骨科英文书籍精读（91）｜尺骨鹰嘴骨折
FRACTURES OF THE OLECRANON
Two broad types of injury are seen: (1) a comminuted fracture which is due to a direct blow or a fall on the elbow; and (2) a transverse break, due to traction when the patient falls onto the hand while the triceps muscle is contracted. These two types can be further subclassified into (a) displaced and (b) undisplaced fractures. More severe injuries may be associated also with subluxation or dislocation of the ulno-humeral joint.
The fracture always enters the elbow joint and therefore damages the articular cartilage. With transverse fractures, the triceps aponeurosis sometimes remains intact, in which case the fracture fragments stay together.
Clinical features
A graze or bruise over the elbow suggests a comminuted fracture; the triceps is intact and the elbow can be extended against gravity. With a transverse fracture there may be a palpable gap and the patient is unable to extend the elbow against resistance.
X-ray
A properly orientated lateral view is essential to show details of the fracture, as well as the associated joint damage. Always check the position of the radial head – it may be dislocated.
Treatment
A comminuted fracture with the triceps intact should be treated as a severe ‘bruise’. Many of these patients are old and osteoporotic, and immobilizing the elbow will lead to stiffness. The arm is rested in a sling for a week; a further x-ray is obtained to ensure that there is no displacement and the patient is then encouraged to start active movements.
An undisplaced transverse fracture that does not separate when the elbow is x-rayed in flexion can be treated closed. The elbow is immobilized by a cast in about 60 degrees of flexion for 2–3 weeks and then exercises are begun. Repeat x-rays are needed to exclude displacement.
Displaced transverse fractures can be held only by splinting the arm absolutely straight – but stiffness in that position would be disastrous. Operative treatment is therefore strongly recommended. The fracture is reduced and held by tension band wiring.
Oblique fractures may need a lag screw, neutralised by a tension band system or plate.
Displaced comminuted fractures need a plate and often bone graft. In the osteoporotic bone of low-demand elderly patients, good results can be achieved with excision of fragments and reattachment of triceps to the ulna. If the coronoid portion of the joint is intact it will reduce the risk of instability. Following operation, early mobilization should be encouraged.
Complications
Stiffness used to be common, but with secure internal fixation and early mobilization the residual loss of movement should be minimal.
Non-union sometimes occurs after inadequate reduction and fixation. If elbow function is good, it can be ignored; if not, rigid internal fixation and bone grafting will be needed.
Ulnar nerve symptoms can develop. These usually settle spontaneously.
Osteoarthritis is a late complication, especially if reduction is less than perfect. This can usually be treated symptomatically.
---from 《Apley’s System of Orthopaedics and Fractures》
重点词汇整理：
subclassified /sʌb'klæsifai/vt. 将…归入亚纲;被细分类的
subluxation /,sʌblʌk'seiʃən/n. [外科] 半脱位；不全脱位
aponeurosis /,æpənʊ'rosɪs/n. [解剖] 腱膜
palpable/ˈpælpəbl/adj. 明显的；可感知的；易觉察的
orientate /ˈɔːriənteɪt/v. 朝向，面向；确定方向；使熟悉，适应；以……为重点（同 orient）
tension band 张力带
low-demand低需求
residual /rɪˈzɪdʒuəl/adj. （数量）剩余的
rigid internal fixation 坚强内固定
This can usually be treated symptomatically.通常可以对症治疗。
百度翻译：
鹰嘴骨折
常见两种类型的损伤：（1）粉碎性骨折，由于直接打击或摔在肘部；和（2）横向骨折，由于牵引，当病人跌倒在手上，而三头肌收缩。这两种类型可进一步分为（a）移位骨折和（b）未移位骨折。更严重的损伤也可能与肱尺骨关节半脱位或脱位有关。
骨折总是进入肘关节，从而损伤关节软骨。横断性骨折，三头肌腱膜有时保持完整，在这种情况下，骨折碎片保持在一起。
临床特征
肘部擦伤或瘀伤提示粉碎性骨折；三头肌完整，肘部可在重力作用下伸展。横断性骨折可能有一个明显的间隙，患者无法伸展肘关节抵抗阻力。
X射线
正确定位的侧视图对于显示骨折的细节以及相关的关节损伤至关重要。始终检查径向头的位置-它可能错位。
治疗
三头肌完整的粉碎性骨折应被视为严重的“瘀伤”。这些病人中有许多是老年人和骨质疏松症，固定肘关节会导致僵硬。手臂放在吊带上休息一周；再做一次x光检查以确保没有移位，然后鼓励患者开始积极活动。
当肘关节屈曲时x光片不能分离的未移位的横向骨折可以闭合治疗。肘关节用石膏固定，弯曲约60度，持续2-3周，然后开始运动。需要重复x光来排除位移。
移位的横向骨折只能用夹板将手臂固定在绝对直的位置上，但僵硬的姿势将是灾难性的。因此强烈建议手术治疗。骨折被减少并由张力带固定。
斜向骨折可能需要一个拉力螺钉，由张力带系统或钢板中和。
移位的粉碎性骨折需要钢板，通常需要植骨。对于低需量老年骨质疏松症患者，切除碎片并将三头肌重新附着在尺骨上可取得良好效果。如果关节的冠状部分是完整的，它将减少不稳定的风险。术后应鼓励早期动员。
并发症
僵硬过去是常见的，但有了安全的内固定和早期活动，残余运动损失应该是最小的。
骨折愈合后有时出现复位不稳和不固定。如果肘关节功能良好，可以忽略不计，否则需要进行坚固的内固定和植骨。
尺神经症状会出现。这些通常是自发的。
骨关节炎是一种晚期并发症，尤其是在复位不够理想的情况下。这通常可以对症治疗。