背景:走路时转头(日常生活中经常需要的动作)对于保持平衡特别具有挑战性。因此,它可以潜在地揭示患有多发性硬化症的早期患者的细微损伤,这些患者仍然表现出正常的运动(NW-PwMS)。这将有助于确定那些可以从旨在减缓MS相关功能下降的早期预防性运动中受益的受试者。
目的:分析通过惯性传感器对水平头转弯行走(WHHT)的评估是否可以区分健康受试者(HS)和NW-PwMS以及NW-PwMS亚组。评估仪器化WHHT的判别能力是否高于临床评分。评估基于传感器的度量的并发有效性。
方法:在这项多中心研究中,测试了40HS和59NW-PwMS[扩展残疾状态量表(EDSS)≤2.5,疾病持续时间≤5年]。参与者在躯干和脚踝上佩戴三个惯性传感器,执行了富勒顿高级平衡秤(FAB-s)的第6项。行走时以节拍器的节拍(100bpm)水平转动头部所需的物品。传感器的信号被处理以计算时空,规律性,对称性,动态稳定性,和描述WHHT的树干摇摆度量。
结果:中外侧规律性,前后对称,NW-PwMS与中外侧稳定性降低HS(p≤0.001),并显示出中等的判别能力(受试者操作员特征曲线下面积[AUC]:0.71-0.73)。在EDSS中,AP对称性和ML稳定性降低(p≤0.026):2-2.5与EDSS:0-1.5亚组(AUC:0.69-0.70)。NW-PwMS显示至少一个异常仪器度量(68%)的数量大于(p≤0.002)显示异常FAB-s-Item6(32%)和FAB-s临床评分(39%)的参与者数量。与EDSS:0-1.5亚组(57%)相比,EDSS:2-2.5亚组包括更多显示异常仪器指标的个体(86%)。测量指标与FAB-s-Item6和FAB-s得分显着相关(|Spearman\'srs|≥0.37,p<0.001),从而证明了它们的同时有效性。
结论:WHHT的仪器化评估提供了有效的客观指标,敏感性高于临床评分,HS和NW-PwMS之间以及EDSS亚群之间。该方法是补充临床评估的有前途的工具,并揭示可以从早期预防性康复干预中受益的人的亚临床损伤。
BACKGROUND: Turning the head while walking (an action often required during daily living) is particularly challenging to maintain balance. It can therefore potentially reveal subtle impairments in early-stage people with multiple sclerosis who still show normal locomotion (NW-PwMS). This would help in identifying those subjects who can benefit from early preventive exercise aimed at slowing the MS-related functional decline.
OBJECTIVE: To analyze if the assessment of walking with horizontal head turns (WHHT) through inertial sensors can discriminate between healthy subjects (HS) and NW-PwMS and between NW-PwMS subgroups. To assess if the discriminant ability of the instrumented WHHT is higher compared to clinical scores. To assess the concurrent validity of the sensor-based metrics.
METHODS: In this multicenter study, 40 HS and 59 NW-PwMS [Expanded Disability Status Scale (EDSS) ≤ 2.5, disease duration ≤ 5 years] were tested. Participants executed Item-6 of the Fullerton Advanced Balance scale-short (FAB-s) wearing three inertial sensors on the trunk and ankles. The item required to horizontally turn the head at a beat of the metronome (100 bpm) while walking. Signals of the sensors were processed to compute spatiotemporal, regularity, symmetry, dynamic stability, and trunk sway metrics descriptive of WHHT.
RESULTS: Mediolateral regularity, anteroposterior symmetry, and mediolateral stability were reduced in NW-PwMS vs. HS (p ≤ 0.001), and showed moderate discriminant ability (area under the receiver operator characteristic curve [AUC]: 0.71-0.73). AP symmetry and ML stability were reduced (p ≤ 0.026) in EDSS: 2-2.5 vs. EDSS: 0-1.5 subgroup (AUC: 0.69-0.70). The number of NW-PwMS showing at least one abnormal instrumented metric (68%) was larger (p ≤ 0.002) than the number of participants showing abnormal FAB-s-Item6 (32%) and FAB-s clinical scores (39%). EDSS: 2-2.5 subgroup included more individuals showing abnormal instrumented metrics (86%) compared to EDSS: 0-1.5 subgroup (57%). The instrumented metrics significantly correlated with FAB-s-Item6 and FAB-s scores (|Spearman\'s r s | ≥ 0.37, p < 0.001), thus demonstrating their concurrent validity.
CONCLUSIONS: The instrumented assessment of WHHT provided valid objective metrics that discriminated, with higher sensitivity than clinical scores, between HS and NW-PwMS and between EDSS subgroups. The method is a promising tool to complement clinical evaluation, and reveal subclinical impairments in persons who can benefit from early preventive rehabilitative interventions.