The First Dorsal Metacarpal Artery Perforator Free Flap: The Comet Flap

Background: Distal extremity defects pose a particular challenge to the reconstructive surgeon; however, advances in perforator flaps have expanded the potential reconstructive options. In this article, the authors present their experience in reconstructing distal extremity defects using a thin, cutaneous free flap based on the perforator of the first dorsal metacarpal artery: the comet flap. Methods: A retrospective review was performed on all patients who presented with a distal extremity defect and underwent reconstruction using a comet flap between 2015 and 2019. Patient demographics, flap anatomy and harvest, and postoperative course were reviewed and analyzed. Results: A total of 16 patients were included. The mean patient age was 36.5 years. Trauma was the most common cause. The average defect size was 5.4 × 3.2 cm. The average pedicle length of the comet flap ranged from 3.5 to 30 cm, depending on involvement of the radial vessels. All donor sites underwent uncomplicated closure with local rhomboid flaps. One flap was complicated by an acute venous thrombosis that was successfully treated operatively. The flap survival rate was 95 percent. All patients were able to maintain their preoperative range of motion and were satisfied with their final outcome. Follow-up time ranged from 6 to 50 months. Conclusions: Local flaps remain an important reconstructive approach for distal extremity defects; however, in complex soft-tissue injuries, free tissue transfers become necessary. The comet flap is a safe, versatile, and reliable flap for reconstructing upper and lower extremity defects that can be performed in a single procedure under regional anesthesia. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.