基于表面肌电信号的手势识别与分析

目的 研究利用前臂及手部表面肌电( surface electromyography,sEMG)信号进行手势识别的方法,以及不同 手势下拇指、食指的关节角度,探讨 sEMG 信号控制外骨骼手的可行性。 方法 采集 20 名健康右利手受试者右侧 前臂及手部 6 块肌肉 sEMG 信号。 提取 sEMG 信号的时域特征值,对比人工神经网络( artificial neural network, ANN)、K-近邻(K-nearest neighbor, KNN)、决策树(decision tree, DT)、随机森林( random forest, RF)和支持向量机(support vector machine, SVM)等多种分类器对 6 种日常手势进行识别。 同时,采用 Vicon 摄像机跟踪系统捕捉右手拇指、食指运动轨迹,计算拇指、食指关节角度。 结果 利用前臂及手部 sEMG 信号可以实现 6 种手势的模式识别,其中 ANN 分类器的分类预测效果最好,测试集预测精度可达 97. 9% ,Kappa 系数可达 0. 975。 同时,计算得到不同手势下拇指、食指的关节角度,并进行不同手势下关节角度相关性分析。 结论 利用前臂及手部 sEMG 信号进 行手势识别,能够实现具有几乎完全一致的分类预测结果。 研究结果证明了 sEMG 信号手势识别应用于外骨骼手 控制的可行性。     

补肾填精法治疗多系统萎缩致体位性低血压疗效及对患者自主神经功能的影响

目的:探讨补肾填精法治疗多系统萎缩(MSA)致体位性低血压(OH)的疗效及对患者自主神经功能的影响。方法: 选取MSA患者80例,随机分为观察组和对照组各40例。对照组给予单纯西药对症治疗,观察组在对照组用药基础上给予补肾填精法治疗。比较两组治疗前后卧立位收缩压差、卧立位舒张压差、肛门括约肌肌电图(EAS-EMG)情况、交感皮肤反应(SSR)情况及临床疗效。结果:治疗后,两组卧立位收缩压差、卧立位舒张压差值均明显减少,观察组更明显(均P<0.05)。治疗后,两组自发电位出现率、募集电位单纯相出现率及MUP平均时限均明显降低,且观察组更明显(均P<0.05)。观察组治疗总有效率高于对照组(P<0.05)。治疗后,两组SSR潜伏期缩短,波幅增高,且观察组更明显(均P<0.05)。结论:补肾填精法可改善多系统萎缩致体位性低血压患者的直立性低血压症状,促进患者自主神经功能康复,改善临床症状,临床疗效较为满意,且安全性高。     

Effects of Kinesio taping in rectus femoris activity and sit-to-stand movement in children with unilateral cerebral palsy: placebo-controlled,repeated-measure design

Background: Although it has been commonly used in rehabilitation sets, there is a lack of studies verifying the effects of Kinesio taping to improve functionality in children with Cerebral Palsy (CP). This information would promote evidence-based practice.

Purpose: To verify the effects of Kinesio taping in the performance of sit-to-stand movement in children with unilateral CP.

Methods and materials: A blinded, single placebo-controlled and repeated-measure design. The setting was the rehabilitation clinic of the university and care facilities. A total of 11 children from 6 to 12 years of age (mean: 10.5 years; standard deviation: 2.8 years) and classified as levels I and II by the Gross Motor Function Classification System were included. Kinesio taping was applied over the rectus femoris of the affected limb. Three taping conditions were used: Kinesio taping, without Kinesio taping and placebo. Three seat heights were used: neutral (100%), lowered (80%), and elevated (120%). Muscle activity (electromyography) and trunk and lower limb alignment (kinematics) were evaluated as body structures and function measures. The time required to perform sit-to-stand was used as a functionality measure. Mixed analysis of variation (ANOVA) measured angular variables of the hip, knee, ankle, and rectus femoris activity. Repeated ANOVA measured angular variables of trunk and pelvis and total duration. Significance was accepted for values of p?≤?0.05.

Results: Kinesio taping increased rectus femoris activity, decreased peak flexion of the trunk, knee, hip, and ankle, and increased trunk extension in the end of sit-to-stand when compared with without Kinesio taping and placebo. Total duration was decreased with lower effect sizes.

Conclusions: Immediate application of Kinesio taping modified body structures and function measures during sit-to-stand in children with unilateral CP, but it did not alter functionality.

• Implications for Rehabilitation

• Evidence-based practice about the use of Kinesio taping in Cerebral Palsy.

• Knowledge about alternative rehabilitation techniques in Cerebral Palsy.

• Knowledge about sensory stimulation in Cerebral Palsy.

• Effectiveness of Kinesio taping in muscle activation.

     

Gait Parameters and Muscle Activation Patterns at 3, 6 and 12 Months After Total Hip Arthroplasty

Gait analysis was performed on 20 patients with unilateral hip prosthesis (3, 6 and 12 months post-operatively) and 20 controls to investigate their gait characteristics and muscle activation patterns. One year after the intervention, patients still walked with a higher percentage of “atypical” cycles, a prolonged heel contact, a shortened flat foot contact, a reduced hip dynamic range of motion and abnormal timing in the muscle activation patterns of tibialis anterior, gastrocnemius lateralis, biceps femoris and gluteus medius, with respect to the control group. Although the gait velocity and the knee range of motion improved from 3 to 6 months post-surgery, the above mentioned parameters did not improve from 6 to 12 months. THA patients failed to obtain normal gait one year after surgery.     

Shifts in EMG spectral power during fatiguing dynamic contractions

Introduction: We examined the etiology of the electromyographic (EMG) spectral shift during dynamic fatigue. Methods: Nineteen subjects (mean ± SD age = 22.4 ± 1.6 years) performed 50 consecutive maximal concentric isokinetic contractions of dominant leg extensors. Surface EMG signals were detected from the vastus lateralis, rectus femoris, and vastus medialis during each contraction, processed with a wavelet analysis, and the resulting spectra were decomposed with a nonparametric spectral decomposition procedure. Results: The results indicated that the decreases in EMG frequency during the 50 contractions were generally due to reductions in high‐frequency power and increases in low‐frequency power. In addition, the spectral shifts were most pronounced for the rectus femoris, followed by the vastus lateralis, and then the vastus medialis. Conclusions: The spectral decomposition procedure is much more sensitive for tracking dynamic fatigue than is EMG mean frequency or median frequency. Muscle Nerve 50 : 95–102, 2014     

大鼠骨髓间充质干细胞移植治疗喉返神经损伤实验研究

目的通过建立喉返神经损伤(recurrent laryngeal nerve injury)动物模型,探讨自体骨髓间充质干细胞(BMSC)移植对喉返神经损伤的治疗效果。方法随机数字表法将40只SD大鼠分成两组,每组20只。对全部大鼠手术复制喉返神经损伤动物模型。一组大鼠骨髓,培养、分化骨髓间充质干细胞后,自体进行干细胞移植为实验组。另一组为生理盐水注射对照组。建立模型3 d后,将BMSC诱导后的类神经细胞0.2 ml注射移植至大鼠左侧喉返神经损伤处,于移植后7、14、21、28、60 d,观察喉返神经电生理指标。结果实验组和对照组喉返神经损伤后均有不同程度的失神经和神经再生现象。移植14 d后实验组与对照组喉返神经电生理检测的潜伏期和波幅平均值分别为(1.78±0.41)ms与(2.36±0.16)ms(t=5.72、P<0.01)和(0.69±0.09)mV与(0.46±0.07)mV(t=8.18、P<0.01),差异有统计学意义。60 d后实验组与对照组喉返神经电生理检测的潜伏期和波幅分别为(0.93±0.03)ms与(1.16±0.18)ms(t=5.50,P<0.01)和(1.33±0.18)mV与(1.04±0.20)mV(t=4.64、P<0.01),差异有统计学意义。结论自体骨髓间充质干细胞移植对喉返神经损伤有促修复作用,治疗效果明显。     

赤凤迎源针法治疗脑卒中后肩手综合征的疗效观察

目的：探讨表面肌电图（sEMG）在学龄期脑瘫患儿疗效评估中的应用价值。方法：对60例痉挛型双瘫型脑瘫患儿进行综合康复治疗。治疗前后分别采用粗大运动功能测试量表（GMFM）和表面肌电仪对患儿进行测试,分析肌电积分值（iEMG）、均方根值（RMS）、平均功率频率（MPF）、中位频率（MF）、平均肌电值（AEMG）。结果：60例患儿治疗前后GMFM量表A、B、C区评分比较差异无统计学意义,治疗3个月后D、E区及总分均较治疗前明显提高（P〈0．01）。60例患儿治疗3个月后功能位腓肠肌、股四头肌iEMG值均较治疗前明显下降（P〈0．01）,RMS、AEMG、MF及MPF值治疗前后差异无统计学意义;最大等长收缩（MIVC）状态下腓肠肌、股四头肌iEMG、RMS及AEMG值均较治疗前明显提高（P〈0．01）,MF及MPF值治疗前后差异无统计学意义。结论：sEMG能够定量反映肌肉功能的水平,可作为脑瘫患儿疗效评估的电生理学方法。     

肌电生物反馈对脑卒中偏瘫患者坐-站转移的影响

目的：探讨肌电生物反馈治疗联合常规康复治疗对偏瘫患者坐一站转移训练的疗效及临床意义。方法：偏瘫患者60例,随机分为观察组和对照组各30例,2组均采用常规康复治疗,观察组加用肌电生物反馈参与的坐一站转移训练。治疗前后比较2组患者患侧大腿的肌电值百分比及5m起立一行走时间。结果：治疗8周后,2组患者患侧下肢肌电值百分比较治疗前明显提高,且观察组更高于对照组（均P〈0．01）;2组患者的5m起立一行走时间较治疗前明显缩短,观察组更短于对照组（均P〈0．01）。结论：联合肌电生物反馈治疗对脑卒中偏瘫患者的改善效果优于单纯传统康复治疗。     

青少年特发性脊柱侧凸腰腹部肌群表面肌电信号特征研究

目的 研究青少年特发性脊柱侧凸(AIS)患者不同站立位腰腹部肌群表面肌电信号特征.方法 选取33例AIS患者作为AIS组,15例健康青少年作为健康对照组,采用FlexComp Infiniti十通道表面肌电分析系统测试腰腹部肌群的表面肌电信号.所有研究对象分别站立在稳定平面和软垫上、去除和不去除视觉听觉干扰时进行测试.比较2组研究对象腰腹部肌群激活率.结果 站立在稳定平面和软垫上、去除和不去除视觉听觉干扰时,AIS组凹侧顶椎水平椎旁肌激活率分别为4.91％ MVIC、5.22％ MVIC、5.51％MVIC、6.01％ MVIC,AIS组凸侧顶椎水平椎旁肌激活分别为6.45％ MVIC、7.69％ MVIC、8.31％ MVIC、8.77％ MVIC,AIS组凹侧顶椎水平椎旁肌激活均小于凸侧(P＜0.01).AIS组凸侧顶椎水平椎旁肌在稳定静止站立位的激活率小于去除视觉和听觉干扰、不稳定的站立位(P＜0.05).结论 AIS患者双侧顶椎水平椎旁肌激活率不对称;在去除视觉和听觉干扰的不稳定站立位下,AIS患者凸侧顶椎水平椎旁肌更易激活.