True Symphalangism of All Bilateral Proximal Interphalangeal Joints with Multi-carpal Coalition and Hypoplasia of the Ulnar Styloid Process

Abstract

Symphalangism is a rare genetic condition characterized by ankylosis of the proximal interphalangeal (PIP) or/and distal interphalangeal (DIP) joints. The patient presented with fused bilateral PIP joints and poor flexion, and an unsatisfactory range of motion (ROM) in the metacarpophalangeal (MP) and DIP joints. Concomitantly, multi-carpal coalition, proximal carpal malalignment, and ulnar styloid process abnormality were also observed in radiographs obtained at diagnosis. Rehabilitation training of the MP and DIP joints and a wrist supporter were recommended to achieve MP and DIP functional motion and restrict dramatic wrist motion. This is the first case report of symphalangism with multi-carpal coalition and abnormality of the ulnar styloid process to the best of our knowledge.