The hip joint is comprised of a ball (femoral head), which sits at the end of the femur (thigh bone), while the socket (acetabulum) is part of the pelvis. Articular cartilage covering the head of the femur (thigh bone) and the inner surface of the socket ensures that the joint surfaces can easily slide against one another.

Running along the rim of the socket is an area of soft tissue or cartilage known as the labrum. Its function is to improve joint stability by keeping the ball portion of the femur inside the socket.