Do a lot of people get synovitis?

Yes. Synovitis is inflammation of the lining of a joint. It can occur as a result of injury, infection, joint degeneration, or autoimmune conditions usch as rheumatoid arthritis. Common symptoms of synovitis are joint pain, fluid accumulation in the joint, and stiffness. Treatment of symptoms includes anti-inflammatory medications or intra-articular steroid injections.