Anterior rim of acetabulum

The anterior rim of the acetabulum is formed by the osseous contributions of the pubis and ilium. The anterior rim extends from the anterior inferior iliac spine (AIIS) superiorly, curving inferiorly toward the pubic bone, and is characterized by several key features:

• The anterior wall is composed of the pubic portion of the acetabulum.

• The anterior rim is not a uniform curve but displays a wave-like profile with prominences and depressions. Notably, the anterosuperior region is a common site for labral pathology and is biomechanically significant.[2-3]

• The psoas valley is a distinct depression at the anterosuperior rim, over which the iliopsoas tendon passes. This valley is typically curved and is located just inferior to the AIIS, with a mean depth of approximately 5 mm below the acetabular equator.

• The anterior labral sulcus is a reliable arthroscopic landmark at the superior margin of the anterior rim, corresponding to the 3 o’clock position on the acetabular clockface.

• The lunate surface of the acetabulum, which is the articular cartilage, is interrupted anreroinferioriorly by the acetabular notch and the attachment of the transverse acetabular ligament.