It's gonna be a hairline metacarpal fracture.

就是掌轻微裂。

It's a minor break in the fifth metacarpal.

第五掌有一点小。

Clean fracture of the metacarpal bone.

掌干净。

But the underlying structures of the humerus, radius and ulna, and metacarpals, are shared.

但是肱、桡和以及掌的基础结构是共享的。

Broken knuckles, also known as metacarpal fractures, are fairly common, leading to the term “boxer’s fracture” or “brawler’s fracture”.

指关节， 为掌， 相当常见，导致术语“拳击手”或“斗殴者” 。

These muscles include the flexor digitorum profundus which flexes the fingers at the interphalangeal joints, and the extensor digitorum which hyperextend them at the metacarpal phalangeal joint.

前臂肌群包括指深屈肌（在指间关节处使手指屈曲）及指伸肌（在掌指关节处使手指过伸）。

Finally, both the ulnar and median nerves innervate the lumbricals, which are 4 muscles that extend the fingers at the interphalangeal joints, and keep them flexed at the metacarpal phalangeal joints.

最后，神经和正中神经都支配蚓状肌，这四条蚓状肌能使指间关节的手指伸直，同时掌指关节保持屈曲位。