Arthritis is the progressive degeneration of the cartilage surface of any joint.  Cartilage is the highly-specialized, smooth coating over the ends of bones in a joint that allows the joint to move easily and without pain.  Over time cartilage can begin to wear away (degenerate) resulting in loss of cartilage and eventual bone on bone contact of the joint.  Loss of cartilage results in pain, stiffness, decreased function, swelling, joint deformity and eventual immobility.  Unfortunately, with existing technology, cartilage cannot be replaced.  Early stages of arthritis can be treated with rest, activity modification, weight loss, anti-inflammatory medications, and steroid injections.  When these non-surgical treatments fail to alleviate symptoms, a total hip arthroplasty (joint replacement) is the most reliable, effective and long-term treatment for arthritis of the hip.