The Hip. Pelvic (Hip) Girdle Two hip bones (each also called coxal bone or os coxae) – Attach the lower limbs to the axial skeleton with strong ligaments.

The Hip

Pelvic (Hip) Girdle• Two hip bones (each also called coxal

bone or os coxae)–Attach the lower limbs to the axial

skeleton with strong ligaments–Transmit weight of upper body to

lower limbs–Support pelvic organs

Os coxae

• Each hip bone consists of three fused bones: ilium, ischium, and pubis

• Together with the sacrum and the coccyx, these bones form the bony pelvis

Figure 7.29

Coxalbone(os coxaeor hip bone)

llium

Sacroiliacjoint

Iliac fossa

Pubicbone

Ischium

Sacrum

Base of sacrum

Sacralpromontory

Pelvic brim

Acetabulum

Pubic crestPubic symphysis

Iliac crest

Coccyx

Pubic arch

Anterior inferioriliac spine

Anteriorsuperior iliac spine

Pubic tubercle

PLAY Animation: Rotatable pelvis

Hip Bone• Three regions

1. Ilium• Superior region of the coxal bone• Auricular surface articulates with the sacrum (sacroiliac

joint)2. Ischium

• Posteroinferior part of hip bone3. Pubis

• Anterior portion of hip bone• Midline pubic symphysis joint

Anterior Superior Iliac Spine

Acetabulum

Ischial tuberosity

Figure 7.30a

Ilium

Posterior gluteal line*PosteriorsuperioriIiac spine

Greater sciaticnotch

Posterior inferioriliac spine*

Ischial bodyIschial spineLesser sciatic notch

Ischialtuberosity

Ischium

Ischial ramus Obturator foramen

Inferiorgluteal line

Acetabulum

Pubic body

Iliac crest

Anteriorsuperioriliac spine

Anterior inferioriliac spine*

Pubis

Inferior ramusof pubis*

(a) Lateral view, right hip bone

Figure 7.30b

Iliac fossa

Ilium

Iliac crest

Anteriorsuperioriliac spine

Anterior inferioriliac spine*

Pubic tubercle

Inferior ramusof pubis

Posteriorsuperioriliac spine

Obturatorforamen

Body ofthe ilium

Ischium

Ischial ramus

(b) Medial view, right hip bone

Ischial spine*Lesser sciatic notch

Greater sciatic notch

Posteriorinferioriliac spine

Articular surfaceof pubis (at pubic symphysis)*

Comparison of Male and Female Pelves

• Female pelvis– Adapted for childbearing– True pelvis (inferior to pelvic brim) defines birth

canal– Cavity of the true pelvis is broad, shallow, and has

greater capacity

Comparison of Male and Female Pelves

• Male pelvis– Tilted less forward– Adapted for support of male’s heavier build and

stronger muscles– Cavity of true pelvis is narrow and deep

A man’s hip

Comparison of Male and Female PelvesCharacteristic Female Male

Bone thickness Lighter, thinner, and smoother

Heavier, thicker, and more prominent markings

Pubic arch/angle 80˚– 90˚ 50˚– 60˚

Acetabula Small; farther apart Large; closer together

Sacrum Wider, shorter; sacral curvature is accentuated

Narrow, longer; sacral promontory more ventral

Coccyx More movable; straighter Less movable; curves ventrally

Table 7.4

Table 7.4

Table 7.4

The Lower Limb

• Carries the weight of the body• Subjected to exceptional forces • Three segments of the lower limb

– Thigh: femur– Leg: tibia and fibula– Foot: 7 tarsal bones in the ankle, 5 metatarsal

bones in the metatarsus, and 14 phalanges in the toes

Femur

• Largest and strongest bone in the body• Articulates proximally with the acetabulum of

the hip and distally with the tibia and patella

Figure 7.31

Neck Foveacapitis

Greatertrochanter

Inter-trochantericcrest

Head

Intertrochantericline

Lesser trochanter

Gluteal tuberosity

Linea aspera

Lateralcondyle

LateralepicondyleIntercondylar fossa

Medial andlateral supra-condylar lines

Medial condyle

Medialepicondyle

Adductortubercle

Anterior view Posterior view(b) Femur (thigh bone)

Lateral epicondyle

Patellar surface

Posterior

Facet formedialcondyleof femur

Facet for lateralcondyle of femur

Surface forpatellarligament

ApexAnterior

(a) Patella (kneecap)

Bones of the LegTibia• Medial leg bone• Receives the weight of the body from the

femur and transmits it to the foot

Bones of the legFibula• Not weight bearing; no articulation with

femur• Site of muscle attachment • Connected to tibia by interosseous

membrane• Articulates with tibia via proximal and

distal tibiofibular joints

Figure 7.32a

Medial condyle

Articular surface

Tibial tuberosity

Interosseous membrane

Anterior border

Tibia

Medial malleolus

Intercondylar eminence

Proximal tibiofibularjoint

Distal tibiofibularjoint

Lateral malleolus

Lateral condyle

Fibula

Head

(a) Anterior view

Figure 7.32b

Medial condyle

Articular surface oflateral condyle

Articular surfaceof medial condyle

Articular surface

Interosseousmembrane

Tibia Fibula

Head of fibula

Medial malleolusLateral malleolus

(b) Posterior view

Foot: Tarsals

• Seven tarsal bones form the posterior half of the foot

• Talus transfers most of the weight from the tibia to the calcaneus

• Other tarsal bones: cuboid, navicular, and the medial, intermediate, and lateral cuneiforms

Foot: Metatarsals and Phalanges

• Metatarsals:– Five metatarsal bones (#1 to #5) – Enlarged head of metatarsal 1 forms the “ball of the foot”

• Phalanges– The 14 bones of the toes– Each digit (except the hallux) has three phalanges – Hallux has no middle phalanx

Figure 7.33a

Medialcuneiform

Phalanges

Metatarsals

TarsalsNavicular

Intermediatecuneiform

Talus

Calcaneus(a) Superior view

Cuboid

Lateralcuneiform

Proximal54321

Middle

Distal

Trochleaof talus

Figure 7.33b

Facet formedialmalleolus

Calcanealtuberosity(b) Medial view

Intermediatecuneiform Sustentac-

ulum tali(talar shelf)

Talus

Navicular

First metatarsal

Medialcuneiform

Calcaneus

PLAY Animation: Rotatable bones of the foot

Arches of the Foot

• Arches are maintained by interlocking foot bones, ligaments, and tendons

• Arches allow the foot to bear weight• Three arches

– Lateral longitudinal – Medial longitudinal – Transverse

Figure 7.34a

Medial longitudinalarch

Transverse arch

Laterallongitudinal arch

(a) Lateral aspect of right foot

Developmental Aspects: Fetal Skull

• Infant skull has more bones than the adult skull• Skull bones such as the mandible and frontal bones are

unfused • At birth, skull bones are connected by fontanelles

– Fontanelles• Unossified remnants of fibrous membranes between

fetal skull bones• Four fontanelles

– Anterior, posterior, mastoid, and sphenoid