The Hip
A painful stiff hip compromises the ability to enjoy a full, active life. The most common cause is arthritis. Osteoarthritis occurs when firm cartilage material is worn away with normal wear and tear. Rheumatoid Arthritis is a disease of the lining around the hip, which causes destruction of the cartilage. Traumatic Arthritis results from previous injury, such as a hip fracture, which damages the joint surface. This sometimes leads to Osteonecrosis, in which the bone marrow dies because of a disrupted blood supply. Finally, arthritis can result from a change in the mechanical shape of the joint as a result of childhood developmental problems. These disorders include developmental dysplasia of the hip (DDH), Legg-Calve-Perthes disease (LCPD), and slipped capital femoral epiphysis (SCFE).

Anatomy
The hip joint is a ball and socket joint. It is where the round end of the thigh bone (the femoral head) joins with the hip socket (acetabulum). This arrangement allows a wide range of motion which permits activities such as walking, sitting, or squatting. The surfaces of the femoral head and the acetabulum are covered with cartilage: the thick, smooth, firm material that provides a gliding surface for the joint, which is lubricated by synovial fluid - not unlike motor oil for your car engine. Symptoms
Hip problems often begin with intermittent pain in the groin region while walking. Slowly, the hip becomes stiffer. It becomes increasingly difficult to put shoes and socks on, go up and down stairs, and get in and out of a car. Eventually, night pain may interfere with sleeping.

Diagnosis
The key to diagnosing arthritis of the hip is a thorough history and exam by an orthopedic surgeon. X-rays help to confirm the diagnosis, suggest possible causes, and indicate the severity of involvement. Occasionally, other tests such as blood tests or magnetic resonance imaging (MRI) are necessary to aid in the diagnosis.

Treatment Options
Not all arthritis of the hip requires surgical treatment. In fact, many patients are effectively treated with physical therapy and medication. There is a wide range of available medications. The mainstays of treatment are nonsteroidal anti-inflammatory drugs (NSAIDS) such as ibuprofen. Recently, a new generation of NSAIDS has produced selective cyclooxygenase (COX-2) inhibitors, which seem to be safer for one’s stomach. Some patients may require stronger medication such as prednisone. Other medications, such as oral glucosamine and chondroitin sulfate, have been shown in some studies to have an analgesic effect.

Surgical treatment of the arthritic hip varies from arthroscopy to osteotomy (cutting and reorienting the bone) to the most common treatment - hip replacement. In fact, more than 160,000 hip replacements are performed each year in the United States alone!

Hip Replacement Surgery
The goal of hip replacement surgery is to relieve pain and improve mobility and function. During the surgery, the diseased bone is replaced with an artificial implant. There are two major techniques. One method is to cement the implant to the bone. This allows a patient to place weight on the hip immediately following the surgery. However, should the hip ever fail and need to be revised, this cement can be difficult to extract. The other option is a cementless implant, which allows the bone to attach itself directly to the implant. This takes time, however, and frequently the patient will have to limit weight-bearing for six weeks or longer. Important issues such as the type of implant, bearing surfaces, leg length differences, hip dislocation, risk of blood clots in the legs and pulmonary embolism, and blood donation can be discussed at further length with your orthopedic joint surgeon.

Conclusion
Hip arthritis is common, painful, and disabling. When severe, hip replacement surgery can clearly provide significant improvement in functional status and quality of life.