Sritharan Prasanna, Lin Yi-Chung, Richardson Sara E, Crossley Kay M, Birmingham Trevor B, Pandy Marcus G
La Trobe Sports and Exercise Medicine Research Centre, School of Allied Health, La Trobe University, Bundoora, Victoria, 3086, Australia.
Department of Mechanical Engineering, University of Melbourne, Victoria, Australia.
J Orthop Res. 2018 Feb 23. doi: 10.1002/jor.23883.
This study quantified the contributions by muscular, gravitational and inertial forces to the ground reaction force (GRF) and external knee adduction moment (EKAM) for knee osteoarthritis (OA) patients and controls walking at similar speeds. Gait data for 39 varus mal-aligned medial knee OA patients and 15 controls were input into musculoskeletal models to calculate the contributions of individual muscles and gravity to the fore-aft (progression), vertical (support), and mediolateral (balance) GRF, and the EKAM. The temporal patterns of contributions to GRF and EKAM were similar between the groups. Magnitude differences in GRF contributions were small but some reached significance. Peak GRF contributions were lower in patients except hamstrings in early-stance progression (p < 0.001) and gastrocnemius in late-stance progression (p < 0.001). Both EKAM peaks were higher in patients, due mainly to greater adduction contribution from gravity (p < 0.001) at the first peak, and lower abduction contributions from soleus (p < 0.001) and gastrocnemius (p < 0.001) at the second peak. Gluteus medius contributed most to EKAM in both groups, but was higher in patients during mid-stance only (p < 0.001). Differences in GRF contributions were attributed to altered quadriceps-hamstrings action as well as compensatory adaptation of the ankle plantarflexors to reduced gluteus medius action. The large effect of varus mal-alignment on the frontal-plane moment arms of the gravity, soleus, and gastrocnemius GRF contributions about the knee explained greater patient EKAM. Our results shed further light on how the EKAM contributes to altered knee-joint loads in OA and why some interventions may affect different portions of the EKAM waveform. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.
本研究量化了肌肉、重力和惯性力对膝骨关节炎（OA）患者和以相似速度行走的对照组的地面反作用力（GRF）和膝关节外展力矩（EKAM）的贡献。将39例内翻畸形的内侧膝OA患者和15例对照组的步态数据输入肌肉骨骼模型，以计算各肌肉和重力对前后（行进）、垂直（支撑）和内外侧（平衡）GRF以及EKAM的贡献。两组之间对GRF和EKAM贡献的时间模式相似。GRF贡献的大小差异较小，但有些达到了显著水平。除了在站立早期行进时的腘绳肌（p < 0.001）和站立后期行进时的腓肠肌（p < 0.001）外，患者的GRF峰值贡献较低。患者的两个EKAM峰值均较高，主要是由于第一个峰值时重力的内收贡献更大（p < 0.001），以及第二个峰值时比目鱼肌（p < 0.001）和腓肠肌（p < 0.001）的外展贡献较低。在两组中，臀中肌对EKAM的贡献最大，但仅在患者的站立中期较高（p < 0.001）。GRF贡献的差异归因于股四头肌 - 腘绳肌作用的改变以及踝关节跖屈肌对臀中肌作用降低的代偿性适应。内翻畸形对重力、比目鱼肌和腓肠肌GRF对膝关节的额面力臂的巨大影响解释了患者较大的EKAM。我们的结果进一步阐明了EKAM如何导致OA中膝关节负荷改变，以及为什么一些干预措施可能会影响EKAM波形的不同部分。©2018骨科研究协会。由Wiley Periodicals, Inc.出版。《骨科研究杂志》
