The Role of Inconstant Perforating Arteries in Harvesting Radial Flaps

Abstract

Sir: We read with great interest the article by Saint-Cyr et al.1 regarding cutaneous perforators of the radial artery. In that study, a cadaveric dissection was performed to determine the size, location, and cutaneous territory of perforators originating from the radial artery. Knowledge of these perforators allows the surgeon to perform distally based radial artery flaps, avoiding sacrifice of the radial artery. Nevertheless, in rare cases, the same result can be achieved using inconstant perforators arising from vessels other than the radial artery. We recently treated a 45-year-old man affected by traumatic injury of the dorsal aspect of the right hand for whom a radial flap was proposed. Doppler examination and the Allen test were used to assess functional radial-ulnar anastomoses. The first incision was made at the ulnar side over the flexor carpi ulnaris, and the dissection began from the same side toward the radial artery. During the dissection, an unexpected perforator artery was found. The vessel measured 0.8 cm in diameter and was accompanied by two venae comitantes. After accurate and gentle dissection, the artery was demonstrated to originate from the superficial palmar arch and measured 4.6 cm in length. The radial artery was not vestigial and had a regular caliber (Fig. 1). A superficial vein was isolated and preserved up to 2 cm proximally, to obtain additional microvascular venous drainage (Fig. 2). The arterial branches originating from the radial artery were sectioned and the flap was harvested. After positioning the flap on the recipient site, microanastomosis between the superficial vein of the flap and the dorsal venous network was performed. The postoperative period was uneventful.Fig. 1.: A 12 × 5-cm skin paddle is drawn in the middle third of the dorsal aspect of the right forearm. The first incision was made at the ulnar side over the flexor carpi ulnaris, and the dissection began from the same side toward the radial artery. During the dissection, an unexpected perforating artery with two venae comitantes was found, originating from the superficial palmar arch. The artery measured 0.8 cm in diameter, whereas the whole pedicle measured 1.5 cm in diameter. The radial artery was not vestigial and had a regular caliber.Fig. 2.: The flap is centered on the perforating vessel. On the proximal edge of the flap, a superficial vein is isolated and preserved up to 2 cm proximally to obtain additional venous flap drainage. The arterial branches originating from the radial artery are sectioned. A 5-cm skin incision is performed to allow tunnelization of the flap.In our opinion, the surgeon should always take into account the eventuality of inconstant vessels,2 such as perforating arteries, median arteries, or ulnar superficial arteries. These vessels could not always be detected by arteriography and are invisible on Doppler examination. In our case, a nonvestigial radial artery was found and a perforating vessel arising from the palmar arch was used in harvesting the radial flap. Great support to the surgeon's work is given by imaging. Computed tomographic angiography is considered the standard preoperative study and should be systematically used. We believe that exact knowledge of the vascularization of the patient's forearm, provided by computed tomographic angiography, is strictly necessary for the surgical planning of the flap, revealing perforators originating from the radial arteries and inconstant perforator vessels. Nevertheless, the intraoperative finding of inconstant pedicles originating from perforators other than those arising from the radial artery should motivate the surgeon to find new reconstructive solutions. From this perspective, we conclude that dissection for a radial flap should be preceded by computed tomographic angiography and performed with surgical loupes, starting at the ulnar side toward the radial artery. Forearm anatomy is often unpredictable and the surgeon should consider moment by moment all the reconstructive chances to avoid sacrifice of the radial artery. Therefore, great attention should be paid to every perforator encountered because it could bring new reconstructive scenarios. DISCLOSURE The authors have no financial interest to declare. Luca Vaienti, M.D. Riccardo Gazzola, M.D. Giovanni Palitta, M.D. Dipartimento di Scienze Medico Chirurgiche Università Degli Studi di Milano IRCCS Policlinico San Donato Milan, Italy Enrico Vaienti, M.D. Università Degli Studi di Parma Parma, Italy