As the joint starts to wear out, the surface of the joint becomes irregular, and the muscle wastes away due to pain and disuse.
Stiffness occurs due to inflammation and pain associated with movement.
In the earlier stages of osteoarthritis, rehabilitation may provide significant benefit. Rehabilitation for arthritis focuses on range of motion to the joint and strengthening the muscles around the joint. Exercises that are particularly beneficial are bicycling and swimming. Bicycling at high revolution and low resistance acts to lubricate the joint and smooth the joint surfaces as they rub together. At least 20 minutes a day on a stationary bicycle is recommended.