目的  介绍腓肠肌外侧头肌皮瓣前界扩大的改良方法及其临床疗效和优点。方法  腓肠肌外侧头肌皮瓣的前界范围由腓骨体表投影扩大至胫骨前嵴，将创面的外缘作为皮瓣前缘的一部分。行前界扩大的改良腓肠肌外侧头肌皮瓣21例，修复的创面位于小腿上1/3段9例，中1/3段前内侧7例，中1/3段前外侧5例。21例皮瓣前缘均超过腓骨前缘，其中2例达胫骨前嵴，位于小腿前骨筋膜室表面的皮瓣部分宽度为2.5~7.0 cm，平均4.0 cm。 结果  19例皮瓣完全成活，2例皮瓣下缘分别为外踝上5 cm和3 cm的皮瓣远端出现部分坏死。 结论  腓肠肌外侧头肌皮瓣前界扩大改良后，皮瓣设计及手术操作简便，增加了皮瓣的宽度和有效长度，其适应症也相应扩大，可修复小腿中、上1/3段胫前创面，并且成活可靠。

        Objective   To introduce the modified lateral gastrocnemius myocutaneous flap with extended anterior margin and its clinical features. Methods   The anterior margin of the flap was extended from the overlying of fibula to the crista anterior tibiae, and anterior border located in lateral border of defects. 21 cases were treated with modified lateral gastrocnemius myocutaneous flaps, with 9 cases in upper 1/3 segment of the cnemis, 7 in anteriomedialis of middle 1/3 segment of the cnemis, and 5 in anteriolateral of middle 1/3 segment of the cnemis. The anterior border of all flaps exceeded crista anterior fibulae, and that of 2 flaps reached to the crista anterior tibiae. The width of flap on anterial compartment of the cnemis ranged from 2.5cm to 7.0cm, averagely 4.0 cm. Results  19 flaps survived well, however, marginal necrosis of distal end above external malleolus about 5cm and 3cm respectively, occurred in 2 cases.  Conclusions  With the extension of the effective width and length, the modified lateral gastrocnemius myocutaneous flaps are reliable for repairing soft tissue defect.