基于膝关节支撑的两自由度人体坐立转换辅具的设计和运动轨迹控制

目的:研究一种两自由度坐立转换辅助装置的设计和轨迹控制方法.方法:对20名受试者分组进行坐立转换实验,分析受试者在不同坐立转换阶段的运动轨迹及运动学特征参数.结果:给出了 3组不同百分位和不同性别的人体的推荐坐立转换轨迹;提出了坐立转换辅具的设计方案,并设计了一款基于膝关节支撑的两自由度人体坐立转换辅具;建立机电控制系...     

膝骨关节炎患者步态中膝关节三维运动特征

目的:观察中老年膝关节骨关节炎(KOA)患者步态中膝关节的三维运动特征,为膝关节骨关节炎患者设计康复训练提供研究依据.方法:纳入符合标准的KOA患者29例为观察组;15例无KOA者纳入对照组.2组的年龄、身高、体重和身体质量指数(BMI)相匹配.2组受试者均使用KneeKG系统进行测量,对比自重状态下步行时两组受试者膝...     

脑卒中偏瘫患者上肢运动功能障碍的生物力学机制研究

目的 探讨脑卒中患者偏瘫侧上肢运动功能障碍的运动学及肌电学特征。 方法 选取39例脑卒中偏瘫患者和25例健康人分别纳入实验组和对照组。应用穿戴式微型传感器运动捕获系统和表面肌电技术采集受试者上肢前屈够物时的三维运动学数据和表面肌电信号,经处理后提取5个运动学参数,即躯干扭转度、肩关节活动度、运动速度、等张失稳度和等长失稳度,同时还对比分析肌电学特征,包括积分肌电值（iEMG）和肌肉做功比。将前屈够物过程分为前屈阶段和维持阶段,分别比较实验组和对照组在前屈阶段运动学参数和2个阶段的肌电参数,并分析实验组运动学参数与肌电参数间的相关性。 结果 ①实验组患侧躯干扭转度、等张失稳度和等长失稳度明显大于对照组,而肩关节活动度及运动速度均明显小于对照组,组间差异具有统计学意义（P<0.05）。②实验组在够物前屈阶段其偏瘫侧上肢斜方肌上部iEMG值明显大于对照组,而三角肌前束和肱三头肌iEMG值明显小于对照组,组间差异具有统计学意义（P<0.05）;三角肌中束和肱二头肌iEMG值组间差异无统计学意义（P>0.05）;三角肌前束/斜方肌上部做功比和三角肌前束/中束做功比均小于对照组,肱二头肌/肱三头肌做功比大于对照组,组间差异均具有统计学意义（P<0.05）。③够物维持阶段,实验组与对照组各肌肉iEMG值及肌肉做功比统计结果与前屈阶段一致。④躯干扭转度与斜方肌上部iEMG值呈正相关（r=0.359,P<0.05）;肩关节活动度与三角肌前束iEMG值呈正相关（r=0.366,P<0.05）;运动速度与三角肌前束iEMG值呈正相关（r=0.344,P<0.05）。 结论 脑卒中患者偏瘫侧上肢在够物过程中其运动学参数及表面肌电参数均出现异常特征性改变,上述指标可用于运动功能障碍定量评估及康复治疗指导。     

腰椎间盘突出症患者步态特征的研究

目的:利用三维步态分析系统定量分析腰椎间盘突出症患者的步行特征,为腰椎间盘突出症患者的临床诊疗、康复训练计划制定及康复疗效评定提供客观依据。方法:共纳入20例健康志愿者和20例腰椎间盘突出症(lumbar disc herniation,LDH)患者,并对20例患者进行Oswestry功能障碍指数(Oswestry disability index,ODI)评分、下腰痛JOA(Japanese Orthopaedic Association)评分及VAS(Visual Analogue Score)评分。利用三维步态分析系统采集所有受试者的运动学数据,即在受试者身体表面腰痛相关位点粘贴红外线标示点,共19处,受试者在平地上规定的路线内行走,要求受试者以舒适的速度行走5m以上的距离,共行走4次。采用SPSS 22.0软件对患者的量表评分及所有受试者的运动学数据进行统计学分析。结果:①腰椎间盘突出症患者组患侧肢体与健侧肢体比较发现:患肢的步长明显减小,步频明显加快;②腰椎间盘突出症患者患侧肢体与健康志愿者同侧肢体比较发现:患者患侧肢体的步长、跨步长、膝关节屈伸活动范围及髋关节前屈后伸活动范围明显减小;③腰椎间盘突出症患者健侧肢体与健康志愿者同侧肢体比较发现:患者健侧肢体的步长、跨步长、步频、膝关节屈伸活动范围及髋关节前屈后伸活动范围明显减小;④通过相关性分析发现:JOA、ODI、VAS评分与患者的步长、跨步长、髋关节前屈后伸活动范围有相关性(P0.05),与患者的步频、膝关节屈伸活动范围无明显相关(P0.05)。结论:腰椎间盘突出症患者受腰痛的影响,导致步长及跨步长减小,步频加快,膝关节屈伸活动范围及髋关节前屈后伸活动范围减小。     

基于人体坐立转换运动规律的三自由度站立康复机器人设计

目的:探究以何种方式设计站立康复辅具,降低因人机匹配度差导致的固化姿态形成几率。方法:选取30例成年健康男性受试者,捕捉其坐立转换时肩峰、大转子隆起处、外侧髂隆起处的运动轨迹和运动特征。提出了三自由度串联机械臂设计方案。结果:根据受试者的运动特征将坐立转换过程分成了四个阶段。根据不同受试者的人体参数,推荐了三条大转子轨迹,设计了三自由度站立康复机器人。结论:站立康复辅具应以大转子位置为辅助支撑点为佳,小腿的自由度不应被限制,配合控制躯干倾角,以保证与自然状态下的站立过程较高的相似度。站立康复辅具能够根据不同人体参数调整坐立转换的运动轨迹,避免人机融合性差导致错误的固化姿态。     

性别对正常人坐站转移过程髋关节运动学参数及足底压力的影响

目的:探究性别对坐站转移过程的髋关节运动学参数及足底压力的影响。方法:比较正常男性75名和女性76名在从坐到站过程中不同时期的运动学参数如髋关节角度变化、运动速度、时间等及足底压力变化如压力、压强、接触面积等,分别比较性别作为变量下的各个参数的差异。结果:①髋关节运动学参数:在坐站转移过程中的躯干前倾角度男性大于女性,差异有显著性意义(P<0.05),躯干前倾速度及在站起过程中的速度男性大于女性,差异有显著性意义(P<0.01)。②足底压力参数:在坐站转移的整个过程,男性的单位面积足底压力明显高于女性,差异有显著性意义(P<0.01);在转移末期女性的足-地间的接触面积增加明显大于男性,差异具有显著性意义(P<0.05)。结论:在无辅助下坐站转移时男性主要靠增加转移速度、女性依靠增加足-地间的接触面积来完成动作,这在制定相关疾病的个性化康复方案及为不同性别人群提供合理化健身指导性建议时是必须考虑的重要方面。     

足位变化对立位平衡的影响

<正> 本研究旨在证实足位变化对站立平衡的影响。对象与方法健康成人10名(男7,女3),年龄28.3±5.2岁,身高167.8±8.4 cm,体重61.9±15.5kg,全是右利手。采用Annima 公司的G6100重心计,取样周期20ms(50Hz)。在安静室内,受试者赤足站立,二眼平视牌上目标,保持20 s。以足跟为原点,足位变化14次。前额面4次:二足并拢及足长轴间矩15 cm、30 cm、40 cm。矢状面5次:以两足长轴相矩15 cm 为基础,二足跟并行及右足跟向前10cm、20cm 向后10cm、20cm。水平面5次:在二足间保持15cm 基础上,足长轴和矢状轴角度0,脚尖向内25°、45°,向外25°、45°测各足位X 轴方向,Y 轴方向的重心摆动矩离(X—LNG,Y—LNG)、重心摆     

简化太极拳运动中的位移和重心变化

目的探讨缓慢柔和动作在简化太极拳运动疗法中的作用。方法40名年龄、身高和体重相近的健康成年男性分为练拳组和步行组各20名。测练拳组练一遍太极拳的位移和步行组步行18m的耗时,另测1名练拳者运动中的身体重心变化。结果练拳组5min太极拳运动位移(1796.4±91)cm,步行组舒适步行18m耗时(14.1±1.7)s,练拳中身体重心下移(5.5±12.7)cm(t=1.223,P>0.05)。结论动作缓慢柔和构成太极拳运动疗法的运动学基础。     

大学生动静态平衡能力与形态指标的相关性研究

目的:分析人体形态学各指标与大学生平衡能力间的相关性,并以此为大学生平衡能力的提高提供依据。方法:对133名受试者进行动静态平衡能力及身高、体重、柔韧性等人体形态指标进行测试,对男女两组平衡能力进行T检验,对受试者的平衡能力与各指标进行pearson分析。结果:男女受试者的动静态平衡能力均无差异性(P>0.05),静态平衡测试值与柔韧性、全身反应时、背肌力、身高、体重、BMI指数、踝关节背屈活动度之间的相关系数均小于0.2,无相关性。动态平衡测试值与身高、体重、BMI均呈负相关,与柔韧性及踝关节背屈活动度之间成正相关。结论:大学生的动态平衡能力与柔韧性及踝关节的灵活程度密切相关,但该文所测各项数据与静态平衡能力均无关联。     

基于高频超声的正常未育女性腹直肌间距测量及其相关因素分析

目的应用高频超声测量正常未育女性腹直肌间距(IRD),同时分析其相关因素。方法选取我院行健康体检的106名正常未育女性志愿者,体质量指数(BMI)均≤30 kg/m2,应用高频超声分别于仰卧位静息状态及卷腹动作测量脐上3 cm、脐部、脐下2 cm和脐下3 cm 4个位置的IRD,应用百分位数法计算IRD范围;分析IRD与年龄、身高、体质量、BMI的关系。结果正常未育女性仰卧位静息状态IRD值为:脐上3 cm为4～15 mm,脐部为5～20 mm,脐下2 cm为0～7 mm,脐下3 cm为0～3 mm,与卷腹动作时各值比较差异均无统计学意义。相关性分析显示,IRD与年龄、身高无相关性,与体质量和BMI呈弱正相关(r=0.20、0.27,P=0.04、0.01)。结论应用高频超声可准确检测正常未育女性IRD值,且IRD与体质量和BMI均呈弱正相关。     

Kinematic analysis of sit to stand by persons with rheumatoid arthritis supported by a service dog

Purpose.?The objective of this study was to quantify the kinesiological effect of the assistance provided by service dogs on transferring from sit to stand in persons with rheumatoid arthritis (RA).

Methods.?Twenty-four participants performed a total of eight experimental transfers of sit to stand, including unassisted transfers, transfers with a cane and transfers with assistance from a service dog. We analysed movements at the lower extremity joints using a three-dimensional kinematics system and two force plates.

Results.?At the hip joints, the range of motion changes and energy expenditure with a cane and with the service dog were smaller than that of the unassisted transfers. Transfers with a service dog resulted in less joint movement and less energy used in movements at the knee and ankle joints; participants also scored themselves as requiring less effort on a self-rating scale than in the other conditions.

Conclusion.?A service dog provides benefits in assisting with transfers from sit to stand by persons with RA. Future studies should consider training the service dogs to assume correct positions and use appropriate timing to support their partners during these transfers.     

Informed consent: requirements for legal and ethical practice

More patients with bilateral joint problems are choosing to go through one surgery to replace both joints simultaneously rather than having two separate surgeries. The goals of physical therapy following the surgery are to decrease pain, maximize range of motion (ROM) and strength, improve ambulation, and improve overall function. Few studies have focused on the importance of the acute phase of rehabilitation and most concentrate instead on long-term outcomes and outpatient care. The patient was a 62-year-old male diagnosed with osteoarthritis of both knees. The day before the initial physical therapy evaluation, the patient underwent a bilateral total knee arthroplasty. By the end of his stay, active knee ROM increased to ?6° to 88° on the right and ?6° to 83° on the left. Passive ROM also increased to ?5° to 90° on the right and ?5° to 86° on the left. The patient was able to perform supine to sit transfers with supervision and sit to stand transfers with contact guard assistance and his ambulation progressed to walking 100 feet on level surfaces with a rolling walker and supervision. The positive gains of this patient suggest the potential value of high motivation combined with early aggressive physical therapy.     

Simulated leg-length discrepancy: its effect on mean center-of-pressure position and postural sway

We hypothesized that leg-length discrepancies of as little as 1cm would induce a significant postural shift and increase the extent of postural sway. We had 14 normal volunteers stand on a force platform with their feet in a standard position. Center-of-pressure data were recorded at 100Hz for 20 seconds while the subjects stood barefoot with no lifts or (in random order) with lifts of 1, 2, 3, and 4cm under their left and right feet. From these data we derived the mean center-of-pressure position and the extent of postural sway. Lifts of as little as 1cm shifted the mean center-of-pressure toward the longer leg to a statistically significant extent (p less than 0.001), the mean difference compared with the barefoot condition being 6.1% of the distance between the feet; increasing the discrepancy did not proportionately increase the effect. The postural sway (total travel of the center-of-pressure) in a mediolateral direction increased significantly with a 1cm discrepancy (p less than 0.01), and continued to increase in proportion to the magnitude of the discrepancy. There were no effects on anteroposterior position or sway and no influence of left-right dominance. These results support our hypothesis that a leg-length discrepancy of as little as 1cm may be biomechanically important.     

An acute care episode of a patient following bilateral total knee arthroplasty

More patients with bilateral joint problems are choosing to go through one surgery to replace both joints simultaneously rather than having two separate surgeries. The goals of physical therapy following the surgery are to decrease pain, maximize range of motion (ROM) and strength, improve ambulation, and improve overall function. Few studies have focused on the importance of the acute phase of rehabilitation and most concentrate instead on long-term outcomes and outpatient care. The patient was a 62-year-old male diagnosed with osteoarthritis of both knees. The day before the initial physical therapy evaluation, the patient underwent a bilateral total knee arthroplasty. By the end of his stay, active knee ROM increased to -6 degrees to 88 degrees on the right and -6 degrees to 83 degrees on the left. Passive ROM also increased to -5 degrees to 90 degrees on the right and -5 degrees to 86 degrees on the left. The patient was able to perform supine to sit transfers with supervision and sit to stand transfers with contact guard assistance and his ambulation progressed to wvalking 100 feet on level surfaces with a rolling walker and supervision. The positive gains of this patient suggest the potential value of high motivation combined with early aggressive physical therapy.     

Surgery simulation analysis of anterior advancement of the tibial tuberosity

The objective of this study is to evaluate the surgical outcome of anterior displacement of the tibial tuberosity (Maquet procedure) for reducing patellofemoral joint contact force. Thein-vivo experimental knee joint geometric data with a biomechanical model was used to do the simulation of the Maquet procedure. Six healthy young adults performed weight-bearing knee flexion-extension by ascending a one-step stair. Dynamic X-ray images of the knee were continuously recorded by a video-fluoroscopic system. These X-ray images were analysed on a computerized digitizing system to get the knee joint geometric data. Based on the continuous in-vivo geometric data, computer surgery simulation was studied on six right knees with advancement of 3, 5, 10, 15, and 20 degrees of the patellar tendon insertion. Evaluation of the simulation consequences from a biomechanical view point showed that the Maquet procedure reduced the patellofemoral joint reaction force only up to 20% at 90 degrees of knee flexion angle. The patellofemoral joint reaction force had 50% reduction only when the knee flexion angle less than 20 degrees, and only when the patellar tendon was moved out by 15 or 20 degrees. This represented nearly 1 in. of the anterior displacement of the tibial tuberosity. The results also showed that the Maquet procedure would decrease up to 20% of the force transmission efficiency of the patellofemoral mechanism, which would cause the mechanical consequences of the operation to be only minor at larger knee flexion angles more than 20 degrees. These findings suggest that the Maquet procedure is only favourable to less active or older patients having small knee flexion angle activities. RELEVANCE: Surgical procedure of anterior displacement of the tibial tuberosity has been used to reduce the patellofemoral joint contact force for treatment of symptomatic osteoarthrosis of the patellofemoral joint. In this study the patellofemoral joint reaction force had 50% reduction only when the knee flexion angle was less than 20 degrees, and only when patellar tendon was moved out nearly 1 in. Based on this result, the Maquet procedure is suggested only favourable to less active or older patients having small knee flexion angle activities.     

The effects of simulated knee-flexion contractures on standing balance

The effects of simulated unilateral and bilateral knee-flexion contractures on standing balance were studied by testing 15 normal subjects on a Kistler force platform. Postural sway (mediolateral and anteroposterior travel) and the mean position of the center of pressure (as a percentage of the distance between the midlines of the feet and from heels to toes) were determined from 20 s of data. Unilateral and bilateral knee-flexion contractures of 15 degrees and 30 degrees were simulated for each subject by means of an adjustable line from the subject's waist to the sole of each foot. Paired t tests were used to compare balance parameters while standing with the simulated contractures with those during relaxed standing. Mediolateral travel increased by a mean difference of 3.6 cm with a 30 degree unilateral contracture (P less than 0.01) and by 5.0 cm with 30 degrees bilateral contractures (P less than 0.01). Anteroposterior travel increased by 4.7 cm (P less than 0.05) and 8.8 cm (P = 0.08) with 15 degrees and 30 degrees bilateral contractures, respectively. With a unilateral contracture of 30 degrees, the center of pressure shifted 15.6% (P less than 0.0005) toward the unflexed side, changes that were not eliminated by correction of the induced leg-length discrepancy. The center of pressure moved anteriorly by 8.3% with 30 degrees bilateral contractures (P less than 0.001). The results provide insight into how knee-flexion contractures alter standing balance, and underline the importance of preventing and treating this common disorder.     

Differences in the movement pattern of a forward lunge in two types of anterior cruciate ligament deficient patients: copers and non-copers

OBJECTIVE: To determine whether differences in the knee joint movement pattern of a forward lunge could be quantified in healthy subjects and in anterior cruciate ligament deficient subjects who were able to return to the same activity level as before their injury (copers) and in those who were not (non-copers). DESIGN: The movement patterns of the injured leg of the coper and non-coper anterior cruciate ligament deficient subjects and the right leg of the control subjects were compared statistically. BACKGROUND: The forward lunge seems to be a less stressful test than the commonly used one-legged hop test, which makes it a possible tool for evaluating and comparing the functional performance of non-copers and copers. METHODS: The movement pattern of a forward lunge was analysed by using a two-dimensional inverse dynamics method. The electromyographic activity of the quadriceps and hamstring muscles were recorded. RESULTS: The non-copers moved more slowly and loaded the knee joint less than the copers and controls. The copers moved more slowly during the knee flexion phase but as fast as the controls during the knee extension. The EMG results suggest that the copers stabilized their knee joint by increasing the co-contraction of the hamstrings during the extension phase. CONCLUSIONS: Differences between the three groups' movement patterns could be quantified. The forward lunge test seems appropriate to discriminate between the knee function in coper and non-coper anterior cruciate ligament deficient subjects. RELEVANCE: Information about the performance of movements, which significantly load the knee joint in coper and non-coper anterior cruciate ligament deficient patients may contribute to a better understanding of dynamic knee joint stabilization, which is relevant in relation to the development of rehabilitation strategies.     

Some biomechanical characteristics of standing up at three different speeds: implications for functional training

Individuals with motor disability typically stand up (STS) more slowly than able-bodied subjects, and are at risk of falling. The purpose of this study was to examine the effects of varying movement speed on angular displacement and velocity of trunk flexion at the hips and on extensor force production through the lower limbs. Able-bodied subjects were videotaped as they stood up at three different speeds (fast, slow, preferred) with feet on a force plate. Amplitude of hip flexion was greater but velocity was less when subjects moved slowly compared with fast. Moving slowly was also characterized by a decrease in peak support moment, an increase in time spent sustaining an overall extensor force of three times body weight, and a reversal in sequencing of joint movement onsets. The force-time trade-offs and variations in the basic motor pattern associated with differences in speed suggest that training to increase muscle strength and intersegmental coordination in STS should involve practising standing up at a range of speeds since the ability to control speed variation is critical to independence.     

Differences of ground reaction forces and kinematics of lower extremity according to landing height between flat and normal feet

The study compared lower extremity kinematics and kinetics between male subjects with flat and normal feet when landing on both feet from platforms at different heights. Ten subjects with a flat feet arch and 10 subjects with a normal foot arch were recruited. They performed a double limb drop landing from 20, 40, and 60 cm onto a force-plate. A three-dimensional motion analysis system, force plates, and electromyography were used to analyze lower extremity kinetic and kinematic data. The GRF and angle of sagittal plane significantly increased with landing height in the flat foot group. In particular, hip joint angles at a height of 60 cm were significantly greater. The electromyography values were significantly higher for the tibialis anterior and vastus lateralis muscles, but were significantly lower in the abductor hallucis, gastrocnemius, and biceps femoris muscles in the flat foot group. GRF, joint angles, and muscle activity patterns in the lower extremities increases more with height in flat footed individuals than in people with a normal foot arch. Flat feet may aggravate the risk of shock on landing from a height; this might be ameliorated by a compensatory strategy at the hip joints to facilitate load distribution.