[Clinical effect of anterolateral thigh flow-through chimeric perforator free flap transplantation in the treatment of upper limb complex tissue defects with main artery injury].

Objective: To investigate the clinical effect of anterolateral thigh flow-through chimeric perforator free flap transplantation in the treatment of upper limb complex tissue defects with main artery injury. Methods: The study was a retrospective observational study. From May 2019 to January 2022, 11 patients with upper limb complex tissue defects combined with main artery injury who met the inclusion criteria were admitted to the Department of Hand, Foot and Ankle Surgery of General Hospital of Ningxia Medical University, including 7 males and 4 females, aged from 18 to 56 years. After debridement, the area of skin and soft tissue defects was from 20 cm×6 cm to 32 cm×10 cm, and the exposed area of dead cavity or deep tissue was from 7 cm×4 cm to 10 cm×7 cm. Three patients had radial artery defects with a length of 4 to 7 cm; two patients had ulnar artery defects with a length of 5 to 8 cm; 4 patients had defects in both ulnar and radial arteries with a length of 3 to 7 cm; and in two patients, the ulnar, radial and brachial arteries were all defective with a length of 4 to 8 cm. The anterolateral thigh flow-through chimeric perforator flap was designed and cut. The skin flap area was from 22 cm×7 cm to 32 cm×11 cm, the chimeric muscle flap area was from 7 cm×4 cm to 10 cm×7 cm, and the length of the flow-through vessel in the "T" shaped vessel pedicle was from 4 to 8 cm. When transplanting the skin flap, the proximal end of the vascular pedicle was anastomosed with the proximal end of the recipient site, and the distal end of the vascular pedicle was anastomosed with the more normal blood vessel at the distal end of the forearm; the invalid cavity was filled with the muscle flap. The donor site wounds of tissue flap were closed directly or treated with skin grafting. After operation, the blood supply and survival of the flap, the survival of the distal limb, and the survival of the skin graft at the flap donor site were observed. Computed tomography angiography (CTA) was performed to observe the patency of the proximal and distal anastomotic arteries from 2 to 4 weeks after surgery. During follow-up, the texture of the flap, the survival of the grafted skin and the healing of the donor area were observed. Results: One patient (complete forearm disconnection) developed distal limb blood disorder on 5 days after surgery. CTA examination suggested embolization of the distal anastomosis of the flow-through artery. more muscle and skin and soft tissue necrosis of the distal limb showed in emergency exploration. So, amputation was performed ultimately. No vascular crisis occurred in the skin flaps of the remaining 10 patients, and all skin flaps, distal limbs and the skin grafts in flap donor sites survived well. Two to 4 weeks after surgery, the proximal and distal ends of the anastomosed arteries were good in the patency. Follow-up for 11-37 months, the flap texture was good, and all donor site wounds healed well. Conclusions: The use of anterolateral thigh flow-through chimeric perforator flap to repair upper limb complex tissue defects accompanied by main artery injury can improve the success rate of limb salvage, which can be promoted in clinical practice.