目的    研究第1掌心动脉掌骨颈尺侧穿支与第2掌背动脉及指蹼动脉间的吻合类型, 为第2掌背动脉皮瓣的安全设计切取提供解剖学基础。 方法    成人新鲜手标本39侧, 用红色乳胶灌注动脉。解剖观测第1掌心动脉掌骨颈尺侧穿支的起源、走行、外径以及与第2掌背动脉和指蹼动脉间的吻合方式。  结果     第1掌心动脉掌骨颈尺侧穿支在第2掌骨颈处起自第1掌心动脉，起始处直径（0.57±0.20）mm，沿第2掌骨颈尺侧和骨间肌的间隙穿向背侧，与第2掌背动脉及指蹼动脉间形成吻合。依其与掌背动脉及指蹼动脉的吻合特点可分4型：Ⅰ.无吻合型（38.46%）；Ⅱ. “T” 型（33.33%）；Ⅲ. “Y”型（25.64%）；IV. “π” 型（2.56%）。 结论    28.20%的第2掌背动脉与指蹼动脉间并非直接吻合，而是通过第1掌心动脉掌骨颈尺侧穿支间接吻合（ “Y” 型、 “π” 型吻合），当遇到这两种情况时，术中很容易破坏第2掌背动脉与指蹼动脉间的吻合连续性，导致第2掌背动脉皮瓣的切取困难甚至失败。

 Objective    To study the anastomotic types between the first metacarpal artery metacarpal neck ulnar perforator, the second dorsal metacarpal artery and the webbed artery, so as to provide anatomical basis for the safe design and incision of the second dorsal metacarpal artery flap.    Methods    A total of 39 fresh adult cadaveric hands were collected. All the arteries of those hands were perfused with red latex. Anatomical observation under the microscope was recorded not only the origin, course, and outer diameter of the first metacarpal artery metacarpal neck ulnar perforator, but also the anastomosis between the second dorsal metacarpal artery and the webbed artery.    Results    The first metacarpal artery metacarpal neck ulnar perforator branch started at the second metacarpal neck from the first metacarpal artery, with an initial diameter of (0.57±0.20) mm, and passed dorsally along the gap between the ulnar side of the second metacarpal artery and the interosseous muscles, forming anastomosis with the second dorsal metacarpal artery and the webbed artery. According to the anastomotic characteristics of the dorsal metacarpal artery and the webbed artery, it could be divided into 4 types: Ⅰ. Non-anastomosis type (accounting for 38.46%); Ⅱ. "T" type (accounting for 33.33%); Ⅲ. "Y" type (accounting for 25.64%); IV. "π" type (accounting for 2.56%). Conclusions   The anastomosis between 28.20% of the second dorsal metacarpal artery and the webbed artery are not direct, but indirectly anastomosed through the first metacarpal artery metacarpal neck ulnar perforator ("Y" type, "π" type anastomosis). In these two cases, it is easy to destroy the anastomotic continuity between the second dorsal metacarpal artery and the webbed artery during the operation, which may cause the difficulty or even failure of the second dorsal metacarpal artery flap operation.