Paediatric Locked Middle Finger due to Synovial Osteochondromatosis: A Case Report.

Synovial osteochondromatosis is a relatively rare condition of the hand. We present a rare case of a locked finger in a paediatric patient with synovial osteochondromatosis, in which a tumourous lesion was continuous with the flexor tendon and trapped proximal to the A1 pulley. After resection of the tumour and synovium, no recurrence was observed over a 6-month follow-up period. Synovial osteochondromatosis in the hand or fingers can lead to swelling and limited range of motion; however, symptom progression is usually slow. Moreover, it is uncommon for an extra-articular tumour to cause a sudden onset of locking symptoms without prior warning signs. Comprehensive excision of the synovium is essential, and ongoing observation for recurrence is necessary during follow-up. Level of Evidence: Level V (Therapeutic).