脑卒中偏瘫患者上肢运动功能的生物力学机制研究

Stroke is one of the leading causes of disability in adults worldwide. The hemiparesis is a common sequelae which affects survivors' daily living. Currently, the functional recovery rate of upper extremity (UE) is as low as <15%. The one of main reasons is that the mechanism of UE functional movement such as reaching is not well established due to the limitations in methodology...This study is proposed by Rehabilitation Medicine Department of Peking University First Hospital, collaborating with Sensor Networks and Applications Joint Research Center, Graduate School of Chinese Academy of Sciences, which has developed world class wearable micro-sensor motion capture system, supported by a NSFC major project, and simultaneous surface electromyography (sEMG). By using the new technologies, the applicants have completed a series of preliminary studies to investigate the biomechanics of reaching movement, including 1) establishment of the hardware and software system for capture and analysis of the signals from UE kinematics and sEMG; 2) proposed and tested a set of novel quantitative measures, referred to as Motor Feature Indices, which showed more effective reflection of the motor impairment compared with the semi-quantitative clinical measurement scale; 3) synchronization of sEMG signals of the related UE muscles during reaching. The experimental data showed that muscles activation order and muscles workload distribution were different between stroke patients and control subjects...We hypothesize that the muscles of paretic UE have saturation of their activation during reaching and require recruitment of other muscles due to either weakness or spasticity, resulting in abnormal compensatory movement patterns, and some muscle activation ratios, such as biceps/triceps, are critical predictors for functional recovery. By knowing these features, rehabilitation program will become more efficient. The objectives of this study are to explore the biomechanics in reaching performed by stroke patients, to develop quantitative measures and reveal critical muscle activation patterns, which could provide theoretical and practical guide in rehabilitation to improve the UE functional recovery...This study consists of three components: 1) to optimize the measure system of real time three-dimensional motion capture for multiple joints in UE during reaching and simultaneous sEMG signals of major muscle groups; 2) to derive critical biomechanical features which affect functional recovery of stroke patients for optimizing the rehabilitation and evaluating the prognosis; 3) to establish a quantitative measure system for developing a case database.. .This is the inter-disciplinary study between rehabilitation medicine and information science. The achievement of the proposed study will provide the critical information for a new quantitative categorization system in rehabilitation and result in new equipments developing to benefit more hemiparesis patients after stroke.

脑卒中是导致运动残疾的主要疾病，功能恢复主要依赖康复治疗。以生物力学为核心的运动再学习理论有效地指导了运动康复治疗方案的制定。但是，由于上肢生物力学特征复杂，目前相关研究未能揭示患者实际状态下上肢三维运动中多关节运动相关肌群间的协调水平及与运动实时同步对应的生物力学机制，致使上肢功能康复率较低。本课题拟在申请者前期相关研究和运动再学习方面研究积累的基础上，结合中科院研究生院研发的我国第一个人体运动捕获系统和同步阵列式高精度肌电采集和分析技术，突破方法学上的瓶颈，研究脑卒中患者上肢够物技能多关节三维运动相关肌肉状态及肌群间协调机制，揭示影响功能恢复的关键性生物力学特征，并建立数字化特征度量系统，为临床分析功能康复的关键性限制因素提供依据，更科学地优化治疗，动态定量监测疗效及判断预后，使运动再学习理论上升到数字化高度。研究成果将为建立新一代数字康复分类系统提供关键信息，使之更为广泛地惠及患者。

本项目旨在研究脑卒中患者上肢够物过程中的相关运动学和肌电特征，揭示异常运动模式机制及影响功能的关键性生物力学特征，以期建立数字化特征度量系统，为功能康复提供依据。. 研究中对脑卒中患者和健康人在上肢前屈够物的三维动态过程中，应用自主研发的运动捕获系统和表面肌电仪对多关节的运动信息和相关肌群的表面肌电信号进行了同步采集，并通过数学建模筛选和分析，形成了特征性参数。运动学参数主要包括：最大运动角度、角度分散度、运动平均速度、躯干扭转度及速度熵。表面肌电采用时域分析了肌肉做功分布及肌群间做功比，并通过非负性矩阵分解计算的方法得到了肌肉协同（Muscle Synergies）的特征性变量。结果发现患者的特征性参数均与健康人有显著性差异，且与临床评测Fugl-meyer量表有显著相关性。运动学参数定量反映了患者对运动轨迹的控制能力减弱，且出现躯干代偿，所代表的运动质量差异客观量化地反映了患者功能障碍的严重程度。肌电信号分析发现患者三角肌前组/斜方肌做功比显著低于健康人，需要斜方肌共同做功来完成前屈动作，且肌电特征与运动学间存在显著对应关系。这表明临床所见的偏瘫患者的运动表现可能是由于主缩肌力弱而出现的代偿性异常运动模式。对肱二头肌/肱三头肌做功比的分析表明，尽管患侧上肢主动伸肘时做功比出现变小的拐点，但整体显著高于健康人，说明屈曲协同模式的持续存在。由此，本项目提出了肌肉协同的分析方法，它是为了解决上肢运动中多自由度问题而提出的诸多模型之一，直接反应中枢神经系统的运动控制变化。结果形成3个特征分量，病情越轻，其协同模式与正常对照越相似，呈保留模式，且与临床评估Fugl-meyer或Brunnstrom分期一直，能定量地直接反应中枢控制的变化。. 本项目研究结果为脑卒中偏瘫患者上肢异常功能提供了生物力学机制依据，提出了运动学、表面肌电和协同模式等一系列数字指标及其测量方法，为运动功能评估的数字化、智能化提供了关键技术，为康复治疗提供了指导性思路和制订方案的依据。