Abstract
We report a case of medial plica syndrome with unique features. The patient was a 53 year old woman with severe knee pain. On the basis of physical examinations, medial plica syndrome was suspected, caused by a tumor-like mass in the plica synovialis. Impingement of the mass in the patellofemoral joint was evident. MRI showed a smooth, distinct region with a diameter of 3 cm in the plica synovialis. We performed arthroscopic extirpation of the inflammatory synovium and ruptured plica including the tumor-like mass. The pathological diagnosis was a mixture of acute and chronic synovitis. All the symptoms were disappeared immediately after surgery. Some cases of intraarticular soft tissue tumors causing mechanical symptoms in the knee joint have been reported previously. Mechanical impingement of tumor-like tissues or synovial masses should be considered in the differential diagnosis of knee pain.
