Service de Chirurgie Orthopédique et de Traumatologie, Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, 1 avenue Molière, 67098 Strasbourg cedex, France; Laboratoire ICube, Université de Strasbourg- CNRS, 2 rue Boussingault, 67000 Strasbourg, France.
Service de Chirurgie Orthopédique et de Traumatologie, Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, 1 avenue Molière, 67098 Strasbourg cedex, France.
Orthop Traumatol Surg Res. 2022 Nov;108(7):103400. doi: 10.1016/j.otsr.2022.103400. Epub 2022 Sep 9.
Peri-prosthetic fractures (PPFs) are steadily rising in number due to population ageing and increased performance of joint replacement procedures. Although PPFs without implant loosening are usually managed by internal fixation, no consensus exists regarding the optimal construct. The primary objective of this study was to compare five constructs, and the secondary objective was to compare sub-groups of mono-cortical screw constructs, with the goal of identifying the method most appropriate for diaphyseal fracture fixation when prosthetic material is present within the intra-medullary canal.
The primary hypothesis was that fixation using bi-cortical screws, i.e., the current reference standard, was superior over other fixation methods. The secondary hypothesis was that adding double cerclage to mono-cortical screw fixation provided the greatest mechanical strength.
Synthetic osteoporotic bone was used to compare five methods for locking-screw fixation of a femoral diaphyseal plate. One method involved bi-cortical screws and four methods mono-cortical screws, with no cerclage wire, a single cerclage wire on either side positioned near or at a distance from the fracture, and two cerclage wires on both sides of the fracture. A complex fracture was simulated by creating a 2-cm diaphyseal gap. Load-to-failure was determined by applying compression loading along the anatomical axis of the femur.
Bi-cortical screw fixation provided greater mechanical strength than did three of the four mono-cortical screw constructs. The exception was the mono-cortical-screw and double-cerclage construct, for which no significant difference was found compared to bi-cortical screw fixation. Thus, mono-cortical screw fixation with double cerclage may be the best alternative when presence of an implant in the intra-medullary canal precludes bi-cortical screw fixation.
The findings from this study have clear implications for clinical practice. The study hypotheses were partly confirmed. The absence of a significant difference between the reference-standard bi-cortical screw fixation method and mono-cortical screw fixation with double cerclage, combined with the results regarding the secondary objective, suggest that mono-cortical screws plus double cerclage deserve preference in patients with an intra-medullary implant. Clinical studies are needed to assess the results of this bench study.
IV, bench study.
由于人口老龄化和关节置换手术数量的增加，假体周围骨折（PPF）的数量稳步上升。虽然没有假体松动的 PPF 通常通过内固定治疗，但对于最佳固定结构尚无共识。本研究的主要目的是比较五种固定结构，次要目的是比较单皮质螺钉固定结构的亚组，目的是确定在髓内管内存在假体材料时，最适合骨干骨折固定的方法。
主要假设是使用双皮质螺钉固定，即目前的参考标准，优于其他固定方法。次要假设是在单皮质螺钉固定中添加双环扎线可提供最大的机械强度。
使用合成骨质疏松骨来比较锁定螺钉固定股骨骨干板的五种方法。一种方法涉及双皮质螺钉，四种方法涉及单皮质螺钉，无环扎线，在骨折附近或远离骨折处的每一侧放置一根单环扎线，以及在骨折两侧放置两根环扎线。通过创建 2 厘米骨干间隙来模拟复杂骨折。通过沿股骨解剖轴施加压缩载荷来确定失效载荷。
与四种单皮质螺钉固定结构中的三种相比，双皮质螺钉固定提供了更大的机械强度。例外的是单皮质螺钉和双环扎固定结构，与双皮质螺钉固定相比，没有发现显著差异。因此，当髓内存在植入物时，双皮质螺钉固定不可行时，单皮质螺钉固定加双环扎可能是最佳选择。
本研究的结果对临床实践具有明确的意义。研究假设部分得到证实。缺乏参考标准双皮质螺钉固定方法与单皮质螺钉固定加双环扎之间的显著差异，加上次要目标的结果，表明在髓内植入物的患者中，单皮质螺钉加双环扎应优先考虑。需要进行临床研究来评估这项基础研究的结果。
IV，基础研究。
