There was damage to the second metacarpal, but the first MCP joint was completely crushed.

第二掌受到了损伤，第一掌指关节完全粉碎了。

It's gonna be a hairline metacarpal fracture.

就掌轻微裂。

It's a minor break in the fifth metacarpal.

第五掌有一点。

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

肱、桡和尺以及掌的基础结构共享的。

Clean fracture of the metacarpal bone.

掌了。

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

指关节， 也称为掌， 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，尺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。