膝骨性关节炎患者与正常青年人步态的对照

背景：应用现代步态分析技术研究膝骨性关节炎患者足底压力分布的报道较少,尚未建立骨性关节炎患者特征性的足底压力数据库。 目的：比较膝骨性关节炎患者与正常青年人步态特征的差异。 方法：运用足底压力测试系统对40例年龄44~70岁膝骨性关节炎患者及10名正常青年人行走时的步态进行测试,观察受试者足底各区域受力时间、单足支撑期参数、步角、足底各分区压力峰值。 结果与结论：膝骨性关节炎患者足底各区域受力时间百分比均高于正常青年组,两组足跟内外侧值差异尤为显著;膝骨性关节炎患者足跟触地阶段时间百分比、前足离地阶段时间百分比低于正常青年组,全足支撑阶段时间百分比高于正常青年组;膝骨性关节炎患者足跟侧部区域压力峰值均较正常青年组降低。说明膝骨性关节炎患者步态指标具有特征性,足跟部触地时间百分比、足跟触地阶段时间百分比、全足支撑阶段时间百分比及前足离地阶段时间百分比均与正常人有明显区别,膝骨性关节炎患者足跟部位外侧肌肉活动和平衡能力控制都较正常年轻人弱。     

基于有限元法对足跟痛在推离期的生物力学研究

基于有限元法对推离期下足跟痛的发病和康复机理进行研究。采集一位足跟痛患者的CT和MRI图像用于三维重建,利用Geomagic软件对得到的模型表面优化,再通过Hypermesh软件对模型进行有限元前处理,最后将得到的下肢有限元模型导入到Abaqus中分析计算,与足底压力板测试结果对比验证模型的有效性,并根据计算结果分析小腿三头肌力的变化对足踝步态推离期生物力学行为特性的影响。结果表明,小腿三头肌肌肉力从550 N增大到1 100 N的过程中,第一趾骨区的峰值压力增大了32.8%,跖骨区的峰值压力增大了14.3%;第一根足底筋膜的应力高达4.69 MPa;跟腱与跟骨连接处和跟骨结节部位的应力峰值分别为28.36和32.79 MPa。由此可见,小腿三头肌挛缩和推离期的绞盘效应会导致足底筋膜过度拉伸,引起跟骨结节处的应力水平提高,使得足部生物力学环境发生变化,从而诱发足底筋膜炎,导致足跟痛。缓解小腿三头肌挛缩、减小肌肉力、避免足底筋膜过度拉伸及降低附着点处的应力水平以恢复足部正常生物力学环境,是治疗足跟痛的主要康复机理。     

部分足截肢部位对步态的影响

目的 部分足截肢是临床截肢手术中最常见的截肢类型,跖趾关节部位、跖骨部位和Lisfrane关节部位是PFA最典型的三种截肢平面,分析经这些平面的部分足截肢对步态的影响,将有助于相关辅具的设计和评价。方法 采用Footscan平板式足底压力测试系统和Optotrak三维运动分析系统,以跨步长、步频、步速、足底各区域的峰值压力、冲量、接触时间、接触面积为特征参量,对这三种截肢平面患者进行了步态分析。结果 分析结果表明,三种不同足部截肢平面中,残足越短,跨步长越小,双足承重时间差越明显;MTP的峰值压力主要在跖骨处和足跟处,TMA和Lisfrane的峰值压力集中在足中部和足跟处。结论 推断在设计和评价不同足部截肢平面的相关辅具时,不同截肢平面辅具有相应差异。     

肥胖男性少年足底动态压力变化参数

背景：青少年肥胖常引发扁平足、足、膝内外翻等症状。 目的：了解13~15岁肥胖男生足底压力参数的分布特点,认识对青少年身体平衡能力等方面所产生的影响。 方法：随机选择长春市东北师范大学附属中学13~15岁的健康在校男生60人,根据体质量指数标准分为18.5~24.9 kg/m²的对照组,25~30 kg/m²的超重组和大于30 kg/m²的肥胖组,各20人。借助比利时footscan足底压力测试系统,分析各组自然行走时足底动态压力分布变化特征。 结果与结论：不同体质量男生的足底垂直力-时间曲线的足跟着地时的冲击峰和足完全放平时出现的谷值出现在步态周期的百分比随体质量的增加而加长;超重组和肥胖组足弓部位的触地时间明显大于对照组,同时足弓和足跟的接触面积百分比增大,而前足的百分比值减小;超重组和肥胖组的足底总峰值压强明显大于对照组,足底总压强与体质量呈正相关,足底的接触面积和体质量之间存在着明显的正相关;除了足跟和第1趾骨外,超重组和肥胖组其他各部位及总的压强变化率均大于对照组。说明超重于肥胖可使男生足底压力发生变化。     

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。     

基于生物力学有限元法的足跟痛发生与康复机制

目的 研究足跟痛病症的发生与康复机制,为临床上足跟痛治疗方法的有效性提供理论依据。方法 对足跟痛患者足膝部CT、MRI影像数据进行三维重建,建立患者足膝部的骨骼-肌肉复合有限元模型。基于所建模型采用有限元方法,仿真模拟小腿肌肉挛缩对足踝部生物力学性能的影响。结果 在小腿肌肉提升力的作用下,足底压力从足跟区向足掌区转移,且不同肌肉作用力组合方案对压力分布不产生明显差异。足底筋膜张力升高,跟骨表面产生应力集中。在240 N作用力下,跟腱附着位置和跟骨结节处产生应力峰值,分别高达10.82、11.2 MPa。结论 小腿部肌肉和跟腱中产生应力集中,会导致足踝部生物力学特性发生变化,引发足跟部疼痛。释放集中应力恢复踝关节中各骨骼和关节的位置,从而改善整体生物力学环境的方法是治疗足跟痛的康复机制。     

有无跌倒史老年人步态生物力学特征对比分析

目的 通过对有、无跌倒史老年人进行步态运动学和动力学同步测量,对比步态生物力学特征,为老年人跌倒预防提供理论及实践依据。 方法 在居民社区及老年公寓招募 284 名 60 岁以上老年人作为测试对象,严格按照纳入和排除标准,按照既往 12 个月跌倒史分为跌倒组(有跌倒史)和非跌倒组(无跌倒史)。 采用三维录像解析和动态足底压力测量获取受试者自然行走步态的运动学和动力学参数。 测试数据采用独立样本 t 检验进行组间各因素差异性对照分析。 结果 跌倒组老年人自然行走步态过程中左足第 1 跖骨峰值力、双足足跟外侧冲量、右足大拇趾冲量等动力学参数与非跌倒组相比,差异均有统计学意义(P<0. 05);跌倒组老年人自然行走步态过程中右足第 2 跖骨受力面积、左足缓冲期接触时间、右足前脚掌触地时间、右足横向压力中心(center of pressure, COP)轨迹、左足触地髋角、双足峰值压力点重心位移等运动学参数与非跌倒组相比,差异均有统计学意义(P<0. 05)。 结论 与无跌倒史老年人相比,有跌倒史老年人行走过程中第 2 跖骨受力面积减小,足底触地时间延长,过渡期支撑稳定性下降,COP 横向位移增大,行进方向 COM 位移减小,意味着老年人下肢肌力下降,足侧向摆动增大,步行推进力减小,可导致姿势控制策略发生代偿性改变,潜在跌倒风险增大。 在临床评估中,应重点关注有跌倒史老年人群步态足底压力及运动学特征。     

老年男性和年轻男性行走时足底动力学特征差异

目的 比较老年男性和年轻男性在行走时足底动力学特征的差异,探讨增龄对足底动力学的影响.方法 应用鞋垫式压力测试系统比较13名老年男性和14名年轻男性在串联行走时左脚的受压时长、受压支撑百分比、开始受压支撑百分比、结束受压支撑百分比、最大压强、最大压强支撑百分比、平均最大压强、时间压强积分、最大压力、最大压力支撑百分比、...     

Influence of patellofemoral pain syndrome on plantar pressure in the foot rollover process during gait

BACKGROUND:

Patellofemoral Pain Syndrome is one of the most common knee disorders among physically active young women. Despite its high incidence, the multifactorial etiology of this disorder is not fully understood.

OBJECTIVES:

To investigate the influence of Patellofemoral Pain Syndrome on plantar pressure distribution during the foot rollover process (i.e., the initial heel contact, midstance and propulsion phases) of the gait.

MATERIALS AND METHODS:

Fifty-seven young adults, including 22 subjects with Patellofemoral Pain Syndrome (30 ± 7 years, 165 ± 9 cm, 63 ± 12 kg) and 35 control subjects (29 ± 7 years, 164 ± 8 cm, 60 ± 11 kg), volunteered for the study. The contact area and peak pressure were evaluated using the Pedar-X system (Novel, Germany) synchronized with ankle sagittal kinematics.

RESULTS:

Subjects with Patellofemoral Pain Syndrome showed a larger contact area over the medial (p = 0.004) and central (p = 0.002) rearfoot at the initial contact phase and a lower peak pressure over the medial forefoot (p = 0.033) during propulsion when compared with control subjects.

CONCLUSIONS:

Patellofemoral Pain Syndrome is related to a foot rollover pattern that is medially directed at the rearfoot during initial heel contact and laterally directed at the forefoot during propulsion. These detected alterations in the foot rollover process during gait may be used to develop clinical interventions using insoles, taping and therapeutic exercise to rehabilitate this dysfunction.     

Biomechanical study of tarsometatarsal joint fusion using finite element analysis

Complications of surgeries in foot and ankle bring patients with severe sufferings. Sufficient understanding of the internal biomechanical information such as stress distribution, contact pressure, and deformation is critical to estimate the effectiveness of surgical treatments and avoid complications. Foot and ankle is an intricate and synergetic system, and localized intervention may alter the functions to the adjacent components. The aim of this study was to estimate biomechanical effects of the TMT joint fusion using comprehensive finite element (FE) analysis. A foot and ankle model consists of 28 bones, 72 ligaments, and plantar fascia with soft tissues embracing all the segments. Kinematic information and ground reaction force during gait were obtained from motion analysis. Three gait instants namely the first peak, second peak and mid-stance were simulated in a normal foot and a foot with TMT joint fusion. It was found that contact pressure on plantar foot increased by 0.42%, 19% and 37%, respectively after TMT fusion compared with normal foot walking. Navico-cuneiform and fifth meta-cuboid joints sustained 27% and 40% increase in contact pressure at second peak, implying potential risk of joint problems such as arthritis. Von Mises stress in the second metatarsal bone increased by 22% at midstance, making it susceptible to stress fracture. This study provides biomechanical information for understanding the possible consequences of TMT joint fusion.     

基于足底压力分布的足部运动特征提取

目的 分析足底压力分布的统计学行为,提取足部运动的特征,为步态识别研究用于医疗临床诊断、康复训练和大众健康等提供参考.方法 通过对采集到的足部压力数据进行预处理,并对数据进行统计分析,实现足迹重构,并对足迹、分割区域以及各区域压力分布率进行比较分析,实现对足部运动特征的分解.结果 分区域对足底压力峰值进行分析比较,以不...     

不同跌倒风险老年人跨越障碍前后足底压力特征

目的 探索不同跌倒风险老年人在跨越障碍前后的步态动力学特征。方法 采用坐-立行走计时测试和5次坐立测试对27名社区老年人进行跌倒风险分级,应用足底压力测量系统对老年人跨越障碍前后的足底压力参数进行测试分析。结果 高、低跌倒风险组老年人在跨越障碍前后整体足底压力双峰曲线特征值组间无显著差异(P>0.05)。高跌倒风险组在跨越障碍后X方向压力中心(center of pressure, COP)运行轨迹显著大于低跌倒风险组(P<0.05)。跨越障碍前,高跌倒风险组支撑足第3跖骨峰值压力大于低跌倒风险组(P<0.05)。在跨越障碍后,高跌倒风险组支撑足第1趾骨峰值压力明显小于低跌倒风险组(P<0.05),而高跌倒风险组足跟外侧冲量明显大于低跌倒风险组(P<0.05)。高、低跌倒风险组老年人在跨越障碍前后足底接触面积分布规律基本一致,各区域接触面积组间均无显著差异(P>0.05)。结论 高跌倒风险老人相对低跌倒风险老年人跨越障碍时支撑时间延长,跨越腿足底跖骨区域峰值压力增加,足底COP曲线表现出不对称性,且在冠状面横向变化范围增大。在临床评估中应重点关注跌倒...     

背向行走足底压力分布特征对平衡能力的影响

目的研究背向行走过程中足底压力的变化,从而探究其对人体步态平衡能力的影响。方法使用足底压力测量系统(Pedar-X压力鞋垫)采集10名受试者在正向和背向两种行走模式下的足底压力数据。试验在跑步机上进行,以正向行走作为对照试验组。依据试验条件及预试验时受试者的直观感受,选取4个速度(2.0、2.5、3.0、3.5 km/h)分别进行两种行走模式下的试验,分析不同速度下足底压力中心轨迹、足底压力、足-地接触时间等参数的变化情况。结果不同速度的两种行走模式下,人在行走过程中的足底压力有所不同。背向行走过程中,足底压力中心从足前部向足跟过渡,从内侧向外侧过渡。相比正向行走,背向行走时的足底压力显著减小,行走过程中的足-地接触时间有所增加。结论研究背向行走的压力分布有助于更全面地理解人的动态平衡机制,并为行走稳定性的相关研究提供新视角。     

A Population of Patient-Specific Adult Acquired Flatfoot Deformity Models Before and After Surgery

Following IRB approval, a cohort of 3-D rigid-body computational models was created from submillimeter MRIs of clinically diagnosed Adult Acquired Flatfoot Deformity patients and employed to investigate postoperative foot/ankle function and surgical effect during single-leg stance. Models were constrained through physiologic joint contact, passive soft-tissue tension, active muscle force, full body weight, and without idealized joints. Models were validated against patient-matched controls using clinically utilized radiographic angle and distance measures and plantar force distributions in the medial forefoot, lateral forefoot, and hindfoot. Each model further predicted changes in strain for the spring ligament, deltoid ligament, and plantar fascia, as well as joint contact loads for three midfoot joints, the talonavicular, navicular-1st cuneiform, and calcaneocuboid. Radiographic agreement ranged across measures, with average absolute deviations of <5° and <4 mm indicating generally good agreement. Postoperative plantar force loading in patients and models was reduced for the medial forefoot and hindfoot concomitant with increases in the lateral forefoot. Model predicted reductions in medial soft-tissue strain and increases in lateral joint contact load were consistent with in vitro observations and elucidate the biomechanical mechanisms of repair. Thus, validated rigid-body models offer promise for the investigation of foot/ankle kinematics and biomechanical behaviors that are difficult to measure in vivo.     

背包类型对大学生楼梯行走运动学和足底压力的影响

目的 分析不同背包类型和载荷对大学生上楼梯行走时运动学和足底压力的影响,为大学生选择合适的背包及携带方式提供参考。方法 采用Nokov红外光点运动捕捉系统和Podomed足底压力测试系统分析15名男大学生上楼梯支撑期内躯干和下肢关节活动范围、峰值时刻下肢运动学参数、足底各分区压力峰值、接触时间、全足最大压强、平均压强等参数的差异。结果 5%BW和10%BW背包载荷会减小躯干旋转活动范围(range of motion, ROM),增加踝关节屈伸和内外翻ROM,10%BW背包载荷下足底第1、3跖骨压力峰值和全足最大压强提升(P<0.05)。单肩包和手提包减小躯干侧倾和旋转ROM,增大了踝关节屈伸ROM、髋关节屈曲角、足弓和足跟内侧压力峰值(P<0.05)。双肩包负重增加足趾区的压力峰值(P<0.05)。结论 楼梯行走时,5%BW和10%BW背包载荷均会限制躯干旋转,增加踝关节ROM,10%BW载荷还会增加足跖区的负荷。单侧负重模式会使躯干向未负重侧倾斜以及向负重侧旋转。携带双肩包时足趾处的压力较高,而单肩包和手提包主要集中增加足弓和足跟内侧压力。建议大学生群体选择对称性...     

外侧楔形鞋垫对足踝生物力学影响的有限元分析

目的 探究外侧楔形鞋垫对足踝内部组织(包括足骨、关节和韧带)的生物力学影响。 方法 建立并验证足踝-鞋垫-地面三维有限元模型,探究步态 3 个关键瞬间赤足模型和鞋垫干预模型的足底压力分布、关节接触压力、跖骨及主要韧带的应力。 结果 5°外侧楔形鞋垫模型足底峰值压力比赤足模型减小 65. 8% 。 鞋垫干预使楔舟关节处峰值接触压力减小;距下关节处峰值接触压力和第 4、5 跖骨处峰值应力增大。 结论 本研究量化评估了外侧楔形鞋垫对足踝各部分的生物力学影响,提出了可适当减小外侧楔形鞋垫第 4、5 跖骨处倾斜角度的设计建议。     

Pseudoganglion on the connecting branch between the deep branch of the lateral plantar nerve and medial plantar nerve

The connecting branch between the deep branch of the lateral plantar nerve and medial plantar nerve often has an enlarged site. We investigated these enlarged sites of the connecting branches. We observed the 22 human feet of 20 Japanese cadavers. We investigated the connecting branch macroscopically and histologically. We found the connecting branches between the deep branch of the lateral plantar nerve and medial plantar nerve in 19 feet out of 22 feet. This connecting nerve branch was interposed between the tendon of the flexor hallucis longus and the flexor hallucis brevis, and there enlarged in the anteroposterior direction. After penetration, numbers of fascicles of this connecting branch were increased at the enlarged site. In this region, the connective tissues surrounding the nerve fascicles and vessels were more developed compared with the adjoining sides of this branch. A few fascicles at this enlarged site innervated the first metatarsophalangeal joint capsule. Other nerve fascicles arose from the connecting branch and branched off muscular branches to the flexor hallucis brevis. This branch possibly receives the physical exertion or friction during gait due to its position. Deformity and overload of the foot can cause sensory disorders of the foot, but the anatomical basis for the relationship between the deformity/overload and sensory disorders of the foot is unclear. We discussed that this connecting branch can be a potential cause of pressure neuropathies in the human foot.     

Botulinum Toxin Type A Injection for Spastic Equinovarus Foot in Children with Spastic Cerebral Palsy: Effects on Gait and Foot Pressure Distribution

PurposeTo investigate the effect of intramuscular Botulinum toxin type A (BoNT-A) injection on gait and dynamic foot pressure distribution in children with spastic cerebral palsy (CP) with dynamic equinovarus foot.ResultsSpasticity of the ankle plantar-flexor in both the MAS and MTS was significantly reduced at both 1 and 4 months after injection. On dynamic foot pressure measurements, the center of pressure index and coronal index, which represent the asymmetrical weight-bearing of the medial and lateral columns of the foot, significantly improved at both 1 and 4 months after injection. The dynamic foot pressure index, total contact area, contact length and hind foot contact width all increased at 1 month after injection, suggesting better heel contact. Ankle kinematic data were significantly improved at both 1 and 4 months after injection, and ankle power generation was significantly increased at 4 months after injection compared to baseline data.ConclusionUsing a computerized gait analysis and foot scan, this study revealed significant benefits of BoNT-A injection into the GCM and TP muscles for dynamic equinovarus foot in children with spastic CP.     

基于最优拉丁超立方设计的糖尿病足鞋垫优化设计

目的 提出一种鞋材弹性模量与厚度联合优化设计糖尿病足鞋垫的方法,以降低足底压力和软组织内部应力。方法 通过逆向工程方法建立足部有限元模型,基于足底压力分布特征划分鞋垫压力区域,采用有限元法对接触力学进行研究,为优化过程中调整不同区域内材料的弹性模量和鞋垫前后足厚度奠定基础,使用最优拉丁超立方设计得到最优参数组合。结果 设计的鞋垫增加约37.55%的足底接触面积,跖骨区和足跟区的压力峰值分别降低15.07%、36.96%,足跟处软组织内部应力降低20.83%,足底筋膜张力降低约60%。结论 所提出的方法可用于设计定制鞋垫,设计的个性化鞋垫具有更大的接触面积和降低糖尿病足底溃疡的良好潜力。     

基于F-Scan三维动态足底压力分析系统的动静态足底压力分析

背景：有研究表明足的部分解剖区域支撑着人体大部分质量,并调节着人体的平衡,测量这些区域的压强峰值及分布即可获取足、下肢乃至全身的生理、结构及功能等方面的大量信息。 目的：观察健康青少年足球运动员自然行走时左右足峰力值、负荷冲量等的动态足底压力分布。 方法：采用三维动态足底压力步态分析系统对16~19岁适龄青少年足球运动员进行动态足底压力测试。 结果与结论：受试者足底应力-时间曲线呈明显的双峰型,足底10个分析区域峰力均值在足跟外侧最大(P < 0.01),右足习惯者第1 趾、第1,2 跖骨、足跟内外侧区域平均峰力值右足大于左足(P < 0.05),而第5跖骨、足弓2个区域平均峰力值左足大于右足(P < 0.05)。受试者行走时整足接触阶段、离地阶段负荷中心在第1、2跖骨、足跟内外侧区域,足部最大负荷部位在第1、2跖骨、足跟内外侧区域,男女左右足分布规律基本一致。结果证实,健康青少年足球运动员左右足动态与静态足底压力分布规律存在一致性特征。