Reverse saphenous conduit flap in the dog

Abstract

SUMMARY Reverse saphenous conduit flaps, with pedicles incorporating the cranial and caudal branches of the saphenous artery and affiliated veins, were raised and transplanted to skin defects over the dorsal, medial, or plantar metatarsal surface in 15 dogs. The resultant flaps had a 100% survival rate, whereas control flaps, with the saphenous vessels divided, developed various degrees of necrosis. Fluorescein dye (1 g) was administered iv after the completion of each procedure, to assess flap circulation. Of 15 reverse saphenous conduit flaps viewed with an ultraviolet light source, 13 had brighter fluorescent patterns of the distal half of the flap, compared with the control flaps. The finding of false-negative and false-positive fluorescent patterns in this study suggested that discretion is required when trying to correlate results of fluorescein dye studies with flap circulation and viability. The reverse saphenous conduit flap is a flap that may have special application for large skin defects at or below the tarsus and that enables the surgeon to close the recipient bed without resorting to more expensive or time-consuming procedures. However, presurgical angiographic evaluation of the saphenous vasculature may be advisable to assure that the reverse saphenous conduit flap can be used safely when lower limb reconstruction is required after major trauma. The saphenous artery is not a direct cutaneous artery, but a vascular “conduit” that supplies small direct cutaneous articles to the overlying skin. The flap developed in this study is termed a “reverse saphenous conduit flap” to distinguish it from the related axial pattern flap and to account for the reversal of blood flow in the saphenous vasculature.