Osteoarthritis is a mechanical degenerative joint disease usually caused by age-related breakdown of joint cartilage
and underlying bone. Patients with osteoarthritis commonly present with stiffness and asymmetrical pain in weight-bearing joints that worsens with activity and improves with rest. Osteoarthritis is believed to be caused by mechanical stress on the joint and low grade inflammatory processes.
It develops as cartilage is lost and the underlying bone becomes affected. Joint findings include: osteophytes, joint space narrowing, and subchondral sclerosis and cysts.