Department of Preventive Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Department of Preventive Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Gait Posture. 2021 Mar;85:290-297. doi: 10.1016/j.gaitpost.2021.02.006. Epub 2021 Feb 13.
The human tracking algorithm called OpenPose can detect joint points and measure segment and joint angles. However, the validity of gait analysis using OpenPose has not been examined yet.
What is the validity of OpenPose-based gait analysis?
Twenty-four healthy young people participated in this study. The participants were assessed during walking and running. Pelvic segment angles, and hip, knee, and ankle joint angles during treadmill walking and running were measured using VICON. Simultaneously, images were captured using digital cameras from the right and back sides. After processing with OpenPose, the corresponding angles were measured from the estimated joint points. To validate these estimations, linear regression analysis was performed, and intraclass correlation coefficients [ICCs (2, 1)] between the data obtained by OpenPose and VICON were calculated. Furthermore, the agreement between the data obtained by OpenPose and VICON was assessed by Bland-Altman analysis.
For most ranges of motion (ROM) in the sagittal plane, the hip, knee, and ankle joints had large coefficients of determination, without proportional biases. For most peak angles in the sagittal plane, the knee and ankle joints had large coefficients of determination without proportional biases, although the hip joint had nonsignificant coefficients of determination and proportional biases. In particular, for the hip flexion-extension ROM and peak knee flexion angle during running and the knee ROM during slow walking, the ICCs showed good to excellent agreement. However, for the parameters of the pelvis and hip joint in the frontal plane, there were nonsignificant coefficients of determination and poor ICCs with fixed and proportional biases.
The lower limb ROM in the sagittal plane during gait can be measured by the OpenPose-based motion analysis system. The markerless systems have the advantage of being more economical and convenient than conventional methods.
名为 OpenPose 的人体跟踪算法可以检测关节点并测量肢体和关节角度。然而，使用 OpenPose 进行步态分析的有效性尚未得到检验。
基于 OpenPose 的步态分析的有效性如何？
本研究纳入了 24 名健康的年轻人。参与者在行走和跑步时接受评估。使用 VICON 测量跑步机行走和跑步时骨盆节段角度以及髋关节、膝关节和踝关节角度。同时，使用数字相机从右侧和背面拍摄图像。OpenPose 处理后，从估计的关节点测量相应的角度。为了验证这些估计值，进行了线性回归分析，并计算了 OpenPose 和 VICON 获得的数据之间的组内相关系数[ICC（2,1）]。此外，通过 Bland-Altman 分析评估了 OpenPose 和 VICON 获得的数据之间的一致性。
在矢状面的大多数运动范围（ROM）中，髋关节、膝关节和踝关节的决定系数较大，没有比例偏差。在矢状面的大多数峰值角度中，膝关节和踝关节的决定系数较大，没有比例偏差，尽管髋关节的决定系数没有统计学意义且存在比例偏差。特别是在跑步时的髋关节屈伸 ROM 和峰值膝关节屈曲角度以及慢走时的膝关节 ROM 中，ICC 显示出良好到极好的一致性。然而，对于额状面的骨盆和髋关节参数，决定系数没有统计学意义，ICC 较差，存在固定和比例偏差。
基于 OpenPose 的运动分析系统可以测量步态中矢状面下肢的 ROM。无标记系统比传统方法更经济、更方便。
