Correction of Triphalangeal Thumb with Small Delta Phalanx by Closed Wedge Osteotomy of the Proximal Phalanx: A Case Report

Background: Triphalangeal thumb (TPT) is a rare congenital anomaly, especially in the Asian population. Traditional treatments depend on the type of deformity and the presence of concomitant anomalies and include either excision in addition to the ligament reconstruction or fusion and shortening osteotomy. Instability and stiffness are the major concerns following the traditional techniques. Case Report: In this study, we report a case of right TPT with a small delta phalanx in a nine-year-old boy who was treated by proximal phalanx radial closed wedge osteotomy without delta phalanx resection or intracapsular dissection. The angular deformity and the appearance of the thumb were corrected by this simple procedure without resulting in instability and stiffness in the interphalangeal joint. Conclusion: Proximal phalanx closed wedge osteotomy is a rapid, simple, and effective technique with a low risk of unexpected complications for correcting the appearance in the cases of TPT with a small delta phalanx.