What Is Hip Joint?

The hip joint is a ball-and-socket joint that connects the pelvis and the thighbones. The hip socket is called the acetabulum and actually forms a deep cup that surrounds the ball of the upper thighbone or femoral head. The surface of the femoral head and the inside of the acetabulum are covered with a smooth shiny cartilage that cushions, protects and at the same time allows near frictionless movement. Cartilage, which contains no nerve endings or blood supply, receives nutrients from a moisturizing lubricant (synovial fluid) produced by the synovial lining surrounding the hip joint. If damaged, the cartilage is not capable of repairing itself. Strong fibers (ligaments) connect the bones of the hip joint and provide necessary stability to the joint and elasticity for its movement. Muscles and tendons also play an important role in keeping the hip joint stable and mobile.