Free innervated latissimus dorsi muscle flap for reconstruction of full-thickness abdominal wall defects

Full-thickness abdominal wall defects continue to be a challenge for the reconstructive surgeon. The most frequently used reconstructive techniques are transfer of a pedicled, local abdominal flap or a distant flap from the thigh region. The purpose of this paper is to present a new approach to full-thickness abdominal wall reconstruction using an innervated free latissimus dorsi musculocutaneous flap. Four patients with large full-thickness abdominal wall defects underwent reconstruction with a free innervated latissimus dorsi muscle flap. In two patients, staged abdominal wall reconstruction was performed. Primary closure was first obtained with a skin graft. During the subsequent definitive reconstruction (with an innervated free latissimus dorsi muscle flap), this skin graft was not excised. Instead, deep dermabrasion of the skin graft was performed, leaving a residual dermal layer. This layer was then covered with a free innervated latissimus dorsi muscle flap. In these two cases, there was no need for the use of a prosthetic mesh. A single stage reconstruction was performed in the other two cases. After abdominal wall sarcoma resection, Prolene mesh was placed and subsequently covered with a free innervated latissimus dorsi muscle flap. There were no free flap failures. The average time of surgery was 4 hours, 50 minutes. The average hospital stay was 14 days. No significant complications occurred except for one donor site seroma. No hernias have occurred postoperatively. The mean follow-up was 21 months. Postoperatively, electromyographic testing was performed regularly in all patients to document reinnervation of the latissimus dorsi muscle flap. With reinnervation and intensive muscle training, the transplanted latissimus dorsi muscle offers enough contractile capacity and strength to adequately replace the function of the missing abdominal wall muscles. In complicated staged reconstructions, dermabrasion of the temporary skin graft allows for the use of a residual dermal layer as a fascia-like substitute to aid in the restoration of structural integrity. The combination of the dermal layer with an innervated free latissimus dorsi muscle provides a strong, vascularized fascial repair as well as an overlying vascularized soft-tissue coverage. In conclusion, adequate functional dynamic reconstruction of full-thickness abdominal wall defects is possible using an innervated free latissimus dorsi muscle flap. The reinnervated latissimus dorsi muscle is suitable for reconstitution of the missing functional and anatomic components of complex abdominal wall defects.