A novel technique to reduce donor site morbidity after radial forearm free flap (RFFF) harvest, using a local full-thickness skin graft (FTSG), is described. Thirty consecutive patients undergoing RFFF for head and neck reconstruction were enrolled in a prospective study. Donor site defect closure was performed with spindle-shaped FTSGs excised from the wavelike skin incision made for the vascular pedicle. Both the removal site of the FTSG on the volar forearm and the covered RFFF donor site healed uneventfully in 29 cases, with no impairment of function related to the skin graft. No skin graft failure and no exposure, tenting, or adherence of the flexor tendons occurred. All patients expressed satisfaction with postoperative pain, the functional outcome, and cosmetic appearance. Primary donor site defect closure could be achieved in all cases with the use of a local FTSG. This graft can be gained at the access incision for the vascular pedicle, avoids expansion of the incision for a local flap technique, and does not prolong wound healing, and thus reduces both donor site and graft site morbidity of the RFFF. This technique leads to an inconspicuous aesthetic result with no apparent relevant functional deficits and avoids the need for a second donor site.
Reconstructive procedures after ablative head and neck cancer surgery often require the replacement of tissue by transplantation of microvascular anastomosed free flaps in order to compensate functionally and aesthetically for the defect. For soft tissue reconstruction of limited-size defects, the radial forearm free flap (RFFF) has become the most commonly used flap in the head and neck region. This thin and versatile flap is also used widely for thin defects of the oral cavity, with good functional and cosmetic results. The high calibre of the vessels and the long vascular pedicle considerably facilitate anastomoses and make the RFFF a reliable flap with a high success rate.
The harvesting of a defined amount of tissue for the reconstruction of remote defects inevitably leads to a removal defect at the donor site, which is potentially accompanied by corresponding morbidity. Prolonged wound healing, for example, is an undesirable inconvenience that may lead to poor aesthetic results, and flexor tendon exposure may lead to an appreciable loss of function. Since the introduction of the RFFF more than 30 years ago, different approaches have been made to reduce donor site morbidity. These range from changes in the design of the flap, for example the suprafascial dissection, to different closure techniques. Oversewing with the flexor muscles has been recommended to protect the flexor carpi radialis tendon, and the approximation of the flexor digitorum muscle to the flexor and abductor pollicis longus muscle has been described to provide a well-vascularized bed for a split-thickness skin graft. The split-thickness skin graft requires a further donor site and is prone to inconvenient prolonged wound healing. In order to avoid its use, different methods of primary closure have been reported: the V–Y transposition of an ulnar forearm fasciocutaneous flap, a transposition flap, the prefabrication of the forearm fascia, and the use of tissue expanders.
For indirect defect closure, autogenous full-thickness skin grafts (FTSG) have been reported to achieve similar or better aesthetic results. These can be gained locally or harvested from remote regions such as the inner upper arm, abdominal wall, or groin.
For the sake of completeness, allogeneic grafts and vacuum-assisted closure (sub-atmospheric pressure dressing) should also be mentioned here, however these have taken a back seat in the face of the good results obtained and feasibility of the previously described procedures.
In head and neck microvascular reconstruction, a long pedicle and a thin flap are often needed, which commonly leads to the removal of the RFFF from the very distal forearm. The resulting donor site defect is close to the hand wrist, requiring special consideration with regard to wound closure due to the superficial flexor tendons and the restricted amount and moveability of the local tissue.
Materials and methods
This study was approved by the local ethics committee. All patients gave written informed consent after being provided with detailed information of the procedure. Thirty consecutive adult patients undergoing RFFF reconstruction for orofacial defects were included in this prospective study. A detailed history was taken regarding general diseases, former operations or trauma, risk factors, diseases of haemostasis, and smoking and alcohol consumption. Evaluations were performed pre-, intra-, and postoperatively. The preoperative assessment included age, gender, donor arm (dominant or non-dominant), and an Allen’s test. During the intraoperative assessment, the dimensions of the skin paddle as well as any operative difficulties or complications were noted.
The duration of graft healing was defined as the time taken until a dry dressing was sufficient.
Thirty patients with 30 RFFF were included in this study (13 female and 17 male). Twenty-five RFFF were harvested from the left arm and five from the right arm. The mean age of the patients was 61.2 years, ranging from 20 to 90 years. All 30 patients were available for a follow-up examination at 3 months postoperatively.
All flaps were raised as a fasciocutaneous RFFF, without the use of a tourniquet. For aesthetic reasons, no flap was extended to the dorsal aspect of the arm. The superficial branch of the radial nerve was identified over the paratenon of the brachioradialis muscle and was carefully preserved during further dissection in all cases to prevent paresthesia of the back of the hand between the thumb and index finger. No coverage of the flexor tendons by oversewing muscle bellies of the flexor muscles was performed. The radial artery was not reconstructed in any patient.
A wavelike skin incision for exposure of the proximal vascular pedicle was used in all cases as a prerequisite for the introduced technique ( Fig. 1 ). Before making a skin incision, the dimension of the sinusoidal curve was planned in relation to the future donor site defect such that the length of the curve matched the oblique distance and its width matched half of the oblique distance of the defect. Two spindle-shaped FTSGs out of the convexity of the incision line were taken from the adjacent skin of the volar forearm (see Fig. 2 ). Prior to excision, the widths of the biconvex FTSGs were determined as half the width of the defect site. Temporary parallel mattress sutures for preserving the defect size were performed until the FTSGs were finally sutured in place. After a slight rotation from their original longitudinal orientation, the two spindle-shaped FTSGs were used to cover the donor site defect of the RFFF. This rotation to an oblique to perpendicular orientation of the FTSGs was performed to avoid parallel arrangement to the flexor tendons. No fenestrating incisions or cross-sutures for size reduction of the wound were performed. To prevent formation of seroma, a tie-over dressing was used for 10 days.
In all cases the donor site of the local FTSG was closed primarily in the context of the closure of the access incision (see Fig. 3 ). To accomplish this, gentle subcutaneous mobilization was performed. A passive silicone capillary drain was placed subfascially before closure. No vacuum-assisted closure (sub-atmospheric pressure dressing) or splint cast was used.
The local FTSG was feasible in all 30 cases. Both the FTSG removal site on the volar forearm and the subsequently covered donor site of the RFFF healed uneventfully in 29 cases. The mean duration of wound healing to complete recovery was 12 ± 2.4 days; the mean defect size was 25 ± 8.4 cm 2 .
The local FTSG resulted in robust wound coverage, with no later wound breakdown. No second donor site was necessary. No skin graft failure and no exposure, tenting, or adherence of flexor tendons occurred. No sensory disturbance of the back of the hand between the thumb and index finger regarding the superficial radial nerve was reported by any patient. No patient complained of a feeling of tension in the forearm. No patient reported cold intolerance or complained of a poor aesthetic result. For functional and aesthetic results at 3 months after the operation, see Figs. 4–7 . In none of the cases did compartment syndrome occur. One patient had postoperative seroma underneath the skin graft that occurred 15 days after surgery; there was no impairment of the skin transplant.