Anatomy of the Iliac Region

Iliac Crest

• The superior border of the ilium, plays a key role in connecting muscles and ligaments.
• Provides an attachment site for abdominal muscles and the latissimus dorsi.

Anterior Superior Iliac Spine (ASIS)

• A prominent bony landmark located at the front of the iliac crest.
• Important for muscle attachment, specifically the sartorius and tensor fasciae latae muscles.

Anterior Inferior Iliac Spine (AIIS)

• Located below the ASIS, serves as an attachment point for the rectus femoris muscle.
• Plays a role in stabilizing the pelvis during movement.

Posterior Superior Iliac Spine (PSIS)

• Found at the posterior end of the iliac crest, important for identification in anatomical landmarks.
• Involved in the alignment of the pelvis.

Posterior Inferior Iliac Spine (PIIS)

• Located below the PSIS, less prominent than its anterior counterpart.
• Functions as an attachment point for various pelvic muscles.

Greater Sciatic Notch

• A large indentation located posteriorly on the ilium, allows passage for the sciatic nerve.
• Crucial for the transition of structures between the pelvis and lower limb.

Acetabulum

• The cup-shaped socket of the hip joint formed by the fusion of the ilium, ischium, and pubis.
• Articulates with the head of the femur to form the hip joint.

Ischial Spine

• A pointed projection found on the ischium.
• Acts as an attachment point for the sacrospinous ligament and muscles.

Obturator Foramen

• A large opening formed by the ischium and pubis, mostly covered by the obturator membrane.
• Transmits the obturator nerve and vessels to the thigh.

Ischial Ramus

• The part of the ischium that extends towards the pubis.
• Contributes to the formation of the obturator foramen and supports pelvic structures.

Ischial Tuberosity

• A roughened, bony prominence on the ischium, serves as the sit bone.
• Provides support for weight-bearing when sitting and an attachment point for muscles.

Lesser Sciatic Notch

• A smaller indentation located inferior to the greater sciatic notch.
• Serves as a passageway for structures entering and leaving the pelvis.

Pubic Tubercle

• A prominence found on the superior part of the pubis.
• Important landmark for the attachment of ligaments, particularly the inguinal ligament.

Inferior Ramus of Pubis

• The segment of the pubis that extends downward and backward to join the ischium.
• Plays a crucial role in forming the pelvic ring.

Body of Pubis

• The central portion of the pubis, connecting the two pubic bones at the pubic symphysis.
• Involved in weight transfer and the stability of the pelvis.

Ala

• The wing-like part of the ilium, that broadens and flares laterally.
• Provides area for muscle attachment and helps create space for the pelvic cavity.

Ischial Body

• The main portion of the ischium, contributing to the structure and stability of the pelvis.
• Supports the body’s weight when in a sitting position and aids in locomotion.