Canopy Flap: A Specially Shaped Flap for the Repair of Complex Hand Defects.

Abstract

Traditional flap transplantation for complex hand defect repair faces challenges like insufficient blood supply and scar contracture. This study aimed to explore the clinical value of the "canopy flap" with three-dimensional shaping in such repairs. A retrospective analysis was conducted on 13 patients with irregular single wounds and complex tissue defects (accompanied by deep tissue exposure and nerve injury) treated with canopy flaps from June 2021 to March 2025. The technique included preoperative wound contour tracing, flap design based on a single perforator vessel, harvesting under tourniquet control, tension-dispersed transfer, microvascular anastomosis, and standardized postoperative management. Follow-up assessments used the British Medical Research Council sensory grading scale and hand function evaluation. Of the 13 flaps, 12 survived completely with primary healing; 1 developed postoperative venous crisis that was successfully salvaged. Follow-up showed flap appearance/texture similar to surrounding skin and no significant scar contracture. Sensory recovery reached S4 (4 cases), S3 (7 cases), and S2 (2 case). Approximately 70% of patients achieved excellent/good hand function, with all donor sites healing without functional impairment. The canopy flap has high survival rate, good three-dimensional conformability, and reduces complications. It achieves favorable sensory and functional recovery, providing a valuable option for complex hand defect repair.