Superior rim of acetabulum

The superior rim of the acetabulum is the uppermost margin of the acetabular margin (acetabular cup), forming the weight-bearing portion of the hip socket. It is primarily formed by the ilium and is characterized by a wave-like, asymmetric profile with distinct prominences and depressions. The superior rim includes the acetabular roof (also known as the "sourcil"), which is the thickest and strongest part, supporting the majority of the load transmitted through the femoral head during standing and gait.

The labrum, a fibrocartilaginous structure, attaches circumferentially to the rim, deepening the socket and contributing to joint stability.The superior rim is also closely related to the attachment of the joint capsule and the origin of the rectus femoris muscle near the anterior inferior iliac spine.