Objective: To explore the feasibility and accuracy of modified three longitudinal and five transverse method in locating perforating branches before anterolateral thigh perforator flap (ALTP) repair.
Methods: Between January 2019 and December 2019, 41 patients with skin and soft tissue defects were repaired with ALTP. There were 31 males and 10 females. The age ranged from 18 to 61 years, with an average of 32 years. The soft tissue defects were caused by trauma in 38 cases, and the time from injury to operation was 3-7 days, with an average of 4 days. The wounds left after excision of scar contracture deformity because of burn in 3 cases. Soft tissue defects located at upper limbs in 16 cases and lower limbs in 25 cases. The size of soft tissue defects ranged from 10 cm×4 cm to 25 cm×12 cm. Before operation, zonesⅠ, Ⅱ, Ⅲ, and Ⅳwere formed on the anterolateral thigh by modified three longitudinal and five transverse method. The perforating branches were detected in these four zones by Doppler ultrasound, and the skin flaps were designed according to the wound area. The perforating branches were explored during operation, and the distribution and types of perforating branches in each zone and the relationship between perforating branches and lateral femoral cutaneous nerve were observed. The ALTP with the size of 12 cm×5 cm to 30 cm×10 cm was used to repair the wound, and the donor site was sutured directly or repaired with the flap.
Results: A total of 117 perforating branches were detected in 41 patients before operation, and 111 perforating branches were found during operation, with a false positive rate of 5%. The probability of perforating branches in zonesⅠ, Ⅱ, Ⅲ, and Ⅳ were 56%, 73%, 76%, and 66% respectively, and the false positive rates were -9%, 7%, 16%, and 4%, respectively. All perforating branches located near the trunk of lateral femoral cutaneous nerve, especially in posterolateral area. There were only 1 perforating branch in 6 cases, 2 perforating branches in 12 cases, 3 perforating branches in 10 cases, and 4 perforating branches in 13 cases. The main types of perforating branches in zonesⅠ, Ⅱ, Ⅲ, and Ⅳ were transverse perforating branches, oblique perforating branches, descending perforating branches, and descending perforating branches, respectively. Partial distal necrosis occurred in 2 cases and complete necrosis occurred in 1 case after operation, and the wounds were repaired with skin grafts. The remaining 38 flaps survived successfully, and the wounds and the incisions of donor sites healed by first intention. All patients were followed up 3 to 12 months, with an average of 6 months. The appearance and texture of the skin flap were acceptable, and linear scar remained in the donor site.
Conclusion: It can simply locate and distinguish the perforating branches and better protect the lateral femoral cutaneous nerve by using the modified three longitudinal and five transverse method before ALTP repair.
目的: 探讨股前外侧穿支皮瓣（anterolateral thigh perforator flap，ALTP）术前基于改良三纵五横法定位穿支的可行性及准确性。.
方法: 2019 年 1 月—12 月，采用 ALTP 修复 41 例皮肤软组织缺损。男 31 例，女 10 例；年龄 18～61 岁，平均 32 岁。外伤致软组织缺损 38 例，受伤至手术时间 3～7 d，平均 4 d；烧伤后瘢痕挛缩畸形切除术后创面 3 例。软组织缺损部位：上肢 16 例，下肢 25 例。软组织缺损范围 10 cm×4 cm～25 cm×12 cm。术前采用改良三纵五横法在股前外侧形成Ⅰ、Ⅱ、Ⅲ、Ⅳ区，用便携式多普勒超声在上述 4 个区域内探测穿支，并根据创面范围设计皮瓣；术中探查穿支，观察各区穿支分布、类型以及穿支与股外侧皮神经关系，计算穿支出现概率及假阳性率；最终切取大小为 12 cm×5 cm～30 cm×10 cm 的 ALTP 修复创面。供区直接缝合或皮瓣修复。.
结果: 术前探测 41 例患者共有穿支 117 条，术中探查发现 111 条穿支，假阳性率为 5%；Ⅰ、Ⅱ、Ⅲ、Ⅳ区穿支出现概率分别为 56%、73%、76%、66%，假阳性率分别为–9%、7%、16%、4%。所有穿支均位于股外侧皮神经主干附近，且以后外侧为主。4 个区域中共有 1 条穿支 6 例、2 条 12 例、3 条 10 例、4 条 13 例；Ⅰ、Ⅱ、Ⅲ、Ⅳ区穿支类型主要为横支穿支、斜支穿支、降支穿支、降支穿支。术后 2 例皮瓣发生远端部分坏死、1 例完全坏死，经植皮修复创面；其余 38 例皮瓣顺利成活，创面及供区切口均Ⅰ期愈合。患者术后均获随访，随访时间 3～12 个月，平均 6 个月。皮瓣外观、质地尚可，供区残留线状瘢痕。.
结论: ALTP 术前基于改良三纵五横法可简单定位穿支血管分布和走行，便于术中切取皮瓣时更好地保护股外侧皮神经。.
Keywords: Modified three longitudinal and five transverse method; anterolateral thigh perforator flap; lateral femoral circumflex artery; lateral femoral cutaneous nerve; perforating branch.