Surgical anatomy of the lateral supramalleolar flap in arteritic patients: an anatomic study of 24 amputation specimens.

The lateral supramalleolar flap (LSMF) is frequently used for covering major tissue defects of the foot and ankle but usually, in case of arteriopathy of the lower limbs, this device is contra-indicated. Twenty-four specimens of amputated limbs of patients suffering from arteriopathy of the lower limbs allowed us to study the vascular anatomy of this flap after intra-arterial injection of colored latex. At the time of the amputation the average age of the patients was 68.5 years. The clinical signs of arteriopathy had been present for 3-16 years. In 10 cases the amputation was performed directly, in 14 cases after an unsuccessful attempt at revascularization. The dissection results revealed certain specificities in the vascularization of the LSMF with arteriopathy. The perforating branch of the peroneal artery was found in all cases. The descending branch of this perforating artery was found to be patent in 22 cases but slim in five cases. It was absent in two cases. The superficial peroneal nerve and its vascular network always participated in the vascularization of the flap. Thus, its preservation in the distal part of the flap offers a second vascular flow to the pedicle of the LSMF. This specificity increases the theoretical feasibility of the LSMF from 17 to 22 cases out of 24 in our dissections. The authors suggest a theory according to which the evolution of arteriopathy and the gradual concomitant development of a supply network, which effects the vascularization of the sensory nerves too, induces the "anticipation" of a flap. The preliminary distal revascularization by bypass grafts or by some kind of endovascular treatment should guarantee the good vascularization of a limb and the reliable use of this neurocutaneous arterial network.