The hip joint is a ball and socket synovial joint that connects the femur to the acetabulum. It is the largest and most stable joint in the body. The hip joint allows for flexion, extension, abduction, adduction, and rotation. Several strong ligaments reinforce the hip joint capsule to provide stability, including the iliofemoral, ischiofemoral, and pubofemoral ligaments. The main muscles that act on the hip joint are the gluteal muscles, iliopsoas, quadriceps femoris, hamstrings, and adductors.