骨科英文书籍精读（113）｜孟氏骨折（1）
MONTEGGIA FRACTURE DISLOCATION OF THE ULNA
The injury described by Monteggia in the early nineteenthth century (without benefit of x-rays!) was a fracture of the shaft of the ulna associated with dislocation of the proximal radio-ulnar joint; the radiocapitellar joint is inevitably dislocated or subluxated as well. More recently the definition has been extended to embrace almost any fracture of the ulna associated with dislocation of the radio-capitellar joint, including trans-olecranon fractures in which the proximal radioulnar joint remains intact. If the ulnar shaft fracture is angulated with the apex anterior (the commonest type) then the radial head is displaced anteriorly; if the fracture apex is posterior, the radial dislocation is posterior; and if the fracture apex is lateral then the radial head will be laterally displaced. In children, the ulnar injury may be an incomplete fracture (greenstick or plastic deformation of the shaft).
Mechanism of injury
Usually the cause is a fall on the hand; if at the moment of impact the body is twisting, its momentum may forcibly pronate the forearm. The radial head usually dislocates forwards and the upper third of the ulna fractures and bows forwards. Sometimes the causal force is hyperextension.
Clinical features
The ulnar deformity is usually obvious but the dislocated head of radius is masked by swelling. A useful clue is pain and tenderness on the lateral side of the elbow. The wrist and hand should be examined for signs of injury to the radial nerve.
X-ray
With isolated fractures of the ulna, it is essential to obtain a true anteroposterior and true lateral view of the elbow. In the usual case, the head of the radius (which normally points directly to the capitulum) is dislocated forwards, and there is a fracture of the upper third of the ulna with forward bowing. Backward or lateral bowing of the ulna (which is much less common) is likely to be associated with, respectively, posterior or lateral displacement of the radial head. Trans-olecranon fractures, also, are often associated with radial head dislocation.
Bado主要根据桡骨头脱位与尺骨骨折方向进行分型。Ⅰ型（前脱位）：桡骨头向前脱位，尺骨干部或尺骨近端干骺端区域短斜行或青枝骨折；Ⅱ型（后脱位）：桡骨头向后/后外脱位，在儿童尺骨常为干骺端骨折；Ⅲ型（外侧脱位）：桡骨头向外脱位，尺骨干骺端青枝骨折；Ⅳ型（伴桡骨干骨折的前脱位）：损伤与Ⅰ型类似，尺桡骨同水平骨干骨折。
---from 《Apley’s System of Orthopaedics and Fractures》
重点词汇整理：
inevitably/ɪnˈevɪtəbli/adv. 不可避免地；必然地
apex/ˈeɪpeks/n. 顶点；尖端
forcibly /ˈfɔːrsəbli/adv. 用力地；用武力地，强制地；有说服力
pronate /ˈproʊˌneɪt/旋前
百度翻译：
尺骨孟氏骨折脱位
蒙特吉亚在19世纪早期描述的伤害（没有x光的帮助！）尺骨骨干骨折伴近侧桡尺关节脱位，桡小头关节不可避免地脱位或半脱位。最近，这一定义被扩展到几乎所有与桡骨头关节脱位相关的尺骨骨折，包括近侧桡尺关节完整的尺骨鹰嘴骨折。尺骨干骨折与先端成角（最常见的类型），桡骨头前移；骨折尖后，桡骨脱位正前方；骨折尖外侧，桡骨头侧向移位。在儿童，尺骨损伤可能是不完全骨折（绿枝或骨干塑性变形）。
损伤机制
通常原因是手上的摔倒；如果在撞击的那一刻，身体在扭动，它的力矩可能会强行旋前前臂。桡骨头通常向前脱位，尺骨上三分之一骨折并向前弓。有时因果力是超延伸的。
临床特征
尺骨畸形通常很明显，但脱臼的桡骨头部肿胀。一个有用的线索是肘关节外侧的疼痛和触痛。手腕和手应该检查桡神经损伤的迹象。
X射线
对于尺骨孤立性骨折，必须获得肘部的真正的前后侧视图。通常情况下，桡骨的头部（通常直接指向小头）向前移位，尺骨上三分之一处骨折，前弓。尺骨的后弯或侧弯（这种现象不太常见）可能分别与桡骨头的后向或侧向移位有关。尺骨鹰嘴骨折也常伴有桡骨头脱位。