压力生物反馈仪测试腰痛的信度评价

背景：关于下背痛的治疗方案种类繁多,至今仍没有一个确定的治疗手段。压力生物反馈仪是测量腹部肌肉活性的工具,对腰痛患者测试的信度研究较少。目的：探讨压力生物反馈仪用于评估腰痛患者的信度及可行性。方法：将符合入选条件的30例慢性腰痛患者作为受试者,选取4组动作,分别为动作A俯卧位,动作B仰卧屈膝位,动作C仰卧单侧屈髋屈膝位,动作D俯卧单侧肩关节前屈位,分别测试不同动作下的腹内压,由同一测试者在1周内对受试者进行前后两次测试。信度评价指标为组内相关系数(ICC)。结果与结论：动作A具有良好的信度,ICC值为0.853 (95%CI：0.691-0.930);动作B具有中等相关性,ICC值为0.751(95%CI：0.477-0.882);动作C具有中等相关性,ICC值为0.789(95%CI：0.557-0.900);动作D具有良好的相关性,ICC值为0.892(95%CI：0.641-0.919)。因此压力生物反馈用于评估腰痛具有良好的信度,可用于腰痛患者的评价。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

不同体位下青少年特发性脊柱侧凸患者椎旁肌的超声影像测量与分析

目的　超声评估青少年特发性脊柱侧凸（AIS）患者脊柱两侧椎旁肌的对称性和形态学特征,为AIS运动治疗提供线索和依据。 方法　收集23例AIS患者（患者组）与23例无脊柱侧凸的青少年（对照组）,应用超声对两组受试者在休息位（腰背部肌肉取俯卧位、腹部肌肉取仰卧位）、站立位下测量椎旁肌（T12~L5水平竖脊肌、T12~S1水平多裂肌、腰方肌和腹横肌）厚度,计算肌肉厚度变化率。 结果　休息和站立位时,AIS患者主弯曲线T12~L4水平竖脊肌、T12~S1水平多裂肌、腰方肌和腹横肌（仅休息位）凸侧厚度均小于凹侧（P<0.05）;休息和站立位时,AIS患者凸侧竖脊肌、多裂肌、腰方肌和腹横肌（仅休息位）厚度均小于对照组（P<0.05）;AIS患者凹凸两侧的竖脊肌收缩厚度变化率均小于对照组（P<0.05）。 结论　休息和站立位时,AIS患者主弯曲线多个椎体节段椎旁肌对称性不良,较对照组凸侧椎旁肌厚度薄。     

基于AnyBody仿真和肌电测试分析不同体质量指数男性青年球类运动中的生物力学特征

文题释义： Anybody仿真：使用数学建模技术模拟人体肌肉骨骼在不同载荷中的情况,计算各块肌肉和关节的受力、变形、肌腱的弹性能、拮抗肌肉运动和其他对于工作中的人体有用的特性,以计量方式计算出人体对于环境的反应,兼与人机工程学和生物力学分析,为人体运动建模、人机工程学产品性能改进和生物医学工程研究提供平台。 均方根振幅：是将振幅平方的平均值开平方,把振幅值平均然后开方,最原始的是针对正弦波推导出来的,但实际上对所有的波形都适用,均方根值(RMS)也称作为效值,表示在一段周期内,参加肌肉活动的肌肉瞬间肌电图振幅均方根值,是一定时间内肌电位值平方和的平方根。 背景：Anybody肌肉骨骼建模系统,使用数学建模技术模拟人体骨骼、肌肉和环境的关系,可对人体的逆向动力学进行研究,得出下肢三关节最大肌肉力等指标。 目的：研究24名不同体质量指数男大学生在坐瑞士球一个动作周期的下肢肌肉力值,及受试者在坐瑞士球与平凳的均方根肌电平均值对比情况。 方法：将24名男大学生按体质量指数分为正常组、超重组、肥胖组,用BTS三维红外动作捕捉系统、Kistler 三维测力台、BTS表面肌电测试系统,同步记录动力学和肌电参数,以单因素方差分析定性比较不同组间肌力和肌电参数差异,用定量差异分析法对比均值差异。 结果与结论：①肌肉力量方面,由坐到站过程中,正常组与肥胖组相比,股直肌、半膜肌、股二头肌长头、腘肌、比目鱼肌、胫骨前肌差异显著(P < 0.05,0.47≤QD<0.80),股方肌与耻骨肌的两组肌肉力差异极其显著(P < 0.01,QD≥0.80);超重组与肥胖组肌肉力相比,股方肌具有显著性差异(P < 0.05,0.47≤QD<0.80),由站到坐过程中,正常组与肥胖组相比,缝匠肌、拇长伸肌、腓肠肌肌肉力差异显著(P < 0.05,0.47≤QD<0.80);②均方根肌电值方面,坐平凳状态下,由坐到站过程中,正常组与肥胖组相比,股二头肌和腓肠肌差异显著(P < 0.05,0.47≤QD<0.80),由站到坐过程中,正常组与肥胖组相比,股直肌差异显著(P < 0.05,0.47≤QD<0.80);坐瑞士球状态下,由坐到站过程中,正常组与肥胖组相比,胫骨前肌、股二头肌差异显著(P < 0.05,0.47≤QD<0.80);由站到坐过程中,正常组与肥胖组相比,腓肠肌、右竖脊肌肌电值差异显著(P < 0.05,0.47≤QD<0.80)。提示：①各组由坐到站过程中主导发力肌肉是臀中肌、股外侧肌、股二头肌长头、股直肌、腓肠肌、胫骨前肌、比目鱼肌,由站到坐过程中下肢臀中肌、股外侧肌和股二头肌长头、腓肠肌、胫骨前肌、比目鱼肌主导发力;②与坐平凳相比,受试者在坐瑞士球时胫骨前肌、股直肌、股二头肌、腓肠肌均方根肌电值高。ORCID: 0000-0003-0520-5606(庞博) 中国组织工程研究杂志出版内容重点：人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程     

利用生物电阻抗法研究进藏工作的汉族人群骨骼肌含量

目的 探讨进藏工作汉族成年人群和辽宁汉族成年人群骨骼肌含量分布的特点及差异。 方法 随机抽取进藏工作的辽宁本地汉族、辽宁汉族健康成人作为研究对象,共选取进藏辽宁本地汉族成人223名（男95,女128）;辽宁汉族成人302名（男126,女176）,应用体成分分析仪对受试者的体重、全身肌肉量、躯干肌肉量、左上肢肌肉量、右上肢肌肉量、左下肢肌肉量、右下肢肌肉量进行测量。并将所有结果输入SPSS 22.0统计学软件分析,应用独立样本 t 检验等相关统计学方法处理。 结果 进藏汉族成年人群的体重、躯干肌肉量、左上肢肌肉量、右上肢肌肉量、左下肢肌肉量及右下肌肉量均小于辽宁本地汉族人群,差异有显著性（P<0.01或P<0.05）;进藏汉族和辽宁汉族人群的男性肌肉量大于女性人群,差异有显著性（P<0.01或P<0.05)。 结论 辽宁汉族人群进入西藏高原地区后,身体各部分肌肉量数值均明显下降。人体成分的改变可受性别、高原缺氧环境等多种因素影响。     

基于超声弹性成像的女性盆底肌肉定量评估方法

女性盆底功能障碍性疾病是中老年女性的常见疾病,现已成为威胁女性健康的5种常见慢性疾病之一。盆底支撑结构中,盆底肌肉群的支撑作用至关重要,因此盆底肌肉评估对于女性盆底功能障碍性疾病的诊疗具有重要的临床价值。提出一种无创客观的肌肉运动分析方法,基于经会阴超声检测手段,同步获取50例具有不同脱垂程度女性主动收缩肌肉时的超声视频数据及阴道内压数据,应用二维弹性成像算法追踪盆底肌位移场,提取特征点的位移曲线,对比分析能有效完成指定动作的37例不同脱垂程度患者的位移结果,发现提取接近耻骨处特征点的切向位移参数(M_Pu)与临床脱垂测量参数(L_BP)具有相关性(r=-0.93),同时通过在指定的肌肉慢缩运动中的肌力维持时间均值和最大厚度均值对盆底肌的持续控制能力进行评估,结果与被试临床脱垂分级表现具有显著相关性。结果表明,这种方法可实现对盆底肌肉自身生物力学特性的客观定量评估,为临床脱垂诊断提供重要的参考价值。     

人体下颈椎显微骨硬度体外测量的实验研究

目的 探讨人体下颈椎C₃~C₇椎骨显微骨硬度的分布特征及其临床意义。方法 3具新鲜成人尸体标本,分别为62岁男性(标本A)、45岁女性(标本B)、58岁男性(标本C),由河北医科大学解剖学教研室提供。取其下颈椎C₃~C₇段脊柱,剔除附着软组织。每个椎骨分为椎体区和附件区两部分,使用高精慢速锯分别经椎体中部垂直于椎体上下终板、右侧椎弓根长轴、左侧上下关节突长轴切割3 mm厚骨切片各1片, 并用砂纸打磨,15块椎骨共制成45片骨切片。应用维氏显微硬度测量仪测量骨组织切片不同区域皮质骨和松质骨的显微硬度值,每一个区域选取5个有效显微骨硬度值,全体有效值的平均值作为该区域的硬度值。结果 15块椎骨共计获得825个有效显微骨硬度测量值。 C₃~C₇总体骨硬度值为11.10～47.80 HV,其中皮质骨为(26.04±4.84) HV、松质骨为(22.92±4.78) HV。椎体区皮质骨硬度值为(25.46±4.86) HV、松质骨硬度值为(21.10±4.97) HV,附件区皮质骨硬度值为(26.50±4.78) HV、松质骨硬度值为(24.75±3.80) HV,附件区高于椎体区,差异均有统计学意义(t=2.800、4.978, P值均＜0.05)。3具尸体标本各自的下颈椎在不同部位的骨显微硬度值不同,但椎体区的皮质骨与松质骨骨硬度值均低于附件标本的皮质骨与松质骨骨硬度,其中松质骨之间的差异均有统计学意义(t_A=4.316、t_B=2.364、t_C=2.107, P值均＜0.05);而皮质骨中,仅标本B的差异有统计学意义(t=2.498,P＜0.05)。C₃~C₇各椎骨不同部位的硬度值分布规律与总体一致:椎体区的骨硬度值均低于附件区;其中C₃、C₅、C₆、C₇松质骨的骨硬度值差异具有统计学意义(P值均＜0.05)。 附件分区中,上关节突皮质骨骨硬度低于椎弓根、椎板、横突、下关节突皮质骨骨硬度,差异具有统计学意义(F=8.590, P＜0.05);椎体分区中,下终板皮质骨骨硬度高于上终板和外周终板皮质骨骨硬度,差异具有统计学意义(F=16.365, P＜0.05)。结论 下颈椎椎骨不同部位、不同区域的骨显微硬度存在差异,附件区的皮质骨/松质骨骨硬度分别高于椎体区的皮质骨/松质骨骨硬度。该分布规律是人体活动过程中适应应力应变的生理改变,可以为三维有限元分析、3D打印及术前模拟提供数据支持。     

踝足矫形器人机耦合仿真刚度对步态生物力学影响的评价方法

目的 为更好评价踝足矫形器(ankle-foot orthosis, AFO)的人机工效,提出一种 AFO 人机耦合仿真刚度对步态生物力学影响的评价方法。 方法 首先,评测两种 AFO 的力学特性并量化其刚度;其次,采集 30 名受试者在正常与穿戴两种不同刚度 AFO 行走条件下的运动学及动力学数据;最后,通过仿真计算,定量对比分析 AFO 刚度对 行走中下肢关节角度、关节力矩与肌肉力的影响。 结果 在穿戴两种刚度 AFO 情况下,支撑相踝关节背屈峰值角度、膝关节屈曲峰值角度和髋关节伸展峰值角度均显著增加(P<0. 05),比目鱼肌与腓肠肌峰值肌肉力呈现增加趋势。 踝关节跖屈峰值角度、髋关节屈曲峰值角度与髋关节屈曲峰值力矩均显著降低(P<0. 05)。 结论 本文所提出的 AFO 人机耦合仿真方法可以有效实现不同刚度对步态生物力学影响的定量评估,该方法同样也适用于评估和优化其他辅助器具的人机工效,可以为 AFO 的选配、适配、优化设计提供方法指导。     

腰椎退行性侧凸患者椎旁肌的形态学改变

目的　观察腰椎退行性侧凸患者两侧椎旁肌的形态学改变,分析其临床意义。 方法　回顾性分析我院2015年1月-2017年12月住院的84例腰椎退变性侧凸患者。按患者顶椎位置分为3组。A组：顶椎位于L2-3椎间盘,B组：顶椎位于L3椎体,C组：顶椎位于L3-4椎间盘。使用image pro PLus软件测量椎旁肌肉相关数据。 结果　（1）A组顶椎节段多裂肌（MF）面积比凸侧大于凹侧,MF脂肪浸润程度凸侧小于凹侧;（2）腰大肌（PS）面积比凸侧小于凹侧, PS脂肪浸润程度凸侧小于凹侧。（3）A、B、C 3组在顶椎上一个及下一个椎间盘平面与顶椎椎间盘平面有相似的结果。 结论　退行性侧凸患者凸凹侧椎旁肌退变程度不同,凹侧大于凸侧,退变节段主要发生于顶椎上、下各一节段。且肌肉退变主要以肌肉的脂肪浸润程度增加为主。     

广西汉族和壮族大学生肺活量与肌肉参数的相关性分析

目的 探讨广西某高校汉族、壮族大学生肺活量与肌肉参数的相关性。方法 随机抽取1909名广西某高校在读大学生,采用MC-180体成分仪测量其肌肉参数,肺活量测试仪测量其肺活量。按《国家学生体质健康标准》进行身高、体重测试。将受试者肺活量分数分为4组：<60分、60～79分、80～89分、≥90分。采用SPSS 23.0统计学软件进行分析。结果 不同肺活量分数段汉族男、女大学生身高、年龄、体重、身体质量指数（BMI）、肌肉参数存在组间差异（均P<0.05）,壮族女大学生身高、体重、BMI、肌肉参数（除左上肢肌肉量）存在组间差异（均P<0.05）;汉族男大学生身高、肌肉参数最大值主要集中在≥90分组,呈上升趋势,汉族、壮族女大学生身高、体重、BMI、肌肉参数在<60分、60～79分、80～89分组上升趋势,在≥90分组各指标略有下降,壮族女大学生左上肢肌肉量组间差异不明显。汉族男、女大学生年龄、身高、体重、BMI、肌肉参数与肺活量成显著正相关（均 r>0,均 P<0.01）;壮族男、女大学生身高、体重、肌肉参数与肺活量成显著正相关（均 r>0,均 P<0.01）,左上肢肌肉量与肺活量相关性不显著（P>0.05）。结论 年龄、身高、体重、BMI、肌肉参数的增加对两民族大学生肺活量的增加有一定正性作用,左上肢肌肉量的变化对壮族大学生肺活量的影响不明显,汉族大学生各肌肉参数与肺活量的相关性强于同性别壮族大学生。     

利用生物电阻抗法分析西藏藏族青少年肌肉发育特点

目的 利用生物电阻抗分析法,通过测量得出西藏藏族青少年身体各部肌肉质量的数值,提出适合于西藏藏族青少年的肌肉质量基准值,进而探讨西藏藏族青少年的肌肉发育特点与规律。方法 在知情同意的情况下,整体随机抽取西藏藏族的健康青少年作为研究对象,其父母均为藏族,共选取1427人(男性710、女性717),应用体成分分析仪对所有受试者进行检测,得出全身肌肉量、躯干肌肉量、左上肢、右上肢、左下肢、右下肢肌肉量。所有结果输入SPSS19.0统计软件包,进行独立样本t 检验和方差分析统计学处理。 结果 西藏藏族青少年各年龄段的全身肌肉量、躯干肌肉量、左上肢、右上肢、左下肢、右下肢肌肉量,在12岁之前有性别差异,
但不明显;12岁之后,以上各项数据均出现性别间差异的显著性,均表现为男性大于女性（P <0.05或P <0.01）,而且随着年龄增长,这种差异越趋明显。12岁之后,女性的增长幅度出现显著下降,而男性在15岁之后,增长趋势才开始下降,而女性此时几乎进入肌肉生长发育的平台期。结论 西藏藏族青少年的肌肉含量随年龄变化特点与体内激素分泌水平有关,体现了不同发育时期的生理特点。     

Stiffness in healing fractures

Methods are available for direct measurement of stiffness in fracture healing. The methods are generally dissimilar in their technique and in some cases the applied assumptions are contrary to the principles of basic mechanics. External fixation provides the potential for direct measurement of fragment end movement, and techniques associated with this type of treatment have been applied in Belgium on more than 500 patients. These results are generally presented as decreases in flexure of the fixator bar due to constant loading, representative of increases in fracture stiffness. The same procedure is adopted to internal fixation plates and also direct strain gauge application to the healing bone--there are obvious complications due to electrical connections in the latter case. The biomedical changes occurring during healing are illustrated by the work at Cardiff where a biphase characteristic has been identified. The method used has the disadvantage in requiring the removal of the fixator for the application of the stiffness sensor recording deflection and rotation. The advantages of the technique include the more precise modeling of the bending characteristic of the tibia (the results refer to this particular skeletal element). The experimental studies at Oxford show evidence of enhanced osteogenesis when controlled intermittent deformation is applied in a cyclic manner. In a group of some 50 patients treated with induced micromovement, there is evidence that the rate of increasing fracture stiffness would allow removal of the fixator at 15 weeks compared with 24 weeks in the group with rigid fixation. The exact technique of measuring fracture stiffness has to be compared with other noninvasive test methods which include radiological examination, ultrasound, resonant vibration, and modal analysis. Many of these methods are based on linear elastic relationships which are inadequate to describe the anisotropic behavior of bones. The vibration analysis techniques are showing potential as clinical tools, and collaboration within the European community is directed towards a correlation between invasive and noninvasive methods of fracture monitoring.     

Stiffness Analysis of Cardiac Electrophysiological Models

The electrophysiology in a cardiac cell can be modeled as a system of ordinary differential equations (ODEs). The efficient solution of these systems is important because they must be solved many times as sub-problems of tissue- or organ-level simulations of cardiac electrophysiology. The wide variety of existing cardiac cell models encompasses many different properties, including the complexity of the model and the degree of stiffness. Accordingly, no single numerical method can be expected to be the most efficient for every model. In this article, we study the stiffness properties of a range of cardiac cell models and discuss the implications for their numerical solution. This analysis allows us to select or design numerical methods that are highly effective for a given model and hence outperform commonly used methods.     

Passive Stiffness of Coupled Wrist and Forearm Rotations

Coordinated movement requires that the neuromuscular system account and compensate for movement dynamics. One particularly complex aspect of movement dynamics is the interaction that occurs between degrees of freedom (DOF), which may be caused by inertia, damping, and/or stiffness. During wrist rotations, the two DOF of the wrist (flexion–extension and radial–ulnar deviation, FE and RUD) are coupled through interaction torques arising from passive joint stiffness. One important unanswered question is whether the DOF of the forearm (pronation–supination, PS) is coupled to the two DOF of the wrist. Answering this question, and understanding the dynamics of wrist and forearm rotations in general, requires knowledge of the stiffness encountered during rotations involving all three DOF (PS, FE, and RUD). Here we present the first-ever measurement of the passive stiffness encountered during simultaneous wrist and forearm rotations. Using a wrist and forearm robot, we measured coupled wrist and forearm stiffness in 10 subjects and present it as a 3-by-3 stiffness matrix. This measurement of passive wrist and forearm stiffness will enable future studies investigating the dynamics of wrist and forearm rotations, exposing the dynamics for which the neuromuscular system must plan and compensate during movements involving the wrist and forearm.     

Boundary Stiffness Regulates Fibroblast Behavior in Collagen Gels

Recent studies have illustrated the profound dependence of cellular behavior on the stiffness of 2D culture substrates. The goal of this study was to develop a method to alter the stiffness cells experience in a standard 3D collagen gel model without affecting the physiochemical properties of the extracellular matrix. A device was developed utilizing compliant anchors (0.048–0.64 N m⁻¹) to tune the boundary stiffness of suspended collagen gels in between the commonly utilized free and fixed conditions (zero and infinite stiffness boundary stiffness). We demonstrate the principle of operation with finite element analyses and a wide range of experimental studies. In all cases, boundary stiffness has a strong influence on cell behavior, most notably eliciting higher basal tension and activated force (in response to KCl) and more pronounced remodeling of the collagen matrix at higher boundary stiffness levels. Measured equibiaxial forces for gels seeded with 3 million human foreskin fibroblasts range from 0.05 to 1 mN increasing monotonically with boundary stiffness. Estimated force per cell ranges from 17 to 100 nN utilizing representative volume element analysis. This device provides a valuable tool to independently study the effect of the mechanical environment of the cell in a 3D collagen matrix.     

Stiffness mapping of lower leg muscles during passive dorsiflexion

It is challenging to differentiate the mechanical properties of synergist muscles in vivo. Shear wave elastography can be used to quantify the shear modulus (i.e. an index of stiffness) of a specific muscle. This study assessed the passive behavior of lower leg muscles during passive dorsiflexion performed with the knee fully extended (experiment 1, n = 22) or with the knee flexed at 90° (experiment 2, n = 20). The shear modulus measurements were repeated twice during experiment 1 to assess the inter‐day reliability. During both experiments, the shear modulus of the following plantar flexors was randomly measured: gastrocnemii medialis (GM) and lateralis (GL), soleus (SOL), peroneus longus (PL), and the deep muscles flexor digitorum longus (FDL), flexor hallucis longus (FHL), tibialis posterior (TP). Two antagonist muscles tibialis anterior (TA), and extensor digitorum longus (EDL) were also recorded. Measurements were performed in different proximo‐distal regions for GM, GL and SOL. Inter‐day reliability was adequate for all muscles (coefficient of variation < 15%), except for TP. In experiment 1, GM exhibited the highest shear modulus at 80% of the maximal range of motion (128.5 ± 27.3 kPa) and was followed by GL (67.1 ± 24.1 kPa). In experiment 2, SOL exhibited the highest shear modulus (55.1 ± 18.0 kPa). The highest values of shear modulus were found for the distal locations of both the GM (80% of participants in experiment 1) and the SOL (100% of participants in experiment 2). For both experiments, deep muscles and PL exhibited low levels of stiffness during the stretch in young asymptomatic adults, which was unknown until now. These results provide a deeper understanding of passive mechanical properties and the distribution of stiffness between and within the plantar flexor muscles during stretching between them and thus could be relevant to study the effects of aging, disease progression, and rehabilitation on stiffness.     

Ankle Bracing and the Neuromuscular Factors Influencing Joint Stiffness

Context:

Health care professionals commonly prescribe external stabilization to decrease the incidence and severity of ankle sprains. The mechanism for this decrease is not clearly understood. Examining the effects of ankle bracing on biomechanical stability and influencing factors may provide important information regarding the neuromuscular effects of bracing.

Objective:

To study the effects of 2 different ankle braces on the neuromuscular factors influencing ankle stiffness.

Design:

Mixed-model repeated-measures design.

Setting:

Research laboratory.

Patients or Other Participants:

Twenty-eight physically active participants composing 2 groups: 14 with unilateral functional ankle instability (age  =  26.19 ± 6.46 years, height  =  166.07 ± 12.90 cm, mass  =  69.90 ± 13.46 kg) and 14 with bilaterally stable ankles (age  =  23.76 ± 5.82 years, height  =  174.00 ± 11.67 cm, mass  =  68.60 ± 13.12 kg).

Intervention(s):

Participants were fitted with surface electromyography electrodes over the peroneus longus, peroneus brevis, tibialis anterior, and soleus muscles. Each participant received transient motion oscillations to his or her ankle on a custom-built medial-lateral swaying cradle in each of 3 conditions: no ankle brace (NB), lace-up brace (LU), and semirigid brace (SR).

Main Outcome Measure(s):

Ankle stiffness as measured by the cradle and preactivation levels (percentage of maximal voluntary isometric contraction) of the 4 test muscles.

Results:

Stiffness levels increased across brace conditions (NB  =  24.79 ± 6.59 Nm/rad, LU  =  28.29 ± 7.05 Nm/rad, SR  =  33.22 ± 8.78 Nm/rad; F_2,52  =  66.185, P < .001). No differences were found between groups for rotational stiffness (stable  =  27.36 ± 6.17 Nm/rad, unstable  =  30.18 ± 8.21 Nm/rad; F_1,26  =  1.084, P  =  .307). Preactivation levels did not change for any of the tested muscles with the application of an ankle brace (F_2,52  =  1.326, P  =  .275).

Conclusions:

The increase in ankle rotational stiffness with the addition of an ankle brace and the lack of any demonstrable neuromuscular changes suggested ankle braces passively contributed to the stability of the system.