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。     

基于有限状态机控制的智能假肢踝关节

背景：目前智能假肢只是考虑了膝关节的作用,假肢踝关节只是作为假肢膝关节的辅助工具,无法根据外部环境和步态的变化实现假肢自然的行走。 目的：研制出可靠的智能假肢踝关节,有效改善截肢者的步态。 方法：在阻尼可变式踝足假肢的基础上,提出了有限状态机的控制方法,对踝足步态进行了详细的划分,在每个步态内制定了相关的控制策略。 结果与结论：实验结果表明,基于有限状态机控制的智能假肢踝关节能够有效的跟随健肢侧运动,能够适应不同的步速,为以后膝踝协调运动奠定了一定的实验基础。     

偏瘫患者步态特征的动力学仿真分析

目的研究偏瘫步态特征与下肢异常肌力之间的内在关系,阐明导致偏瘫步态的肌力原因并为临床治疗提供建议。方法以偏瘫步态和正常步态为研究对象进行建模仿真,通过正常步态下仿真模型与实测数据对比验证模型有效性,对两种模型的运动学数据、地面反作用力(ground reaction force,GRF)及肌力等特征曲线进行差异分析。结果 LifeMOD仿真结果与测力台实测GRF曲线复相关系数为0.922,动力学模型合理有效。偏瘫步态患者初始着地期胫前肌肌力小导致踝关节背屈不足,摆动前期腓肠肌肌力小,起不到蹬离推动作用。结论胫前肌、腓肠肌软弱无力是偏瘫患者出现足下垂等偏瘫步态特征的主要原因,LifeMOD建模仿真可协助诊断偏瘫患者的异常肌力。     

行走支撑期足平衡的生物力学特征

背景:步行是人体最基本的运动方式,探究行走时足部受力特征和双足差异对深入了解人体行走规律具有重要价值.目的:通过对足平衡曲线的处理和分析,探究人体在步态支撑期各阶段足的功能和行走规律.方法:通过足型筛选出116名具有正常足型的受试者,以自身最适速度行走,记录其足底压力数据,以平均值和1倍标准差绘制归一化处理的足平衡曲线...     

人体足地接触模型的步速适用性

目的构建骨肌多体动力学足地接触模型,研究其适用速度范围。方法采集5名测试者的步态运动数据,以骨肌多体动力学仿真软件Any Body全身模型为基础,建立足地接触模型,分析慢走、正常行走、快走和慢跑不同步态速度下的地面反作用力(ground reaction force,GRF)和地面反作用力矩(ground reaction moment,GRM),并与测力板实验测量值进行对比,分析模型预测精度,获得足地接触模型的适用范围。结果在慢走、正常走和快走(步速0. 69~1. 68 m/s)时,足地接触模型预测能力较高,GRF预测值与实验值相关性大于0. 875,GRM预测值与实验值相关性大于0. 9。结论所开发的足地接触模型同时计算GRF和GRM,可以消除步态分析中对测力板的依赖,能够应用于老年人及病理性步态等低速步态的运动学分析。     

正常人群步行足偏角与年龄特征分析

老年人群由于运动能力退化及受到疾病的影响,容易导致步态异常,而异常步态通常会增加老年人的跌倒风险,带来严重伤害。本文重点对正常无运动功能障碍人群的步态运动学参数进行了研究分析,目的是为了研究不同年龄阶段步态参数的特征,探索步态参数在运动机能评估和临床诊断中的作用。本研究基于电子步道采集步态数据,对足偏角和足间夹角等一系列特征以及这些特征与受试者年龄、性别等因素的相关性进行了定量分析。研究结果表明,大部分受试者正常步行时呈正向步态,足偏角会随着年龄的增长而变大,在中青年期变化缓慢,但进入老年后(>60岁)左足偏角和足间夹角明显升高,变化产生的差异具有统计学意义,研究结果还提示足间夹角是一种普适性强的步态参数。通过本文的研究结果提示,对足偏角进行定量分析有望成为一种对人体下肢运动能力评估及膝关节疾病诊断的便捷、有效的方法。     

梯形瘢痕跟腱瓣治疗瘢痕性足下垂

目的：探索烧伤或外伤后瘢痕挛缩性足下垂的修复方法,改善手术治疗效果.方法：应用梯形瘢痕跟腱瓣治疗瘢痕性足下垂8例13侧,其中4例5侧足内翻严重者同时在内踝下加辅助切口矫正足内翻畸形.临床应用8例13侧,其中火焰烧伤4例,热水泥烧伤2例,化学烧伤1例,外伤1例.结果：8例13侧术后瘢痕跟腱瓣成活,未出现远端坏死;13侧踝关节均达到功能位复位,术后行走无跛行,但踝关节跖屈及背伸仍受限.结论：梯形瘢痕跟腱瓣技术操作简单,血供可靠、安全;小腿后侧瘢痕松解彻底,跟腱充分延长,便于足下垂畸形矫正,是矫治瘢痕挛缩性足下垂可选择的方法.     

锁定型后足融合髓内钉在踝关节融合术中的运用

目的 对锁定型后足融合髓内钉内固定结合自体骨移植术在踝关节融合术中的临床应用疗效进行评价。方法本科于2016年6月至2018年6月收治各类踝关节终末期疾病患者9例,使用踝关节前正中入路暴露踝关节及胫骨远端,截除踝关节各软骨面至软骨下松质骨外露,植入自体髂骨,使踝关节固定于中立位,足跟外翻5°,足外旋5°,使用进口锁定型后足融合髓内钉(SmithNephew)逆行穿钉固定。结果 所有患者随访12～24个月,行踝关节X线检查提示踝关节完全融合。使用AOFAS足踝功能评价系统,对手术前后行走功能、疼痛感、关节活动度等方面进行评价,AOFAS评分由术前(40.60±10.50)分增加至末次随访后(82.60±6.50)分,手术前后对比差异有统计学意义(t=23.25,P0.05)。本组优7例,良2例。结论 锁定型后足融合髓内钉内固定系统融合率高、固定坚强、操作规范简便,可运用于大部分踝关节终末期疾病患者的踝关节融合术。     

步态分析技术评估人工踝关节置换前后踝关节功能的改善程度

背景：人工踝关节置换目前得到了广泛的应用,疗效也得到了一定的认同,但目前的疗效评估多是通过各类评分标准进行评估,但对于踝关节置换后患者步态改变尚缺乏研究。 目的：通过Kofoed评价系统及步态分析技术比较人工踝关节置换患者置换前置换后踝关节功能的改善程度。 方法：收集2007-09/2011-06在上海交通大学医学院附属仁济医院骨科进行人工踝关节置换的患者,对其置换前后行Kofoed评分及步态分析,并与15例正常对照者进行比较,观察置换前后患者踝关节功能的改变。 结果与结论：人工踝关节置换后,Kofoed评分及步态参数步长、步速、患侧单腿支撑时间、双腿支撑时间、患侧踝关节、健侧踝关节、患侧髋关节、患侧膝关节、健侧膝关节行进中关节最大活动度出现明显改善(P < 0.05)。     

Ilizarov技术在儿童烧伤患者足踝畸形治疗中的应用

目的探索Ilizarov技术在瘢痕挛缩致儿童烧伤患者足踝畸形矫正中的应用。 方法2015年6月至2016年6月北京市京都儿童医院烧伤整形外科临床治疗儿童烧伤后瘢痕挛缩致足踝畸形36例(共46只足),应用Ilizarov技术＋矫形手术矫正儿童烧伤后瘢痕挛缩所致足踝畸形。 结果本组手术患者,畸形矫正顺利,瘢痕软化良好,踝关节功能恢复,美国矫形外科足踝协会(AOFAS)踝-后足评分,44只足优(90～100分),2只足良(75～89分)。 结论Ilizarov技术矫治足踝关节畸形,最大程度上减少患者的痛苦,而且避免了植皮手术带来的供皮区的瘢痕增生,使没有良好供皮区的患者关节功能恢复成为可能,为瘢痕挛缩足踝关节畸形的临床治疗开创了一种新的治疗途径。     

有限元法在足踝生物力学研究中的应用进展

有限元法以其高效、精确、可重复利用等特点成为生物力学研究的有效工具。由于足踝部位复杂的解剖结构和运动特性,有限元法可以借助强大的仿真建模和数据计算能力解决真实实验难以解决的问题,具有独特的优势并得到了广泛应用。本文归纳整理了近5年来国内外应用有限元法研究足踝生物力学问题的文献资料,从足踝在不同运动状态下的生物力学分析、组织特性研究、临床治疗分析以及支具与鞋的研究4个方面进行综述,为足踝生物力学的研究提供理论参考,并对未来有限元法在足踝生物力学领域的应用发展提供新思路。     

基于统计形状模型的三维足形状建模

目的构建足的三维统计形状模型(statistical shape model,SSM),揭示足形状的三维变化特征。方法 50名中国青年男性正常足数据用于三维统计形状建模,通过足面网格配准、点对齐及主成分(principal component,PC)降维分析等步骤,获得平均足形态及在各PC维度标准差等参数化的足形态。结果通过PC降维分析,三维足型主要在长短及宽窄(PC1,48.01%)、足弓高度及足背厚度(PC2,11.38%)及大脚趾展收(PC3,7.48%)等维度变化。结论通过构建参数化的足三维SSM,可运用至基于该人群的鞋楦制作、鞋垫定制及临床足病快速诊断等应用。     

行走支撑期足弓变化规律与足功能转换机制

目的 通过分析行走步态参数和足弓力学结构,探究行走支撑期足弓功能的转化机制及变化规律。 方法 利用动作捕捉系统及足底压力测试系统同步采集 8 名受试者不同步速行走时的步态参数及横、纵弓角度。 使用单 因素重复测量方差分析检验不同步速下足横、纵弓角度变化及足底受力的特征值差异。 结果 行走支撑期,纵弓 角度、横弓角度及足底受力曲线均存在两个特征值,3 条曲线特征值在 4 种步速下存在一致性规律。 1. 4 倍和 1. 2 倍最适速度行走时,蹬伸离地阶段时长显著性高于 0. 8 倍最适速度(P<0. 05),横弓升高的拐点和第 1 个受力 峰值出现时间早于 0. 8 倍最适步速(P<0. 05);1. 4 倍最适步速相比于 0. 8 倍最适速度横弓在蹬伸离地阶段的最小 角度显著性增加(P<0. 05),最小角度出现的时间显著性提前(P<0. 05);1. 2 倍最适速度步行时,纵弓第 2 个峰值 出现的位置相比于最适速度提前(P<0. 05)。 结论 行走支撑期,足以纵弓、横弓升降实现功能转化。 足纵弓和足 横弓共同降低完成缓冲,纵弓降低、横弓升高使足增加刚性完成蹬伸。 在执行蹬伸推进功能时,步速增加会加大蹬 伸离地阶段在步态支撑期的时间占比,足横弓和纵弓的变化随蹬伸期提前。 探究足弓变化及足功能转化机制对了 解足部运动规律及足踝康复具有重要的指导意义。     

人体足部生物力学的研究

人体足底压力和剪切力的测量，运动状态下足部各关节、骨和韧带的作用及影响，以及足部生物力学建模和有限元分析是足部生物力学研究的热点，也是足部疾病康复研究的基础。本文对上述三方面的研究作了综述并提出了今后研究的重点。     

脚压测量用传感器

本文讨论了用于脚压测量的四类压力传感器，电阻式传感器、压电式传感器，光电式传感器，电容式传感器介绍了其结构、原理和特点，并分析了几种典型的测量接口电路。     

Generalized Joint Laxity Associated With Increased Medial Foot Loading in Female Athletes

Context:

The relationship between generalized joint laxity and plantar pressure distribution of the foot and the potential implications for lower extremity injury have not been studied.

Objective:

To determine the relationship between generalized joint laxity and dynamic plantar pressure distribution. We hypothesized that individuals with greater generalized joint laxity, or hypermobility, would have greater dynamic medial midfoot pressure and loading during walking than nonhypermobile individuals.

Design:

Case control.

Setting:

Institutional biomechanics laboratory.

Patients or Other Participants:

Participants included 112 female soccer players between 11 and 21 years of age.

Main Outcome Measure(s):

Each participant was tested for generalized joint laxity using the Beighton and Horan Joint Mobility Index (BHJMI; range, 0–9) and was categorized as having either high (BHJMI score ≥4) or low (BHJMI score <4) generalized joint laxity. Peak pressure and maximum force were calculated from a dynamic, barefoot plantar pressure distribution system.

Results:

Peak pressure and maximum force were greater in the 27 participants categorized as having high generalized joint laxity than in the 85 participants categorized as having low generalized joint laxity. The midfoot region exhibited greater loading in participants with high generalized joint laxity than in the other participants. We found an effect of BHJMI classification in the medial midfoot; peak pressure in the dominant (F_1,109  =  11.262, P  =  .001) and nondominant (F_1,109  =  14.32, P < .001) sides and maximum force in the dominant (F_1,109  =  7.88, P  =  .006) and nondominant (F_1,109  =  9.18, P  =  .003) sides were greater in the high generalized joint laxity group than in the low generalized joint laxity group.

Conclusions:

Athletes classified as having high generalized joint laxity demonstrated increased midfoot loading. Delineation of risk factors for medial collapse of the foot, which include hypermobility in athletes, may help clinicians evaluate and prevent lower extremity injury with treatments, such as orthoses.     

Linear and Angular Measurements of the Foot of Modern Humans: A Test of Morton'S Foot Types

In his classic research, Morton established two functionally different configurations of the bipedal and non‐bipedal primate foot: one optimized for stability, with a stiff longitudinal arch and adducted first metatarsal, and the other for compliance. Modern human feet were seen as conforming to the bipedal norm and variation from it as pathology, even though clinical evidence has been clear that variation from the norm of a stiff longitudinal arch or adducted first metatarsal exists. This study aims to document the variation in linear and angular measurements of the foot, using weight‐bearing radiographs of 50 randomly selected people (25 men) from an urban US Level 1 trauma center. The radiographs were obtained to “rule‐out” a foot fracture after trauma or as comparison films for a contralateral foot injury. Measurements were made using Osirix and correlations among the angular and length measurements were determined using Stata with P < 0.05 and Bonferroni correction for multiple comparisons. We found that foot length was not correlated with angular measurements, except for the angle between the first and fifth metatarsal. People with lower medial longitudinal arches also had more abducted first metatarsals and more vertical posterior facets, in accordance with Morton's foot types. Whether or not this variation in modern humans is linked to functionally important consequences remains to be determined in future research. With the new evidence of a more variable foot structure in fossil hominins, understanding the relationship between foot morphology and function becomes more urgent. Anat Rec, 296:1526–1533, 2013. © 2013 Wiley Periodicals, Inc.     

Morphological and Histological Study on the Foot Pads of the Anatolian Bobcat (Lynx lynx)

This study was conducted to reveal the morphometric and morphological features of foot pads in the Anatolian bobcat (Lynx lynx). To achieve this objective, dissection, histological, and radiography techniques were applied to two dead materials obtained from the Republic of Turkey Ministry of Forest and Water Works Sivas Branch Manager. Digit I is radiographically rudimentary in the forepaw. The paws of the forelimb of the Anatolian bobcat have a carpal, a metacarpal, and four digital pads, while the hind feet have a metatarsal pad and four digital pads. The metacarpal pad is cone‐like, while the metatarsal pad resembles a butterfly. The digital pads in the paws of the forelimb are longer and thinner than in the paws in the hind feet. The paws in both feet are situated as binary. Through histological examination, it was determined that the skin of the foot pads consists of epidermis, dermis, and pad cushion. The epidermis is subdivided into basal, spinous, granular, lucidum, and corneum layers. The dermis of each pad consists of papillar and reticular strata containing sweat glands, elastin, collagen, and reticular fibers. Anat Rec, 301:932–938, 2018. © 2017 Wiley Periodicals, Inc.     

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.     

Qualitative Content Analysis of Complementary Topical Therapies Used to Manage Diabetic Foot in Jordan

In order to alleviate diabetic foot problems, patients sometimes seek complementary therapies outside the professional context. This paper describes the use of complementary remedies as a topical treatment for diabetic foot ulcers among Jordanians. Qualitative content analysis was used to analyse written responses of 68 patients with diabetes who have used complementary therapies to treat diabetic foot problems. These 68 persons represented a subgroup of the study population surveyed using a questionnaire, to the effect of investigating diabetic foot treatments provided in Jordan. Informants were recruited from eight healthcare facilities established in the southern part of Jordan plus from one hospital established in the Jordanian capital. The study was approved by the Boards of Ethics of the participating healthcare facilities. Content analysis yielded the category “Complementary Therapies Used”, which included a range of household items (olive oil, sesame oil, honey, and vinegar), and also some indigenous Jordanian herbs (Wormwood, Myrrh, Caper, and Henna among others). The remedies were used either as a monotherapy or as mixtures, to the common goal of treating diabetic foot problems. Other interventions like Al-cowy were also sought from traditional healers. Educational campaigns are required to increase the awareness of patients and their families on possible hazards of unwise complementary therapy use. The decisions on the use of such therapies should be made in agreement with the attending healthcare professionals.