BONES OF LOWER EXTREMITY

BONES OF LOWER BONES OF LOWER EXTREMITYEXTREMITY

PelvisPelvisThe pelvis is composed of three bones:The pelvis is composed of three bones:

IliumIliumIschiumIschiumPubisPubis

Pelvis: Lateral SurfacePelvis: Lateral SurfaceAcetabular fossa:Acetabular fossa:

For articulation with head of femur.For articulation with head of femur.Lunate surface.Lunate surface.

Acetabular notch.Acetabular notch.Acetabular labrum:Acetabular labrum:

Fibrocartilage rim around edge of Fibrocartilage rim around edge of acetabulum.acetabulum.

Pelvis: Lateral SurfacePelvis: Lateral SurfaceObturator foramen:Obturator foramen:

Covered by membrane.Covered by membrane.Passage for obturator nerve Passage for obturator nerve and vessels.and vessels.

Pelvis: Lateral SurfacePelvis: Lateral Surface Ischial ramus.Ischial ramus.Pubic rami:Pubic rami:

Superior.Superior.Inferior.Inferior.

Pubic tubercle:Pubic tubercle:Attachment for inguinal ligament.Attachment for inguinal ligament.

Pelvis: Anterior EdgePelvis: Anterior EdgeAnterior superior iliac spine (ASIS)Anterior superior iliac spine (ASIS)

Attachment of inguinal Attachment of inguinal ligament.ligament.

Proximal attachment for:Proximal attachment for:Sartorius muscle.Sartorius muscle.

Figure 3.3.Figure 3.3.

Pelvis: Anterior EdgePelvis: Anterior EdgeAnterior inferior iliac spine (AIIS):Anterior inferior iliac spine (AIIS):

Proximal attachment for:Proximal attachment for:Straight head of rectus femoris.Straight head of rectus femoris.

Pelvis: Posterior EdgePelvis: Posterior EdgePosterior superior iliac spine (PSIS).Posterior superior iliac spine (PSIS).Posterior inferior iliac spine (PIIS).Posterior inferior iliac spine (PIIS).Greater sciatic notch:Greater sciatic notch:

Converted into superior and inferior Converted into superior and inferior parts by piriformis muscle.parts by piriformis muscle.

Pelvis: Posterior EdgePelvis: Posterior EdgeLesser sciatic notch.Lesser sciatic notch. Ischial spine.Ischial spine. Ischial tuberosity.Ischial tuberosity.

Pelvis: Posterior LigamentsPelvis: Posterior LigamentsPosterior sacrospinous ligaments.Posterior sacrospinous ligaments.Sacrotuberous ligaments.Sacrotuberous ligaments.Sacrospinous ligaments.Sacrospinous ligaments.Figure 3.3.Figure 3.3.

Pelvis: Medial SurfacePelvis: Medial Surface Iliac fossa:Iliac fossa:

Attachment surface for iliacus muscle.Attachment surface for iliacus muscle.Arcuate line.Arcuate line.Auricular surface:Auricular surface:

Articulates with auricular surface of Articulates with auricular surface of sacrum.sacrum.

Pubic symphysis.Pubic symphysis.

SacrumSacrumConsists of 5 fused vertebrae.Consists of 5 fused vertebrae.Wing-like processes of each vertebra = Wing-like processes of each vertebra =

alae:alae:For attachment to ilium.For attachment to ilium.

Lip of body of first sacral vertebra = sacral Lip of body of first sacral vertebra = sacral promontory.promontory.

SacrumSacrumPosterior crests (Fig. 4.5):Posterior crests (Fig. 4.5):

Median crest:Median crest:Fused spinous processes.Fused spinous processes.

Intermediate crests:Intermediate crests:Fused articular (zygopophyseal) Fused articular (zygopophyseal)

processes.processes.

Lateral crests:Lateral crests:Fused transverse processes.Fused transverse processes.

Sacral hiatus.Sacral hiatus.

Lateral Pelvic Attachments

Medial Pelvic Attachments

Femur: Proximal AnteriorFemur: Proximal AnteriorHead.Head.Neck.Neck.Greater trochanter.Greater trochanter.Lesser trochanter.Lesser trochanter. Intertrochanteric line:Intertrochanteric line:

Low ridge connecting two trochanters.Low ridge connecting two trochanters.

Proximal Femur

Femur: Proximal PosteriorFemur: Proximal PosteriorHead.Head.Neck.Neck.Greater trochanter.Greater trochanter.Lesser trochanter:Lesser trochanter:

Projects backwards and medially.Projects backwards and medially.

Femur: Proximal PosteriorFemur: Proximal Posterior Intertrochanteric ridge:Intertrochanteric ridge:

High ridge connecting two trochanters.High ridge connecting two trochanters.Has quadrate tubercle:Has quadrate tubercle:Partial site of attachment for quadratus Partial site of attachment for quadratus

femoris muscle.femoris muscle.

Proximal Femur

Femur: Distal AnteriorFemur: Distal Anterior Medial and lateral condyles.Medial and lateral condyles. Medial and lateral epicondyles.Medial and lateral epicondyles. Patellar surface:Patellar surface:

Smooth, crescent surface between condyles.Smooth, crescent surface between condyles. Adductor tubercle:Adductor tubercle:

Small bump on medial epicondyle.Small bump on medial epicondyle.Site of partial attachment of adductor Site of partial attachment of adductor magnus.magnus.

Femur: Distal PosteriorFemur: Distal PosteriorMedial and lateral condyles.Medial and lateral condyles.Medial and lateral epicondyles.Medial and lateral epicondyles.Popliteal surface:Popliteal surface:

Smooth, triangular surface superior to Smooth, triangular surface superior to condyles.condyles.

Intercondylar fossa:Intercondylar fossa:Forms part of posterior boundary of Forms part of posterior boundary of

popliteal popliteal fossa.fossa.

Distal Femur

Femur: Posterior SurfaceFemur: Posterior Surface Linea asperaLinea aspera

Lateral boundary:Lateral boundary:Is a continuation of:Is a continuation of:

Gluteal tuberosity.Gluteal tuberosity.Inferiorly becomes:Inferiorly becomes:

Lateral supracondylar line.Lateral supracondylar line.Medial boundary:Medial boundary:

Is a continuation of:Is a continuation of:Pectineal line.Pectineal line.

Inferiorly becomes:Inferiorly becomes:Medial supracondylar line.Medial supracondylar line.

Tibia: Anterior ProximalTibia: Anterior ProximalMedial and lateral condyles.Medial and lateral condyles.Tuberosity.Tuberosity.Tubercles of intercondylar eminence.Tubercles of intercondylar eminence.

Tibia: Posterior ProximalTibia: Posterior ProximalMedial and lateral condyles.Medial and lateral condyles.Tubercles of intercondylar eminence.Tubercles of intercondylar eminence.Articular facet for fibula:Articular facet for fibula:

On inferior surface of lateral condyle.On inferior surface of lateral condyle.Soleal line:Soleal line:Shallow, rough ridge curving down from Shallow, rough ridge curving down from

lateral condyle.lateral condyle.

Tibia: DistalTibia: DistalAnterior distal surface:Anterior distal surface:

Medial malleolus.Medial malleolus.Lateral distal surface:Lateral distal surface:

Fibular notch.Fibular notch.

FibulaFibulaLies lateral to tibia.Lies lateral to tibia.Function:Function:

Involved in ankle joint.Involved in ankle joint.Muscle attachment.Muscle attachment.

Proximal end:Proximal end:Head.Head.Apex (styloid process).Apex (styloid process).Articular surface (facet) for lateral condyle Articular surface (facet) for lateral condyle

of of tibia.tibia.

FibulaFibulaDistal end:Distal end:

Lateral malleolus:Lateral malleolus:With articular surface for talus.With articular surface for talus.

Note:Note:Both tibia and fibula have interosseous Both tibia and fibula have interosseous

borders:borders:Face each other when the two bones are Face each other when the two bones are articulated.articulated.Site of attachment of interosseous Site of attachment of interosseous membrane.membrane.