“Revisiting the Reverse Sural Artery Flap: Anatomic Study and Novel Modifications for Extended Flap Reach”

Background: The Reverse Sural Artery Flap (RSAF) supplied by distal peroneal perforators is a versatile local flap option for distal limb coverage. We describe perforator distribution in cadaveric dissections, and our clinical experience with four novel modifications (perforator skeletonization, Achilles tendon release, tunneling under the Achilles tendon, proximal peroneal artery ligation) to allow greater reach for the RSAF. Methods: 38 cadaveric legs were dissected to study the peroneal perforators. 12 patients from 5-73 years-old underwent RSAF and the proposed modifications for a variety of defects, including the medial foot and distal forefoot. Results: From the cadaveric study, terminal peroneal perforator was at a mean distance of 10.96±3.67 cm above the malleolus. Only 10.6% of distal-most perforators were within the last 20% of the fibular length, or 6.76 cm from the malleolus. Clinical series findings were comparable, with adult distances of 9.31±1.80 cm. However, the pivot point was lower, at 6.67±1.59 cm, owing to perforator skeletonization and dissection off the Achilles in all cases, tunneling under the Achilles in four, and proximal peroneal artery ligation in one. Two had subsequent <10% distal tip necrosis and one 50% superficial epidermolysis, which healed with local care. Conclusions: The terminal peroneal perforator may lie higher than the 5 cm pivot point generally recommended for the RSAF. For these cases, perforator skeletonization, dissection off and/or tunneling under the Achilles tendon, and even proximal peroneal artery ligation can allow further reach of the RSAF to reliably cover distal defects including the medial foot and forefoot.