[Efficacy of free perforator flap combined with great toe transplantation in repairing thumb damage combined with thermal crush injuries in the hand].

<b>Objective:</b> To explore the efficacy of free perforator flap combined with great toe transplantation in repairing thumb damage combined with thermal crush injuries in the hand. <b>Methods:</b> This study was a retrospective observational study. From May 2014 to March 2024, seven cases (5 males and 2 females, aged from 25 to 46 years) with thumb injuries combined with thermal crush injuries in hands were admitted to the 988^th Hospital of Joint Logistics Support Force of the PLA. After surgical debridement, the thumb defects were classified as grade Ⅱ in 2 cases, grade Ⅲ in 3 cases, and grade Ⅳ in 2 cases. The great toe transplantations were adopted to reconstruct the damaged thumb, and subsequent measurements indicated that the wound area of the affected hand ranged from 9.0 cm×4.0 cm to 18.0 cm×10.0 cm. Hand wounds were repaired in 5 cases by free anterolateral thigh perforator flap transplantations and in 2 cases by free deep inferior epigastric artery perforator flap transplantations. The harvested perforator flap area ranged from 9.5 cm×4.5 cm to 19.0 cm×11.0 cm. The arteries of the perforator flap and transplanted great toe were anastomosed to the radial artery of the affected hand, while the veins were anastomosed to the radial vein, cephalic vein, or other matching veins in the recipient area. Meanwhile, the cutaneous nerves carried by the perforator flap were anastomosed with the superficial branch of the radial nerve or the palmar cutaneous branch of the median nerve in the recipient region. The wounds in the flap donor sites were closured by suture or repaired by skin grafting. After the surgery, the survival status of the reconstructed thumb and the perforator flap were observed, as well as the healing conditions at the donor and recipient sites. During the postoperative follow-up, the bone healing condition of the reconstructed thumb was examined, and the appearance and function of the reconstructed thumb were observed. The appearance of the perforator flap was observed, the two-point discrimination distances and sensory recovery were detected. The function of the foot after the removal of the great toe was also observed. At the last follow-up, the functions of the reconstructed thumbs of patients were evaluated with reference to the trial standard for the evaluation of thumb and finger reconstruction function formulated by the Hand Surgery Society of the Chinese Medical Association. <b>Results:</b> Both the reconstructed thumb and the perforator flaps survived after the operation. The sutured sites of the perforator flaps in 2 cases had delayed healing due to fat liquefaction and skin edge inflammation. The wounds of the recipient areas of the remaining cases healed well. All the wounds of the donor areas healed well. During the follow-up period of 8 to 18 months, the bone of the reconstructed thumb healed well, with its appearance being similar to that of the healthy side. The opposition and apposition functions of the reconstructed thumb were satisfactory, adequately meeting the demands of daily life and work. The appearance of the perforator flap was good, the two-point discrimination distance was 0.7-1.6 cm, and the sensation recovered well. The walking and standing functions of the foot were normal after the removal of the great toe. At the last follow-up, the functional evaluation results of the reconstructed thumbs of all patients were as follows: excellent in 3 cases, good in 3 cases, and fair in 1 case. <b>Conclusions:</b> The free perforator flap in combination with the great toe transplantation is an ideal method for treating thumb damage combined with thermal crush injuries in the hand. It has the advantages of repairing complex wounds in the hand while completing thumb reconstruction, and restoring the hand function to the maximum extent.