Abstract We report a case of an extremely rare form of a localized extra-articular synovial chondromatosis in a prepatellar bursa. Synovial chondromatosis (SC) is an uncommon and benign disease of the synovium characterized by formation of multiple loose bodies, most of which subsequently become calcified and/or ossified. The process typically affects large joints however an extra-articular variant has, rarely, been reported in bursae and tendon sheaths. To the best of our knowledge, this is the first report in the English language literature of extra-articular synovial chondromatosis in this location.