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1.
When walking at normal and fast speeds, humans swing their upper limbs in alternation, each upper limb swinging in phase with the contralateral lower limb. However, at slow and very slow speeds, the upper limbs swing forward and back in unison, at twice the stride frequency of the lower limbs. The change from “single swinging” (in alternation) to “double swinging” (in unison) occurs consistently at a certain stride frequency for agiven individual, though different individuals may change at different stride frequencies. To explain this change in the way we use our upper limbs and individual variations in the occurrence of the change, the upper limb is modelled as a compound pendulum. Based on the kinematic properties of pendulums, we hypothesize that the stride frequency at which the change from “single swinging” to “double swinging” occurs will be at or slightly below the natural pendular frequency (NPF) of the upper limbs. Twenty-seven subjects were measured and then filmed while walking at various speeds. The mathematically derived NPF of each subject's upper limbs was compared to the stride frequency at which the subject changed from “single swinging” to “double swinging.” The results of the study conform very closely to the hypothesis, even when the NPF is artificially altered by adding weights to the subjects' hands. These results indicate that the pendulum model of the upper limb will be useful in further investigations of the function of the upper limbs in human walking. © 1994 Wiley-Liss, Inc.  相似文献   

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A mathematical model of Ihe human upper limb was developed based on high-resolution medical images of the muscles and bones obtained from the Visible Human Male ( HM) project. Three-dimensional surfaces of the muscles and bones were reconstructed from Computed Tomography (CT) images and Color Cryosection images obtained from the VHM cadaver. Thirteen degrees of freedom were used to describe the orientations of seven bones in the model: clavicle, scapula, humerus, radius, ulna, carpal bones, and hand. All of the major articulations from the shoulder girdle down to the wrist were included in the model. The model was actuated by 42 muscle bundles, which represented the actions of 26 muscle groups in the upper limb. The paths of the muscles were modeled using a new approach called the Obstacle-set Method (33) The calculated paths of the muscles were verified by comparing the muscle moment arms computed in the model with the results of anatomical studies reported in the literature, In-vivo measurements of maximum isometric muscle torques developed at the shoulder, elbow, and wrist were also used to estimate the architectural properties of each musculotendon actuator in the model. The entire musculoskeletal model can be reconstructed using the data given in this paper, along with information presented in a companion paper which defines the kinematic structure of the model (26)  相似文献   

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摘要 目的:研究智能化人机交互和场景模拟对脑卒中患者上肢运动功能的影响,探索其在康复训练中的作用,为脑卒中患者康复提供新的治疗方法和方向。方法:选取2019年1月-2022年12月在我院接收治疗的80例脑卒中患者,按随机数字表法分为对照组和实验,每组40人,对照组接受常规康复治疗,实验组在常规康复治疗基础上增加智能化人机交互和场景模拟训练。比较两组Fugl-Meyer上肢运动功能量表评分(UE-FMA)、患者的生活自理能力Barthel指数、上肢功能测试(UEFT),患侧上肢腕背伸肌的改良Ashworh评分(MAS)以及徒手肌力评估(MMT)。比较两组患者满意度评分。结果:治疗后,两组患者UE-FMA评分与治疗前相比均提高,且实验组显著高于对照组(P<0.05);治疗后,两组患者MBI评分与治疗前相比均提高,且实验组显著高于对照组(P<0.05);治疗后,两组患者UEFT评分与治疗前相比均提高,且实验组显著高于对照组(P<0.05);治疗后,两组患者MMT评分与治疗前相比均提高,且实验组显著高于对照组(P<0.05)治疗后,两组患者MAS评分与治疗前相比均降低,且实验组显著低于对照组(P<0.05);与对照组相比,实验组满意度95%,高于对照组80%(P<0.05)。结论:智能化人机交互和场景模拟训练对脑卒中患者的上肢运动功能有积极的影响,可以有效改善患者的康复效果。  相似文献   

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张云然 《人类学学报》2012,31(3):299-314
本文首先提出了人体相似性的概念和定义, 并进行了数学论证, 导出了标准人体的数学表达方法,然后, 根据90名志愿者的样本具体计算说明了标准人体尺寸的适用性。本文提出的标准人体尺寸处理方法, 可供人种和体型分类、人体模型与服装设计时确定人体各部尺寸, 为利用人体其他节段估测人全身尺寸的可能性提供参考。最后指出, 表示人体尺寸间相互关系的人体常数是存在的; 在设计人体模型时, 不管模型的比例如何, 所设计模型的人体常数需保持与所代表的人群样本的人体常数一致。  相似文献   

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脑瘫、脑卒中、颅脑外伤、多发性硬化等疾病引起上运动神经元病损均可出现肌肉痉挛,给患者的肢体功能造成不良影响。肉毒毒素是肉毒梭状芽孢杆菌产生的一种毒力极强的嗜神经生物毒素,可阻断神经肌肉接头处的乙酰胆碱的释放,导致肌肉松弛性麻痹。一些临床专家利用肉毒毒素(主要为A型肉毒毒素Botulinum toxin type A,BTX-A)的这种生物活性,来治疗肢体肌肉痉挛,已成为相关医学生物学和临床研究的热点之一。  相似文献   

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摘要 目的:探讨脑卒中痉挛性患者经颅磁刺激联合物理治疗后上肢功能改善状况的临床观察。方法:选取我院2018年1月到2020年1月共收治的80例脑卒中患者,所有患者均出现不同部位痉挛现象,将患者随机分为观察组与对照组,每组40例。给予对照组患者常规治疗与康复训练,观察组患者在常规治疗基础上应用低频重复经颅刺激联合肌电生物反馈模式下的康复训练。对比两组患者的治疗效果与上肢功能改善情况。结果:观察组治疗总有效率95.00 %,高于对照组72.50 %(P<0.05);治疗前两组患者的NIHSS评分应用神经功能缺损量表(Neurological deficit scale,NIHSS)、MMSE评分应用认知功能量表(Cognitive function scale,MMSE)、ADL评分应用日常生活能力量表(Activities of daily living scale,ADL)评分对比无显著差异(P>0.05),治疗后,观察组的NIHSS评分低于对照组,ADL评分高于对照组(P<0.05);治疗前两组患者的肱二头肌和肱三头肌均方根值(Root mean square,RMS)对比无显著差异(P>0.05),治疗后,观察组患者的肱二头肌RMS低于对照组,肱三头肌RMS高于对照组(P<0.05);治疗前两组患者的运动功能评估表中的上肢功能部分(Upper limb function in motor function assessment table,FMA-UE)、手部精细化动作及上肢功能测量表(Measurement table of hand fine movement and upper limb function,Carroll)评分对比无显著差异(P>0.05),治疗后,观察组患者的FMA-UE、Carroll评分高于对照组(P<0.05)。结论:对脑卒中上肢痉挛患者在常规治疗与康复训练的基础上应用低频重复经颅刺激联合肌电生物反馈模式下的康复训练,虽然对患者的认知功能无明显影响,但是能提升患者上肢痉挛的治疗效果,促进患者上肢功能恢复,提高生活能力,值得临床应用推广。  相似文献   

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目的:研究显示上肢动脉铸型标本方法,为临床应用及教科研提供直观细致的局部循环标本。方法:截取新鲜成人尸上肢6例,从腋动脉、尺动脉及桡动脉分别向肢体两端进行多点灌注牙托粉、过氯乙烯等填充剂,然后进行腐蚀冲洗处理。结果:上肢动脉铸型标本外形美观,具有结构完整性和连续性,血管分支毗邻关系明确,疏密有度。结论:采用沿动脉管道多点插管灌注法是制作上肢动脉铸型标本较为有效的方法。  相似文献   

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The primary purpose of this study was to compare static and dynamic optimization muscle force and work predictions during the push phase of wheelchair propulsion. A secondary purpose was to compare the differences in predicted shoulder and elbow kinetics and kinematics and handrim forces. The forward dynamics simulation minimized differences between simulated and experimental data (obtained from 10 manual wheelchair users) and muscle co-contraction. For direct comparison between models, the shoulder and elbow muscle moment arms and net joint moments from the dynamic optimization were used as inputs into the static optimization routine. RMS errors between model predictions were calculated to quantify model agreement. There was a wide range of individual muscle force agreement that spanned from poor (26.4% Fmax error in the middle deltoid) to good (6.4% Fmax error in the anterior deltoid) in the prime movers of the shoulder. The predicted muscle forces from the static optimization were sufficient to create the appropriate motion and joint moments at the shoulder for the push phase of wheelchair propulsion, but showed deviations in the elbow moment, pronation–supination motion and hand rim forces. These results suggest the static approach does not produce results similar enough to be a replacement for forward dynamics simulations, and care should be taken in choosing the appropriate method for a specific task and set of constraints. Dynamic optimization modeling approaches may be required for motions that are greatly influenced by muscle activation dynamics or that require significant co-contraction.  相似文献   

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The purpose of this study was to examine whether cardiorespiratory responses to combined rhythmic exercise (60 contractions · min–1) was affected by different combinations of upper and lower limb exercise in seven healthy women. Six different rhythmic exercises were compared: 6-min rhythmic handgrip at 10% of isometric maximal voluntary contraction (MVC) (H10); 6-min rhythmic plantar flexion at 10% MVC (P10); exhausting rhythmic handgrip at 50% MVC (H50); exhausting rhythmic plantar flexion at 50% MVC (P50); H50 was added to P10 (P1OH50); and P50 was added to H10 (H10P50). Exercise duration, after handgrip was combined with plantar flexion (P10H50), was shorter than that of H50, although the exercise duration of HIOP50 was not significantly different from P50. No significant difference was found between the difference from rest in oxygen uptake ( O2) during H10P50 and the sum of O2 during H10 and P50. Also, the differences from rest in forearm blood flow ( FBF) and calf blood flow ( CBF) during H10P50 were not significantly different from FBF in H10 and from CBF in P50. In contrast, O2 in P10H50 was lower than the sum of O2 in P10 and H50 (P < 0.05), and J FBF in P10H50 was lower than that in H50 (P < 0.05) , while CBF was not significantly different between P1OH50 and P10. The changes in heart rate from rest (d HR) during the combined exercises were lower than the sums of HR in the corresponding single exercises (P < 0.05). These results demonstrated an inhibitory summation of several cardiorespiratory responses to combined exercise resulting in a reduction in exercise performance which would seem to occur easily when upperlimb exercise is added to lower limb exercise.  相似文献   

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We dissected the left upper limb of a female orangutan and systematically recorded muscle mass, fascicle length, and physiological cross-sectional area (PCSA), in order to quantitatively clarify the unique muscle architecture of the upper limb of the orangutan. Comparisons of the musculature of the dissected orangutan with corresponding published chimpanzee data demonstrated that in the orangutan, the elbow flexors, notably M. brachioradialis, tend to exhibit greater PCSAs. Moreover, the digital II-V flexors in the forearm, such as M. flexor digitorum superficialis and M. flexor digitorum profundus, tend to have smaller PCSA as a result of their relatively longer fascicles. Thus, in the orangutan, the elbow flexors demonstrate a higher potential for force production, whereas the forearm muscles allow a greater range of wrist joint mobility. The differences in the force-generating capacity in the upper limb muscles of the two species might reflect functional specialization of muscle architecture in the upper limb of the orangutan for living in arboreal environments.  相似文献   

13.
BackgroundHandwriting is a fundamental skill needed for the development of daily-life activities during lifetime and can be performed using different forms to hold the writing object. In this study, we monitored the sEMG activity of trapezius, biceps brachii, extensor carpi radialis brevis and flexor digitorum superficialis during a handwriting task with two groups of subjects using different grasp patterns.Subjects and methodsTwenty-four university students (thirteen males and eleven females; mean age of 22.04 ± 2.8 years) were included in this study. We randomly invited 12 subjects that used the Dynamic Tripod grasp and 12 subjects that used the Static Tripod grasp.ResultsThe static tripod group showed statistically significant changes in the sEMG activity of trapezium and biceps brachii muscles during handwriting when compared to dynamic tripod group’s subjects. No significant differences were found in extensor carpi radialis brevis and flexor digitorum superficialis activities among the two groups.ConclusionThe findings in this study suggest an increased activity of proximal muscles among subjects using a transitional grasp, indicating potential higher energy expenditure and muscular harm with the maintenance of this motor pattern in handwriting tasks, especially during the progression in academic life.  相似文献   

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目的:探讨体外反搏对颅脑外伤术后患儿早期上肢功能恢复的影响。方法:选择2016年1月~2018年1月在上海市儿童医院康复科就诊的36例颅脑外伤术后患儿,将其随机分成观察组和对照组,每组18例患者。对照组患儿给予常规作业治疗,治疗组患儿在对照组的基础上增加体外反搏治疗。治疗3个月后,比较两组患儿治疗前后精细运动能力(FMFM)和改良Barthel指数评分。结果:经3个月治疗后,两组患儿精细功能和日常生活活动能力均较治疗前有所提高,观察组和对照组FMFM评分和Barthel指数明显高于治疗前,且观察组明显FMFM评分和Barthel指数优于对照组(142.43±18.65 vs. 136.48±15.67;81.19±10.60 vs.74.52±12.93),差异均有统计学意义(P0.05)。结论:联合体外反搏能更好地改善颅脑外术后早期的上肢功能。  相似文献   

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The paper proposes the concept and definition of “human body similarity” and demonstrates this concept with a mathematical method derived from the standard human- body’s expression. This standard human body size is examined by processing body size data of 90 volunteers. This method can provide estimates for whole body size by using segment size? measurements? when? classifying? the? human? race? and? its? body? configuration.? There? exists? a? constant in the expression of human body size correlation, as well as in designing the human body model.  相似文献   

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Recent works have demonstrated a linear relationship between muscle activation and shear modulus in various superficial muscles. As such, it may be possible to overcome limitations of traditional electromyography (EMG) methods by assessing activation using shear wave elastography. However, the relationship has not been wholly validated in deep muscles. This study measured the association between squared shear wave velocity, which is related to shear modulus, and activation within superficial and deep muscles. This relationship was also compared between surface and intramuscular EMG electrodes. We simultaneously recorded EMG and shear wave velocity in one deep (brachialis) and one superficial (brachioradialis) muscle in ten healthy individuals during isometric elbow flexion across a wide range of contraction intensities. Muscle activation and squared shear wave velocity demonstrated good reliability (ICC > 0.75) and showed a linear relationship (P < 0.05) for all muscle/EMG electrode type combinations (study conditions) after down-sampling. Study condition was not a significant within-subject factor to the slope or intercept of the relationship (P > 0.05). This work demonstrates that activation of both superficial and deep muscles can be assessed noninvasively using ultrasound shear wave elastography and is a critical step toward demonstrating elastography’s utility as an alternative to EMG.  相似文献   

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This study aimed to evaluate test and retest reliability according to examiner experience with the three-dimensional kinematics of the trunk, scapula, and arm segments during flexion and unilateral abduction of the arm. Ten men and 10 women (mean age, 25.1 [1.1] years) participated in this study. Each volunteer participated in six test sessions, four on the first day (two for each examiner) and two on the second day (one for each examiner). A 48-h interval was given between test days. The assessments were made by one examiner with movement analysis experience and a second examiner without experience. For each session (intra-day), the volunteers performed five repetitions of unilateral arm flexions and abductions using their dominant arms. After 1 h, the data were re-collected and all markers were replaced. Data from the trunk, scapula, and arm were analysed at 30°, 60°, 90°, and 120° of arm flexion and abduction using intraclass coefficient correlation, standard error of the measurement, and analysis of variance. The results did not differ between the experienced and inexperienced examiners except for trunk axial rotation at all studied angles and for arm rotation at 120° of abduction. The examiner previously trained in movement analysis marker placement demonstrated the same intra-tester reliability as the inexperienced tester when marker placement accuracy was the variable of interest.  相似文献   

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Deep preauricular sulci were identified on abdominal radiographs in 29 of 190 (15%) adult females and in none of 110 adult males. To assess the value of the deep preauricular sulcus as an index of past pregnancy, we examined gravidity and parity records of 190 women, using standard films that included the sacroiliac region. Deep, radiographic preauricular grooves were identified in 4 of 41 (10%) nulliparous women and in 25 of 149 (17%) women with positive pregnancy histories. We also examined radiographs obtained before and after pregnancy in six primigravidas. No evidence of radiographic changes in the preauricular grooves was seen in any of the six women. We conclude that the presence of a deep, radiographic preauricular sulcus is not necessarily an indication of past pregnancy.  相似文献   

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