Child and Adult Hip Preservation Program
Your hip joint
The hip joint is one of the body's most reliable structures, providing movement and support without pain or problem in most people for a lifetime. The hip's simple ball and socket arrangement, with the ball shaped femoral head rotating inside a cup shaped socket, the acetabulum, usually works well for many decades of a lifetime with amazingly little friction and little or no wear.
The well fitting surfaces of the femoral head and acetabulum which face each other, are lined with a layer of cartilage, lubricated by a thin film of synovial fluid. Friction inside a normal hip is less than 1/10 that of ice gliding on ice.
There are two types of cartilage that are found in the hip joint:
- Articular cartilage is found on the head of the femur and also lines the inner surface of the acetabulum. This cartilage provides a smooth contact surface which allows the femoral head to move smoothly within the acetabulum.
- The labrum is a rim of fibrous cartilage which lines the outer edge of the acetabulum. This cartilage serves to stabilize and cushion the hip joint.

