The hip is a ball-and-socket joint. The socket is formed by the acetabulum, which is part of the large pelvis bone. The ball is the femoral head, which is the upper end of the femur (thighbone). A slippery tissue called articular cartilage covers the surface of the ball and the socket. It creates a smooth, frictionless surface that helps the bones glide easily across each other. The acetabulum is ringed by strong fibrocartilage called the labrum which forms a gasket around the socket. The joint is surrounded by bands of tissue called ligaments. They form a capsule that holds the joint together. The interior of the capsule is lined by a thin membrane called the synovium. It produces synovial fluid that lubricates the joint.
If your hip has been damaged by arthritis, a fracture, or other conditions, common activities such as walking or getting in and out of a chair may be painful and difficult. Your hip may be stiff, and it may be hard to put on your shoes and socks. You may even feel uncomfortable while resting.
If medications, changes in your everyday activities, and the use of walking supports do not adequately help your symptoms, you may consider hip replacement surgery. Hip replacement surgery is a safe and effective procedure that can relieve your pain, increase motion, and help you get back to enjoying normal, everyday activities.
First performed in 1960, hip replacement surgery is one of the most successful operations in all of medicine. Since 1960, improvements in joint replacement surgical techniques and technology have greatly increased the effectiveness of total hip replacement. According to the Agency for Healthcare Research and Quality, more than 285,000 total hip replacements are performed each year in the United States.
In a total hip replacement (also called total hip arthroplasty), the damaged bone and cartilage is removed and replaced with prosthetic components.
- The damaged femoral head is removed and replaced with a metal stem that is placed into the hollow center of the femur. The femoral stem may be either cemented or “press fit” into the bone
- A metal or ceramic ball is placed on the upper part of the stem. This ball replaces the damaged femoral head that was removed
- The damaged cartilage surface of the socket (acetabulum) is removed and replaced with a metal socket. Screws or cement are sometimes used to hold the socket in place
- A plastic, ceramic, or metal liner is inserted between the metal socket to allow for a smooth gliding surface for the ball to move within
Osteoarthritis: This is an age-related “wear and tear” type of arthritis. It usually occurs in people 50 years of age and older and often in individuals with a family history of arthritis. The cartilage cushioning the bones of the hip wears away. The bones then rub against each other, causing hip pain and stiffness. Osteoarthritis may also be caused or accelerated by subtle irregularities in how the hip developed in childhood.
Rheumatoid arthritis: This is an autoimmune disease in which the synovial membrane becomes inflamed and thickened. This chronic inflammation can damage the cartilage, leading to pain and stiffness. Rheumatoid arthritis is the most common type of a group of disorders termed “inflammatory arthritis.”
Post-traumatic arthritis. This can follow a serious hip injury or fracture. The cartilage may become damaged and lead to hip pain and stiffness over time.
Avascular necrosis: This occurs when an injury to the hip, such as a dislocation or fracture, limits the blood supply to the femoral head. The lack of blood may cause the surface of the bone to collapse, and arthritis will result. Some diseases can also cause avascular necrosis.
Childhood hip disease: Some infants and children have hip problems that though successfully treated may still cause arthritis later in life. This occurs because the hip doesnot grow normally, and the joint surfaces are affected.