Brachymetacarpia: Bilateral and Symmetrical Shortening of the Three Ulnar Digits

This report presents a rare deformity of bilateral and symmetrical brachymetacarpia affecting the three ulnar metacarpals (third, fourth, and fifth) in both hands. The shortening created a visual illusion making the index finger appear longer than the middle finger; however, radiographic imaging confirmed that the index finger and thumb were within normal dimensions. The primary functional impairment was an inability to form a firm fist due to a disruption of the metacarpal arch between the index and middle fingers, causing difficulty in daily tasks such as gripping a pen. As an innovative surgical solution, shortening of the normal-length second metacarpal was proposed instead of the conventional approach of lengthening the three affected short metacarpals. This reduces the procedure from three interventions per hand to one, and from a two-stage to a single-stage operation, thereby enhancing patient tolerance, procedural simplicity, and success rates. The surgical plan also included shortening of the common extensor tendon of the index finger at the forearm level to improve functional balance.