Inflammatory arthritic conditions affecting the rheumatoid knee joint may be complicated by the development of popliteal cysts. We describe 4 RA patients who presented with ruptured cysts. Patients were 2 males and 2 females. All were outpatients and their ages at the time of rupture ranged from 43 to 61 years. Duration of RA ranged from 7 to 31 years. They presented with acute pain and swelling around the knee in accordance with increasing inflammatory indices. All patients were treated conservatively at the begining. One patient's is popliteal complaint improved following an intra-articular corticosteroid injection. The other patients remained symptomatic and underwent surgery. One patient with a markedly degenerated knee joint underwent total knee arthroplasty. We performed cystectomy and anterior synovectomy on the other 2 patients. There were no relapses of popliteal cysts in any patients. It is important to treat ruptured popliteal cysts in RA to control synovitis. If resistant to nonsurgical treatment, cystectomy with further anterior synovectomy should be performed.
