Use of a Bilobed Second Dorsal Metacarpal Artery-Based Island Flap for Thumb Replantation

PurposeAn extensive traumatic defect at the level of the proximal phalanx of the thumb presents difficulty in replantation. We report bilobed second dorsal metacarpal artery–based island flap harvested from both the index and middle fingers for reconstruction of the defect and preservation of the normal thumb length.MethodsFrom March 2004 to October 2008, 15 patients (11 men and 4 women; mean age, 35 y; range, 18 to 55 y) with completely or incompletely amputated thumbs associated with extensive defects in the proximal phalanx had replantation and reconstruction. In all cases, a bilobed second dorsal metacarpal artery–based island flap was used due to the large size of the defect. After flap transfer, anastomoses between the veins of the distal part of the thumb and the flap were performed. At the final follow-up, we assessed the mean active range of motion of the metacarpophalangeal and interphalangeal joints of the thumb and the span of the first web in the thumbs that survived. Active motion of the donor fingers was also assessed.ResultsIn this series, 13 thumbs survived and 2 failed. All flaps survived completely. At the mean follow-up of 27 months (range, 24 to 29 mo), the mean active motion arcs of metacarpophalangeal and interphalangeal joints were 32° (range, 15° to 45°) and 31° (range, 0° to 47°), respectively. Full active range of motion was observed in all patients in both the metacarpophalangeal and the proximal interphalangeal joints of the donor index and middle fingers.ConclusionsBilobed second dorsal metacarpal artery–based island flap transfer is a useful and reliable technique for thumb replantation when there is an extensive defect in the proximal phalanx and when a single-digit dorsal metacarpal artery island flap is too small.Type of study/level of evidenceTherapeutic IV.