True symphalangism is a rare anomaly of the hand. It is seldom indicated for surgical treatment, because the function of the proximal interphalangeal ( PIP ) joint, which is usually involved, is generally compensated for by hyperflexion of the adjacent distal interphalangeal ( DIP ) joint. We report a case of true symphalangism in a five-year-old boy, whose PIP and DIP joints were both ankylosed. The PIP joint of the affected fin-ger was reconstructed via a free vascularized toe-joint transfer. In the final follow-up evaluation at 15 months after the operation, 30° active motion was observed in the PIP joint. Radiographs demonstrated successful bone union and the growth plate remained open. No osteoarthritic changes were observed. The boy and his parents were satisfied with the surgical outcome, although the functional result was fair in terms of the range of motion. Thus, free vascularized toe-joint transfer is an effective method for true symphalangism, especially when the PIP and DIP joints are both ankylosed. However, the timing of the operation should be considered carefully to ensure adequate postoperative rehabilitation.
