Johansson Gudrun M, Grip Helena, Levin Mindy F, Häger Charlotte K
Department of Community Medicine and Rehabilitation; Physiotherapy, Umeå University, Building 15, SE-901 87, Umeå, Sweden.
School of Physical and Occupational Therapy McGill University, 3654 Promenade Sir William Osler, Montreal, Quebec, H3G 1Y5, Canada.
J Neuroeng Rehabil. 2017 Feb 10;14(1):11. doi: 10.1186/s12984-017-0220-7.
Upper limb coordination in persons post-stroke may be estimated by the commonly used Finger-to-Nose Test (FNT), which is also part of the Fugl-Meyer Assessment. The total movement time (TMT) is used as a clinical outcome measure, while kinematic evaluation also enables an objective quantification of movement quality and motor performance. Our aims were to kinematically characterize FNT performance in persons post-stroke and controls and to investigate the construct validity of the test in persons with varying levels of impairment post-stroke.
A three-dimensional motion capture system recorded body movements during performance of the FNT in 33 persons post-stroke who had mild or moderate upper limb motor impairments (Fugl-Meyer scores of 50-62 or 32-49, respectively), and 41 non-disabled controls. TMT and kinematic variables of the hand (pointing time, peak speed, time to peak speed, number of movement units, path ratio, and pointing accuracy), elbow/shoulder joints (range of motion, interjoint coordination), and scapular/trunk movement were calculated. Our analysis focused on the pointing phase (knee to nose movement of the FNT). Independent t or Mann-Whitney U tests and effect sizes were used to analyze group differences. Sub-group analyses based on movement time and stroke severity were performed. Within the stroke group, simple and multiple linear regression were used to identify relationships between TMT to kinematic variables.
The stroke group had significant slower TMT (mean difference 2.6 s, d = 1.33) than the control group, and six other kinematic variables showed significant group differences. At matched speeds, the stroke group had lower accuracy and excessive scapular and trunk movements compared to controls. Pointing time and elbow flexion during the pointing phase were most related to stroke severity. For the stroke group, the number of movement units during the pointing phase showed the strongest association with the TMT, and explained 60% of the TMT variance.
The timed FNT discriminates between persons with mild and moderate upper limb impairments. However, kinematic analysis to address construct validity highlights differences in pointing movement post-stroke that are not captured in the timed FNT.
中风后患者的上肢协调性可用常用的指鼻试验（FNT）进行评估，该试验也是Fugl - Meyer评估的一部分。总运动时间（TMT）用作临床结局指标，而运动学评估还能对运动质量和运动表现进行客观量化。我们的目的是对中风后患者和对照组的FNT表现进行运动学特征分析，并研究该试验在不同程度中风后损伤患者中的结构效度。
一个三维运动捕捉系统记录了33例中风后有轻度或中度上肢运动障碍（Fugl - Meyer评分分别为50 - 62或32 - 49）的患者以及41名非残疾对照组在进行指鼻试验时的身体运动。计算了手的TMT和运动学变量（指向时间、峰值速度、达到峰值速度的时间、运动单元数量、路径比和指向准确性）、肘/肩关节（运动范围、关节间协调性）以及肩胛骨/躯干运动。我们的分析集中在指向阶段（指鼻试验中从膝盖到鼻子的运动）。采用独立t检验或Mann - Whitney U检验以及效应量来分析组间差异。基于运动时间和中风严重程度进行亚组分析。在中风组内，使用简单和多元线性回归来确定TMT与运动学变量之间的关系。
中风组的TMT显著慢于对照组（平均差异2.6秒，d = 1.33），并且其他六个运动学变量也显示出显著的组间差异。在速度匹配时，与对照组相比，中风组的准确性较低，肩胛骨和躯干运动过多。指向阶段的指向时间和肘屈曲与中风严重程度最相关。对于中风组，指向阶段的运动单元数量与TMT的关联最强，解释了TMT方差的60%。
计时指鼻试验能够区分轻度和中度上肢损伤患者。然而，用于评估结构效度的运动学分析突出了中风后指向运动的差异，而这些差异在计时指鼻试验中未被捕捉到。
