Gómez-Vallejo Jesús, Roces-García Jorge, Moreta Jesús, Donaire-Hoyas Daniel, Gayoso Óscar, Marqués-López Fernando, Albareda Jorge
Department of Orthopaedic Surgery, Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain.
Department of Construction and Manufacturing Engineering, University of Oviedo, Oviedo, Spain.
Arthroplast Today. 2021 Feb 1;7:167-176. doi: 10.1016/j.artd.2020.11.022. eCollection 2021 Feb.
The objective is to compare, by the means of finite elements analysis, the biomechanical behavior of a conventional stem of proven performance with a short stem based on the same fixation principles.
A 3D femur was modeled from CT scan data, and real bone density measures were incorporated into it. Load stresses were applied to that bone in 3 different scenarios: without prosthesis, with the conventional stem, and with the short stem. Different bone loading patterns were compared by Gruen's zones both visually and statistically using Welch's test.
The implantation of a stem generates a certain degree of stress shielding in the surrounding bone, but the pattern of the change is very similar in the compared stem models. Although there is statistical significance ( < 0.01) in the mean stress variation in most of the Gruen's zones, the magnitude of the difference is always under 2 MPa (range: 0.01 - 1.74 MPa).
The bone loading patterns of the traditional stem and the short stem are very similar. Although there is no evidence of a link between biomechanics and clinical outcomes, our results may suggest that theoretical advantages of short stems can be exploited without the fear of altering bone loading patterns.
目的是通过有限元分析方法，比较基于相同固定原则的传统性能良好的股骨柄与短柄的生物力学行为。
根据CT扫描数据建立三维股骨模型，并将实际骨密度测量值纳入其中。在三种不同情况下对该骨骼施加负荷应力：无假体、有传统股骨柄和有短柄。使用韦尔奇检验，通过Gruen分区在视觉上和统计学上比较不同的骨负荷模式。
股骨柄的植入在周围骨骼中产生一定程度的应力遮挡，但在比较的股骨柄模型中，变化模式非常相似。虽然在大多数Gruen分区的平均应力变化中有统计学意义（<0.01），但差异幅度始终在2MPa以下（范围：0.01 - 1.74MPa）。
传统股骨柄和短柄的骨负荷模式非常相似。虽然没有证据表明生物力学与临床结果之间存在联系，但我们的结果可能表明，可以利用短柄的理论优势，而不必担心改变骨负荷模式。
