Free Radial Forearm "Bunting" Flap for Reconstructing Soft-tissue Defects Involving Multiple Fingers.

SUMMARY: Reconstruction of soft-tissue defects on multiple fingers is challenging because the number of recipient vessels for free flaps is limited. We report the use of a free radial forearm flap with multiple perforator-based skin islands for the reconstruction of complex soft-tissue defects involving multiple fingers. The injuries were caused by a heat press. The flap was transferred, like "bunting," to the injured hand with an exteriorized pedicle. The technique presented here is advantageous because it simultaneously covers multiple defects and allows immediate hand therapy after the operation.

CASE

A 35-year-old, right-handed woman suffered a heat-press injury to the dorsum of her right digits. Eight days after the injury, surgery was performed under general anesthesia. After debridement of the necrotic tissue, all interphalangeal joints and proximal interphalangeal joints were exposed (Fig. 1). To cover the defects, a 4.5 × 17 cm free radial forearm flap was elevated from her left forearm. The donor site was covered with a full-thickness skin graft. The skin component of the flap was separated into 3 skin islands based on the clustered perforators (Fig. 2). The radial artery and accompanying vein in the flap were anastomosed end-to-end to the right radial artery and accompanying vein at the “snuff box,” respectively. The vascular pedicle was exteriorized (Fig. 3) and covered with artificial dermis (Pelnac, Gunze, Osaka, Japan).

Fig. 1.

After debridement of the necrotic tissue, all interphalangeal joints and proximal interphalangeal joints were exposed.

Fig. 2.

The skin component of the flap was separated into 3 skin islands based on the clustered perforators. Blue lines indicate the incision lines.

Fig. 3.

The flap was transferred to the defects like “bunting” with an exteriorized pedicle.

Hand therapy was started on the day after the operation. On postoperative day 21, the thumb, index, and middle fingers were separated and the pedicle was ligated. On postoperative day 35, the middle, ring, and little fingers were separated under local anesthesia. After 2 revisional surgeries for flap debulking, a good cosmetic result was obtained (Fig. 4).

Fig. 4.

After revisional surgeries, good cosmetic results were achieved.

DISCUSSION

Reconstruction of complex, soft-tissue defects involving multiple fingers is challenging for reconstructive surgeons. Pedicled, distant flaps are easy to use, but immobilization results in a functional loss for the patient. Therefore, if possible, a free tissue transfer is the best option for reconstruction of these types of soft-tissue defects.[1] However, in the case of complex defects involving multiple fingers, covering each defect with each free flap is difficult because of the limited number of recipient vessels.

To simultaneously reconstruct complex defects on multiple fingers using 1 free flap, the fingers should be bridged with a long and narrow, preferably axially patterned flap. Therefore, free fascial flaps, such as temporoparietal flaps,[2] serratus anterior fascial flaps,[3,4] and radial forearm fascial flaps,[5] are useful options for reconstruction because of their thinness and pliability.[6] However, the requirement of skin grafts over the flaps is a disadvantage of free fascial flaps. Coverage of the flap surface with a skin graft prevents the monitoring of capillary refill from the flap, resulting in late detection of any vascular occlusion. Moreover, because postoperative immobilization for 2–3 weeks is crucial for appropriate flap and graft incorporation,[6] effective hand therapy is delayed. By contrast, free flaps with multiple skin islands allow capillary refill monitoring from the flaps and enable immediate hand therapy, resulting in the avoidance of flap loss and achievement of better function.

In the present case, the soft-tissue defects ranged over all of the digits, requiring a long, narrow flap to cover the defects. A free forearm flap is one of the longest flaps with an axial vascular pedicle. Several perforators sprout from the radial artery and vein[7,8]; this allows the separation of the flap into 3 skin islands, like “bunting.”

Because the patient presented here was 150 cm tall and the length of the flap was slightly short for covering the defects, we exteriorized the pedicle. The exteriorized pedicle enabled us to increase the length of the flap and simplified the setting of the flap. We covered the exteriorized pedicle with artificial dermis to prevent the pedicle from drying out. However, this technique resulted in a thick pedicle with hypergranulation; this prevented ligation of the pedicle at flap separation. In another case of the exteriorized pedicle, we confirmed that wet dressings with a petroleum jelly ointment were appropriate for covering the pedicle.

CONCLUSIONS

In conclusion, we successfully reconstructed complex soft-tissue defects involving multiple fingers by using a free radial forearm “bunting” flap. The flap, with multiple skin islands and an exteriorized pedicle, enabled us to cover all of the digit defects with a minimum of microanastomoses. Therefore, we consider the “bunting” flap a useful option for reconstruction of complex soft-tissue defects involving multiple fingers.