Irreducible Volar Subluxation of the Distal Interphalangeal Joint: An Unrecognised Cause.

This report describes a rare case of irreducible closed volar subluxation of the distal interphalangeal (DIP) joint of the small finger following a sports injury. Closed reduction failed, leading to open surgery, which revealed ulnar condyle entrapment between a partially torn extensor tendon and volarly displaced oblique retinacular ligament (ORL). Flexing the proximal interphalangeal (PIP) joint to 90° while extending the DIP joint relaxed the ORL, enabling dorsal repositioning and successful reduction. Awareness of this mechanism may help hand surgeons achieve effective reduction. Level of Evidence: Level V (Therapeutic).