The hip is a ball-and-socket joint. The ball moves in the socket, allowing the leg to rotate and move forward, backward and sideways. As an individual ages, it is common for the cartilage (thin tissue that covers bone surfaces providing smooth, friction-free movement) in the hip joint to wear down. Degenerative hip joint changes can cause symptoms such as pain, stiffness, swelling around the joint, tenderness, limited range of motion, or a sensation of catching or grinding in the joint with movement.