Graduate School of Health Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394, Japan.
Department of Rehabilitation, Tsuchiura Kyodo General Hospital, 4-1-1 Otsuno, Tsuchiura, Ibaraki 300-0028, Japan.
Medicina (Kaunas). 2020 Aug 28;56(9):437. doi: 10.3390/medicina56090437.
: Decreased knee flexion in the swing phase of gait can be one of the causes of falls in severe knee osteoarthritis (OA). The quadriceps tendon is one of the causes of knee flexion limitation; however, it is unclear whether the stiffness of the quadriceps tendon affects the maximum knee flexion angle in the swing phase. The purpose of this study was to clarify the relationship between quadriceps tendon stiffness and maximum knee flexion angle in the swing phase of gait in patients with severe knee OA. : This study was conducted from August 2018 to January 2020. Thirty patients with severe knee OA (median age 75.0 (interquartile range 67.5-76.0) years, Kellgren-Lawrence grade: 3 or 4) were evaluated. Quadriceps tendon stiffness was measured using Young's modulus by ShearWave Elastography. The measurements were taken with the patient in the supine position with the knee bent at 60° in a relaxed state. A three-dimensional motion analysis system measured the maximum knee flexion angle in the swing phase. The measurements were taken at a self-selected gait speed. The motion analysis system also measured gait speed, step length, and cadence. Multiple regression analysis by the stepwise method was performed with maximum knee flexion angle in the swing phase as the dependent variable. : Multiple regression analysis identified quadriceps tendon Young's modulus (standardized partial regression coefficients [] = -0.410; = 0.013) and gait speed ( = 0.433; = 0.009) as independent variables for maximum knee flexion angle in the swing phase (adjusted coefficient of determination = 0.509; < 0.001). : Quadriceps tendon Young's modulus is a predictor of the maximum knee flexion angle. Clinically, decreasing Young's modulus may help to increase the maximum knee flexion angle in the swing phase in those with severe knee OA.
在步态摆动相时膝关节屈曲减少可能是严重膝骨关节炎（OA）患者跌倒的原因之一。股四头肌肌腱是膝关节屈曲受限的原因之一；然而，股四头肌肌腱的僵硬是否会影响摆动相时的最大膝关节屈曲角度尚不清楚。本研究旨在阐明严重膝 OA 患者步态摆动相时股四头肌肌腱僵硬与最大膝关节屈曲角度之间的关系。
这项研究是在 2018 年 8 月至 2020 年 1 月进行的。共评估了 30 名严重膝 OA 患者（中位数年龄 75.0（四分位间距 67.5-76.0）岁，Kellgren-Lawrence 分级：3 或 4）。使用剪切波弹性成像测量股四头肌肌腱的杨氏模量来评估股四头肌肌腱的僵硬程度。在膝关节处于 60°放松状态的仰卧位下进行测量。使用三维运动分析系统测量摆动相时的最大膝关节屈曲角度。测量时采用患者自主选择的步行速度。运动分析系统还测量了步行速度、步长和步频。以摆动相时的最大膝关节屈曲角度为因变量，采用逐步法进行多元回归分析。
多元回归分析确定股四头肌肌腱杨氏模量（标准化偏回归系数 []=-0.410； =0.013）和步行速度（ =0.433； =0.009）为摆动相时最大膝关节屈曲角度的独立变量（调整后的决定系数 =0.509；<0.001）。
股四头肌肌腱杨氏模量是最大膝关节屈曲角度的预测因子。临床上，降低杨氏模量可能有助于增加严重膝 OA 患者摆动相时的最大膝关节屈曲角度。
