Download The pelvis is composed of three bones

BONES OF LOWER
EXTREMITY
Pelvis

The pelvis is composed of three bones:
Ilium
Ischium
Pubis
Pelvis: Lateral Surface

Acetabular fossa:
For articulation with head of femur.
Lunate surface.
Acetabular notch.
 Acetabular labrum:

Fibrocartilage rim around edge of
acetabulum.
Pelvis: Lateral Surface

Obturator foramen:
Covered by membrane.
Passage for obturator nerve and vessels.
Pelvis: Lateral Surface
Ischial ramus.
 Pubic rami:

Superior.
Inferior.

Pubic tubercle:
Attachment for inguinal ligament.
Pelvis: Anterior Edge

Anterior superior iliac spine (ASIS)
Attachment of inguinal
ligament.
Proximal attachment for:
Sartorius muscle.

Figure 3.3.
Pelvis: Anterior Edge

Anterior inferior iliac spine (AIIS):
Proximal attachment for:
Straight head of rectus femoris.
Pelvis: Posterior Edge
Posterior superior iliac spine (PSIS).
 Posterior inferior iliac spine (PIIS).
 Greater sciatic notch:

Converted into superior and inferior
parts by piriformis muscle.
Pelvis: Posterior Edge
Lesser sciatic notch.
 Ischial spine.
 Ischial tuberosity.

Pelvis: Posterior Ligaments
Posterior sacrospinous ligaments.
 Sacrotuberous ligaments.
 Sacrospinous ligaments.
 Figure 3.3.

Pelvis: Medial Surface

Iliac fossa:
Attachment surface for iliacus muscle.
Arcuate line.
 Auricular surface:

Articulates with auricular surface of
sacrum.

Pubic symphysis.
Sacrum
Consists of 5 fused vertebrae.
 Wing-like processes of each vertebra =
alae:
For attachment to ilium.
 Lip of body of first sacral vertebra = sacral
promontory.

Sacrum

Posterior crests (Fig. 4.5):
Median crest:
Fused spinous processes.
Intermediate crests:
Fused articular (zygopophyseal) processes.
Lateral crests:
Fused transverse processes.

Sacral hiatus.
Lateral Pelvic Attachments
Medial Pelvic Attachments
Femur: Proximal Anterior
Head.
 Neck.
 Greater trochanter.
 Lesser trochanter.
 Intertrochanteric line:

Low ridge connecting two trochanters.
Proximal Femur
Femur: Proximal Posterior
Head.
 Neck.
 Greater trochanter.
 Lesser trochanter:

Projects backwards and medially.
Femur: Proximal Posterior

Intertrochanteric ridge:
High ridge connecting two trochanters.
Has quadrate tubercle:
Partial site of attachment for quadratus
femoris muscle.
Proximal Femur
Femur: Distal Anterior
Medial and lateral condyles.
 Medial and lateral epicondyles.
 Patellar surface:

Smooth, crescent surface between condyles.

Adductor tubercle:
Small bump on medial epicondyle.
Site of partial attachment of adductor
magnus.
Femur: Distal Posterior
Medial and lateral condyles.
 Medial and lateral epicondyles.
 Popliteal surface:

Smooth, triangular surface superior to
condyles.

Intercondylar fossa:
Forms part of posterior boundary of popliteal
fossa.
Distal Femur
Femur: Posterior Surface

Linea aspera
Lateral boundary:
Is a continuation of:
Gluteal tuberosity.
Inferiorly becomes:
Lateral supracondylar line.
Medial boundary:
Is a continuation of:
Pectineal line.
Inferiorly becomes:
Medial supracondylar line.
Tibia: Anterior Proximal
Medial and lateral condyles.
 Tuberosity.
 Tubercles of intercondylar eminence.

Tibia: Posterior Proximal
Medial and lateral condyles.
 Tubercles of intercondylar eminence.
 Articular facet for fibula:

On inferior surface of lateral condyle.
Soleal line:
Shallow, rough ridge curving down from
lateral condyle.
Tibia: Distal

Anterior distal surface:
Medial malleolus.

Lateral distal surface:
Fibular notch.
Fibula
Lies lateral to tibia.
 Function:

Involved in ankle joint.
Muscle attachment.

Proximal end:
Head.
Apex (styloid process).
Articular surface (facet) for lateral condyle of
tibia.
Fibula

Distal end:
Lateral malleolus:
With articular surface for talus.

Note:
Both tibia and fibula have interosseous
borders:
Face each other when the two bones are
articulated.
Site of attachment of interosseous
membrane.