【专题文献】之人工髋关节置换——下肢假体周(5)

【专题文献】之人工髋关节置换——下肢假体周围骨折的处理

重要的。

假体周围骨折的评估应该是标准化的。应该调查病人的生化和血液学检查，以评估他们适合手术。 在放射学检查方面，获得高质量的放射学图片是极重要的，对放射学资料应仔细评估，同之前的资料进行比较。CT扫描可能很有用，假如有足够的内植物伪影抵制。

Management

If the patient is unfit for surgical treatment, closed reduction can be attempted; but the associated prolonged bed rest can lead to serious complications. Malunion is a major concern in this group as it can be detrimental to function, and can make future revision, if that becomes possible, extremely challenging.

The surgical management of periprosthetic fractures depends on the site of the fracture, the bone quality and the stability of the components. When the stem is stable, fixation of the fracture should be performed, either open or closed. Special consideration should be given to transverse fractures at the tip of the stem. These are very difficult to treat conventionally and many surgeons advocate stem revision despite the prosthesis itself being stable.

处理

如果病人不适合手术治疗，应尝试闭合复位。但是与之相同的延长的卧床休息能导致严重的并发症。在此种方式下，畸形愈合是个主要问题，它能影响功能，并在未来可能可以进行的翻修时带来极度挑战。

外科处理假体周围骨折依赖于骨折部位、骨质量和假体稳定性。当假体干是稳定的，应该固定骨折，不管是开放或闭合方式。应对假体尾部的横形骨折给予特别注意，按照常规治疗此种骨折非常困难，尽管假体本身是稳定的，但很多外科医生倡导假体干翻修。

Historically Ogden in 1972 used a long plate designed to accommodate pre-existing intramedullary devices. It had slots to accommodate wires and bands. However, biomechanical analysis showed that these resulted in high tensile stress at the fracture site and stress shielding at the proximal lateral cortex, leading to fractures below the plate and component loosening. The Partridge system, introduced in 1982, consisted of a nylon plate and straps which were introduced around the fracture. Over time it proved to be unsuccessful, with poor results, especially in more distal fractures, largely due to band loosening. Another popular device was the Mennen Plate, a paraskeletal clamp-on plate device, but reports of its use were controversial. It gave semi-rigid stability and was first introduced for non weight-bearing bones, but Lam et al. advocated its suitability and use for femoral periprosthetic fractures. 14 The general consensus is that they give sub-optimal results were technically difficult to apply, and the surgical approach and exposure were not soft tissue friendly.

历史上，Ogden在1972年使用一块具有适应之前存在的髓内装置的设计的长钢板。它具有沟槽可以应用钢丝或捆绑带。然而，生物力学分析特别是更远端骨折，很大程度上归咎于捆绑带松动。另一个流行的器械是Mennen钢板，一种环报器钳夹钢板，但使其此种钢板的报道结果手术入路和暴露对软组织损伤较大，结果并不是很理想。 显示这导致骨折部位高度应力集中和近端外侧皮质的应力遮挡，导致钢板下方骨折和假体松动。久而久之，己证明此方法不成功，结果较差，是有争议。它有半坚硬稳定性，最初用于非负重骨折，但Lam等倡导此器械适用并使用于假体周围骨折。意见一致的是，此器械技术较困难，

Current concepts for the treatment of any fracture should follow AO principles. If the prosthesis is satisfactory both clinically and radiologically the focus should be on treating the fracture on its own merits. Thus if the fracture is distal to the tip of the femoral stem, the use of conventional DCP, DCS or LCP plates should be considered (Figure 1). The LCP plate is a newer development in plate osteosynthesis which has revolutionised the principles of internal fixation, providing better purchase in low quality bones, and gives excellent angular stability. Chakravarthy et al. confirmed this.15 The angular stability provided by the locking screws abolishes the need to compress the plate on to the bone, thus avoiding compression and strangulation of the periosteal blood supply.

治疗任何骨折的当前理念应该遵从AO原则。如果假体在临床和放射学方面都满意，则应关注于治疗骨折本身。因此如果骨折在股骨假体干尾部的远端，应当考虑使用传统DCP，DCS或LCP钢板（图1）。在钢板接骨术中，LCP钢板是一种较新的进展，它具有***性的内固定原则，对于较低的骨质量提供了更好的稳定性，并有优秀的角度稳定性。Chakravarthy等证实了这种优点。由锁定螺钉带来的角度稳定性，不需要钢板与骨的摩擦，因此避免了骨膜血供的压迫。

图1