Exploration of the vascular angiosome of the extended lateral arm free flap: A cohort study in cadavers

The lateral arm flap is a highly reliable and versatile fasciocutaneous flap for extremity reconstruction. The flap can be harvested in an extended fashion to include the thin skin of the proximal forearm. In the extended version, the maximum amount of skin that can be harvested from the forearm remains unknown. We performed a cohort fresh frozen cadaver dye injection study to investigate this question. A total of seventeen cadaver flap dissections were performed. Our primary goal was to capture the complete angiosome of the extended lateral arm flap, including length and width. Our secondary goal was to explore how much of the flap can be safely harvested distally, past the lateral epicondyle. The overall mean area of dye staining was 23.48±4.60 cm², which represents the angiosome of the flap. The dye traveled an average of 3.60±4.94 cm into the forearm, past the lateral epicondyle, which suggests a “safe” zone for distal flap harvest. In conclusion, the extended lateral arm flap is a versatile option for extremity reconstruction and can be safely harvested distal to the lateral epicondyle. There is likely a limit, however, to how far distally the skin paddle can extend, which can be explored in future research.