Sports Research Centre, Department of Sport Sciences, Miguel Hernandez University of Elche, Alicante, Spain.
Department of Biomedical Sciences, University of Sassari, Italy.
Phys Ther. 2021 May 4;101(5). doi: 10.1093/ptj/pzab049.
Research on muscle performance testing reliability in people with multiple sclerosis (MS) has focused on limb performance while less is known about trunk strength and endurance. This work aims to 1) establish test-retest reliability of trunk flexion, lateral flexion, and extension strength tests, and plank, side bridge, and Biering-Sørensen endurance tests in people with MS and matched healthy controls (HCs); 2) analyze known-groups validity of these tests in people with MS and HCs; 3) to compare groups for side-to-side differences; and 4) to describe the relationships between trunk performance and functional mobility tests.
Fifteen people with MS (median Expanded Disability Status Scale = 3) and 15 HCs underwent 2 trunk isometric strength and endurance testing sessions. Mobility was evaluated by Timed Up-and-Go test. Intraclass correlation coefficient, SEM, and minimal detectable change (MDC) were calculated. Between-group differences in trunk performance were tested using the t test for independent measures. Between-group differences in an asymmetry index were analyzed by independent t test. Bivariate correlations between trunk tests and mobility were also examined.
All trunk tests showed good-to-excellent relative reliability in both groups (intraclass correlation coefficient > 0.71). Regarding absolute reliability, strength tests were associated with low intersession variability in both groups (MDC: MS, 11.23%-36.45%; HCs, 26.60%-31.98%). Conversely, endurance tests showed higher variability scores in people with MS (MDC: MS, 69.55%-116.50%; HCs, 29.57%-54.40%). People with MS displayed significantly lower trunk performance. Likewise, the asymmetry index showed significantly higher scores in people with MS for endurance assessment but not in strength tests. Significant correlations were detected in people with MS between Timed Up-and-Go and several trunk tests (r = 0.63-0.70).
SEM and MDC scores revealed similar consistency and variability between groups for strength tests, whereas higher variability was observed for endurance tests in people with MS. Trunk strength tests are reliable and present discriminant validity to distinguish mildly disabled people with MS from HCs. Conversely, the high measurement error and variability of the endurance tests may hinder their application in intervention programs.
Determining the reliability and validity of the tests currently used to assess trunk function is of the greatest importance for people with MS (who show not only impaired trunk function but also wide fluctuations in performance), as it requires consistent and accurate measurements that are sensitive enough to detect minimal changes induced by rehabilitation.
多发性硬化症（MS）患者肌肉性能测试的研究主要集中在四肢表现上，而对躯干强度和耐力的研究则较少。本研究旨在：1）确定 MS 患者和匹配的健康对照组（HCs）躯干屈伸、侧屈和伸展力量测试以及平板支撑、侧桥和 Biering-Sørensen 耐力测试的测试-再测试可靠性；2）分析这些测试在 MS 患者和 HCs 中的已知组有效性；3）比较组间的侧间差异；4）描述躯干性能与功能性移动测试之间的关系。
15 名 MS 患者（中位扩展残疾状况量表[EDSS]为 3）和 15 名 HCs 接受了 2 次躯干等长强度和耐力测试。通过计时起立行走测试评估移动能力。计算了组内相关系数、标准误（SEM）和最小可检测变化（MDC）。使用独立样本 t 检验比较组间差异。通过独立 t 检验分析不对称指数的组间差异。还检查了躯干测试与移动能力之间的双变量相关性。
所有躯干测试在两组中均表现出良好至优秀的相对可靠性（组内相关系数>0.71）。关于绝对可靠性，两组的强度测试与较低的测试间变异性相关（MDC：MS，11.23%-36.45%；HCs，26.60%-31.98%）。相比之下，耐力测试在 MS 患者中显示出更高的变异性得分（MDC：MS，69.55%-116.50%；HCs，29.57%-54.40%）。MS 患者的躯干表现明显较低。同样，耐力评估中 MS 患者的不对称指数显示出更高的分数，但在强度测试中则不然。在 MS 患者中，Timed Up-and-Go 与多项躯干测试之间存在显著相关性（r=0.63-0.70）。
SEM 和 MDC 分数显示出两组之间的一致性和变异性相似，而 MS 患者的耐力测试的变异性更高。躯干强度测试可靠，具有区分轻度残疾 MS 患者和 HCs 的有效性。相比之下，耐力测试的高测量误差和变异性可能会阻碍其在干预计划中的应用。
确定目前用于评估躯干功能的测试的可靠性和有效性对 MS 患者（他们不仅表现出躯干功能受损，而且表现出表现波动较大）非常重要，因为它需要一致且准确的测量，并且足够敏感以检测康复引起的最小变化。
