Van Rossom Sam, Khatib Nidal, Holt Cathy, Van Assche Dieter, Jonkers Ilse
Human Movement Biomechanics Research Group, Department of Movement Sciences, Katholieke Universiteit Leuven, Leuven, Belgium.
Musculoskeletal Biomechanics Research Centre, University of Cardiff, Cardiff, United Kingdom.
Clin Biomech (Bristol). 2018 Dec;60:149-156. doi: 10.1016/j.clinbiomech.2018.10.015. Epub 2018 Oct 13.
Healthy cartilage is essential for optimal joint function. Although, articular cartilage defects are highly prevalent in the active population and hamper joint function, the effect of articular cartilage defects on knee loading is not yet documented. Therefore, the present study compared knee contact forces and pressures between patients with tibiofemoral cartilage defects and healthy controls. Potentially this provides additional insights in movement adaptations and the role of altered loading in the progression from defect towards OA.
Experimental gait data collected in 15 patients with isolated cartilage defects (8 medial involvement, 7 lateral-involvement) and 19 healthy asymptomatic controls was processed using a musculoskeletal model to calculate contact forces and pressures. Differences between two patient groups and controls were evaluated using Kruskal-Wallis tests and individually compared using Mann-Whitney-U tests (alpha <0.05).
The patients with lateral involvement walked significantly slower compared to the healthy controls. No movement adaptations to decrease the loading on the injured condyle were observed. Additionally, the location of loading was not significantly affected.
The current results suggest that isolated cartilage defects do not induce significant changes in the knee joint loading distribution. Consequently, the involved condyle will capture a physiological loading magnitude that should however be distributed over the cartilage surrounding the defect. This may cause local degenerative changes in the cartilage and in combination with inflammatory responses, might play a key role in the progression from articular cartilage defect to a more severe OA phenotype.
健康的软骨对于最佳关节功能至关重要。尽管关节软骨缺损在活跃人群中非常普遍并会妨碍关节功能，但关节软骨缺损对膝关节负荷的影响尚未见报道。因此，本研究比较了胫股关节软骨缺损患者与健康对照者之间的膝关节接触力和压力。这可能为运动适应性以及改变的负荷在从缺损发展至骨关节炎过程中的作用提供更多见解。
使用肌肉骨骼模型处理在15例孤立性软骨缺损患者（8例内侧受累，7例外侧受累）和19例健康无症状对照者中收集的实验性步态数据，以计算接触力和压力。使用Kruskal-Wallis检验评估两组患者与对照者之间的差异，并使用Mann-Whitney-U检验进行个体比较（α<0.05）。
外侧受累的患者与健康对照者相比行走速度明显较慢。未观察到为减少受伤髁负荷而进行的运动适应性改变。此外，负荷位置未受到显著影响。
目前的结果表明，孤立性软骨缺损不会引起膝关节负荷分布的显著变化。因此，受累髁将承受生理负荷大小，但该负荷应分布在缺损周围的软骨上。这可能会导致软骨局部退行性改变，并与炎症反应一起，可能在从关节软骨缺损发展为更严重的骨关节炎表型的过程中起关键作用。
