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A double patella-like condition secondary to synovial osteochondromatosis

Yoshiteru Kajikawa*, Yuji Arai, Hisatake Takamiya, Tetsuo Higuchi, Gen Mori, Shinsuke Morisaki and Toshikazu Kubo

Author Affiliations

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan

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Sports Medicine, Arthroscopy, Rehabilitation, Therapy & Technology 2012, 4:31  doi:10.1186/1758-2555-4-31

Published: 3 September 2012


To our knowledge, this is the first case of synovial osteochondromatosis in a patient presenting with a double patella-like condition. The true duplication of the patella, which is called double patella, is extremely rare. In our case, the operative and histopathological findings showed that the double patella-like condition was secondarily induced by synovial osteochondromatosis. Synovial osteochondromatosis should be considered as a differential diagnosis for congenital double patella.

Osteochondromatosis; Synovial osteochondromatosis; Chondromatosis; Double patella; Knee