骨科英文书籍精读（92）｜肘关节脱位（1）

⾻科英⽂书籍精读（92）｜肘关节脱位（1）
DISLOCATION OF THE ELBOW
Dislocation of the ulno-humeral joint is fairly common – more so in adults than in children. Injuries are usually classified according to the direction of displacement. However, in 90% of cases the radioulnar complex is displaced posteriorly or posterolaterally, often together with fractures of the restraining bony processes.
Mechanism of injury and pathology
The cause of posterior dislocation is usually a fall on the outstretched hand with the elbow in extension. Disruption of the capsule and ligaments structures alone can result in posterior or posterolateral dislocation. However, provided there is no associated fracture, reduction will usually be stable and recurrent dislocation unlikely. The combination of ligamentous disruption and fracture of the radial head, coronoid process or olecranon process (or, worse still, several fractures) will render the joint more unstable and, unless the fractures are reduced and fixed, liable to redislocation.
Once posterior dislocation has taken place, lateral shift may also occur. Soft tissue disruption is often considerable and surrounding nerves and vessels may be damaged. Although certain common patterns of fracture-dislocation are recognized (based on the particular combination of structures involved), highenergy injuries do not necessarily follow any rules. A classic example is the so-called sideswipe injury which occurs, typically, when a car-driver’s elbow, protruding through the window, is struck by another vehicle.
The result is forward dislocation with fractures of any or all of the bones around the elbow; soft-tissue damage (including neurovascular injury) is usually severe.
Clinical features
The patient supports his forearm with the elbow in slight flexion. Unless swelling is severe, the deformity is obvious. The bony landmarks (olecranon and epicondyles) may be palpable and abnormally placed.
However, in severe injuries pain and swelling are so marked that examination of the elbow is impossible. Nevertheless, the hand should be examined for signs of vascular or nerve damage.
X-ray
X-ray examination is essential (a) to confirm the presence of a dislocation and (b) to identify any associated fractures. It is often only when the elbow is screened at the time of surgery that the full extent of the injury can be established.
---from 《Apley’s System of Orthopaedics and Fractures》
临床特征
病⼈⽤肘关节⽀撑前臂，使其轻微弯曲。

除⾮肿胀严重，否则畸形是明显的。

⾻标志物（鹰嘴和上髁）可以触摸到并且位置异常。

然⽽，在严重的伤害中疼痛和肿胀是如此
因为肘部检查是不可能的。

然⽽，⼿部应该检查⾎管或神经损伤的迹象。

X射线
X光检查对于（a）确认是否存在脱位和（b）识别任何相关⾻折⾄关重要。

通常只有在⼿术时对肘关节进⾏检查，才能确定损伤的全部程度。