[Effect of accurately localized mini anterolateral thigh perforator flap in repairing medium-sized skin and soft tissue defects in fingers].

Objective: To explore the effect of accurately localized mini anterolateral thigh perforator flap in repairing medium-sized skin and soft tissue defects in fingers. Methods: The study was a retrospective observational study. From December 2019 to September 2022, 15 patients with medium-sized skin and soft tissue defects who met the inclusion criteria in fingers were admitted to the Second Affiliated Hospital of Wenzhou Medical University, including 12 males and 3 females, aged 23 to 62 years. After debridement, the wounds were all accompanied by exposed tendons, bones, vessels and nerves, with an area from 4.0 cm×3.0 cm to 8.0 cm×3.5 cm. Computed tomography angiography and color Doppler ultrasonography examinations were performed on both lower limbs of the patient before surgery to accurately locate the anterolateral thigh perforators. When the flap with area from 6.0 cm×3.0 cm to 11.0 cm×4.0 cm was harvested, the flap was thinned. The artery and vein perforators of the flap were anastomosed respectively with the digital artery and dorsal metacarpal vein. If there was avulsion injury, infection, or burn in the recipient area, the main arterial and veinous vessels carried by the skin flap was anastomosed with the radial artery and accompanying vein. The lateral thigh cutaneous nerve carried by the flap was anastomosed with the stump of the digital nerve. The types of perforators of the lateral thigh artery were observed during operation and compared with the location of the vessels before operation. After operation, the survival and adverse complication of the flap were closely observed. During follow-up, the skin flap color, texture, and shape were observed; the wound healing in donor area was observed. At the last follow-up, the two-point discriminative distance of the affected finger pulp was measured, and the function of the affected finger was evaluated using the trial standard for the evaluation of functions of upper limbs of Hand Surgery Society of Chinese Medical Association, and the interphalangeal joint movement of the affected finger was observed; the patients' complaints about the adverse effects of flap resection on lower limbs were recorded. Results: During the operation, it was observed that the perforators of the flaps in 11 patients were the descending branch of the lateral circumflex thigh artery, in two patients, the perforators of skin flaps were the oblique branch of the lateral thigh artery, and the perforators in another two patients were the transverse branch of the lateral circumflex thigh artery, which were consistent with the preoperative vascular localization. After operation, all flaps survived without vascular crisis and infection. The patients were followed up for 6-12 months, the flaps had excellent color, texture, and appearance; only linear scars remained on the donor wound. At the last follow-up, the two-point discrimination distance in the finger pulp was 7-11 mm; the affected finger function was rated as excellent in 6 cases, good in 6 cases, and fair in 3 cases; the flexion and extension function of the finger was not affected; two patients complained of numbness in the lateral thigh after excision of the skin flap, and the other 13 patients had no complain of adverse complaints. Conclusions: The perforating branch in lateral thigh region can be accurately located by computed tomography angiography and color Doppler ultrasonography, accurate positioning of perforators before operation can reduce the damage to the donor area during the incision of the flap, the appearance and function of the affected finger can be restored to the maximum extent by thinning the transplanted flap and rebuilding the finger sensation. Therefore, it is an effective and reliable way to repair the medium-sized skin and soft tissue defects of fingers with the mini thigh anterolateral perforator flap.