[Clinical effects of free latissimus dorsi muscle flap harvested through small incision under the assistance of endoscopy in repairing deep wounds in limbs].

Objective: To investigate the clinical effects of free latissimus dorsi muscle flap harvested through small incision under the assistance of endoscopy in repairing deep wounds in limbs. Methods: This study was a retrospective observational study. From March 2015 to March 2024, 38 patients with deep wounds in limbs, who met the inclusion criteria, were admitted to Xijing Hospital of Air Force Medical University, including 26 males and 12 females, aged 19 to 64 years. The wounds were located in the lower leg in 21 cases, ankle in 9 cases, knee joint in 3 cases, and forearm in 5 cases. After debridement, the wound area required for muscle flap transplantation was 11.0 cm×9.0 cm to 28.0 cm×13.0 cm. The free latissimus dorsi muscle flaps were harvested through a small horizontal incision of 4-5 cm in length along the dermatoglyph in the armpit combined with a secondary incision of about 1 cm in length at the posterior axillary line under the assistance of endoscopy, with area of the muscle flap of 12.0 cm×10.0 cm to 29.0 cm×14.0 cm and length of vascular pedicle of 6-8 cm. The split-thickness skin grafts were harvested to cover the muscle flaps and the residual wounds. The harvesting time and the amount of blood loss during the harvesting process of the free latissimus dorsi muscle flap were recorded. The survivals of the transplanted muscle flap and skin graft, wound healing, and complications in the flap donor and recipient areas were observed after surgery. During follow-up, the appearance in the recipient area, the scar condition in the flap donor area, and the function of the upper limb on the flap donor side were observed. Results: The time for harvesting the free latissimus dorsi muscle flap was 160-200 minutes, with an average of 185 minutes. The amount of blood loss during the harvesting process of the muscle flap was 10-30 mL, with an average of 25 mL. Two patients developed complications in the recipient area after surgery. Among them, one patient experienced vascular crisis, the muscle flap recovered blood flow after emergency surgery to remove the thrombus and re-anastomosis of the vein, and ultimately the wound healed well; one patient had an infection at the edge of the muscle flap, and the wound healed after treatment such as debridement and dressing change. The transplanted muscle flaps and skin grafts completely survived in the remaining 36 patients. Two patients developed cystic effusion in the flap donor area about one week after surgery, and the flap donor area recovered well after puncture drainage and pressure bandaging treatment three weeks after surgery; the remaining patients had no complications such as incision infection or rupture in the flap donor area. Follow up for 6 to 18 months showed that the transplanted muscle flap and skin graft in the recipient area had good appearance, the scar in the donor area was concealed and mild, and the upper limb movement on the flap donor side was not restricted. Conclusions: Under the assistance of endoscopy, the free latissimus dorsi muscle flap can be harvested through a small horizontal incision along the dermatoglyph in the armpit, with small damage to the donor area, fast postoperative recovery, mild and concealed scar. It is in line with the goal of minimally invasive surgery and worthy of promotion and application.