Osteoarthritis is the gradual breakdown of the material, called cartilage, that covers the joint. Cartilage is a tough elastic material that acts as a shock absorber. In osteoarthritis, the cartilage becomes thinner and may even disappear in some places. When this happens, bone rubs against bone, causing pain. Under this weakened cartilage, the bone tries to regenerate and forms growths, called spurs or osteophytes. The joint may become deformed, larger, and lose its mobility.

Although we still have a lot to learn about the causes of osteoarthritis of the hip, we do know that it is more common in people over the age of 45, after a joint injury caused by an accident, sports injury or physical labour, under certain hereditary conditions, or as a result of certain diseases that change the characteristics of the cartilage or the shape of the joint. The hip is a complex joint where the head of the femur, which is the thighbone, attaches to the pelvic girdle.

Normal	Diseased
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The symptoms appear gradually. The pain is felt in the groin and the inner part of the thigh. Sometimes it can be felt in the buttocks and the sciatic area. The pain first occurs with mobilization (movement) of the joint, and then, depending on the duration and seriousness of the osteoarthritis, it may even occur at rest or at night. There may be stiffness in the morning when you get up or after a period of inactivity. Loss of range of motion may make it difficult to walk, stand, sit, stand up, go up and down stairs, and put on your shoes and socks. You may develop a limp, and sexual relations may be painful.