护踝类型对落地时下肢运动学的影响：Meta分析和系统评价

目的 系统评估护踝对运动员和普通大学生落地时踝关节运动生物力学的影响,为不同运动水平人群选择护踝提供理论依据。方法 以（“护踝”或“踝关节支撑”）和（“落地”或“起跳”）和（“生物力学”或“运动学”或“动力学”或“肌电”或“神经肌肉”）为主题在CNKI、万方等数据库进行检索;以“(ankle brace OR ankle braces OR ankle bracing OR ankle support) AND (landing OR land OR jump OR hopped OR hopping) AND (biomechanics OR kinematics OR kinetics OR electromyography OR neuromuscular)”为英文检索策略,检索Web of science、EBSCO、PubMed等数据库,检索期限为2000年1月~2020年12月。选用Cochrane偏倚风险评估工具对纳入文献进行质量评价,采用Meta分析中的亚组分析确定不同类型护踝对踝关节运动学的影响。结果 共13项研究、222名受试者纳入Meta分析。对于运动员,两种护踝均可减少踝关节内翻（弹性护踝：26.7%,SMD=-1.647,P=0.040;半刚性护踝：25.8%,SMD=-0.562,P＜0.001）,但仅弹性护踝可减少踝关节跖屈8.4%（SMD=-3.42,P=0.021）。对于普通大学生,两种护踝均可减小踝关节内翻（弹性护踝：35.4%,SMD=-1.000,P=0.013;半刚性护踝：31.1%,SMD=-0.881,P＜0.001）、跖屈（弹性护踝：23.3%,SMD=-1.381,P＜0.001;半刚性护踝：36.3%,SMD=-1.605,P＜0.001）。结论 两种护踝对有5年以上训练史的业余篮球、排球、跑步运动员均有一定的预防作用,弹性护踝可以限制落地时踝关节内翻和跖屈,而半刚性护踝只能限制踝关节内翻,故弹性护踝的预防效果更好。对于无任何训练背景的普通大学生,两种护踝均可限制踝关节内翻和跖屈,其中弹性护踝对内翻限制更大,半刚性护踝对跖屈限制更明显。因此,若普通大学生有跟腓韧带损伤史,优先考虑选用弹性护踝;有距腓前韧带损伤史的普通大学生,     

踝关节扭伤防护及其康复研究进展

踝关节扭伤是临床最常见的外科损伤之一。阐述足踝部解剖结构,重点回顾踝关节运动过程中韧带的生物力学状态。同时,分析踝关节扭伤机制,归纳目前踝关节扭伤预防和康复的主要手段,并着重介绍踝护具预防踝关节扭伤的使用及研究进展。进而归纳踝护具的分类及特点,对踝关节扭伤的预防和踝护具的发展进行展望。踝关节外侧韧带损伤的多发性源于踝关节生理结构的内外侧差异,踝护具的改进及新型踝护具的开发应考虑此结构特点。佩戴踝护具对踝关节扭伤防护具有积极意义,在临床康复方面具有缩短康复时间和避免再次受伤的作用。对于踝关节严重扭伤的康复,半刚性护踝比弹性护踝效果更好。     

模拟跳伞着陆中踝关节防护对下肢肌电活动性的影响

目的研究踝关节外固定防护在模拟半蹲式跳伞着陆中对下肢肌电(Electromyogram,EMG)活动性的影响及其性别差异。方法男女各8名健康成人受试者从0.72m高平台跳落,模拟半蹲式跳伞着陆。实验状态分赤足对照、佩戴护踝和绷带3组。测量其胫骨前肌、外侧腓肠肌、股直肌和股二头肌的肌电图。使用二因素方差分析评价防护和性别对EMG参数的影响。结果使用护踝显著增加男性胫骨前肌触地前EMG幅值(赤足对照:266μV;绷带:368μV;护踝:552μV),防护对其他EMG参数无显著性影响。结论使用护踝仅对男性跳伞者有显著的防护作用;踝关节防护对膝关节EMG活动性无显著性影响。     

踝关节内翻防护型半刚性踝护具的力学特征

目的为探究踝关节易内翻扭伤的机制,设计一款适用于人体踝关节非对称生理结构、可有效防护内翻的踝护具。方法分析导致踝关节内翻的解剖学因素,基于踝关节解剖的非对称结构,构思一种非对称结构踝护具。运用Kinect系统及Geomagic Studio软件,对成年男子踝关节进行三维扫描并数字建模,通过3D打印技术建立踝关节模型。以EVA膜、硅胶膜和裹边紫铜网为原材料,采用立体裁剪及复合材料加工技术,制备两种非对称结构的踝护具。对踝护具的塑形性能、拉伸性能、疲劳性能、外衬面料透气性和摩擦性等进行表征。结果非对称结构踝护具的外侧具有良好的塑形性能,拉伸弹性回复率低。在小应力长时间作用下,EVA复合材料和硅胶膜复合材料均能保持较好的弹性回复,可有效承受内翻外力。外衬面料的透气性和摩擦性试验结果表明,针织涤纶面料较适合作为外衬材料。结论所设计制备的非对称结构踝护具的力学性能可满足踝关节内翻防护要求。外覆面料可提高踝护具的吸湿透气性能,摩擦性能较好。     

踝护具的改进与踝关节周围韧带解剖学特点的关系研究

目的分析踝关节周围韧带的解剖生理特点,并结合踝关节骨性结构特点,对现有踝护具的设计提出改进意见,以增进踝护具在球类、运动体操类等运动项目中对运动员踝关节损伤的防护作用。方法解剖13例26侧经10%甲醛防腐固定的正常踝关节大体标本,暴露其周围韧带,分别观察内外侧韧带的形态,采集相关数据包括韧带的长度、宽度和厚度(宽度及厚度取起点、中点及止点3点之均数),并进行统计学分析。结果经计算踝关节内外侧各韧带长度、宽度、及厚度的x±s(min～max),可见踝关节内侧韧带较外侧韧带宽厚,故踝关节处于外翻状态时韧带的对抗作用较踝关节处于内翻状态时强,因此运动状态下踝关节处于跖屈伴内翻位置时最易受损。结论结合踝关节生理特点及当前市场主流踝护具的特点,笔者考虑弹性踝护具较半刚性踝护具更适用于踝关节运动型损伤的防护,其设计上建议在传统袜套式护具外加上缠绕束带以增强其稳固性,尤其应注意对内踝的缠绕加压以限制踝关节过度内翻。     

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。     

关节镜辅助下Suture-button弹性固定治疗高位踝关节扭伤

背景：高位踝关节扭伤容易漏诊导致踝关节功能障碍，关节镜检查可发现隐匿性高位踝关节扭伤，采用Suture-button弹性固定能恢复远端胫腓联合的生物力学稳定性。目的：探讨踝关节镜辅助下采用Suture-button弹性固定治疗高位踝关节扭伤的临床疗效。方法：回顾性分析2019年8月至2021年8月武汉市第四医院足踝外科在踝关节镜辅助下进行Suture-button弹性固定治疗的40例高位踝关节扭伤患者的病历资料。所有患者均采用Suture-button弹性固定，记录患者术前及术后末次随访美国矫形外科足踝协会踝-后足功能评分、目测类比疼痛评分、踝关节活动度，将患者术前影像学数据与术中关节镜下分离程度进行相关性分析，按照Meislin标准进行疗效评估并记录术后并发症发生情况。结果与结论：(1)40例患者术后获16-48个月随访；(2)术后末次随访美国矫形外科足踝协会踝-后足功能评分为(88.95±6.64)分，目测类比评分为(1.78±1.23)分，踝背伸活动度为(33.50±5.79)°，踝跖屈活动度为(34.50±5.97)°，与术前相比差异均有显著性意义(P <0.05)；(3...     

踝关节不同应力位的动态足底压力特征

目的探究踝关节不同侧肢体和应力位的足底压力分布特点。方法 23名健康受试者通过简易定制走道和足底压力测试平板进行踝中立位、踝内翻、踝外翻的足底压力测试,测试指标为峰值压强、接触面积、接触时间百分比、足底内侧峰值压强之和与外侧峰值压强之和的比值(M/L)、足趾峰值压强之和与足跟峰值压强的比值(A/P)。结果优势腿在第1跖骨的峰值压强明显大于非优势侧,第5跖骨峰值压强明显小于非优势侧。优势侧M/L显著大于非优势侧。除中足、第1趾,其余区域3种应力位的峰值压强存在显著性差异。内翻时各区域的接触时间百分比均大于中立时,外翻时除第2趾其余区域的接触时间百分比大于中立时。内翻、中立、外翻M/L分别为1.24±0.46、1.06±0.26、0.88±0.25;内翻时优势侧M/L大于非优势侧;内、外翻时A/P均大于中立。结论优势侧踝关节稳定性优于非优势侧。踝关节内翻、外翻时稳定性有所下降。内翻时身体往前、内侧偏移,外翻时则往前、外侧偏移以维持稳定。     

负重对行军士兵下肢步态特征的影响

目的评定负重行军对下肢步态产生的影响。方法采用随机交互设计,15名健康男性受试者进行4次步行,作训着装0、7.5、27、50kg,分别采用Vicon运动捕捉系统和AMTI测力台检测髋部、膝部和踝部运动学参数的变化。结果随着负重增加,周期性步频相对增加,步幅减小,基本上维持在恒定速度;左右髋关节屈角峰值、外旋角度峰值以及左右膝关节内收峰值受到影响较为明显,但关节运动幅度能够维持。左踝关节内翻角度峰值以及右踝关节外翻角度峰值同样受到影响;下肢左右膝、踝关节的力和力矩增加。结论在既定负荷范围内,负重增加,整体上下肢关节变化较为稳定,但下肢负荷增加,可潜在增加下肢损伤的风险。     

老年人下楼梯下肢关节做功模式分析

目的 探究下楼梯行走过程中老龄化对老年人下肢关节做功模式的影响,丰富楼梯行走的防跌倒理论。 方法 采用 Vicon 红外运动捕捉系统和 Kistler 三维测力台同步采集青年人和老年人下楼梯行走的运动学和动力学数据,利用下肢关节角度、力矩、功率、做功贡献度指标对下肢关节做功模式进行量化评定。 结果 下楼梯过程中,青 年组和老年组下肢三关节角度、力矩、功率的变化趋势一致。 在优势腿的 1 个支撑相内,老年人的屈髋力矩峰值、伸膝力矩第 1 峰值、第 2 峰值、跖屈力矩第 1 峰值、膝负功率第 1 峰值、第 2 峰值、踝负功率峰值以及髋、膝、踝关节净功均显著降低(P<0. 05);伸髋力矩峰值、髋负功率峰值、踝关节做功贡献度显著增加(P<0. 05),髋、膝关节做功贡献度并未出现显著性差异(P>0. 05)。 结论 在下楼梯过程中,老年人下肢关节力学特征显著降低。 老年人采取不同于青年人的下肢关节做功模式。 老年人通过较大的伸髋姿势抵制躯干的过度前倾,同时采取踝关节做功的代偿模式,提高下楼梯行走的身体稳定性。 建议老年人在锻炼时应以增加膝、踝关节肌肉力量的项目为主,以维持下楼梯的姿势控制能力。     

Lower extremity kinematics and ground reaction forces after prophylactic lace-up ankle bracing

CONTEXT: Long-term effects of ankle bracing on lower extremity kinematics and kinetics are unknown. Ankle motion restriction may negatively affect the body's ability to attenuate ground reaction forces (GRFs). OBJECTIVE: To evaluate the immediate and long-term effects of ankle bracing on lower extremity kinematics and GRFs during a jump landing. DESIGN: Experimental mixed model (2 [group] x 2 [brace] x 2 [time]) with repeated measures. SETTING: Sports medicine research laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 37 healthy subjects were assigned randomly to either the intervention (n = 11 men, 8 women; age = 19.63 +/- 0.72 years, height = 176.05 +/- 10.58 cm, mass = 71.50 +/- 13.15 kg) or control group (n = 11 men, 7 women; age = 19.94 +/- 1.44 years, height = 179.15 +/- 8.81 cm, mass = 74.10 +/- 10.33 kg). INTERVENTION(S): The intervention group wore braces on both ankles and the control group did not wear braces during all recreational activities for an 8-week period. MAIN OUTCOME MEASURE(S): Initial ground contact angles, maximum joint angles, time to reach maximum joint angles, and joint range of motion for sagittal-plane knee and ankle motion were measured during a jump-landing task. Peak vertical GRF and the time to reach peak vertical GRF were assessed also. RESULTS: While participants were wearing the brace, ankle plantar flexion at initial ground contact (brace = 35 degrees +/- 13 degrees , no brace = 38 degrees +/- 15 degrees , P = .024), maximum dorsiflexion (brace = 21 degrees +/- 7 degrees , no brace = 22 degrees +/- 6 degrees , P = .04), dorsiflexion range of motion (brace = 56 degrees +/- 14 degrees , no brace = 59 degrees +/- 16 degrees , P = .001), and knee flexion range of motion (brace = 79 degrees +/- 16 degrees , no brace = 82 degrees +/- 16 degrees , P = .036) decreased, whereas knee flexion at initial ground contact increased (brace = 12 degrees +/- 9 degrees , no brace = 9 degrees +/- 9 degrees , P = .0001). Wearing the brace for 8 weeks did not affect any of the outcome measures, and the brace caused no changes in vertical GRFs (P > .05). CONCLUSIONS: Although ankle sagittal-plane motion was restricted with the brace, knee flexion upon landing increased and peak vertical GRF did not change. The type of lace-up brace used in this study appeared to restrict ankle motion without increasing knee extension or vertical GRFs and without changing kinematics or kinetics over time.     

Ankle bracing, plantar-flexion angle, and ankle muscle latencies during inversion stress in healthy participants

CONTEXT: Ankle braces may enhance ankle joint proprioception, which in turn may affect reflexive ankle muscle activity during a perturbation. Despite the common occurrence of plantar-flexion inversion ankle injuries, authors of previous studies of ankle muscle latencies have focused on inversion stresses only. OBJECTIVE: To examine the latency of the peroneus longus (PL), peroneus brevis (PB), and tibialis anterior (TA) muscles in response to various degrees of combined plantar-flexion and inversion stresses in braced and unbraced asymptomatic ankles. DESIGN: Repeated measures. SETTING: University biomechanics laboratory. PATIENTS OR OTHER PARTICIPANTS: Twenty-eight healthy females and 12 healthy males (n = 40: mean age = 23.63 years, range = 19 to 30 years; height = 172.75 +/- 7.96 cm; mass = 65.53 +/- 12.0 kg). INTERVENTION(S): Participants were tested under 2 conditions: wearing and not wearing an Active Ankle T1 brace while dropping from a custom-made platform into 10 degrees , 20 degrees , and 30 degrees of plantar flexion and 30 degrees of inversion. MAIN OUTCOME MEASURE(S): The time between platform drop and the onset of PL, PB, and TA electromyographic activity was measured to determine latencies. We calculated a series of 2-way analyses of variance to determine if latencies were different between the conditions (braced and unbraced) and among the plantar-flexion angles (alpha = .05). RESULTS: No interaction was found between condition and plantar-flexion angle. No significant main effects were found for condition or plantar-flexion angle. Overall means for braced and unbraced conditions were not significantly different for each muscle tested. Overall means for angle for the PL, PB, and TA were not significantly different. CONCLUSIONS: Reflexive activity of the PL, PB, or TA was unaffected by the amount of plantar flexion or by wearing an Active Ankle T1 brace during an unanticipated plantar-flexion inversion perturbation.     

Ankle ranges of motion during extended activity periods while taped and braced

Tape has traditionally been used to support the ankle during activity. More recently, commercial ankle braces have been worn as an alternative. The cumulative information on the effects of taped versus braced ankle support or interbrace comparisons is inconclusive. With few exceptions, ankle brace studies have collected data soon after support conditions were administered. Plantar-dorsiflexion and inversion-eversion ranges of motion (ROM) of 30 subjects were compared under conditions of unsupported, nonelastic adhesivetaped, and Swede-O and Sub Talar Support-braced ankles. We recorded measurements before activity and after periods of 15, 30, 45, and 60 minutes of selected activity on a motorized treadmill. All support conditions significantly reduced preactivity ROM in all directions compared to unsupported ankles. Results showed that the ankle significantly increased in plantarflexion ROM 15 minutes after the initiation of activity with tape or the SubTalar Support-brace, and after 30 minutes with the Swede-O brace. Tape showed further significant increases in plantarflexion ROM after 15-minute intervals of 30, 45, and 60 minutes of activity. All three support conditions had increased significantly in inversion ROM by 15 minutes of activity. The SubTalar Support brace showed a further significant inversion ROM increase between 15 and 30 minutes postactivity. We conclude that the Swede-O and SubTalar Support braces and tape offer significant preactivity ankle support in all four directions of movement. We also conclude that both braces offer longer postactivity support than tape. In inversion ROM and plantarflexion ROM, actions prevalent in ankle sprains, the Swede-O brace retained support longer than the SubTalar Support brace.     

Prophylactic ankle braces and knee varus-valgus and internal-external rotation torque

Context: Although prophylactic ankle bracing has been shown to be effective in reducing the incidence of ankle sprains,how these ankle braces might affect the other joints of the lower extremity is not clearly understood.Objective: To determine the effects of a prophylactic ankle brace on knee joint varus-valgus and internal-external rotation torque during a drop landing onto a slanted surface.Design: A repeated-measures design.Setting: Biomechanics research laboratory. Patients or Other Participants: Twenty-four physically active college students.Intervention(s): Participants were tested in a brace and no brace condition. Main Outcome Measure(s): We measured 3 dependent variables:(1) peak ankle inversion-eversion torque, (2) peak knee varus-valgus torque, and (3) peak knee internal-external rotation torque. A force plate was used to collect ground reaction force data, and 6 motion analysis cameras collected kinematic data during the unilateral drop landing. An adjustable bar was hung from the ceiling, and a slant board was positioned over the center of the force plate, so that the ankle of the participant's dominant leg would invert upon landing. Peak torque was measure din both the brace and no-brace conditions. The average of the peak values in 3 trials for both conditions was used for the statistical analysis.Results: Ankle eversion torque was significantly greater in the brace condition (F1,23 19.75, P < .01). Knee external rotation torque was significantly greater in the brace condition(F1,23 4.33, P <.05). Valgus knee torque was smaller in the brace condition, but the difference was not statistically significant(F1,23 3.45, P .08).Conclusions: This study provides an important first step in understanding the effects of prophylactic ankle bracing on other joints of the lower extremity. We found that prophylactic ankle bracing did have an effect on knee torque when the subject was landing on a slanted surface. Specifically, knee external rotation torque increased when the ankle was braced.     

Eccentric plantar-flexor torque deficits in participants with functional ankle instability

CONTEXT: Inversion ankle sprains can lead to a chronic condition called functional ankle instability (FAI). Limited research has been reported regarding isokinetic measures for the plantar flexors and dorsiflexors of the ankle. OBJECTIVE: To examine the isokinetic eccentric torque measures of the ankle musculature in participants with stable ankles and participants with functionally unstable ankles during inversion, eversion, plantar flexion, and dorsiflexion. DESIGN: Case-control study. SETTING: Athletic training research laboratory. PATIENTS OR OTHER PARTICIPANTS: Twenty participants with a history of "giving way" were included in the FAI group. Inclusion criteria for the FAI group included a history of at least 1 ankle sprain and repeated episodes of giving way. Twenty participants with no prior history of ankle injury were included in the control group. INTERVENTION(S): Isokinetic eccentric torque was assessed in each participant. MAIN OUTCOME MEASURE(S): Isokinetic eccentric testing was conducted for inversion-eversion and plantar-flexion-dorsiflexion movements. Peak torque values were standardized to each participant's body weight. The average of the 3 trials for each direction was used for statistical analysis. RESULTS: A significant side-by-group interaction was noted for eccentric plantar flexion torque (P < .01). Follow-up t tests revealed a significant difference between the FAI limb in the FAI group and the matched limb in the control group. Additionally, a significant difference was seen between the sides of the control group (P = .03). No significant interactions were identified for eccentric inversion, eversion, or dorsiflexion torques (P > .05). CONCLUSIONS: A deficit in plantar flexion torque was identified in the functionally unstable ankles. No deficits were identified for inversion, eversion, or dorsiflexion torque. Therefore, eccentric plantar flexion strength may be an important contributing factor to functional ankle instability.     

Foot Posture and Plantar Loading With Ankle Bracing

ContextArch height is one important aspect of foot posture. An estimated 20% of the population has pes planus and 20% has pes cavus. These abnormal foot postures can alter lower extremity kinematics and plantar loading and contribute to injury risk. Ankle bracing is commonly used in sport to prevent these injuries, but no researchers have examined the effects of ankle bracing on plantar loading.ObjectiveTo evaluate the effects of ankle braces on plantar loading during athletic tasks.DesignCross-sectional study.SettingLaboratory.Patients or Other ParticipantsA total of 36 participants (11 men, 25 women; age = 23.1 ± 2.5 years, height = 1.72 ± 0.09 m, mass = 66.3 ± 14.7 kg) were recruited for this study.Intervention(s)Participants completed walking, running, and cutting tasks in 3 bracing conditions: no brace, lace-up ankle-support brace, and semirigid brace.Main Outcome Measure(s)We analyzed the plantar-loading variables of contact area, maximum force, and force-time integral for 2 midfoot and 3 forefoot regions and assessed the displacement of the center of pressure. A 3 × 3 mixed-model repeated-measures analysis of variance was used to determine the effects of brace and foot type (α = .05).ResultsFoot type affected force measures in the middle (P range = .003–.047) and the medial side of the foot (P range = .004–.04) in all tasks. Brace type affected contact area in the medial midfoot during walking (P = .005) and cutting (P = .01) tasks, maximum force in the medial and lateral midfoot during all tasks (P < .001), and force-time integral in the medial midfoot during all tasks (P < .001). Portions of the center-of-pressure displacement were affected by brace wear in both the medial-lateral and anterior-posterior directions (P range = .001–.049).ConclusionsAnkle braces can be worn to redistribute plantar loading. Additional research should be done to evaluate their effectiveness in injury prevention.     

How accurate are lockable orthotic knee braces? An objective gait analysis study

There has been an increasing use of orthotic knee braces in the management of knee injuries but, to our knowledge, there is no gait analysis study assessing the accuracy of these braces. Eight healthy male subjects were studied to determine the accuracy of immobilisation or splintage provided by a lockable orthotic knee brace using gait analysis. Six types of immobilisation were studied: locked at 0, 10, 20, 30° and unlocked in an orthotic knee brace, and without a brace. The knee flexion angles measured using the kinematic instruments at 0 and 10° were significantly greater than those set at the knee brace. The knee flexion angle measured using the unlocked knee brace was significantly greater than that measured in the absence of a brace. This study highlights inaccuracies in a knee brace at low knee flexion angles. The higher actual angles alter the biomechanics of the knee joint and result in greater forces across the knee joint and especially the extensor mechanism.     

Biomechanical Comparison of 3 Ankle Braces With and Without Free Rotation in the Sagittal Plane

Context:

Various designs of braces including hinged and nonhinged models are used to provide external support of the ankle. Hinged ankle braces supposedly allow almost free dorsiflexion and plantar flexion of the foot in the sagittal plane. It is unclear, however, whether this additional degree of freedom affects the stabilizing effect of the brace in the other planes of motion.

Objective:

To investigate the dynamic and passive stabilizing effects of 3 ankle braces, 2 hinged models that provide free plantar flexion–dorsiflexion in the sagittal plane and 1 ankle brace without a hinge.

Design:

Crossover study.

Setting:

University Movement Analysis Laboratory.

Patients or Other Participants:

Seventeen healthy volunteers (5 women, 12 men; age = 25.4 ± 4.8 years; height = 180.3 ± 6.5 cm; body mass = 75.5 ± 10.4 kg).

Intervention(s):

We dynamically induced foot inversion on a tilting platform and passively induced foot movements in 6 directions via a custom-built apparatus in 3 brace conditions and a control condition (no brace).

Main Outcome Measure(s):

Maximum inversion was determined dynamically using an in-shoe electrogoniometer. Passively induced maximal joint angles were measured using a torque and angle sensor. We analyzed differences among the 4 ankle-brace conditions (3 braces, 1 control) for each of the dependent variables with Friedman and post hoc tests (P < .05).

Results:

Each ankle brace restricted dynamic foot-inversion movements on the tilting platform as compared with the control condition, whereas only the 2 hinged ankle braces differed from each other, with greater movement restriction caused by the Ankle X model. Passive foot inversion was reduced with all ankle braces. Passive plantar flexion was greater in the hinged models as compared with the nonhinged brace.

Conclusions:

All ankle braces showed stabilizing effects against dynamic and passive foot inversion. Differences between the hinged braces and the nonhinged brace did not appear to be clinically relevant.Key Words: ankle–foot complex, inversion, joint motion, ankle stabilization

Key Points

• Both the hinged and nonhinged braces appeared to sufficiently restrict dynamically and passively induced foot inversion.
• Other than the existence of a hinge, factors related to brace design, material, or application seemed to be responsible for differences in movement restriction.
• The Ankle X brace provided the greatest amount of restriction against dynamic inversion.

With a prevalence of 20%, ankle sprains are the most frequent injuries in athletes and often happen during running and jumping activities,¹ most often during direct contact with an opponent.² Taping and ankle braces are the most advocated interventions to prevent ankle injuries.^1,3–8 Braces differ in design, material, and movement restriction of the ankle-foot joint–complex (eg, semirigid and lace-up braces)^9–11; the goals are to provide sufficient protection but also sufficient flexibility of the ankle during sports and activities of daily living. Consequently, the stabilizing effects of braces need to be evaluated.¹² Semirigid braces use a stirrup design consisting of a thermoplastic material¹³ and are recommended for dynamic conditions, eg, sports, in which the primary goal is to restrict foot inversion but not plantar flexion and dorsiflexion.¹⁰ Therefore, among the semirigid brace models, hinged braces have been designed to allow free rotation in the sagittal plane for almost the entire range of dorsiflexion and plantar flexion of the ankle. However, soft and semirigid braces that allow more plantar flexion were associated with greater inversion velocity on a tilting platform as well as greater amplitude of passively induced inversion.¹⁰ Furthermore, wearing an ankle brace with a subtalar locking system was notably effective in limiting foot inversion during passive as well as dynamic inversion compared with a functional hinged brace and a lace-up brace.¹⁴ Therefore, less-restricted plantar flexion may imply less stabilization in associated foot displacement because it is related to some degree to hindfoot inversion.¹⁵Rapidly induced inversion movements are usually evaluated with tilting platforms or trapdoor mechanisms and may provide information about the stabilizing effect of ankle braces under dynamic loading conditions that simulate inversion trauma.^10,16–18 Passive testing usually involves the application of an external force or moment to the ankle-foot joint–complex so that the stabilizing effect of ankle bracing in other movement directions (plantar flexion, dorsiflexion, eversion, external and internal rotation) can be assessed. These directions are also considered relevant in the evaluation of ankle braces.^10,19 This method does not represent the actual injury mechanism because it lacks the dynamic load application of a real-life trauma situation.¹⁰ However, a high correlation (r = 0.78; P = .0031) was reported¹⁰ between dynamically and passively induced inversion, thus confirming that both methods provide information about various aspects of the stabilizing effects of ankle braces.The aim of our study was to compare the stabilizing effects of 3 ankle braces: 2 hinged models with free rotation in the sagittal plane (Body Armor Embrace [DARCO (Europe) GmbH, Raisting, Germany] and Ankle X [McDavid, Woodridge, IL]) and 1 model without free rotation in the sagittal plane (Aircast AirGo [DJO LLC, Vista, CA]), during a rapidly induced foot-inversion movement on a tilting platform, as well as during passively induced movements in 3 anatomical planes (6 directions) of the ankle-foot joint–complex. We hypothesized that all ankle braces would restrict ankle movements during rapidly induced inversion and passively induced movements of the ankle compared with the unbraced condition. Furthermore, we hypothesized that the hinged braces would provide less stabilization during a rapidly induced inversion and result in larger joint angles during passively induced movements of the ankle and foot compared with the unhinged brace.     

3-PH/R踝关节康复机器人的运动轨迹

目的 研究3-PH/R踝关节康复机器人在不同轨迹下对关节及肌肉受力的影响.方法 分析3-PH/R踝关节康复机器人的运动学原理,将机器人模型简化后导入生物力学建模软件中,以踝关节康复机器人的实际运动轨迹作为模型驱动,比较在跖背屈、内外翻和章动3种不同运动轨迹下关节和肌肉的受力情况,并对3种运动轨迹进行相关性分析.结果 章...