骨科英文书籍精读（17）｜石膏固定和并发症
Technique
After the fracture has been reduced, stockinette is threaded over the limb and the bony points are protected with wool. Plaster is then applied. While it is setting the surgeon moulds it away from bony prominences; with shaft fractures three-point pressure can be applied to keep the intact periosteal hinge under tension and thereby maintain reduction.
If the fracture is recent, further swelling is likely; the plaster and stockinette are therefore split from top to bottom, exposing the skin. Check x-rays are essential and the plaster can be wedged if further correction of angulation is necessary.
With fractures of the shafts of long bones, rotation is controlled only if the plaster includes the joints above and below the fracture. In the lower limb, the knee is usually held slightly flexed, the ankle at a right angle and the tarsus and forefoot neutral (this ‘plantigrade’ position is essential for normal walking). In the upper limb the position of the splinted joints varies with the fracture. Splintage must not be discontinued (though a functional brace may be substituted) until the fracture is consolidated; if plaster changes are needed, check x-rays are essential.
Complications
Plaster immobilization is safe, but only if care is taken to prevent certain complications. These are tight cast, pressure sores and abrasion or laceration of the skin.
Tight cast The cast may be put on too tightly, or it may become tight if the limb swells. The patient complains of diffuse pain; only later – sometimes much later – do the signs of vascular compression appear.
The limb should be elevated, but if the pain persists, the only safe course is to split the cast and ease it open: (1) throughout its length and (2) through all the padding down to skin. Whenever swelling is anticipated the cast should be applied over thick padding and the plaster should be split before it sets, so as to provide a firm but not absolutely rigid splint.
Pressure sores Even a well-fitting cast may press upon the skin over a bony prominence (the patella, heel, elbow or head of the ulna). The patient complains of localized pain precisely over the pressure spot. Such localized pain demands immediate inspection through a window in the cast.
Skin abrasion or laceration This is really a complication of removing plasters, especially if an electric saw is used. Complaints of nipping or pinching during plaster removal should never be ignored; a ripped forearm is a good reason for litigation.
Loose cast Once the swelling has subsided, the cast may no longer hold the fracture securely. If it is loose, the cast should be replaced.
---from 《Apley’s System of Orthopaedics and Fractures》P687-688
重点词汇整理：
stockinette/,stɑkɪ'nɛt/n. 弹力织物；布袋；松紧织物（等于stockinet）
thread over 穿过 /θred/n. 线；螺纹；思路；衣服；线状物；玻璃纤维；路线vt. 穿过；穿线于；使交织
bony points 骨折端
mould /moʊld/v. （用模具）浇铸，塑造；对……施加影响；将…塑造成；紧贴于，吻合（轮廓）；使长霉n. 模具
prominence/ˈprɑːmɪnəns/n. 突出；显著；突出物；卓越
periosteal hinge骨膜铰链/hɪndʒ/n. 铰链，折叶；关键，转折点；枢要，中枢
split /splɪt/n. 劈开；裂缝adj. 劈开的
wedge /wedʒ/n. 楔子；楔形物；不和v. 楔入；挤进；楔住
further correction of angulation角度进一步修正
flexed 弯曲的
tarsus /'tɑ:səs/n. 睑板；跗骨；踝骨
plantigrade/'plæntə,gred/n. 踯行动物adj. 踯行的；踯行类的
diffuse pain弥散性疼痛
vascular compression血管压迫
padding /ˈpædɪŋ/n. 填料；垫料v. 填补（pad的ing形式）
Pressure sores压疮；褥疮
the patella, heel, elbow or head of the ulna膝盖骨，脚跟，肘部或尺骨头
Skin abrasion or laceration 皮肤擦伤或撕裂
/əˈbreɪʒn/
n. 磨损；磨耗；擦伤
/ˌlæsəˈreɪʃn/
n. 裂伤；撕裂；割破
electric saw电锯
nipping or pinching夹紧或捏
litigation /ˌlɪtɪˈɡeɪʃn/n. 诉讼；起诉
subsided, /səbˈsaɪd/vi. 平息；减弱；沉淀；坐下
百度翻译：
技术要点
骨折复位后，在四肢上穿上粗纤维网，用羊毛保护骨点。然后涂上灰泥。当它设置时，外科医生将它从骨性前凸处塑造出来；对于骨干骨折，可以施加三点压力，以保持完整的骨膜铰链处于张力下，从而保持复位。
如果骨折是新近发生的，可能会进一步肿胀；因此，石膏和粗晶石会从上到下分开，露出皮肤。检查x光片是否正确，如果需要进一步校正角度，可以楔入石膏。
对于长骨轴的骨折，只有当石膏包括骨折上方和下方的关节时，旋转才受到控制。在下肢，膝关节通常保持轻微弯曲，踝关节保持直角，跗骨和前脚保持中立（这种“planti�grade”姿势对正常行走是必不可少的）。在上肢，夹板关节的位置随骨折而变化。在骨折愈合之前，夹板固定不能中断（尽管可以更换功能性支撑）；如果需要更换石膏，则必须检查x光片。
并发症
石膏固定是安全的，但必须注意防止某些并发症。这些是紧绷的石膏，压疮和皮肤的磨损或撕裂。
绷紧石膏 绷紧石膏，如果四肢肿胀，石膏可能会绷紧。病人抱怨弥漫性疼痛；只有在晚些时候，有时是晚些时候，才会出现血管压迫的迹象。
肢体应该抬高，但如果疼痛持续，唯一安全的方法是分开石膏，并放松它：（1）整个长度和（2）通过所有垫到皮肤。无论何时出现肿胀，石膏都应覆盖在厚垫上，石膏应在凝固前裂开，以便提供一个坚固但不是绝对坚硬的夹板。
压疮 即使是一个合适的石膏可能会压在皮肤上的骨性突起（髌骨，脚跟，肘部或尺骨头）。病人抱怨局部疼痛正好在压点上。这种局部疼痛需要通过石膏窗立即检查。
皮肤磨损或撕裂这是去除膏药的一个真正的并发症，特别是如果使用电锯。切忌忽视拔除前足时夹伤或夹伤的投诉；前臂撕裂是提起诉讼的一个很好的理由。
松动的石膏一旦肿胀消退，石膏可能不再牢固地固定骨折。如果松动，应更换铸件。