Acetabulus

Acetabulus, also known as acetabulum, is a term used in anatomy to describe the cup-shaped socket in the pelvis where the head of the femur (thighbone) articulates. It is a crucial part of the hip joint, providing stability and allowing for a wide range of motion. The acetabulum is part of the os coxae, or hip bone, and is located in the acetabular fossa, a depression in the pelvic bone.

The acetabulum has a distinctive shape, with a shallow concave surface that fits snugly around the femoral head. This shape is maintained by the acetabular labrum, a fibrocartilaginous rim that surrounds the acetabulum. The labrum deepens the socket and helps to distribute the forces of weight-bearing and movement.

The acetabulum is lined with hyaline cartilage, which provides a smooth surface for articulation with the femoral head. This cartilage is covered by a layer of synovium, which produces synovial fluid that lubricates the joint and nourishes the cartilage.

The acetabulum is a complex structure that plays a vital role in the function of the hip joint. Its unique shape and the surrounding structures work together to provide stability, support, and mobility. Any abnormalities or injuries to the acetabulum can lead to pain, instability, or limited range of motion in the hip.