of e brachial plexus. E roots usually pass through e gap b/w e anterior & e middle scalene muscles with subclavian

artery. E sympathetic fibers carried by each root r received from e gray rami of middle & inferior

cervical ganglia as e root pass b/w e scalene muscles. E roots have 2 branches:

1. Dorsal scapular nerve (C5): nerve to rhomboids.2. Long thoracic nerve (C5, C6, & C7).

TRUNKS

In e inferior part of e neck, e roots unite to form 3 trunks:1. Superior trunk:

E union of e C5 & C6 roots. E branches:

a. Nerve to subclavius (C5 & C6).b. Suprascapular nerve (C5 & C6).

2. Middle trunk: e continuation of e C7 root.3. Inferior trunk: e union of C8 & T1 roots.

DIVISIONS

Each trunk divides into anterior & posterior divisions as e plexus passes through e cervicoaxillary canal posterior to e clavicle.

E divisions r:1. Anterior divisions: supply e anterior (flexor) compartments of e upper limb. 2. Posterior divisions: supply e posterior (extensor) compartment of e upper limb.

CORD

E division of e trunks from 3 cords of e brachial plexus:1. Lateral cord:

E union of e anterior divisions of e superior & middle trunks. E branches:

a. Lateral pectoral nerve.b. Lateral root of median nerve.

2. Posterior cord: E union of e posterior divisions of all 3 trunks. E branches:

a. Upper subscapular nerve.b. Lower subscapular nerve.c. Thoracodorsal nerve.

3. Medial cord: E continuation of e anterior division of e inferior trunk. E branches:

a. Medial pectoral nerve.b. Medial root of median nerve.c. Musculocutaneous nerve of e arm.d. Musculocutaneous nerve of e forearm.

TERMINAL BRANCHES

1. E lateral cord:a. Musculocutaneous nerve:b. Median nerve:

2. E posterior cord:a. Radial nerve:b. Axillary nerve:

3. E medial cord:a. Ulnar nerve:b. Median nerve:

APPLIED ANATOMY

THE SKULL

BONES DETAILS

OVERVIEW

Functions:1. Protects e brain, meninges & e organs of special sense.2. Provides openings for passage of food & air.3. Houses teeth for mastication.

Consists of 22 bones joined together by sutures forming:1. Cranial Bones:

Consists of 8 flat & curved bones united by firbrous interlocking sutures:a. Frontal bone (1). d. Occipital bone (1).b. Parietal bone (2). e. Sphenoid bone (1).c. Temporal bone (2). f. Ethmoid bone (1).

They protect e brain and r grouped as e neurocranium which r in contact with e dura. E bones which r formed entirely in membrane that contribute to the cranial vault r

frontal & parietal bones. E endochondral bones which have membranous bony plates attached & contribute to

the skull vault r sphenoid, temporal, & occipital bones.2. Facial Bones:

Also known as viscerocranium which is made up of 14 bones: Membrane bone:

a. Zygomatic bone (2). d. Palatine bone (2).b. Nasal bone (2). e. Lacrimal bone (2).c. Vomer bone (1). f. Maxilla (2).

Membrane bone with 2o cartilage growth centre: mandible (1). Endochondral bone: inferior concha bone (2).

They provide protection, as extensions from e neurocranium, for some special sense organs such as eyes & olfactory organs.

They form e skeletal framework for primitive visceral functions such as feeding & respiration.

They r not in contact with e dura.

TEMPORAL BONE

Forms lateral wall & part of floor of cranial cavity.

4 parts:1. Tympanic part:

a. External auditory meatus.b. Styloid process for muscle

attachment.2. Mastoid part:

a. Mastoid process: mastoiditis from ear infection.

b. Mastoid notch: digastric muscle.

3. Petrous part: Forms part of cranial floor: separates

middle from posterior cranial fossa. Houses middle & inner ear cavities:

a. Receptors for hearing & sense of balance.

b. Internal auditory meatus is opening for CN VII (vestibulocochlear nerve).

4. Squamous part:a. Zygomatic process.b. Mandibular fossa & TMJ.

SPHENOID & ETHMOID

BONE

1. Ethmoid bone: Superior & middle nasal concha. Perpendicular plate of nasal septum.

2. Sphenoid bone: Greater & lesser wings. Body of sphenoid. Medial & lateral pterygoid processes.

PALATINE BONE

L-shaped bone. Posterior 1/3 of e hard palate. Part of e lateral nasal wall & e orbital floor.

ZYGOMATIC ARCH

Landmark structure of e lateral aspect of e skull. E relation:

1. Posterior to e zygomatic arch is e external auditory meatus & mastoid process.2. Anterior to e zygomatic arch is e orbital fossa.3. Superior to e zygomatic arch is e pterion. 4. Inferior to zgomatic arch is e vertical part of e mandible.

Notes:1. E pterion is formed b/w e frontal, parietal, temporal & greater wing of sphenoid. 2. Surface anatomy: 4 cm above e midpoint of e zygomatic arch & nearly same distance

behind e zygomatic process of frontal bone.

CLAVARIA

Sutures:1. Coronal suture: b/w frontal & parietal

bones.2. Sagittal suture: b/w parietal bones.3. Lambdoidal suture: b/w parietal & occipital

bones.

Landmarks:1. Bregma: mid point of coronal suture.2. Lambda: mid point of lambdoidal

suture.

CRANIAL FOSSA

3 basins that comprise e cranial floor or base:1. Anterior fossa holds e frontal lobe of e

brain.2. Middle fossa holds e temporal lobes of e

brain.3. Posterior fossa contains e cerebellum.

Swelling of e brain may force tissue through foramen magnum resulting in death.

MAXILLA Forms e upper jaw of e skull, surrounds most of e piriform aperture, & form e infraorbital margins medially.

Alveolar process: includes e tooth sockets (alveoli) & constitutes e supporting bone for e maxillary teeth.

Relations:1. Zygomatic bone laterally.2. An infraorbital foramen inferior to each orbit for passage of e infraorbital nerve & vessels.

E 2 maxillae r united at e intermaxillary suture in e median plane.

MANDIBLE

Only bone of e skull that can move. 3 parts: ramus, angle, & body of mandible. E jaw joint formed b/w mandibular fossa of

temporal bone & condyloid process. Internal features of e mandible:

1. Mandibular foramen: inferior alveolar neurovascular bundle.

2. Mylohyoid line: gives origin to mylohyoid muscle, which forms e floor of e mouth.

External features of e mandible 1. Coranoid process – attachment of

temporalis. 2. Ramus of mandible – attachment of

masseter. 3. Angle of mandible – attachment of

masseter. 4. Body of mandible – attachment of

buccinator.5. Mental foramen: mental nerve &

vessels. Functions:

1. Holds e lower teeth.2. Attachment of muscles of mastication.

INFANT SKULL

Infants have frontal squama divided by metopic suture that fuse by age 6 yrs. Glabella (Latin for smooth and hairless) b/w superciliary arches. Nasion: root of the nose. Fontanelles: membrane link bones at birth.

1. Anterior fontanelle at Bregma.2. Posterior fontanelle at Lambda.3. Lateral fontanelle at Pterion.

FORAMINA & APERTURES OF THE CRANIAL FOSSAE

FORAMINA CONTENTS

ANTERIOR CRANIAL FOSSAFORAMEN CECUM Nasal emissary vein (15% of population).

CRIBRIFORM FORAMINA (in cribriform plate) Axons of olfactory cells in olfactory epithelium that form olfactory nerve.

ANTERIOR & POSTERIOR ETHMOIDAL FORAMINA Vessels & nerve with same names.

MIDDLE CRANIAL FOSSA

OPTIC CANALS 1. Optic nerve (CN II).2. Ophthalmic artery.

SUPERIOR ORBITAL FISSURES

1. Ophthalmic veins.2. Ophthalmic nerve (CN V1).

3. CN III, IV, & VI.4. Sympathetic fibers.

FORAMEN ROTUNDUM Maxillary nerve (CN V2).

FORAMEN OVALE 1. Mandibular nerve (CN V3).2. Accessory meningeal artery.

FORAMEN SPINOSUM 1. Middle meningeal artery & vein.2. Meningeal branch of CN V3.

FORAMEN LACERUM Internal carotid artery & its accompanying sympathetic & venous plexus.

GROOVE OR HIATUS OF GREATER PETROSAL NERVE

1. Greater petrosal nerve.2. Petrosal branch of middle meningeal artery.

POSTERIOR CRANIAL FOSSA

FORAMEN MAGNUM

1. Medulla & meninges.2. Vertebral artery.

3. CN XI.4. Dural vein.

5. Anterior & posterior spinal artery.

JUGULAR FORAMEN

1. CN IX, X, & XI.2. Superior bulb of internal jugular vein.3. Inferior petrosal & sigmoid sinuses.

4. Meningeal branches of ascending pharyngeal & occipital arteries.

HYPOGLOSSAL CANAL Hypoglossal nerve (CN XII).

CONDYLAR CANAL Emissary vein that passes from sigmoid sinus to vertebral veins in e neck.

MASTOID FORAMEN Mastoid emissary vein from sigmoid sinus & meningeal branch of occipital artery.

THE SCALP

PORTION DETAILS

OVERVIEW

Consists of skin & subcutaneous tissue which cover e neurocranium from e superior nuchal line on e occipital bone to e supraorbital margins of e frontal bone.

Laterally, it extends over e temporal fascia to e zygomatic arches. It continues deeply with e laminae of e cranium & meninges.

LAYERS OF SCALP

SKIN Thin, except in e occipital region which contains many sweat, sebaceous gland, & hair follicles. It has an abundant arterial supply & good venous & lymphatic drainage.

DENSE CT A thick, dense, & richly vascularized subcutaneous layer that is well supplied with cutaneous nerve.

APONEUROSIS

A broad & strong tendinous sheet that covers e calvaria. Serves as e attachment for muscle bellies converging from e forehead & occiput (e

occipitofrontalis muscle) & from e temporal bones on each side (e temporoparietalis & superior auricular muscles).

Constitutes e musculoaponeurotic epicranius which is innervated by e facial nerve. E occipitofrontalis muscle:

From e highest nuchal line to e eyebrow. E occipital & frontalis muscles r connected by epicranial aponeurosis (Galea Aponeurotica). E muscles:

1. Occipitalis muscle: Attached to e lateral 3rd of highest nuchal line of occipital bone & mastoid part of

temporal bone & ends in aponeurosis. Nerve supply: posterior auricular branch of Cranial nerve 7. Action: draws e scalp below.

2. Frontalis muscle: Subcutaneous fascia of eyebrow to aponeurosis. Medial & lateral part blen with nearby muscle with no bony attachment. Berve supply: temporal branch of Cranial nerve 7. Actions:

a. From above: it raises e eyebrows & skin over e root of nose. E eyebrom elevation is accompanied by glancing upward in e expression of surprise, horror, & fright.

b. From below: it draws e scalp forward, throwing e forehead into transverse wrinkles.

Both muscles: acting alternately to move e entire scalp forward & below.

LOOSE CT A sponge-like layer including potential space that may distend with fluid as a result of injury or

infection. It allows free movement of e scalp proper over e underlying calvaria.

PERICARNIUM A dense layer of connective tissue that form e external periostem of e neurocarnium. It is firmly attached but can be striped fairly easily from e crania except where e pericranium is

continuous with e fibrous tissue in e cranial sutures.

BLOOD & NERVE SUPPLY Nerve supply:

1. Supratrochlear nerve.2. Supraorbital nerve.3. Zygomatic-temporal nerve → Maxillary nerve.4. Auriclotemporal nerve.5. Lesser & greater occipital nerves → Cervical

plexus. Lymphatic drainage:

1. Anterior: submandibular lymph nodes.2. Lateral (above e ear): superficial parotid nodes.3. Lateral (behind e ear): mastoid nodes.4. Posterior: occipital nodes.

Arterial blood supply:1. Supratrochlear artery.2. Supraorbital artery.3. Superficial temporal artery.4. Posterior auricular artery.5. Occipital artery.

Venous drainage:1. Supraorbital & supratrochlear veins drain into

facial vein.2. Superficial temporal vein drains into

retromandibular vein.3. Posterior auricular vein drains into external jugular

vein.4. Occipital vein drains into suboccipital venous

plexus.

APPLIED ANATOMY1. 1st 3 layers act like a single layer, i.e. when torn off in accidents or turned down surgically, they remain firmly

connected to each other.2. Sub-aponeurotic tissue: important surgically because it is loose, lax, & easily torn.3. Aponeurosis:

Slides freely on e pericranium. If injured leads to teraing of e underlying loose layer & e emissary veins which pass through it. Bleeding deep to aponeurosis leads to wide area of blood spread when raising e scalp from e skull.

4. Extracranial infection via venous drainage (emissary veins) spread into intracranial infection because e veins connected to e diploic veins of e skull & to e intracranial venous sinuses r valveless.

5. Scalp infection is evident by palpable e neck LN.6. Wrinking of e forehead & eyebrow elevation by e frontalis muscle. (palsy of UMNL or LMNL can be tested by 7th

Cranial nerve).

Ophthalmic

MUSCLES OF FACIAL EXPRESSION

MUSCLES ORIGIN INSERTION NERVE SUPPLY ACTIONS

MUSCLES OF E EYELIDS & EYEBROWLEVATOR

PALPEBRAL SUPERIORIS

- - 3rd Cranial Nerve. Raises e upper lid.

ORBICULARIS OCULI

1. Medial orbital margin.

2. Medial palpebral ligament.

3. Lacrimal bone.

1. Skin around margin of orbit.

2. Superior & inferior tarsal plate.

7th Cranial nerve: temporal &

zygomatic branches.

1. Palpebral part: closes e lids as in blinking & sleep.

2. Orbital part: closes lids but with greater force as in

winking.3. Lacrimal part:

draws e eyelids & lacrimal canal medially,

compressing them against e globe of eye to

receive tears.

CORRUGATOR SUPERFICILLI

Medial end of superficially arch.

Skin superior to middle of

supraorbital margin & supercilliary arch.

7th Cranial nerve: temporal branch.

Draws eyebrow down & medially, producing vertical wrinkles of

forehead (frowning).

MUSCLES OF E NOSE

PROCERUS

Fascia aponeurosis covering nasal bone

& lateral nasal cartilage.

Skin of inferior forehead b/w

eyebrows. 7th Cranial nerve: buccal branch.

Produces transverse wrinkles over e bridge of e

nose.

NASALIS

1.Transverse part: depresses cartilaginous portion of nose & draws

alae toward septum.2.Alar part: dilates nostrils

(during breathing, it resists tendency of nares

to close from ATM).3.Noticeable in anger or

labored breathing.

DEPRESSOR SEPTI - -

1.Draws e alae of e nose downward.

2.Constricts nares.

MUSCLES OF E FOREHEAD

OCCIPITO-FRONTALIS

1. Frontal belly: epicranial

aponeurosis.

Skin & subcutaneous tissue of eyebrows &

forehead.

Temporal branch of 7th Cranial nerve.

1.Contracting together, both draw e scalp up &

back, thus raising e eyebrows (surprise).

2.Assist with wrinkling of e forehead.

3.Working alone: e frontal belly raises e eyebrow

on e same side.

4. Occipital bely: lateral 2/3

of superior nuchal line.

Epicranial aponeurosis.

Posterior auricular branch of 7th Cranial

nerve.

MUSCLES OF E CHEECK & MOUTH

BUCCINATOR

1. Mandible.2. Alveolar process

of maxilla & mandible.

3. Pterygomsndibular raphe.

1. Angle of mouth.2. Orbicularis oris.

Buccal branch of 7th

Cranial nerve.1. Compresses cheek

against e teeth.2. Expels air when cheeks

r distended (in blowing).

3. Acts in mastication to control passage of food.

ORBICULARIS ORIS

1. Medial maxilla & mandible.

2. Deep surface of perioral skin.

3. Angle of mouth.

Mucous membrane of lips.

1. Closes & protrudes lips.2. Holds lips tight against

teeth.3. Shapes lips for

whistling, kissing, sucking, & drinking.

4. Alters e shape of lips for articulation.

LEVATOR ANGULI ORIS

Infraorbital maxilla (canine fossa).

Angle of mouth. 1. Raises e angle of mouth & by so doing displays

teeth ij smiling.2. Contributes to

nasolabial furrow (from

side of nose to corner of upper lip).

3. Deepens in sadness & age.

LEVATOR LABII SUPERIOR

ALAQUE NASI

Frontal process of maxilla. Major alar cartilage. 1. Dilates nostrils.

2. Elevates upper lip.

ZYGOMATICUS MAJOR

Lateral aspect of zygomatic bone. Angle of mouth.

Draws e angle of mouth lateral & upward as in

laughing.

MENTALIS Body of mandible. Skin of chin. Mandibular branch of 7th Cranial nerve.

1. Wrinkles skin over chin.2. Protrudes lower lip as in

sucking & pouting.

DEPRESSOR LABII

INFERIORIS

Platysma & anterolateral body

of mandible.Skin of lower lip. Mandibular branch of

7th Cranial nerve.

Draws e lower lip down & laterally, producing an

expression of melancholy or irony.

MUSCLES OF MASTICATION

MASSETER Zygomatic arch. Lateral surface ramus of mandible.

Mandibular division of trigeminal nerve.

Elevates mandible to occlude teeth.

TEMPORALIS Floor of temporal fossa.

Coronoid process of mandible.

1. Anterior & superior fibers elevate

mandible.2. Posterior fibers

retract mandible.

LATERAL PTERYGOID

1. Greater wing of sphenoid.

2. Lateral pterygoid plate.

Neck of mandible & articular disc.

Pull e neck of mandible forward.

MEDIAL PTERYGOID

1. Tuberosity of maxilla.

2. Lateral pterygoid plate.

Medial surface of angle of mandible. Elevates mandible.

CUTANEOUS & SUBCUTANEOUS MUSCLES

PLATYSMA

Subcutaneous tissue of

infraclavicular & supraclavicular

regions.

1. Base of mandible.2. Skin of cheek &

lower lip.3. Angle of mouth.4. Orbicularis oris.

Branches of e parotid plexus.

1. Depresses e lower lip & e buccal angle of e mouth to give an

expression of grief or sadness.

2. Draws e lower lip backward, producing an

expression of horror.3. Pulls up e skin of neck

of e neck from e clavicle evoking e

expression of egad.

STERNOCLEIDO-MASTOID

1. Lateral surface of mastoid process of

temporal bone.2. Lateral half of

superior nuchal line.

1. Sterna head: anterior surface of manubrium.

2. Clavicular head: superior surface of medial 3rd of

calvicle.

1. Motor: spinal accessory nerve

(CN XI).2. Pain &

proprioception: C2 & C3 nerves.

1. Unilateral contraction: tilt head to e same side.

2. Bilateral contraction:a. Extends neck at atlanto-

occipital joint.b. Flexes cervical vertebra

so that chin touches manubrium.

APPLIED ANATOMY Differentiation b/w UMNL & LMNL of facial nerve:

1. Ask to smile: both types will be showing e obvious asymmetry of e face.

2. Ask to close e eyes:a. LMNL: cannot be closed & there will be upward

eye deviation.

b. UMNL: can be closed.3. Ask to elevate eyebrows:

a. LMNL: cannot raise & lack of wrinkling of e forehead.

b. UMNL: can elevate.

THE PAROTID GLAND

PORTION DETAILS

OVERVIEW A paired gland which is e largest salivary gland exocrine in nature. Secrete mostly serous saliva. E shape is irregular & pyramidal. Location (parotid bed):

1. Anteroinferior to external acoustic meatus.

2. Wedged b/w ramus of mandible & mastoid process.

PARTS

1. Apex: Overlies posterior belly of digastrics & part of carotid triangle. Cervical branch of fascial nerve & retromandibular vein emerge through it. Located deep against e styloid process & infratemporal fossa.

2. Base: faces laterally b/w anterior border of stenocleidomastoid muscle & ramus of mandible.3. E subcutaneous lateral surface of parotid gland is almost flat.

CAPSULE

E parotid sheath: A though & dense fibrous capsule derived from e investing layer of deep cervical fascia. It encloses e parotid gland to form a capsule. Its lower end splits into 2 layers:

1. Superficial layer: a thick layer attached to zygomatic arch whilst anteriorly merges with e tissue of e cheek.

2. Deep layer: A thin layer attached to e tympanic part of temporal bone. A portion is thickened b/w styloid process & angle of mandible to form

stylomandibular ligament.

PROCESSES

1. Superior: glenoid process – extends laterally b/w anterior border of SCM & ramus of mandible.2. Anterior: facial process – superficial to masseter muscle.3. Accessory process – a small part of fascial process may separate it from e main gland.4. Inferior: pterygoid – deep part extends inferiorly b/w medial pterygoid & ramus of mandible.

RELATIONS

1. Superior:a. External acoustic meatus.b. Posterior surface of TMJ.c. Auriculotemporal nerve & vessels.d. Superficial temporal vessels.

2. Superficial:a. Great auricular nerve (C2 & C3).b. Superficial fascia & parotid fascia.c. Deep parotid LN (embedded).

3. Antero-medial:a. Masseter muscle.b. Lateral surface of TMJ.c. Posterior ramus of mandible.d. Medial pterygoid muscle.e. Emerging branch of facial nerve.

4. Posteromedial:a. Mastoid process, SCM, & posterior belly

of digastrics.b. Facial nerve.c. Styloid process & its attached muscles:

Stylohyoid muscle. Styloglossus muscle. Stylopharyngeus muscle.

d. Carotid sheath & its contents: E carotid artery. Internal jugular vein. Glossopharyngeal, accessory, &

vagus nerves.e. External carotid artery.

BORDERS

1. Anterior: it is indented d/t:

a. Masseter muscle.b. Mandible.c. Medial pterygoid muscle.

Structures emerge through it:a. Parotid duct.b. Most of terminal branch of facial nerve,c. Transverse facial vessels.

2. Posterior: overlaps SCM.3. Medial: related to e lateral wall of pharynx.

STRUCTURE EMBEDDED IN E GLAND

1. Nerve: facial nerve.2. Vein: retromandibular vein formed by superficial temporary & maxillary veins.3. Artery:

a. External carotis artery.b. Maxillary artery.c. Superficial temporal vessels.d. Posterior auricular artery.

4. Parotid lymph nodes.

BLOOD & NERVE SUPPLY

1. Arterial supply: superficial temporal & maxillary arteries, e branches of external carotid artery.2. Venous drainage: retromandibular veins.3. Lymphatic drainage:

a. Parotid lymph nodes.b. Deep cervical lymph nodes.

4. Nerve supply:a. Secremotor:

Secretory supply to parotid gland. 2 parts:

i. Preganglionic fibers: inferior salivary nucleus in brain → CN IX comes out from posterior cranial fossa in jugular foramen → gives branch, i.e. tympanic branch & form tympanic plexus in e middle ear → lesser petrosal nerve (comes out from middle cranial fossa in foramen ovale) → synapse in otic ganglion.

ii. Postganglionic fibers: auriculotemporal nerve → parotid gland. b. Vasomotor: derived from cervical ganglia through external carotid nerve plexus (plexus

around external carotid artery).c. Sensory:

i. To parotid gland: auriculotemporal nerve.ii. To parotid fascia: greater auricular nerve.

PAROTID DUCT

E duct of parotid gland which is 5 cm long. Course: passes horizontally from e anterior edge of e gland over e masseter one fingerbreadth

below e zygomatic arch → turns medially → pierces e buccinators → opens obliquely into vestibule of e mouth (opposite to e maxillary 2nd molar tooth).

E duct is palpable over anterior edge of e masseter when it contracts. Relations:

1. Superior:a. Accessory part of parotid gland.b. Buccal branch of facial nerve (upper).c. Transverse facial vessels.

2. Inferior: buccal branch of facial nerve (lower). Accessory duct opens into e upper border of e parotid duct.

APPLIED ANATOMY

1. Extension of e parotid gland: E gland is extend upward b/w external acoustic meatus & TMJ. If there is parotiditis, any TMJ movement will cause pain.

2. Paratidectomy: In e surgery, e facial nerve plexus & its branches r in jeopardy because they r embedded in e

gland. Thus, safety steps should be taken to avoid e nerves from damage:

a. Identification.b. Isolation.c. Preservation of facial nerve.

3. Tumor: Any tumor in e gland may compress facial nerve & leads to facial palsy. Results in referred pain in TMJ.

FASCIAE OF THE NECK

PORTION DETAILS

SUPERFICIAL FASCIA1. E subcutaneous tissue of e neck:

A layer of fatty connective tissue that lies b/w e dermis of e skin & e investing layer of deep cervical fascia. It is thinner than e other regions. It contains cutaneous nerves, blood, & lymphatic vessels, superficial LN, & fat.

2. Platysma: A broad, thin sheet of muscle in e subcutaneous tissue of e neck in e anterolateral position. Functions:

a. Acting from superior attachment: tenses e skin to produce vertical skin ridges & to release pressure on e superficial veins.

b. Acting from inferior attachment: Helps depress e mandible. Draws e corner of e mouth inferiorly as in a grimace. Serves to convey tension or stress.

DEEP CERVICAL FASCIAE

FUNCTIONS

1. Support e tissue & organs.2. Allow e structures in e neck to move & pass over one another easily.3. Act as a barrier to prevent spreading infection & abscess.4. Determine e direction of spreading infection.

INVESTING LAYER

E most superficial deep facial layer surrounding e entire neck deep to skin & subcutaneous tissue.

It splits into superficial & deep layers at e 4 corners of e neck to enclose e trapezius & SCM. It forms e roof of e posterior triangle by investing SCM. Anteriorly, it covers e anterior triangle & fuses with e opposite fascia in e midline. Superiorly, it attaches to e:

1. Superior nuchal line of e occipital bone.2. Mastoid process of e temporal bone.3. Zygomatic arches.4. Hyoid bone.5. Spinous process of cervical vertebra.

Inferiorly, it attaches to e: 1. Manubrium.2. Clavicle.3. Acromion & spine of e scapula.

Due to e mandible, it splits to: 1. Enclose submandibular gland inferiorly.2. Form fibrous capsule of parotid gland posteriorly.

PRETRACHEAL LAYER

It lies deep to infrahyoid strap muscles limited superiorly at hyoid & oblique line to thyroid cartilage more laterally.

It splits to enclose e thyroid gland & adheres at isthmus level 2, 3, & 4 rings of trachea. Behind e thyroid, it condenses & adheres to cricoids cartilage & 1st ring of trachea (Berry’s

ligament). Laterally, it fiuses with e front of e carotid sheath on e deep surface of SCM. Inferiorly, it passes behind e brachiocephalic veins to blend with e adventitia of e aortic arch &

fibrous pericardium.

It surround e pharynx, esophagus, larynx, & trachea.

PREVERTEBRAL LAYER

It originates from e cervical spinous process & e nuchal ligament. It then extends to either side to cover e deep muscles of e neck along e cervical spine &

attaches to it transverse process. Anteriorly, it covers e prevertbral muscles, e muscles that form e floor of posterior triangle, &

all e cervical nerev roots. E LN & accessory nerve lie superficial to it. It prolongs over e subclavian artery & a brachial plexus below e clavicle as axillary sheath. It is pierced by 4 cutaneous branches of cervical plexus.

CAROTID SHEATH

It is attached to e base of e skull at margins of carotid canal & jugular fossa. It continues downwards along e vessels to blend with adventitia of aortic arch. Contents:

1. Common carotid artery.2. Internal carotid artery.3. Internal jugular veins, & e vagus nerve. E artery is depp & medial to internal jugular vein & e vagus nerve is posterior to e carotid

artery. It is anterior to e cervical sympathetic trunk which lies on e longus colli & longus capitis

muscles in front of cervical vertebra.

ALAR FASCIA A portion of e deep layer, extending inferiorly from e skull base & attaching to e transverse

processes of e vertebrae as it descends to e level of trachea bifurcation at T2. It separates e retropharyngeal space from prevertebral space.

SPACES OF THE NECK

PORTIONS DETAILS

FACIAL PLANE & SPACE

A facial plane represents a condensation of connective tissue lying b/w adjacent structures. Facial spaces r e potential spaces b/w facial plane. When an abscess forms in a space, spread to other spaces occurs along planes of least

resistance because of e inter r/ship & continuity of deep cervical fascia & potential spaces.

GROUP OF SAPCES

1. Spaces involving e entire length of e neck:a. Retropharyngeal space.b. Prevertebral space.c. Visceral vascular space (within e carotid sheath).d. Danger space.

2. Spaces above e hyoid bone:a. Submandibular space.b. Sublingual space.c. Submaxillary space.d. Parapharyngeal or lateral pharyngeal space.e. Masticator space (masseter, pterygoid, & temporalis muscles).

3. Space below e hyoid bone (anterior only).a. Anterior visceral (pretracheal) space.

IMPORTANT SPACES

RETRO-PHARYNGEAL

SPACE

It is a potential space that exists b/w e posterior aspect of e visceral layer & e alar division of e deep layer.

It extends from e base of e skull to e level of e 1st or 2nd thoracic vertebrae. It contains 2 lateral chains of LN separated by a midline raphe.

DANGER SPACE It lies b/w e alar & prevertebral layers of e deep cervical fascia. It extends from e base of e skull to e posterior mediastinum at e level of diaphragm. It is limited laterally by its fusion with e prevertbral layer & e vertebral transverse process.

PREVERTEBRAL SPACE

It lies b/w e vertebral bodies & e prevertebral layer of e deep cervical fascia. It extends from e base of e skull to e level of coccyx.

PARAPHARYNGEAL SPACE

This space can be compared to an inverted cone with its base lying superiorly at e base of e skull & its apex inferiorly at e hyoid bone.

It is divided into a prestyloid & poststyloid component by tensor-vascular-styloid fascia connecting tensor palatine muscle with styloid process.

Its medial & lateral borders r, respectively, e lateral pharyngeal wall & e superficial layer of e deep cervical fascia.

It overlies:1. Mandible.2. Parotid gland.3. Internal pterygoid.

SUBMANDIBULAR SPACE

It is divided by e mylohyoid muscle into e sublingual space above & e submaxillary space below.

These 2 spaces communicate freely around e posterior edge of mylohyoid muscle. E entire space is bounded by e mandible anteriorly & laterally. E hyoid bone limits its inferior aspect & e intrinsic muscles of e base of e tongue form its

posterior border. E sublingual space contains e sublingual gland, e hypoglossal nerve, & Wharton’s duct. E submandibular space contains e submandibular gland.

MASTICATOR SPACE

It is formed by e splitting of e superficial layer of e cervical fascia to enclose:1. E ramus of e mandible.

2. E masseter.3. E medial pterygoid.4. E lower portion of e temporal muscle.

ANTERIOR VISCERAL SPACE

It lies in e anterior aspect of e neck & enclosed by e visceral layer. It completely surrounds e trachea, esophagus, & thyroid gland. It extends from e thyroid cartilage to e level of e 4th thoracic vertebrae in e superior

mediastinum.

RELATIONSHIP B/W FASCIAE & SPACES OF THE NECK

SPACE ASSOCIATED FASCIA EXTENT CONTENTS

Superficial space B/w SCF & superficial layer of DCF

Skull base to mediastinum

1. Platysma muscle2. Lymph nodes

Carotid space All 3 layers of DCFSkull base to

mediastinum (aortic arch)

1. Carotid artery2. Jugular vein

3. Lymph nodes4. Nerve

Visceral space Covered by pretracheal fascia Hyoid bone to mediastinum

1. Thyroid & parathyroid2. Larynx & pharynx

3. Trachea4. Esophagus

5. Recurrent laryngeal nerve

6. Lymph nodes

Retropharyngeal space B/w e visceral layer & e alar layer

Skull base to mediastinum (T3)

1. Fat2. Lymph nodes in

suprahyoid compartment.

Danger space B/w alar & prevertebral layersSkull base to mediastinum (diaphragm)

Fat

Prevertabral space B/w e vertebral bodies & e prevertebral layer Skull base to coccyx

1. Prevertebral2. Paraspinal & scalene

muscle3. Phrenic nerve

4. Vertebral artery & veins5. Vertebrae.

THE TRIANGLES OF THE NECK

TRIANGLES BOUNDARIES CONTENTS

POSTERIOR TRIANGLES

Occipital triangle1. Base: middle 1/3 of e clavicle.2. Anterior: posterior edge of SCM.3. Posterior: anterior edge of trapezius.4. Apex: superior nuchal line on e

occipital bone.5. Roof: e investing layer of deep cervical

fascia.6. Floor: prevertebral fascia.

1. Nerves:a. 4 cutaneous branches of cervical plexus.b. Accessory nerve.c. Supraclavicular part of brachial plexus.d. Ventral primary rami of C5 to T1.

2. Arteries:a. 3rd part of subclavian artery.b. Transverse cervical artery.c. Suprascapular artery.

3. External jugular vein.4. Omohyoid muscle.5. Occipital & supraclavicular (inferior deep

cervical) lymph nodes.

Subclavian triangle (supraclavicular

fossa)

ANTERIOR TRIANGLES

Submental triangle

1. Inferior: body of hyoid.2. Lateral: Rt. & Lt. anterior bellies of e

digastrics muscles (meet in median fibrous raphe).

3. Apex: mandibular symphysis.4. Floor: 2 mylohyoid muscles.5. Base: hyoid.

1. Anterior jugular vein.2. Submental lymph nodes.

Submandibular triangle

1. Superior: inferior border of mandible.2. Lateral: anterior & posterior bellies of e

digastrics muscles.3. Floor:

a. Mylohyoid muscle.b. Hyoglossus muscle.c. Middle constrictor muscle of e

pharynx.

1. Submandibular gland.2. Submandibular lymph nodes.3. Nerves:

a. Hypoglossal (CN XII).b. Nerve to e mylohyoid muscle (CN V3).

4. Vessels:a. Facial artery & vein.b. Submental artery.c. Mylohyoid vessels.

Carotid triangle

1. Boundaries:a. Superior belly of e omohyoid.b. Posterior belly of e digastric.c. Anterior border of e SCM.

2. Floor:a. Thyrohyoid muscle.b. Hyoglossus muscle.c. Middle & inferior constrictor of

pharynx.

1. Arteries:a. Bifurcation of common carotid artery.b. Branches of external carotid artery

except posterior auricular.2. Veins:

a. Facial vein.b. Superior thyroid vein.

3. Nerves:a. Hypoglossal nerve.b. Internal & external laryngeal nerves.

4. Posterior root of ansa cervicalis.5. Deep cervical lymph nodes.6. Carotid sinus:

A slight dilation of e proximal part of e internal carotid artery.

Innervated by glossopharyngeal & vagus nerves.

A baroreceptor that reacts to changes in arterial blood pressure.

7. Carotid body: A small, reddish brown ovoid mass of

tissue lying deep to e bifurcation of e common carotid artery in e close relation to e carotid sinus.

Innervated by carotid sinus (CN IX & CN X).

A chemoreceptor that monitor e level f oxygen in e blood.

Muscular triangle

1. Boundaries:a. SCM.b. Superior belly of omohyoid.c. Midline from hyoid bone to jugular

notch.2. Floor:

a. Sternohyoid muscle.b. Sternothyrois muscle.c. Beneath e floor lie larynx, trachea, &

oesophagus.

1. Parts of larynx.2. Trachea.3. Pharynx.4. Oesophagus.5. Thyroid & parathyroid gland.6. Vessels, nerves, & LN of e above organs.

APPLIED ANATOMY Lines of natural creases: Langer’s line.

Water-shed at e middle of neck: site prone for ischemic necrosis.

THE SUBMANDIBULAR REGION

PORTION DETAILS

SUPRAHYOID MUSCLES

MUSCLES ORIGIN INSERTION NERVE SUPPLY ACTION

DIGASTRIC

1. Posterior belly: mastoid notch of temporal bone.

2. Anterior belly: inner side of mandible.

Hyoid bone via intermediate tendon.

1. Posterior belly: facial nerve.

2. Anterior belly: trigeminal nerve.

1. Elevates hyoid bone.2. Depresses mandible.

STYLOHYOID Styloid process of temporal bone.

Hyoid bone.

Facial nerve. Elevates hyoid bone.

MYLOHYOID Mylohyoid line of mandible. Trigeminal nerve.

1. Elevates hyoid bone.2. Raises floor of

mouth during swallowing.

GENIOHYOID Inner side of mandibleC1 via branch hitch

hiking with hypoglossal nerve.

1. Elevates hyoid bone.2. Draws hyoid forwad.

STRUCTURES RELATED TO MYLOHYOID & HYOGLOSSUS MUSCLES1. Structures deep to mylohyoid but superficial to hyoglossus muscle:

a. E lingual nerve.b. E deep process of e submandibular gland. c. E submandibular duct. Pass deep to e posterior border of e mylohyoid.d. E hypoglossal nerve.

2. Structures deep to hyoglossus muscle: e lingual artery pass deep to e posterior border of e hyoglossus.

SUBMANDIBULAR GLAND

OVERVIEW

Referred to submaxillary gland. It is a U-shaped or C-shaped which is e size of a walnut (thumb) weighs ½ of e weight of parotid

gland (8 gm). It is a mixed serous & mucus gland. Its location:

Lies in e submandibular triangle, partly undercover of body of mandible. Beneath e floor of e mouth. Inferior to mylohyoid muscle. Superior to digastrics muscle.

CAPSULE 1. Inner fibrous capsule.2. External capsule: derived from e investing layer of deep cervical fascia.

LOBES

E gland forms a “C” around e anterior margin of e mylohyoid muscle which divides e gland into:1. Superficial lobe:

A larger lobe which lies superficial to mylohyoid muscle. Located in digastrics or submandibular triangle. It is separated from parotid gland by stylomandibular ligament.

2. Deep lobe: Located deep to mylohyoid muscle. Located superficial to hyoglossus muscle.

RELATION

Superficial lobe:1. Anterior: anterior belly of digastrics.2. Posterior: posterior belly of digastrics,

stylohyoid & stylomandibular ligaments, & parotid gland.

3. Medial or deep: mylohyoid (behind it r hyoglossus muscle, lingual nerve, & hypoglossal nerve).

4. Lateral or superficial: skin, platysma, investing layer of DCF, marginal mandibular branch of CN VII, & cervical branch of facila nerve (CN VII).

Deep lobe:1. Lateral: mylohyoid muscle.2. Medial: hyoglossus & styloglossus.3. Superior: lingual nerve & submandibular

ganglion.4. Inferior: hypoglossal nerve (CN XII).5. Anterior: sublingual gland.6. Posterior: posterior belly of digastrics,

stylohyoid & stylomandibular ligaments, & parotid gland.

BLOOD SUPPLY

1. Artery:a. Facial artery.b. Lingual artery.

2. Vein:a. Facial vein.b. Lingual vein.

3. Lympathic drainage:a. Deep cervical lymph nodes.b. Jugular chains of nodes.

NERVE SUPPLY

1. Parasympathetic: Superior salivatory nucleus → facial nerve → chorda tympani → lingual nerve → SM ganglion

→ postganglionic fiber → SM gland.2. Sympathetic:

Superior cervical ganglion via lingual artery → facial plexus → SM gland.

SM DUCT Also know as Wharton’s duct. E length is 5 cm long.

B/w mylohyoid & hyoglossus muscles.

It emerges from deep lobe, forward b/w mylohyoid (lateral) & hyoglossus (medial). It courses b/w SM gland & genioglossus muscle. It opens into 1-3 orifices on either side of lingual frenulum. It is crossed twice by lingual nerve (wrapped by lingual nerve):

1. Lateral aspect near its origin.2. Medial aspect near it termination.

APPLIED ANATOMY

1. Common site of calculus formation: 80% - 90% of salivary gland stones occur in e SM gland & of those, 85% occur in Wharton’s

duct. E stone in e duct can be felt bimanually. Presence of tense body swelling below body of mandible, greatest before & during meal, &

reduced in size or absent b/w meals. Complication of operation:

a. Neuroprexia or paralysis of mandibular branch of facial nerve.b. Hemorrhage.c. Damage to lingual nerve: leads to numbness or paraesthesia of e ipsilateral tongue & loss

of sensation.d. Damage of hypoglossal nerve: ipsilateral tongue paralysis.

2. Presence of small LN in e substance of e gland makes removal of e gland an imperative part of block dissection of e neck.

3. Effects of aging: Acinar cells do generate with age. E SM gland is > sensitive to metabolic & physiologic changes.

4. Ludwig’s angina: Most often originate in an infected tooth. E tissue edema produced by Ludwig’s angina cannot spread downward & instead pushes e

base of e tongue backward, producing airway obstruction.

SUBLINGUAL GLAND

OVERVIEW

E smallest (4 gm) & deepest (situated) salivary gland which is almond in shaped. Located:

1. Below e mucus membrane of e floor of e mouth.2. Adjacent to (behind) mandible.3. Deep to e mylohyoid below.

It has no true capsule.

RELATION

1. Anterior: opposite lobe.2. Posterior: deep lobe of SM gland.3. Medial: genioglossus, lingual, & SM duct (b/w mylohyoid & hyoglossus).4. Lateral: sublingual fossa on medial surface of mandible.5. Superior: elevates mucosa of floor of mouth & forms sublingual fold.6. Inferior: mylohyoid.

DUCTS

1. Small: Ducts of Rivinus. Numerous: 10 – 12. Exist e superior aspect of e gland & open into:

a. Floor of mouth along sublingual fold.b. SM duct.

Too small for sialogram. 2. Big:

Bartholin’s Duct. A union of small ducts. Typically empties into Wharton’s duct.

BLOOD SUPPLY

1. Artery:a. Sublingual branch of lingual artery.b. Submental branch of facial artery.

2. Vein: reflects e arterial supplies.3. Lymphatic drainage:

a. Submandibular nodes.b. Deep cervical lymph nodes.c. Jugular chains of nodes.

NERVE SUPPLY

1. Sympathetic: cervical chain ganglia via facial artery.2. Parasympathetic: submandibular ganglion.

TEMPORAL & INFRATEMPORAL FOSSA

TEMPORAL FOSSA CONTENT INFRATEMPORAL FOSSA Refers to e region superior to e

zygomatic arch. Communicates with infratemporal fossa

via e interval b/w zygomatic arch & e cranial bone.

OVERVIEW

Refers to an irregularly shaped space deep & inferior to e zygomatic arch, deep to e ramus of e mandible, & posterior to e maxilla.

1. Posterior & superior: superior temporal line.

2. Anterior:a. Frontal bone.b. Frontal process of zygomatic bone.

3. Lateral: zygomatic arch.4. Inferior: infratemporal crest.5. Roof: temporal fascia.6. Floor: pterion:

H-shaped structure. Overlies e anterior branches of e

middle meningeal vessels. Formed by 4 bones: frontal, parietal,

temporal, & greater wing of sphenoid.

BOUNDARIES

1. Lateral: e ramus of e mandible.2. Medial: e lateral pterygoid plate.3. Anterior: e posterior aspect of e maxilla.4. Posterior:

a. E tympanic plate.b. E mastoid & styloid processes of e

temporal bone.c. Carotid sheath.

5. Roof: e inferior surface of e greater wing of e sphenoid (where foramen ovale & spinosum opens)

6. Inferior: where e medial pterygoid muscle attaches to e mandible near its angle.

7. Floor: there is no anatomical floor.

1. Temporalis muscle: Covered with temporal fascia. Origin: e temporal fossa. Insertion: coronoid process &

anterior border of ramus of mandible as far as e 3rd molar tooth.

2. 2 structures superficial to e muscle:a. Superficial temporal vessels:

i. Artery: Branch of external carotid

artery whose pulsation can be felt just in front of e targus of e ear.

Becomes > tortuous with increasing age & clearer in bold angry man.

Widely anastomoses with e facial artery.

ii. Vein: a branch of e internal jugular vein.

b. Auriculotemporal nerve: Branch of mandibular nerve. Passes backward from e

mandibular nerve at e bases of e skull.

Splits to enclose e middle meningeal artery.

Supplies e parotid gland, e temporal region, upper 2/3 of e skin of e external ear, A canal, & external surface of tympanic membrane with sensory fibers.

3. 2 structures deep to e muscle:a. 2 deep temporal nerves: branch of e

mandibular nerve.b. 2 deep temporal vessels: anterior &

posterior deep temporal arteries.

CONTENTS Communication:1. Superolaterally: with temporalis fossa,

deep to e zygomatic arch.2. Superomedially: with e orbits via

inferior orbital fissure.3. Above trough its roof: with middla

cranial fossa via foramen ovale & foramen spinosum.

4. Medially: with pterygo-palatine fossa. Contents:

1. Superficial:a. Lateral pterygoid muscle.b. Medial pterygoid muscle.c. Branches of e mandibular nerve.d. Maxillary arter (1st & 2nd parts):e. Pterygoid venous plexus:

2. Deep:a. Trunk of e mandibular nerve.

Trunk: meningeal branch & nerev to medial pterygoid.

Anterior division (mainly motor): masseteric & buccal nerves, nerve to lateral pterygoid, & 2 deep temporal nerves.

Posterior division (mainly sensory): auriculotemporal, lingual, & inferior areolar nerves.

b. Middle & accessory menigeal branch of e maxillary artery: Branch of e external carotid

artery which ends in e pterygo-palatine fossa as e sphenopalatine artery.

1st or mandibular part: horizontal & runs b/w sphenomandibular ligament & neck of e mandible.

2nd or pterygoid part: runs on e lower head of e lateral pterygoid muscle.

3rd or pterygo-palatine part: b/w 2 haeds of lateral pterygoid muscel & passes in e pterygomaxillary fissure to reach e pterygopalatine fossa.

c. Otic ganglion.d. Tensor palatine muscle.e. Chorda tempani.f. Spheno-mandibular ligament.g. Part of maxillary nerve.

3. Muscles of mastication: Develop from 1st pharyngeal arch. Arise from infratemporal aspect of e

skull. Inserted into e mandible.

Innervated by mandibular nerve. Act on TMJ. Concerned with chewing, grinding,

mastication, & speech. Send propiocephalic nucleus of e

midbrain.

Temporal fascia: Forms e roof of temporal fossa. Covers e temporalis muscle. Attaches superiorly to e superior

temporal line. Splits inferiorly into 2 layers which

attach to e lateral & medial surfaces of e arch.

Tethers e zygomatic arch superiorly. Provides resistance when e masseter

muscle contracts & exerts a downward pull on e zygomatic arch.

OTHERS

Zygomatic arch: It is formed by:

a. E temporal process of e zygomatic bone.

b. E zygomatic process of e temporal bone.

It is crossed by 3 nerves:a. Auriculotemporal nerve.b. Temporal branch of e facial nerve.c. Zygomatic branch of e facial nerve.

Structures passing deep to e arch:a. Descending: tendon of temporalis

muscle.b. Ascending: deep temporal vessels &

nerve. It gives attachment for 3 structures:

a. Temporal fascia.b. Masseter muscle.c. Superficial layer of e parotid capsule.

TEMPOROMANDIBULAR JOINT

PORTION TEMPOROMANDIBULAR JOINTOVERVIEW A modified hinge type of synovial joint: bicondylar synovial joint with intraarticular disc.

ARTICULAR SURFACE

Articular surface involved:1. E condyle of e mandible.2. E articular tubercle of e temporal bone. Not covered by hyaline cartilage but covered

with fibrocartilage.3. E mandibular fossa.

CAPSULE

E capsule is loose. It attaches to e:

1. Above: articualr tubercle & e margins of e mandibular fossa.2. Below: e neck of e mandible.

E thick part of e joint capsule: Forms e intrinsic lateral ligament which strengthen e TMJ laterally. Acts to prevent posterior dislocation of e joint with postglenoid tubercle.

LIGAMENTS

1. Lateral temporomandibular ligament: connects e mandible to e cranium.2. Stylomandibular ligament: thick band of e deep cervical fascia lying b/w e parotid &

submandibular glands.3. Sphenomandibular ligament: remnant of 1st pharyngeal-brachial arch.4. Functions:

a. Serves as swinging hinge for e mandible.b. Servs both as fulcrum & as a check ligament for e movement of e mandible.

INTRA-CAPSULAR

STRUCTURES

E synovial membranes:1. E superior synovial membrane: lines e fibrous layer of e capsule superior to e articular disc.2. E inferior synovial membrane: lines e fibrous layer of e capsule inferior to e articular disc.

E articular disc divides e TMJ into 2 separate compartments:1. Superior compartment: e gliding movements of protrusion & retrusion occur here.2. Inferior compartment: e hinge movements of depression & elevation occur here.

MOVEMENT TMJ movements r produced by chiefly by e muscles of mastication: Temporal, masseter, & medial & lateral pterygoid muscles). These muscles develop from e mesoderm of e embryonic 1st pharyngeal arch. Innervated by e motor root of e mandibular nerve.

E axis of rotation is e side of entry of e inferior alveolar nerve into e mandibular foramen in order to avoid stretching of that nerve.

E TMJ movements:1. Opening of e mouth:

Mainly acted by e lateral pterygoid muscles which pull e articular disc anteriorly. Assisted by suprahyoid muscles: digastrics, geniohyoid, & mylohyoid. E joint is very unstable in an opened mouth.

2. Closing of e mouth: Mainly by temporalis, masseter, & medial pterygoid muscles. Associated with e backward movement by e horizontal fibers of temporalis muscle.

3. Protraction: acted by lateral pterygoid muscles assisted by both medial pterygoid muscles.4. Retraction of e protruded mandible: acted by e posterior horizontal fibers of temporalis

muscle.5. Side to side movement: acted by lateral & medial pterygoid muscles of one side alternating

with those of e opposite side.

BLOOD & NERVE SUPPLY

1. Blood supply: a. Superficial temporal artery.b. Maxillary artery.

2. Nerve supply:a. Auriculotemporal nerve.b. Masseteric nerve: branch of mandibular nerve.

THE NOSE

PORTION DETAILS

OVERVIEW

E nose is e part of e respiratory tract superior to e hard palate which is vary in size & shape. It composed of e external nose & e nasal cavity. Functions:

1. Respiration. 3. Humidification of inspired air.2. Olfaction. 4. Receives secretion from e paranasal sinuses &

nasolacrimal ducts.

EXTERNAL NOSE

STRUCTURES

1. E dorsum: extends from e root of e nose to e apex (tip) of e nose.2. E nares or nostrils:

Also known as anterior nasal apertures. Bound medially by e nasal septum & laterally by a set of cartilages.

3. E alae: e wing of e nose.4. E vestibule of e nose:

E part of e external nose which is lined by skin & stiff hairs or vibrissae. E hair is moist to filter dust particles entering e nares. E junction of e skin & mucous membrane is beyond e hair-bearing area.

SKELETON

1. E bony part: Consists of:

a. Nasal bones.b. Frontal process of e maxillae.c. E nasal part of e frontal bone.d. Nasal spine.e. E bony part of nasal septum.

Covered by thin skin.

2. E cartilaginous (hyaline cartilage) part: Consists of:

a. 2 lateral cartilages.b. 2 alar cartilages.c. 1 septal cartilage.

Covered by thick skin which contains many sebaceous glands.

Upper 1/3 & lower 2/3 is flexible cartilage.

BLOOD & NERVE SUPPLY

Blood supply:1. Superior 1/3 of e nose: internal carotid artery → ophthalmic artery → dorsal nasal artery.2. Inferior 2/3 of e nose: internal carotid artery → ophthalmic artery → anterior ethmoidal

artery → external nasal artery → external carotid artery → facial artery → lateral nasal & septal branch.

Nerve supply:1. Infratrochlear nerve of V1.2. E external nasal nerve: an anterior ethmoidal branch V1.3. Infraorbital nerve of V2.

NASAL CAVITY

FEATURES

It extends anteriorly frome nostrils to e chonae posteriorly. E boundaries:

1. E anterior border: entered through e nares.2. E posterior border: opens into nasopharynx through choanae or poaterior nasal apertures.3. E roof:

Curved & narrow except at its posterior end. Divided into 3 parts: frontonasal, ethmoidal, & sphenoidal bones.

4. E floor: Wider than e roof. Formed by e palatine process of e maxilla & e horizontal plates of e palatine bone.

5. E medial wall: formed by nasal septum which divides e cavity into Rt. & Lt. halves.6. E lateral wall: nasal conchae.

E lining:1. Part lined by skin & hairs: e vestibule.2. Part lined by nasal mucosa:

Firmly bound to e periosteum & perichondrium of e supporting bones & cartilages of e nose.

E mucosa is continuous with e lining of all e chambers communicated to e cavity:a. Posteriorly: nasopharynx.b. Superiorly & laterally: paranasal sinuses.c. Superiorly: lacrimal sac & conjunctiva.

E nasal mucosa is divided into 2 parts:a. E respiratory area:

At e inferior 2/3 of e mucosa. Air passing over here is warmed & moistened before passes to e lung.

b. E olfactory area: At e superior 1/3 of e mucosa. Contains e peripheral organ of smell; sniffling draws air to this area.

NASAL SEPTUM

It divides e nasal cavity into Rt. & Lt. halves. Made of:

1. Bony part:a. E perpendicular plate of e ethmoid bone:

A thin bone forming e superior part of e nasal septum. Descends from e cribiform plate & is continued to this plate as e crista galli.

b. E vomer bone: A thin flat bone which forms e posteroinferior part of e nasal septum. Has some contribution from e nasal crests of e maxillary & palatine bones.

2. Cartilaginous part - e septal cartilage:

E only part made of cartilage. Has a tongue-and-groove articulation with e edge of e bony septum.

LATERAL WALL

1. E atrium: a depression in e front of e middle conchae.2. E vestibule: an area anterior & inferior to e atrium with stiff hairs inside e nares.3. 3 bony projections:

Called as turbinates or nasal conchae. They curve inferomedially, hanging like louvers or short curtains. They r highly convulated, scroll-like structures that offer a vast surface area for heat

exchange. They cause inspired air to be turbulent so as to facilitate e warming & humidifying action of e

mucous membrane. 3 conchae:

a. Superior nasal concha b. Middle nasal conchac. Inferior nasal concha:

E longest & broadest concha which is formed by an independent bone. Covered by a mucous membrane that contains large vascular spaces that can enlarge

to control e caliber of e nasal cavity.4. 5 passages or passageway:

a. Sphenoethmoidal recess: Lies superoposterior to e superior nasal concha. Receives e opening of e sphenoidal sinus.

b. Superior nasal meatus: A narrow passage b/w e superior & middle nasal conchae. Receives e opening from posterior ethmoidal sinus.

c. Middle nasal meatus: Longer & deeper than e superior nasal meatus. Receives e opening from frontal sinus (ethmoidal infundibulum → semilunar hiatus),

anterior ethmoidal cells (via semilunar hiatus), middle ethmoidal cells (around e ethmoidal bulla), & maxillary sinus (posterior end of semilunar hiatus).

E related structures:i. Ethmoidal bulla: a rounded elevation below e middle concha which is formed by e

projection of middle ethmoidal air cells.ii. Semilunar hiatus: a semicircular groove into which frontal sinus opens.iii. Infundibulum: a funnel-shaped opening located anterior to e hiatus which

communicates with e frontal sinus. d. Inferior nasal meatus: receives opening from nasolacrimal sac anteriorly.e. Common nasal meatus:

E medial part of e nasal cavity b/w e conchae e nasal septum. Receives opening from e lateral recesses & meatus.

BLOOD SUPPLY

1. Arterial supply: Derived mainly from branches of:

a. External carotid artery:i. Maxillary artery:

Sphenopalatine & greater palatine branches. Supply e posteroinferior part of e nasal cavity.

ii. Facial artery: Superior labia branch. Supplies e anteroinferior part of e nasal cavity.

b. Internal carotid artery: Anterior & posterior ethmoidal arteries of e ophthalmic artery. Supply e anterosuperior part of e nasal cavity.

Little’s area: Lower anterior part of e nasal septum where Kiesselbach’s plexus is located. A common site for epistaxis where 90% of bleeding episodes refer to this area. Kiesselbach’s plaexus: formed by e septal branches of:

a. Anterior & posterior ethmoidal arteries from ophthalmic artery.b. Superior labial artery from e facial artery.c. Sphenopalatine & greater palatine arteries from e maxillary artery.

2. Venous drainage: Rich venous plexuses in e nasal mucosa r drained by maxillary, facial, & ophthalmic veins. Facial vein has no valves, it has connections via e ophthalmic veins & pterygoid plexus with

cavernous sinus: angular & deep facial veins.3. Lymphatic drainage - drain into:

a. Submandibular LN.b. Retropharyngeal LN.c. Upper deep cervical LN.

NERVE SUPPLY

1. Olfactory nerve or CN1: olfactory mucosa.2. General sensation:

CN V1: anterior & posterior branches of nasocilliary nerve. CN V2: sphenopalatine & greater palatine branches.

3. Autonomic – parasympathetic: CN VII.

APPLIED ANATOMY1. Rhinitis, nasal polyps, & deviation of nasal septum.2. Cerebrospinal fluid (CSF) rhinorrhea: results from a fracture of e cribiform plate, teraing of e cranial meninges, &

Part of e ethmoid bone.

leakage of CSF from e nose.3. Foreign body & cancer.4. Epistaxis.5. Danger area:

A triangle drawn b/w e nasion & e Rt. & Lt. angles of e mouth. Infection in danger area can spread to cavernous sinus.

THE PARANASAL AIR SINUSES

PORTION DETAILS

OVERVIEW

E sinuses r air-filled cavities within e bones of e skull. They r lined with mucous membrane (extensions of e respiratory part of e nasal cavity) &

have connections with nasal cavity. E location depends & named according to e bones in which they reside.

FUNCTIONS

1. Humidifying & warming inspired air.2. Regulation of intranasal pressure.3. Increasing area for olfaction.4. Lightening e skull.

5. Acting as resonating chambers for e voice.

6. Absorbing shock.7. Contributing to e facial growth.

DEVELOPMENT

1. Rudimentary at birth: Maxillary, ethmoidal, & sphenoidal

sinuses. Rapid enlargement during 6 – 7 years

old & at puberty.

2. Absent at birth: Frontal sinuses which appears in 2nd

year of life. Rapid development during 6 – 7 years

& at puberty. Sometimes does not develop.

FRONTAL SINUSES

Appear at 2 years old. They r unequal in size & lie b/w orbit & anterior cranial fossa at e bony septum. Blood supply:

1. Arterial supply: supraorbital & supratrochlear arteries.2. Veinous drainage: diploic & superior ophthalmic veins.

Nerve supply: supraorbital & supratrochlear nerves. Lymph drainage: submandibular LN. Drainage: each frontal sinus opens in e infundibulum of e middle meatus through e

frontonasal duct. Vital anatomical structures in proximity – depending on its size:

1. Its floor may form e roof of e orbit.2. Its roof may form e floor of e anterior cranial fossa.

ETHMOIDAL SINUSES

Located in e ethmoid bone b/w e nasal cavities & e orbit on both e RT. & Lt. sides. On each side, 10 – 15 small cells r described in 3 groups:

1. E anterior ethmoidal cells: drain into e middle meatus through e infundibulum.2. E middle ethmoidal cells: open directly into e middle meatus.3. E posterior ethmoidal cells: open directly into e superior meatus.

Infection of e ethmoidal sinuse: Anatomical r/ship of e ethmoid sinuses to e eyes & brain r e reasons that untreated

severe sinusitis can lead to eye & brain complications. If drainage is blocked, infections of ethmoidal cells may break through fragile medial

wall of orbit. Severe infections from this source may cause blindness be some posterior ethmoidal

cells line close to e optic canal, gives passage to optic nerve & ophthalmic artery. Spread of infection from these cells also affects dural nerev sheath of optic nerve

results in optic neuritis.

SPHENOID SINUSES

Located in e body of sphenoid bone & may extend into e wings of this bone. They underlie e pituitary fossa. They open into e superior nasal meatus & sphenoethmoidal recess. Blood supply:

1. Posterior ethmoidal artery.2. Sphenopalatine artery.

Nerve supply: V1 – posterior ethmoidal & pteryngopalatine ganglion. Lymphatic drainage: retropharyngeal LN.

MAXILLARY SINUSES

They r pyramidal in shape & their anterior & posterior walls r e maxilla. They drain into e posterior hiatus semilunaris of middle meatus. Ostium is 3 – 4 mm high on e posterior end of nasal wall. They may be e 2nd ostium. They r e most difficult sinus to drain d/t e high position of its opening. Thus, it is inefficient

place from mechanical point of view. As a result, drainage is dependent one e effectiveness of e cilia lining. There r also one or more accessory openings. Relations:

Roof: formed by e floor of e orbit with infraorbital canal & nerve. Floor:

Formed by e alveolar process of maxilla with roots of at least e 1st & 2nd molars or may include canine, premolars, & molars.

Thus, tooth ache can be reffered to e maxillary sinus & floor may be perforated by one or > of e roots.

Vital anatomical structures in e proximity: infraorbital nerve (off of CN V2) & vessels, roots of maxillary molar teeth, superior alveolar nerves.

Branches of maxillary artery.

Clinical application:1. Unfortunate placement of maxillary ostium (located high on e superomedial walls):

Leads to poor drainage & plugged of maxillary ostia when e mucous membrane of e sinus is congested.

This is impossible for e sinuses to drain when e head is erect except they r full. To solve, it can be cannulated & drained by passing a cannula from nostril through

maxillary ostium into e sinus.2. When remove maxillary molar tooth, fracture of root may occur. If not retrieved, it may

drive a piece into e sinuses, making a communication b/w e mouth & maxillary sinuses, & infection can occur.

3. E superior alveolar nerves (branches of maxillary nerve) supply both e maxillary teeth & mucous membrane of maxillary sinuses. Thus, inflammation of mucosa of e sinuses is frequently accompanied by sensation of tootache in molar teeth.

4. Cancer of maxillary sinus.

THE EAR

PORTION DETAILS

EXTERNAL EAR

AURICLE

A handsome irregularly shaped plate of elastic cartilage that is covered by thin skin. It has several depression & elevations:

1. E concha: e deepest depression of auricle.2. E helix: e elevated margin of e auricle.3. E lobule: a non-cartilagenous earlobe consists of fibrous tissue, fat, & blood vessels.4. E tragus: a tongue-like projection overlapping e opening of e external acoustic meatus.

Function is to collect sound & lead it into EAM. E blood supply: posterior auricular & superficial temporal arteries. E nerve supply:

1. Cranial 0r medial surface & e posterior part of e lateral surface: great auricular nerve.2. E skin of e auricular anterior to e external acoustic meatus: e auriculotemporal nerve.

E lymphatic drainage:1. E lateral surface of e superior half of e auricle: superficial parotid LN.2. E cranial surface of e superior half of e auricle: mastoid & deep cervical LN.3. E remainder of e auricle & e lobule: superficial cervical LN.

EXTERNAL ACOUSTIC MEATUS

A pretty slightly S-shaped canal that leads inward through e tympanic part of e temporal bone from e auricle to e tympanic membrane which is 2 – 3 cm in adult.

2 parts:1. E lateral 1/3:

Cartilaginous & lined with skin that is continuous with e auricular skin. Contains ceruminous & sebaceous glands in its subcutaneous tissue that produce

ceruminax or earwax.2. E medial 2/3:

Bony & lined thin skin that is continuous with e external layer of e tympanic membrane. Any injury or inflammation here will lead to a great pain d/t e thn skin & very subcutaneous

bone. 2 common sites at which foreign bodies become lodged:

1. Isthmus: most foreign bodies lodge lateral to isthmus.2. Anterior recess: objects lodge here may not be readily visible on otoscopy because it is very

medial, near e tympanic membrane.

TYMPANIC MEMBRANE

A thin, oval, & semitransparent membrane of ~ 1 cm in diameter at e medial end of EAM. It forms a partition b/w EAM & e tympanic cavity of e middle ear. It is covered by:

1. External surface: thin skin of e EAM.2. Internal surface: mucous membrane of e middle ear.

It has 2 parts:1. E flaccid part:

Located superior to e lateral process of e malleus. Its membrane is thin & lacks e radial & circular fibers present in e other part. It forms e lateral wall of e superior recess of e tympanic cavity. In puncturing e tympanic membrane, flaccid part should be avoided because of e

underlying chorda tympani.2. E tense part: has many radial & circular fibers.

E tympanic membrane move sin response to air vibrations that pass to it through EAM. Nerve supply:

1. External surface: auriculotemporal nerve & small auricular branch of e vagus nerve.2. Internal surface: glossopharyngeal nerve.

MIDDLE EAR

OVERVIEW

E narrow air-filled chamber in e petrous part of e temporal bone. Functions:

1. Links e tympanic membrane to cochlea amplifying force or area.2. E muscles in it can dampen loud sound.

2 parts: 1. E tympanic cavity proper: e space directly internal to e tympanic membrane.2. E epitympanic recess: e space superior to e membrane.

Connection:1. Anteromedially connected to e nasopharynx via Eustachian’s tube.2. Posterosuperiorly with e mastoid cells via mastoid antrum.

BOUNDARIES 1. E roof – tegmen tympani: A thin plate of bone which is part of petrous temporal bone. Separates e tympanic cavity from e temporal lobe in middle cranial fossa.

2. E floor: formed by a thin plate of bone which separates e cavity from e superior bulb of internal jugular vein.

3. E lateral wall: e peaked convexity of e tympanic membrane.4. E medial wall: formed by e promontory of e inner ear which is related to e oval window or fenestra

vestibuli (above & behind) & round window or fenestra cochlea (below).5. E anterior boundary:

a. Carotid artery.b. Auditory tube below.c. Canal for tensor tympani muscle above.

6. E posterior boundary:

a. Upper part: aditus to mastoid antrum.b. Lower part: tendon of stapedius muscles & CN VII.

CONTENTS

1. Auditory ossicles: Form a mobile chain of small bones across e tympanic cavity from e tympanic membrane to e

oval window. E 1st bones to be fully ossified durinf development & r essentially mature at birth. E bone from which they r formed r very dense & hard. They r covered with e mucous membrane lining e tympanic cavity. They lack a surrounding layer of osteogenic periosteum. Consists of 3 bones: malleus, incus, & stapes. E bones increase e vibratory force for ~ 10 times but decrease e amplitude of e vibration

transmitted from e tympanic membrane. 2. Eustachian’s tube:

It connects e tympanic cavity to e nasopharynx, where it opens posterior to e inferior nasal meatus.

2 parts:a. Posterolateral third: bony.b. Anterolateral 2/3: cartilaginous.

Functions:a. Equalizes pressure in e middle ear with e atmospheric pressure, allowing free movement of

e tympanic membrane.b. Balances e pressure on both sides of e membrane by allowing air to enter & leave e

tympanic cavity.c. Usually in activities such as yawning & swallowing.

Blood supply:a. Arterial supply: ascending pharyngeal artery of ECA & e middle meningeal artery & artery

of e pterygoid canal, branches of maxillary artery.b. Venous supply: e pterygoid venous plexus.

Nerve supply: e tympanic plexus which is formed by fibers of e glossopharyngeal nerve & fibers from e pterygopalatine ganglion.

Lymphatic drainage: deep cervical LN.3. E muscles:

a. E tensor tympani muscle: Inserted into e malleus. It pulls e handle medially, tensing e tympanic membrane & reducing e amplitude of its

oscillations. Prevents damage to e inner ear when exposed to loud sound. Supplied by: mandibular nerve.

b. E stapedius muscle: A tiny muscle inside e pyramidal eminence on e posterior wall of e tympanic cavity. Inserted on e neck of e stapes. It pulls e stapes posteriorly & tilts its base in e oval window, thereby tightening e anular

ligament & reducing e oscillatory range. It prevents excessive movement of e stapes. Supplied by: facial nerve.

4. E mastoid antrum: A cavity in e mastoid process of e temporal bone. Separated from e middle cranial fossa by tegmen tympani. E antrum is e common cavity into which e mastoid cells opens. Lined with e mucous membrane that is continuous with e lining of e middle ear. Anteroinferiorly, it is related to e canal for facial nerve.

APPLIED ANATOMY

Complications of middle ear infection:1. Cerebral abscess.2. Extradural abscess.3. Subdural abscess.4. Cerebellar abscess.5. Thrombosis of simoid venous sinus.6. Meningitis.

INNER EAR

OVERVIEW

A fluid-filled chamber containing vestibulocochlear organs. Concerns with:

1. E reception of e sound.2. E maintenance of balance.

Referred pain to ear via auriculotemporal, glossopharyngeal, & vagus nerve.

CONTENTS 1. E bony labyrinth: cochlear, vestibule, & semicircular canal.2. E membranous labyrinth:

Also called e vestibular labyrinth. It has 2 functionally distinct subdivisions:

1. E static labyrinth: Otolith organ: utriculus & sacculus. E neuroepithelium of e ototith organ is e macula. Gravity is a form of linear acceleration. Serves as a plumb bob like reference for e head.

2. E dynamic labyrinth: E semicircular canal: duct & ampulla-containing neuroepithelium.

E neuroepithelium of e semicircular canal is called e crista ampullaris.

SOUND WAVE Sound wave → oval window → vestibule → scala vestibule → helicotrema → vestibular membrane → scala media →

basilar membrane → scala tympani → round window.

THE EYE & ORBIT

PORTION DETAILS

THE EYELIDS

OVERVIEW

E eyelid is a movable fold which is covered externally by thin skin & internally by transparent mucous membrane, e palpaberal conjunctiva.

It is e thinnest skin in e body & unique in having no subcutaneous fat layer. Upper eyelid is larger & > mobile compared to e lower eyelid.

Eyelid is divided by orbital septum into 2 parts:1. Anterior lamella: skin & orbicularis oculi muscle.2. Posterior lamella: conjunctiva, e tarsus septum, e levator palpebrae superioris, & e Muller

muscle. E functions:

1. Cover & protect e eyeball anteriorly from injury & excessive elight:a. Upper eyelid:

Eye opened & looked forward: covers upper margin of cornea. Eye closed: completely covers cornea.

b. Lower eyelid: Eye opened: lies just below cornea. Eye closed: rises only slightly.

2. Keep e cornea moist by spreading e lacrimal fluid.

CONJUNCTIVA

2 parts:1. E palpebral conjunctiva: thin & transparent & reflected onto e eyeball by attaching to e

anterior surface of e eyeball.2. E bulbar conjunctiva: lose & wrinkled over e sclera & adherent to e periphery of e cornea.

Conjunctival fornices: Deep recesses formed by e lines of reflection of e palpebral conjunctiva onto e eyeball. 2 parts: superior & inferior conjunctival fornices.

Conjunctival sac: E space bound by e palpebral & bulbar conjunctiva which is closed when e eyelids r closed,

but opens via an anterior aperture, e palpebral fissure when e eye is open. Is a specialized form of mucosal bursa that enables e eyelids to move freely over e surface of

e eyeball as they open & close.

TARSAL PLATE

Tarsal plate is a dense band of connective tissue which strengthened & forms e skeleton of e eyelids.

Fibers of e palpebral part of e orbicularis r in e connective tissue superficial to this plate & deep to e skin of e eyelid.

Embedded in this plate r e tarsal glands which r also known as Meibomian’s gland, a sebaceous gland.

E function is to produce lipid secretion which: Lubricates e edges of e eyelids. Prevents e eyelids from sticking together when they close. Forms a barrier that lacrimal fluid does not cross when produced in normal amount (when

production is excessive, it spills over e barrier into e cheeks as tears).

OTHER STRUCTURES

1. Eyelashes: located in e margins of e lids which r associated with large sebaceous glands called e ciliary gland or Gland of Zeis.

2. Angles of eye: Defined by e junctions of e superior & inferior eyelids that make up e medial & lateral

palpebral commissures. Each eye has medial & lateral angles called canthi.

3. Palpebral ligament:a. Medial palpebral ligament:

Located b/w e nose & e medial angle of e eye which connects e tarsal plate to e medial margn of e orbit.

E origin & insertion of orbicularis oculi.b. Lateral palpebral ligament: attaches e tarsal plate to e lateral margin of e orbit, but does not

provide for direct muscle attachment.4. Orbital septum:

A weak membrane acts as a fibrous frame work of e eyelid. It attaches to e margin of e orbit where it becomes continuous with e periosteum. It is thickened at e margin of e lids to form e tarsal plate. It keeps e orbital fat contained & can limit e spread of infection to & from e orbit.

MOVEMENT

E eyelids r closed by contraction of orbicularis oculi & relaxation of levator palpebrae superioris. Eye is opened by levator palpebrae superioris. On looking upward, levator palpebrae superioris contracts & upperlid moves with eyeball. On looking downward, both lids move, upper lid continue to cover e upper part of cornea &

lower lid is pulled down slightly by e conjunctiva which is attached to e sclera & lower lid.

NERVE SUPPLY 1. Ophthalmic division of V: supraorbital n., supratrochlear n., & lacrimal n.2. Maxillary division of V2: zygomaticofacial n., infraorbital n., & infratrochlear n.

APPLIED ANATOMY

1. Stye or Hordeolum: infection of Zeiss or Moll sebaceous gland.2. Chalazion: infection of Meibomian’s gland in e tarsal plate.

THE LACRIMAL APPARATUSSTURCTURES 1. Lacrimal glands:

Almond shaped & lies in e fossa for e lacrimal gland in e superolateral part of each orbit. Secrete lacrimal fluid, a watery physiological saline containing e bacteriocidal enzyme

lysozime. E fluid:

a. Moistens & lubricates e surfaces of e conjunctiva & cornea.b. Provides nutrients & dissolved oxygen to e cornea.c. Constitutes tears when excessively produced.

Accessory lacrimal glands r also present & they r numerous in e superior eyelid thain in e inferior eyelid such as Gland of Krause & Wolring gland.

2. Lacrimal ducts: E function is to convey lacrimal fluid (which flowa under e influence of gravity) from e

lacrimal glands to e conjunctival sac. There r 8 – 12 excretory ducts that open into e lateral part of e superior conjunctival fornix of

e conjunctival sac.3. Lacrimal canaliculi:

Commence at a lacrimal punctum on e lacrimal papilla near e medial angle of e eye. Drain lacrimal fluid from e lacrimal lake (a triangular space at e medila angle of e eye where

e tears collect) to e lacrimal sac (e dilated superior part of e nasolacrimal duct).4. Nasolacrimal duct: conveys e lacrimal fluid to e inferior nasal meatus.

NERVE SUPPLY

1. Presypnatic parasympathetic secremotor fibers r conveyed from facial nerve by e greater petrosal nerve & then by e nerve of pterygoid canal to e pterygopalatine ganglion.

2. Vasoconstrictive, postsynaptic sympathetic fibers brought from e superior cervical ganglion by e internal carotid plexus & deep petrosal nerve. Then join e parasympathetic fibers to form e nerve of pterygoid canal & transverse e pterygopalatine ganglion.

THE ORBIT

BONES

1. Roof:a. Orbital plate of frontal bone.b. Lesser wing of sphenoid.

2. Floor:a. Orbital plate of maxilla.b. Orbital surface of zygomatic.c. Orbital process of palatine.

3. Medial wall:a. Frontal process of maxilla.b. Lacrimal bone.c. Orbital plate of thinnest ethmoid (lamina

papyracea).d. Body of sphenoid.

4. Lateral wall:a. Zygomatic bone.b. Greater wing of sphenoid.

RELATION

1. Superior:a. Anterior cranial fossa.b. Frontal lobe.

2. Inferior: maxillary sinus.3. Medial:

a. Nasal cavity.b. Ethmoid sinus.c. Sphenoid sinus.

4. Lateral:a. Temporal fossa. Eyeballs r pointing forward.b. Middle cranial fossa.

EXTRA-OCULAR

MUSCLES

Muscle Innervation 1o action 2o action 3o actionMedial rectus

CN III

Adduction - -Superior rectus Elevation

AdductionIntorsion

Inferior rectus DepressionExtorsion

Inferior oblique ElevationAbduction

Superior oblique CN IV Depression IntorsionLateral rectus CN VI Abduction - -

Axis Muscle Others

Transverse axisSuperior oblique

DepressorInferior rectus

Vertical axisSuperior oblique

AbductorsInferior oblique

Anteroposterior axis

Inferior oblique 1. Lateral rotators2. ExtorsionInferior rectus

Inferior oblique 1. Intorsion2. Medial rotatorsInferior rectus

THE EYEBALLSFACIAL SHEATH

1. Tenon’s capsule or fascia bulbi: A thin fascial sheath of e eye closely surround e eyeball & separates it from orbital fat. Anteriorly, e sheath is attached to e sclera just behind e corneoscleral junction & its inner

layer blends with sclera. E outer layer pierced by tendons of 4 recti & 2 obliques & it extends back along them. Triangular expansions from e sleeves of medial & lateral recti form e medial & lateral check

Lateral wall slopes at 45o 2 medial walls r

parallel to each other

ligaments:a. Lateral check ligament attached to marginal tubercle of Whitnall.b. Medial check ligament attached to posterior lacrimal crest.

2. Suspensory ligament of Lockwood: inferior rectus is thickened on its underside & blends with e sleeve of inferior oblique as weel as check ligaments forming a hammock-like support for e eye.

3. Episcleral space: a potential space b/w e eyeball & e fascial sheath which allows e eyeball to move inside e cup-like sheath.

LAYERS

1. External tunic – fibrous layer:a. Sclera:

Tough, smooth fibroelastic connective tissue layer surrounding e eye. It is pierced by vessels & nerves. Its functions r to maintain e eye shape & for muscle attachment.

b. Cornea: Avascular, transparent layer over anterior eye. Aids in focusing light. Its irregularities lead to astigmatism.

2. Middle tunic – vascular layer:a. Choroid: highly vascular, pigmented dark reddish brown layer of eye which provides oxygens

& nutrients to other layers.b. Ciliary body:

Muscular & vascular which connects e choroid with e circumference of e iris. Functions:

Provides attachment for e lens. Contraction & relaxation of e smooth muscle of e ciliary body control thickness of e

lens. Allows lens to bulge under parasympathetic control.

c. Iris: A thin contractile diaphragm with a central aperture called e pupil for transmitting light. 2 involuntary muscles control e size of e pupil:

E parasympathetically stimulated sphincter papillae closes e pupil. E sympathetically stimulated dilator papillae opens e pupil.

3. Internal tunic – nervous layer: E inner layer is e retina which consists of 2 parts:

a. Optic part: Layer which is sensitive to visual light rays. Made up of 2 layers, e neural layer (light receptive) & e pigment cell layer (a single

layer cells that reinforces e light-absorbing property of e choroid in reducing e scattering of light in eyeball).

b. Non – visual part: an anterior continuation of e pigment cell layer & a layer of supporting cells over e ciliary body & e posterior surface of e iris.

Retinal filed: e region of e retina onto which e image is projected. Macula lutea & fovea centralis: high concentration of cones which is e area for e best vision. Peripheral retina: area with high concentration of rods which is sensitive to low level of

illumination & movement. Blood supply:

a. Arterial: central artery of retina.b. Venous: central veins which drain to superior ophthalmic veins.

Retina is attached to e choroid, outside e vitreous humour, & stops at ora serrata.

SEGMENTS

1. Posterior segment: segments of eye posterior to e back of e lens.2. Anterior segment: segment of e eye anterior to & including e lens:

a. Anterior chamber: E space b/w e cornea anteriorly & e iris/pupil posteriorly. Canal of Schlemm: circular modified venous structure in e anterior chamber angle that

drains aqueous to e aqueous veins.b. Posterior chamber: e space b/w e iris/pupil anteriorly & e lens & ciliary body posteriorly.

OTHERS

1. E fundus: e posterior part of e eyeball which has a circular depression called e optic disk where e sensory fibers & vessels conveyed by e optic nerve enter e eyeball through its centre.

2. Optic disc: e blind spot which contains no photoreceptors thus is sensitive to light. Just lateral to it is macula lutea.

3. Papilloedema: a non-inflammatory congestion of e optic disc, invariably associated with raised intracranial pressure.

THE MOUTH, TONGUE, & PALATES

PORTION DETAILS

MOUTH1. Mouth: from lips to palato-glossus arch (anterior pillars of fauces). 2. Floor of e mouth: e space occupied by e tongue.3. Roof of e mouth: e hard palate & soft palate.4. Lateral wall: cheeks & inner surface of teeth & gum. 5. Vestibule of e mouth: slit-like spaces where lips & cheeks lying b/w teeth & gum.6. Angle of e mouth: lies just in front of e 1st premolar tooth.7. Mouth cavity: e space inside e teeth & gum.8. E red transitional zone b/w the outer skin & inner mucous membrane of e lips is found only in man where hair

follicles and sweat glands r absent in this zone.

VESTIBULE

FEATURES

It is e space b/w e lips and cheeks & teeth and gum. E parotid duct opens on e mucous membranes of e cheeks opposite e 2nd upper molar tooth. Around e opening of e parotid duct, tiny molar glands open their ducts. Buccal & labial glands (mucous glands) r scattered in e vestibule, especially around e lower lip. Sub-mandibular and sublingual salivary glands open their ducts in the cavity of the mouth (not in

the vestibule).

NERVE SUPPLY

Nerve supply of e mucous membrane of lips & cheeks:1. Infra-orbital branch of maxillary: red marginal zone of e upper lip.2. Buccal branch of e mandibular nerve.3. Mental branch of inferior alveolar (from mandibular): for red marginal zone of e lower lip.

Nerve supply of the gum:1. Upper gum:

a. Superior alveolar nerve.b. Greater palatine nerve.c. Naso-palatine nerve.

TONGUE

PARTS

1. Posterior 1/3 – pharyngeal part: Post-sulcal part which is from sulcus erminlis to epiglottis. Known also as e root of e tongue or e base of e tongue. E function is for deglutition. E mucous membrane is smooth & contains lymphoid follicles (lingual tonsil –part of

Walddeyer’s ring). It faces backwards forming anterior wall of e oropharynx. If it is touched, leads to nausea. It contains mucous and serous glands.

2. Anterior 2/3 – oral part: Pre-sulcal part or e body of e tongue which extends from tip to sulcus terminalis. Function is for mastication. It is freely mobile & faces upwards against e hard palate. It fills most of e mouth cavity & is loosely attached to e floor of e mouth. It has stratified squamous keratinizing variety. Its dorsum contains no glands but contains papillae (filiform, fungiform, vallate) which

cause its mucous membrane to be rough.

SURFACES

1. Dorsum: Posterosuperiorly located, partly in oral cavity & partly in oropharynx. Characterized by a V-shaped groove which is called terminal sulcus. Shallow midline groove of e tongue:

Divides tongue into Rt. & Lt. side. Site of fusion of embryonic distal tongue bud.

2. Inferior surface: Covered with thin & transparent membrane through which one can see e underlying veins. Connected to e floor of mouth through frenulum which allowa e anterior part of e tongue to

move freely. Sublingual curuncle present on each side of frenulum base.

BLOOD SUPPLY

1. Arterial supply:a. Dorsal lingual artery: posterior part & palatine tonsil.b. Deep lingual artery: anterior part.

2. Venous drainage: a. Dorsal lingual vein: accompanies lingual artery.b. Deep lingual vein.

3. Lymphatic drainage:a. Superior deep cervical LN: posterior 1/3.b. Inferior deep cervical LN: medial part of anterior 2/3.c. Submandibular LN: lateral part of anterior 2/3.d. Submental LN: apex & frenulum.

NERVE SUPPLY

1. Motor: all muscles r supplied by CN XII or hypoglossal nerve except palatoglossus muscle which is supplied by pharyngeal plexus.

2. Sensation:1. General (touch):

Mucosa of anterior 2/3 supplied by lingual nerve, branch of CN V3. Mucosa of posterior 1/3 supplied by lingual branch of CN IX.

2. Special (taste): Mucosa of anterior 2/3 supplied by chorda tympani except vallate papillae. Mucosa of posterior 1/3 supplied by lingual branch of CN 9.

MUSCLE DESCRIPTION ORIGIN INSERTION INNERVATION ACTION

EXTRINSIC MUSCLESGENIO-GLOSSUS Fan-shaped

muscle, constitutes bulk of

tongue.

Superior genital spine of

mandible.

Dorsum of tongue & body

of hyoid.

Hypoglossus nerve (CN XII)

Protrudes apex of tongue through

mouth.

Branch of external carotid artery.

2. Lower gum:a. Inferior alveolar nerve.b. Buccal nerve. c. Lingual nerve.

HYO-GLOSSUS Thin, quadrilateral muscle.

Body & greater horn of hyoid

bone.Side & inferior

aspect of e tongue.

1. Depresses tongue.

2. Helps shorten tongue.

STYLO-GLOSSUS

Small, short, triangular muscle,

fibers interdigitate with

hyoglossus.

Styloid process & stylohyoid

ligament.

Draws tongue upward & backward.

PALATO-GLOSSUS

Narrow crescent- shaped palatine

muscle, acts as e boundary b/w

mouth & pharynx.

Palatine aponeurosis of

soft palate.

Side of tongue, blending with

intrinsic transverse

muscle.

Pharyngeal plexus.

1. Elevates posterior tongue or

depresses soft palate.

2. Constricts isthmus of

fauces.

INTRINSIC MUSCLES

SUPERIOR LONGITUDINAL

Thin layer deep to mucous

membrane of dorsum.

Submucous fibrous layer & medial fibrous

septum.

Margins of tongue & mucous

membrane.

Hypoglossal nerve (CN XII)

1. Curls tongue

longitudinally upward.

2. Elevates apex & sides of

tongue.3. Shortens

tongue.

INFERIOR LONGITUDINAL

Narrow band close to inferior surface.

Root of tongue & body ohf hyoid bone.

Apex of tongue.

1.Curls tongue longitudinally

downward.2.Depresses

apex.3.Shortens

tongue.

TRANSVERSE MUSCLE

Deep to superior longitudinal

muscle.

Median fibrous septum.

Fibrous tissue at lateral lingual

margins.

Narrows & elongates tongue.

VERTICAL MUSCLE

Fibers intersect transverse

muscle.

Submucous fibrous layer of

dorsum.

Interior surface of borders of

tongue.

Flattens & broadens tongue.

PARALINGUAL SPACE1. Location: deep to mylohyoid muscle which makes e dividing line b/w these 2 distinct spaces.2. Boundaries:

a. Lateral tongue including hyoglossus, styloglossus, & genioglossus.b. Hyoid bone.c. Oral mucosa.

3. Contents:a. Deep portion of submandibular gland. e. submandibular ganglion.b. Submandibular duct. f. hypoglossal nerve. c. Sublingual curuncle. g. sublingual gland & fold.d. Lingual nerve.

PLANE OF THE MOUTH1. Superficial to mylohyoid: submandibular gland.2. Superficial to hyoglossus:

a. Deep lobe of submandibular gland.b. Lingual nerve (CN III).c. Hypoglossal nerve (CN XII).d. Submandibular duct.e. Sublingual gland.

3. Deep to hyoglossus:a. Lingual artery.b. Glossopharyngeal nerve.c. Stylohyoid ligament.

APPLIED ANATOMY1. Gag reflex:

Parlysis of genio-glossus → tongue falls posteriorly → suffocation. In anasthaesia e muscles is totally relaxed, therefore inserting an “airway” is essential.

2. Fracture of mandible may lead to injury to e CN XII which causes atrophy of one side of e tongue. Thus, tongue will deviate towards e paralysed side during protrusion due to e action of e unaffected genioglossus of e other side.

3. Sublingual absorption of drug: (nitro-glycerine –vasodilator-) in angina. Drug will be absorbed by e deep lingual nerve in less than a minute.

4. Lingual carcinoma: common & metastasizes to submental & submandibular regions and along e inferior jugular

vein.5. Macro-glossia: big tongue.6. Micro-glossia: small tongue.7. Aglosia: absence of tongue. 8. Ankylo-glossia (adhesion): tongue tie.9. Exessive length of frenulum: can lead to suffocation.10. Bifid tongue (as in snakes tongue): double tongues.11. Trifid tongue: triple tongue.12. Congenital ligual cyst or thyroglossal cyst:

Remnant of thyroglossal duct. Lies just cranial to e hyoid bone (central in position) – can lead to dysphagia.

Lat ling swelling

Tuberculum impar

Foramen caecum

Copula

Hypobranchial eminence

Epiglotticeminence

Arytenoidswelling

Larygotracheal orifice

X X

IX IX

V VI