Lunate surface of acetabulum

Lunate surface of acetabulum is a crucial anatomical feature located within the pelvis, specifically part of the acetabulum, which plays a significant role in the hip joint's structure and function. The acetabulum is a concave socket on the lateral aspect of the pelvis that articulates with the femoral head, forming the hip joint. The lunate surface is the smooth, crescent-shaped articular surface within the acetabulum that directly contacts the femoral head.

Anatomy

The lunate surface is bordered by the acetabular notch inferiorly and extends to the acetabular fossa, which is non-articular. This surface is covered by hyaline cartilage in the living body, which is crucial for reducing friction and distributing load in the hip joint. The rest of the acetabulum, not covered by the lunate surface, includes areas that serve for the attachment of ligaments and the acetabular labrum, a fibrocartilaginous structure that deepens the socket and enhances joint stability.

Function

The primary function of the lunate surface is to facilitate smooth movement of the femoral head within the acetabulum, allowing for a wide range of motion in the hip joint including flexion, extension, abduction, adduction, and rotational movements. The integrity of the lunate surface is vital for the proper biomechanics of the hip joint, and damage to this area can lead to joint instability, pain, and decreased range of motion.

Clinical Significance

Conditions such as osteoarthritis can lead to the degeneration of the lunate surface, resulting in pain and impaired movement. In cases of severe damage or degeneration, surgical interventions such as total hip arthroplasty (hip replacement) may be necessary to restore function. During such procedures, the damaged lunate surface is replaced with artificial materials designed to mimic the natural articulation of the hip joint.

See Also

• Acetabulum
• Hip joint
• Femoral head
• Osteoarthritis
• Total hip arthroplasty