de Jong L A F, Kerkum Y L, van Oorschot W, Keijsers N L W
Department of Research, Sint Maartenskliniek, Nijmegen, the Netherlands; Department of Rehabilitation, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands.
Research and Development, OIM Orthopedie, Assen, the Netherlands.
J Biomech. 2020 Jul 17;108:109895. doi: 10.1016/j.jbiomech.2020.109895. Epub 2020 Jun 13.
The Shank-to-Vertical Angle (SVA) is a commonly used parameter to describe orthotic alignment. 3D gait analysis (3DGA) or 2D video analysis are usually used to assess the SVA, but are not always feasible in clinical practice. As an alternative, an Inertial Measurement Unit (IMU) attached and aligned to the shank might be used. This study aimed to investigate the validity, inter-rater reliability and optimal location of a single IMU on the shank to assess the SVA. Thirteen healthy participants (7 m/6f, mean age: 45 ± 18 years) were recorded during quiet standing and barefoot walking using a 3D motion capture system and, simultaneously, with IMUs on the shank. The IMUs were anatomically placed and aligned at two different locations, i.e. anterior, in line with the tibial tuberosity and midline of the ankle (anterior IMU), and lateral, in line with the lateral epicondyle and lateral malleolus (lateral IMU). For each participant, the IMUs were placed by two different researchers. A paired t-test, Bland Altmann analysis (mean difference, repeatability coefficient) and intraclass correlation coefficient (ICC) between the 3DGA and both IMUs, and between raters, was performed. Although validity and reliability of the lateral IMU was low, good validity and inter-rater reliability was found for the anterior IMU (Rater1: mean difference: -0.7 ± 2.1, p = 0.27; ICC = 0.83 and Rater2: mean difference: -0.4 ± 1.9, p = 0.46; ICC = 0.86). Hence, a single IMU placed at the anterior side of the shank is a valid and reliable method to assess the SVA during standing and walking in healthy adults.
小腿与垂直方向夹角（SVA）是描述矫形器对线的常用参数。通常使用三维步态分析（3DGA）或二维视频分析来评估SVA，但在临床实践中并非总是可行。作为一种替代方法，可以使用附着并与小腿对齐的惯性测量单元（IMU）。本研究旨在探讨单个IMU在小腿上评估SVA的有效性、评分者间信度和最佳位置。在安静站立和赤脚行走期间，使用三维运动捕捉系统记录了13名健康参与者（7名男性/6名女性，平均年龄：45±18岁），同时在小腿上使用IMU进行记录。IMU在解剖学位置上放置并对齐在两个不同位置，即前侧，与胫骨结节和踝关节中线对齐（前侧IMU），以及外侧，与外上髁和外踝对齐（外侧IMU）。对于每位参与者，由两名不同的研究人员放置IMU。对3DGA与两个IMU之间以及评分者之间进行配对t检验、Bland Altmann分析（平均差异、重复性系数）和组内相关系数（ICC）分析。尽管外侧IMU的有效性和信度较低，但前侧IMU具有良好的有效性和评分者间信度（评分者1：平均差异：-0.7±2.1，p = 0.27；ICC = 0.83；评分者2：平均差异：-0.4±1.9，p = 0.46；ICC = 0.86）。因此，在健康成年人站立和行走期间，将单个IMU放置在小腿前侧是评估SVA的一种有效且可靠的方法。
