Outcome of Thumb Reconstruction Using the First Dorsal Metacarpal Artery Island Flap

BACKGROUND Reconstruction of complex soft tissue defects of the thumb, with exposure of tendons, joints or bones, has always been a difficult task. We evaluated the functional and esthetic outcomes of 1st dorsal metacarpal artery island flap in reconstruction of post-traumatic soft tissue defects of the thumb. METHODS Between January 2012 and June 2014, fifteen patients with complex post-traumatic soft tissue thumb defects underwent 1st dorsal metacarpal artery island flap. Sensory function was evaluated with static 2-point discrimination and cortical reorientation. The mobility of the thumb was tested by the Kapandji score. The esthetic outcome was assessed. Patient's subjective satisfaction was evaluated by the visual analogue scale. RESULTS The mean flap size was 33.3x17.7 mm. All donor sites were grafted by full-thickness skin grafts from the groin. Fourteen flaps survived completely and one had distal flap necrosis was treated conservatively. The mean static two-point discrimination was 10.4 mm. Cortical reorientation was complete in 40%. The average Kapandji score was 7.1. The esthetic outcome was excellent in six, good in eight and poor in one subject. After a mean follow up period of 18.2 months, the mean subjective satisfaction score was 8.1; most patients regained all functions of the thumb and index finger and were pleased with the cosmetic appearance of the flap and donor site. CONCLUSION First dorsal metacarpal artery flap offers a sensate, pliable and versatile coverage for small to moderate sized thumb defects. Moreover, it provides good functional and esthetic outcomes with minimal donor site morbidity.