目的　介绍以桡动脉掌浅支为蒂的大鱼际皮瓣的显微解剖学基础，为该皮瓣游离移植修复指腹缺损提供解剖学依据。 方法　解剖20只成人新鲜尸体手标本，于远侧腕横纹上方约10 cm处解剖出桡动脉灌注红色乳胶，桡动脉的伴行静脉及头静脉灌注蓝色乳胶，在手术显微镜下进行解剖，观察大鱼际皮肤动脉、静脉、神经来源、分支及吻合情况。其中5只标本于桡动脉掌浅支起始处灌注墨汁，测量皮肤染色范围。 结果　桡动脉掌浅支起始处外径为（1.40±0.22）mm,长度为（2.0±0.5）cm，皮瓣可切取面积为2 　cm×3 cm～4 cm×5 cm。静脉回流有两种途径，神经支配以正中神经掌皮支为主。  结论　桡动脉掌浅支起始与走行恒定，口径适当，可设计以桡动脉掌浅支及其伴行静脉或浅静脉为蒂、带正中神经掌皮支的大鱼际皮瓣游离移植修复指腹缺损。

Objective　To explore anatomic basis of the thenar flap pedicled with the superficial palmar branch of the radials artery, for repairing ventral soft tissue defect of the finger.    Methods　Twenty fresh hand specimens were selected in this study. Red 1atex was perfused into radia1 arteries after the dissecting of the arteries 10cm above the dista1 wrist line, as well, blue latex into the accompanying veins and cephalic veins. The origins, distributions and anastomosis of the vessels and nerves in the thenar eminence area were observed under operation microscope. Five hands were perfused with ink at the beginning of the superficial palmar branch of the radials artery for measuring the ink extension areas.   Results　The origin diameter of the superficial palmar branch of the radials artery was about （1.40±0.22）mm, and the length （2.0±0.5）cm．The area of the flaps was about 2cm×3cm～4cm×5cm. The venous return of flaps passed through two routes, and the innervations of the flap mainly from ramus cutaneous volaris of mediani nerve.   Conclusions　The origin and courses of the superficial palmar branch of the radials artery is constant, which can be applied in the free grafting for repairing ventral defect of the finger.