Redefining the Vascular Classifications of the Lateral Supramalleolar Flap.

BACKGROUND:The blood supply of the lateral supramalleolar flap (LSMF) generally comes from the perforating branch of the peroneal artery. However, the cutaneous branch may also receive blood from the anterior tibial artery. The main objective of the present study was to clarify the vascular anatomy of the LSMF. METHODS:Anatomical dissections were performed on 28 perfused fresh cadaver legs. The cutaneous branches of LSMF were identified, and the anatomic relationship between the cutaneous branches and the peroneal and anterior tibial arteries was analyzed. RESULTS:The vascular supply for LSMF was divided into 2 main types. A collateral inferolateral branch from the anterior tibial artery anastomosed with the perforating branch of the peroneal artery around the inferior tibiofibular angle, and the main cutaneous branch of the flap arose from this arterial anastomosis in 20 of 28 limbs (71.4%). The collateral inferolateral branch was absent or very small in the other 8 of 28 dissections (28.6%), and the cutaneous branches solely arose from the perforating branch of the peroneal artery. The anastomosis of the descending branch of the peroneal artery and anterior lateral malleolar artery was always (100%) found around the tibiotalar joint. CONCLUSIONS:In addition to the perforating branch of the peroneal artery, the LSMF may also receive blood from the anterior tibial artery through the collateral inferolateral branch. New modified proximally based flaps could be designed, and caution is warranted for these variations when a distally based flap is performed.