Arthroscopic treatment of localized synovial chondromatosis of the posterior knee joint.

Synovial chondromatosis is an uncommon, benign neoplastic process typically affecting adult men and most commonly involving the knee, hip, and elbow joints. Intra-articular primary synovial chondromatosis in the knee joint may be localized or generalized. The symptoms associated with localized synovial chondromatosis may include diffuse pain, swelling, restricted motion, crepitus with symptoms of locking and giving way, and posteromedial tenderness mimicking medial meniscus tear. Diagnosis is usually established with magnetic resonance imaging (MRI) and confirmed by histological examination. To our knowledge, synovial chondromatosis of the knee joint in the posteromedial corner has not been reported in the literature.