偏瘫患者下台阶过程下肢生物力学特征分析

目的 对比分析偏瘫患者以不同方式下台阶过程中下肢生物力学特征,为降低患者下台阶过程中的跌倒风险提供理论依据。方法 选取10名正常人和20名符合要求的偏瘫患者,使用Qualisys动作捕捉系统和Kistler三维测力台对受试者下台阶过程中的运动学和动力学数据进行收集,分析其在下台阶过程中的生物力学特征和跌倒风险。结果 相较于正常人和先用健足下台阶(steps on the healthy side, SHS),先用患足下台阶(steps on the affected side, SAS)时,患侧下肢各关节屈伸活动幅度较小;SHS降低了健侧膝关节屈伸活动幅度,患侧下肢各关节屈伸活动幅度较SAS大;SAS下台阶左右方向地面反作用力(ground reaction force, GRF)曲线变化与正常人较为一致,患侧落地瞬间垂直GRF最大为1.05倍体重,健侧为1.25倍体重,低于正常人(1.5倍体重);SHS下台阶健侧落地瞬间最大垂直GRF为1.85倍体重,高于SAS和正常人。结论 相较于SAS,患者使用SHS下台阶患侧关节活动幅度和落地瞬间垂直GRF较大,更难掌握。SAS更符合偏瘫患者下...     

痉挛型脑瘫儿童步态运动学特征

目的基于步态分析方法研究痉挛型脑瘫儿童行走的运动学特征。方法应用便携式步态分析仪对16例痉挛型脑瘫儿童和16例健康儿童平地常速来回行走的步态进行测试,比较痉挛型脑瘫儿童患侧与健侧、痉挛型脑瘫儿童与健康儿童的步态差异。结果与健侧相比,痉挛型脑瘫儿童患侧单步时间、摆动时间和跖骨离地期显著长于健侧(P 0. 05),患侧步频、步速、支撑相末期显著低于健侧(P 0. 05)。痉挛型脑瘫儿童患侧步态周期时间、单步时间、站立时间、摆动时间、站立相所占百分比、支撑相中期、摆动前期和跖骨离地期相比于正常儿童均显著增加(P 0. 05)。痉挛型脑瘫儿童跨步长、步速、步频、支撑相末期相比于正常儿童均显著降低(P 0. 05),拔腿强度也降低(P=0. 05)。结论痉挛型脑瘫儿童行走时稳定性降低,其患侧单步时间、摆动时间、跖骨离地期和拔腿强度或许可以作为敏感指标应用于临床评估,指导脑瘫儿童的康复治疗。     

坐骨神经痛患者的步态特征

目的分析总结坐骨神经痛患者的步态特征,辅助临床的诊断评估。方法连续住院治疗的43例伴有坐骨神经痛的腰椎间盘突出症患者,佩戴便携式步态分析仪后自由下平地行走120 m,同时纳入性别、年龄、身体质量指数(body mass index,BMI)匹配的43例健康受试者作为对照组。采集受试者的步态数据,包括7个时空参数(单支撑时间、双支撑时间、单双腿支撑时间比、步态周期时间、步速、步频、步长)以及4个加速度参数(拔腿强度、摆腿强度、地面冲击、足落地控制),对比患者与正常人、患者患侧与健侧下肢之间的步态差异。结果患者单支撑时间、单双腿支撑时间比、步速、步频、步长及4个加速度参数明显小于正常人,而双支撑时间延长。相比于患者健侧下肢,患侧下肢支撑时间、步频及4个加速度参数显著性减小,步长增加。结论坐骨神经痛患者患侧下肢运动功能出现障碍,影响步行能力。便携式步态分析仪可反映坐骨神经痛患者下肢的异常步态特征,为临床诊断评估提供参考。     

用便携式步态分析仪评估全髋关节置换术手术效果

目的通过比较全髋关节置换(total hip arthroplasty,THA)病人手术前后的步态变化,评估THA手术和康复效果。方法应用IDEEA便携式步态分析仪(Mini Sun公司,美国)测试7例THA患者手术前以及手术后25周自然行走时的步态,获得单腿支撑(single leg support,SLS)和双腿支撑(double-leg support,DLS)时间、SLS/DLS、跨步长、落腿强度等步态参数,并采用SPSS 16.0和Excel 2010对数据进行统计学分析。结果 THA患者术后健侧腿SLS比术前明显下降(P0.05);半数以上THA患者患侧腿SLS术后比术前降低,健侧腿DLS、SLS/DLS术后比术前明显下降,患侧腿术后落腿强度比术前增加。结论健侧腿SLS可作为评估THA手术效果的一个敏感性指标。应用便携式步态分析系统定量反映受试者的步态,是一种无创、可方便用于临床评估手术效果的方法。     

正常成人步态与偏瘫步态的比较与分析

本文首先介绍了步态分析的基本概念，正常步态与偏瘫步态进行的比较分析在临床上具有重要意义。步态分析系统对正常受试者和偏瘫患者进行检测。给出了人体下肢关节，地面反作用力等参数的测试结果，并对下沉成人与偏瘫患者的测试结果进行比较和分析，得出了初步结论。     

基于便携式步态测试仪的不同接受腔单侧大腿截肢者行走特点研究

目的 探讨穿戴坐骨包容接受腔与四边形接受腔大腿假肢的单侧大腿截肢者在日常生活中行走时的步态差异，为临床制定大腿假肢使用处方提供指导。方法 选取7位大腿截肢患者作为试验组，为患者分别适配四边形和坐骨包容接受腔大腿假肢。同时选取7位年龄、性别、身高和体质量相匹配的健康受试者作为对照组。所有受试者以舒适的步速在室外平路上行走240 m,应用便携式步态测试仪(intelligent device for energy expenditure and activity, IDEEA)采集步态数据，包括7个时空参数和4个加速度参数，通过IBM SPSS Statistics 23对数据进行处理。对比患者穿戴两种假肢与健康受试者之间、患者分别穿戴同种假肢时患侧与健侧之间、患者穿戴两种假肢时患侧之间、健侧之间的参数差异。结果 与健康受试者相比，患者分别穿戴两种假肢行走时，两种假肢健侧和患侧的站立时间和步态周期增大(P<0.05),步速、步频、跨步长减小(P<0.05);两种假肢患侧的摆动时间延长(P<0.05),地面冲击和足落地控制减小(P<0.05);四边形接受腔假肢双侧和坐...     

男性青年踝关节外侧副韧带损伤后行走步态分析

目的 获取青年男性踝关节外侧韧带损伤者行走时踝关节的运动学和动力学参数,探讨损伤者行走步态的生物力学特性。方法 采用Qualisys MCU500三维运动影像捕捉系统与Kistler三维测力台,对踝关节外侧副韧带损伤者与健康者各15名的行走步态进行三维同步测试。结果 踝关节外侧副韧带损伤者竖直方向的地面反力变化平缓;在支撑时相中前期,损伤者前后方向的力要比健康者大;在步态周期的60%之前,损伤者左右方向的力明显大于健康者。损伤者关节跖屈力矩变化与健康者相似,患侧外翻力矩、外旋力矩最大,损伤者健侧输出功率最大。结论 损伤者踝关节的稳定性下降,行走时步态异常,为减少患侧负荷,健侧出现代偿效应,足着地瞬间加速过度到垂直支撑时相。本研究为预防踝关节以及损伤后的临床治疗以及康复训练等提供一定的理论参考。     

10 m自由步行偏瘫步态胫前后肌群的表面肌电图研究

目的:利用表面肌电图(SEMG),分析偏瘫患者10 m自由步行胫前后肌群的SEMG变化规律,为拓展SEMG的临床应用建立可靠的依据。方法:2名偏瘫患者分别进行10 m自由步行测试,同步记录双下肢胫前肌、腓肠肌内侧头两组肌群的SEMG信号,考察受试肌在步态周期中的SEMG变化规律。结果:偏瘫步态的患侧腓肠肌与胫前肌同步收缩。患侧腓肠肌在迈步期有许多小波存在。患侧肌群的总体波幅显著小于健侧。结论:偏瘫步态的SEMG主要为患侧腓肠肌与患侧胫前肌的正常拮抗收缩状态减弱或丧失,以及患侧腓肠肌过度活跃,同时伴有患侧胫前肌的肌电活动减弱。     

偏瘫患者步态特征的动力学仿真分析

目的研究偏瘫步态特征与下肢异常肌力之间的内在关系,阐明导致偏瘫步态的肌力原因并为临床治疗提供建议。方法以偏瘫步态和正常步态为研究对象进行建模仿真,通过正常步态下仿真模型与实测数据对比验证模型有效性,对两种模型的运动学数据、地面反作用力(ground reaction force,GRF)及肌力等特征曲线进行差异分析。结果 LifeMOD仿真结果与测力台实测GRF曲线复相关系数为0.922,动力学模型合理有效。偏瘫步态患者初始着地期胫前肌肌力小导致踝关节背屈不足,摆动前期腓肠肌肌力小,起不到蹬离推动作用。结论胫前肌、腓肠肌软弱无力是偏瘫患者出现足下垂等偏瘫步态特征的主要原因,LifeMOD建模仿真可协助诊断偏瘫患者的异常肌力。     

一种跟随人体重心高度的骨盆支撑减重康复系统EI北大核心CSCD

支撑减重康复训练系统现已成为下肢运动功能障碍康复的重要治疗方法。本文针对现有的恒定阻抗减重的骨盆支撑减重康复系统在康复训练过程中骨盆机构提供固定的运动轨迹、患者主动参与康复训练程度低等问题,提出了一种跟随人体重心高度(CoMH)的骨盆支撑减重康复系统。该系统通过惯性测量单元采集人体下肢运动信息,经过人工神经网络对CoMH进行预测,实现骨盆支架高度的跟踪控制。通过偏瘫患者康复训练进行试验,结果表明,相比于骨盆支架运动轨迹固定的传统减重康复训练,跟随CoMH骨盆支撑减重康复训练使患者患侧髋、膝关节活动范围分别提升25.0%和31.4%,患侧摆动相与支撑相占比更接近健侧步态相位。该减重康复训练模式的骨盆支架的运动轨迹取决于当前训练者的状态,可实现偏瘫患者健侧主动运动引导行走训练。动态调整减重支撑的策略更有助于提高行走康复训练效率。     

双任务介入对社区脑卒中患者步态参数及其对称性的影响

目的 对比社区脑卒中患者单任务步行与不同类型和不同负荷双任务步行时步态参数及其对称性的差异。方法 利用 Simi Motion 三维动作分析系统采集 20 名处于慢性恢复期的社区脑卒中患者在单任务步行及不同负荷认知双任务步行和运动双任务步行时步态参数,并间接计算出其对称指数。 采用单因素重复测量方差分析对比单任务步行与不同双任务步行时步态参数及其对称性差异。 结果 与单任务步行相比,社区脑卒中患者在高低负荷认知任务介入时步速、患侧步长、健侧摆动相占比均降低,困难认知任务介入时健侧步宽和健侧、患侧支撑相占增加、健侧步长和患侧摆动相占比降低,摆动相占比对称指数减小(P<0. 05)。 结论 社区脑卒中患者主要通过降低步速、缩减步长、降低摆动相占比、增加步宽和支撑相占比,改变步态模式来应对认知任务干扰,对于步态稳定性,高负荷认知任务的介入,会增加社区脑卒中患者摆动相占比的不对称性程度,降低其步态稳定性。     

Body up-down acceleration in kinematic gait analysis in comparison with the vertical ground reaction force

In order to investigate clinical significance of the body up-down acceleration, and to practically verify the relationship with the vertical component of the ground reaction force, 3D kinematic gait analysis was performed on normal subjects and hip patients. The displacement of the body up-down movement was measured at the lower end of the sternum, then the acceleration was calculated from the displacement by using the double differential operation, and differential noise was removed by Finite Impulse Response (FIR) digital filter with the cutoff frequency of 3 Hz. The acceleration showed a regular cyclic pattern in normal subjects. However, in hip patients, there was a significant decrease of downward acceleration at the mid-stance of the affected side. And the acceleration was roughly consistent with the vertical component showing the same trends of up and down. However, in detail, they are inconsistent in the affected side, which is probably due to abnormal movements of the body and upper limbs, the so-called compensational movements.     

正走和倒走的膝关节生物力学特征比较

目的 比较正走和倒走两种不同行走模式时膝关节的生物力学特征。方法 采用三维运动捕捉系统Vicon T40和测力台AMTI OR6-7采集并比较13名健康青年男性志愿者正走和倒走时的时间、空间、运动学和动力学参数。结果 与正走相比,倒走时的步速、步频和步幅均显著减小,跨步周期和支撑相所占百分比显著增加;在矢状面上,倒走时膝关节活动度、最大屈伸力矩较正走小;在冠状面上,倒走时膝关节内翻外展活动范围也较正走小,内翻力矩峰值在支撑早期较正走小,但在支撑晚期较正走大;地面反作用力在支撑早期较正走大,但在支撑晚期较正走小。结论 倒走和正走膝关节生物力学特征差异明显。与正走相比倒走在支撑相早期能减轻膝关节内侧间室的负荷,而倒走在支撑相晚期对膝关节负荷的影响则尚须进一步研究。     

Step characteristics during obstacle avoidance in hemiplegic stroke

Whereas several animal studies have indicated the important role of the motor cortex in the control of voluntary gait modifications, little is known about the effects of cortical lesions on gait adaptability in humans. Obstacle avoidance tasks provide an adequate paradigm to study the adaptability of the stepping pattern under controlled, experimental conditions. In the present study, an exploratory assessment was made of the failure rate, the preferred stepping strategies (step lengthening vs step shortening), and the spatiotemporal stride characteristics (percentage increases in stride length, duration, and velocity of the crossing and postcrossing strides) during obstacle avoidance in 11 hemiplegic stroke patients and seven healthy controls. Patients were less successful in avoiding obstacles than controls (14% failure rate vs 0.5% in controls), independent of whether the affected or the unaffected leg led the obstacle avoidance. The number of failed trials increased systematically when the available response time became shorter. During successful trials, lengthening of the step was generally preferred over shortening. This bias towards step lengthening was more pronounced in stroke patients (step lengthening in 91% of the trials vs 75% in controls), irrespective of the side of obstacle presentation. For both groups, overall strategy preference did not adhere to a principle of minimal foot displacement, since step lengthening was used even if it would be more spatially efficient to shorten the step. No statistically significant group differences were found for the increases in length, duration, and velocity of the crossing and postcrossing strides. However, for a subgroup of more slowly walking patients, large percentage increases were found in crossing stride length, duration, and velocity. Similar results were obtained for the postcrossing stride, indicating that, for this subgroup of patients, restoration of the normal walking cadence was more difficult. Overall, no systematic differences were found between the affected and the unaffected leg in stroke patients with respect to failure rates, stepping strategies, or spatiotemporal measures of obstacle avoidance. The present findings suggest that the ability to adequately modify the stepping pattern in response to imposed spatiotemporal constraints is impaired in persons with stroke, especially when modifications have to be performed under time pressure. In addition, the stepping strategies employed by subjects with stroke are different from those found in controls, possibly to reduce the complexity of the avoidance maneuver and to enhance safety. Finally, unilateral cortical damage results in an impaired ability to avoid obstacles on both sides of the body, suggesting that the reduced ability of stroke patients to negotiate obstacles may be related to problems of a more general coordinative nature.     

基于鞋垫传感器测量垂直地面反作用力的算法

目的 提出一种实用、高精度的足底压力动态监测算法,通过电容式鞋垫传感器测量走路时垂直地面反作用力(vertical ground reaction force, vGRF),并验证预测精度的可靠性。方法 4名健康男性受试者穿戴电容式鞋垫传感器,在Kistler三维测力台上采集快速和慢速行走数据。对电容式鞋垫传感器采集到的数据进行像素化处理,处理后的数据输入残差神经网络ResNet18,预测得到高精度vGRF。结果 与Kister测力台收集的数据分析比较,快速和慢速行走的归一化均方根误差(normalized root mean square error, NRMSE)分别为8.40%和6.54%,皮尔森相关系数(Pearson correlation coefficient)均大于0.96。结论 本研究为移动场景下GRF动态测量提供了一种新型算法,可以用于实验室外完整GRF估计,而不受测力台数量和位置的约束,潜在应用领域包括步态分析以及有效捕捉病理性步态。     

Asymmetric bipedal locomotion – an adaptive response to incomplete spinal injury in the chick

The purpose of this study was to compare the asymmetric gait induced by unilateral spinal cord injury in chicks with asymmetric gaits of other bipeds and quadrupeds. After lateral hemisection of the left thoracic spinal cord, kinetic (ground reaction forces) and kinematic (distance and timing) data were recorded as chicks moved overground unrestrained. Ground reaction forces were analyzed to obtain the mechanical energy changes throughout the stride. Kinematic measurements were obtained over a range of speeds to determine the velocity-dependent characteristics of the gait. Hemisected chicks adopted an asymmetric hopping gait in which the animals hopped from the right leg (contralateral to the lesion) onto the left (ipsilateral) leg but then fell forward onto the right leg. Mechanical energy fluctuations throughout a single stride (i.e., two steps) approximated the oscillations that occur during a single walking step of control animals. When examined over a range of velocities, asymmetries in limb timing remained constant, but distance measurements such as step length became more symmetric as speed increased.The results show that, after spinal hemisection, adaptations of the remaining neural circuitry permitted the production of a locomotor pattern that, in addition to providing effective support and propulsion, incorporated some of the energy-conserving mechanisms of the normal walk. Adjustment of this novel locomotor pattern for different velocities further demonstrates the flexibility of locomotor circuitry. Comparisons with other studies shows that this gait shares some temporal and energetic features with asymmetric gaits of several bipedal species, including humans. In particular, hemisected chicks and some hemiplegic humans adopt an asymmetric gait in which maximum energy recovery occurs during the stance of the affected limb; these similarities probably relate to common mechanical constraints imposed on bipedal forms of terrestrial locomotion. Received: 18 November 1997 / Accepted: 30 April 1998