外翻足的足横弓塌陷力学分析

一般而言 ,足横弓是指前足横弓。是由 5个跖骨头和一对籽骨组成的向前向上的横形结构 ,是由强大的足底骨足横弓间韧带和肌肉固定 ,稳定性强 ,同时又有一定弹性缓冲的三维结构。前足负重时 ,承重压力通过对足横弓的诸跖骨头向中央跖骨头传递 ,各跖骨头间距加大 ,足横弓下陷 ,冲击力动能通过足横弓的形变转换成足横弓的弹性形变势能。足横弓弧顶塌陷程度的影响因素有负重重量 ,稳定足横弓的韧带和肌肉强度 ,跖跗关节活动度和负重前足横弓的高度。第 1跖骨头负重的异常改变直接影响维持足横弓稳定的内部因素 ,致足横弓塌陷。外翻是最常影响足…     

正常足步态周期中动及足横弓形态的初步分析

目的：观察正常步态周期中跖骨头平面足横横弓的运动形态,并探讨跖骨头平面足横弓在行走过程中的重要意义。方法：以C臂机观察模拟正常步态周期中跖骨头平面足横弓冠状面的变化形态并以录相机记录,通过视频转换为电脑工作站可以分析的MPGE格式文件,在电脑工作站与C＋ ＋Builder下精确的计时器链接,分析足横弓的变化,结果：得到足横弓塌陷时间与足横弓指数Q：I－II跖间角;I－IV跖间角,个体体重等的关系曲线,结论：跖骨头平面存在由5个跖骨头构成的足横弓,以1,5跖骨头为底,2,3跖骨头为顶,步态周期中,由站立相到推离相时,2,3跖骨头渐渐塌陷,负重份额渐增加,足横弓指数Q与足横弓塌陷时间密切相关,Q值增大,则2,3跖骨头塌陷的时间缩短,第2,3跖骨头就越早负重,在整个步态周期中的负重时间延长,导致过度负重,2,3跖骨头下疼痛性胼胝体形成。     

足横弓形态的动态分析与踇外翻关系研究

目的观察正常步态周期中跖骨头平面足横弓的运动形态 ,探讨跖骨头平面足横弓在行走过程中的重要意义及与外翻的关系。方法正常足 13足,外翻足 12足,应用" C"型臂 X线机观察跖骨头平面足横弓在步态周期中的运动形态、空间位置变化,并用录像机记录。电脑工作站与 C＋＋ Builder下精确的计时器相连接,记录足横弓塌陷时间。结果跖骨头平面存在由五个跖骨头构成的足横弓 ,以第一、五跖骨头为底,第二、三跖骨头为顶;在步态周期中,由站立相到推离相时,第二、三跖骨头逐渐塌陷,负重份额渐增加;足横弓指数 Q与外翻角 (HVA)相关, HVA越大, Q值越小,步态周期中第二、三跖骨头下降到地面的时间越短,第二、三跖骨头就越早负重,负重时间延长,导致其过度负重和第二、三跖骨头下疼痛性胼胝体形成。结论跖骨头平面足横弓在正常步态周期中发挥重要作用,由站立相至推离相,随重心前移,第二、三跖骨头的负重增加,跖骨头下移而与地面接触导致足横弓的塌陷。外翻患者中,足横弓塌陷时间早,跖骨头负重时间长,可以导致前足功能紊乱。     

正常足与踇外翻足的足横弓三维形态比较

运用Ｘ线片、ＣＴ及计算机图像处理技术，了解正常足横弓的三维形态，探讨外翻三维畸形的检测方法。对３２５例正常人和５７例外翻足的足正位Ｘ线片进行测量，检测五个跖骨和籽骨的相对位置关系及两组的异同；对２４例正常足和１６例外翻足进行ＣＴ扫描，经计算机图像处理，观测正常足横弓的冠状面形态和外翻足的足横弓的畸形表现。结果发现：７４．８６％的正常实验对象第一跖骨短于第二跖骨；外翻足的籽骨不随内翻的第一跖骨内移，相对处于稳定的位置；正常人组足横弓指数Ｈ＝０．２０９±０．０５１，第一跖骨旋前角度Ｐ＝８．７５°±１４．６°；第一跖骨籽骨滑车系统功能丧失是外翻足足横弓塌陷的重要原因。     

跖骨全切除前足再造术

跖骨全切除前足再造术陈宝兴ＲｉｔａＲａｅＦｏｎｔｅｎｏｔＤ．Ｐ．Ｍ前言：１９１１年Ｈｏｆｍａｎ首次用跖骨头全切除术治疗由类风湿性关节炎所致的前足畸形。主要包括趾外翻、爪形趾及跖骨头在前足跖面突出。Ｈｏｆｍａｎ首次报告的手术方法是全部切除５个跖骨头，...     

足横弓与外翻关系的研究进展

足横弓的组成与部位 ,目前认识不尽相同。有人认为各跖头站立时完全着地 ,不宜看作足横弓的组成[1] 。但从解剖及生物力学的角度来看 ,各跖头平面横弓在吸收震荡 ,减轻足底应力方面起重要作用。本文主要就跖骨头平面足横弓作讨论。1　足横弓的解剖及维持因素主要由足骨 ,肌肉与韧带。其中第 1、5跖骨不仅是维持足横弓的两块基石 ,也是足纵弓的重要组成因素[1] 。1.1　跗跖关节　属平面关节 ,可作轻微滑动及屈伸运动 ,内外侧的跗跖关节 ,可作轻微的内收、外展运动。主要由跗跖背侧韧带 ,跗跖跖侧韧带 ,楔跖骨间韧带维持。1.2　跖骨间关节　只…     

拇趾外翻足负重位和非负重位下X线测量指标与跖骨头下疼痛的相关性分析

目的：通过拇外翻足负重位和非负重位X线测量指标分析,探讨拇外翻畸形时足弓塌陷程度与跖骨头下疼痛的相关性.方法：对2012年5月至2012年10月120例（240足）拇外翻患者跖骨头下疼痛观察并摄患足负重位和非负重位下X线正侧位片,分别测量拇外翻角（HVA）、1-2跖间角（IM1-2）、1-5跖间角（IM1-5）、内弓顶角和前弓角,比较其负重与非负重位下的差异,并分析其（除HVA）差值与拇外翻畸形、跖骨头下疼痛的相关性.结果：120例拇外翻患者240足中148足存在跖骨头下疼痛,拇外翻足负重位IM1-2、IM 1-5、内弓顶角较非负重位均明显增加,而拇外翻角和前弓角则反之;负重与非负重位下IM1-2、IM1-5、内弓顶角的差值与拇外翻畸形程度及跖骨头下疼痛密切相关.结论：拇外翻足弓塌陷程度随拇外翻畸形的增加而加重,跖骨头下疼痛随着足弓塌陷程度加重而加重.通过足负重、非负重位下X线测量指标分析可评价拇外翻足弓塌陷程度,对防治跖骨头下疼痛有重要意义.     

足横弓与NFEA7外翻关系的研究进展

足横弓的组成与部位,目前认识不尽相同.有人认为各跖头站立时完全着地,不宜看作足横弓的组成[1].但从解剖及生物力学的角度来看,各跖头平面横弓在吸收震荡,减轻足底应力方面起重要作用.本文主要就跖骨头平面足横弓作讨论.     

正常足与Mu外翻足跖骨头下压力与足部负重比例变化的关系

目的：从生物力学角度探讨Mu外翻足前足横弓跖骨头下压力的改变情况。方法：运用本所生物力学室研制的足底压力测试系统，对正常足与Mu外翻足足底压力进行测试，并将结果进行统计分折。结果：随着足部负重比例的增加，Mu外翻足前足中间跖骨头下压力的变化较快，与正常足相比具有显著差异。结论：从生物力学角度证明，正常足前足具有横弓结构，Mu外翻足前足存在横弓塌陷。     

脑瘫性足下垂内翻手术方法的选择

目的：进一步探索脑瘫性足下垂内翻的理想手术方案。方法；回顾性分析31例44足脑瘫足下垂内翻的手术治疗和康复过程。结果：足下垂内翻畸形明显矫正，足跟、第5跖骨头和第1跖骨头触地行走病人25例34足占78％。结论：脑瘫性足下垂内翻采用多种手术治疗效果较好。     

Consequences of partial and total plantar fascia release: a finite element study

BACKGROUND: Plantar fasciotomy, a common operative procedure to relieve chronic heel pain, has been suggested to decrease foot arch stability. A systematic evaluation of the biomechanical consequences of partial or total plantar fascia release is essential to the understanding of the biomechanical rationale behind these operative procedures. METHODS: A geometrical detailed three-dimensional (3-D) finite element (FE) model of the human foot and ankle, incorporating geometrical and contact nonlinearities, was constructed by 3-D reconstruction of MR images. Partial and complete plantar fascia releases were simulated to evaluate the corresponding biomechanical effects on load distribution of the bony, ligamentous, and encapsulated soft-tissue structures. RESULTS: Partial and total plantar fascia release may decrease arch height but did not necessarily cause total collapse of the foot arch even with additional dissection of the long plantar ligament. Operative release of the plantar fascia was compromised by increased strains of the plantar ligaments and intensified stress in the midfoot and metatarsal bones. Load redistribution among the centralized metatarsal bones and focal stress relief at the calcaneal insertion were predicted with different types of fasciotomy. CONCLUSIONS: The FE model suggested that plantar fascia release may provide relief of focal stress and therefore could relieve associated heel pain. However, these operative procedures may pose a risk to arch stability and clinically may produce dorsolateral midfoot pain. The initial strategy for treating plantar fasciitis should be nonoperative. If surgery is necessary, partial release of less than 40% of the fascia is recommended to minimize the effect on arch instability and maintain normal foot biomechanics.     

Evaluation of the transverse metatarsal arch of the foot with gait analysis

BACKGROUND: The existence of the transverse metatarsal arch (TMA) of the foot is a point of controversy. According to Kapandji, TMA of the foot elevates the 2(nd) to 4(th) metatarsal heads. Some authors suggest the existence of TMA, while others suggest that there is no functional metatarsal arch of the foot. In this study, we evaluated the existence of TMA of the foot and weight distribution on the metatarsal heads with the EMED-SF (Novel H, Munich, Germany) plantar pressure analysis system. METHODS: The test was performed with 16 volunteers. According to the three functional columns of the foot, the metatarsal region of pressure picture obtained from the EMED-SF system was divided into three regions called 'masks'. Mean pressures in the masks were calculated at the mid-stance phase. RESULTS: The highest mean pressure recorded was located at the 2nd to 3rd metatarsal heads (7.96 N/cm(2)), and the second highest pressure was at the heel (6.55 N/cm(2)). The pressures of the 1st metatarsal and 4th-5th metatarsal heads were 4.86 and 6.26 N/cm(2), respectively. The difference between the pressure distributions under metatarsal heads was statistically significant ( p=0.000). CONCLUSION: According to our results, TMA of the foot does not exist as described by Kapandji.     

正常足与(*母)外翻足跖骨头下压力与足部负重比例变化的关系

目的 :从生物力学角度探讨外翻足前足横弓跖骨头下压力的改变情况。方法 :运用本所生物力学室研制的足底压力测试系统 ,对正常足与外翻足足底压力进行测试 ,并将结果进行统计分析。结果 :随着足部负重比例的增加 ,外翻足前足中间跖骨头下压力的变化较快 ,与正常足相比具有显著差异。结论 :从生物力学角度证明 ,正常足前足具有横弓结构 ,外翻足前足存在横弓塌陷。     

足横弓重建法治疗外翻

目的 :介绍一种伴有足横弓塌陷的严重外翻的手术方法。方法 :12例伴有足横弓塌陷的严重的外翻足首先经X线、CT检测其三维畸形程度 ,而后手术中采用第一跖骨基底截骨 ,远端外推、下压、外旋以纠正第一跖骨的三维畸形 ,恢复足横弓正常形态 ,矫形位置以克氏针固定 :对外翻角 (HVA)的纠正采用常规第一跖趾关节软组织手术。结果 :术后 3～ 12月随访 ,优 6例、良 4例、中 2例 ,优良率 83 % ,其中 ,前足底中部痛性胼胝均有明显减轻。结论 :足横弓重建手术是严重外翻较好的选择术式。     

The effect of immobilization devices on the load distribution under the foot

The load distribution under the foot was investigated under various conditions by means of pressure-sensitive transducers. Weight-bearing pressures at the first and third metatarsal heads and at the heel were measured while subjects ambulated barefoot and while wearing numerous immobilization devices. The proportion of body weight imposed on the plantar surface of the foot is dependent on the specific gait pattern displayed during barefoot walking. Maximum reduction of forefoot loads was achieved by means of a short-leg walking cast or an ankle boot cast with a posteriorly placed flat rubber heel. A centrally placed rocker heel leads to increased forefoot loads, especially under the first metatarsal head. Casting devices used in conjunction with cast shoes were not as effective in pressure reduction as the same cast with a posteriorly placed heel, but they were more effective than the rocker heel. The height of the cast and configuration of the sole of the cast shoe had little effect on the observed patterns of force distribution. The wooden-soled post-operative shoe did decrease weight-bearing pressures as compared with barefoot walking and casts with a rocker heel but was less effective than the other devices studied. Peak loads measured at the sole of the foot were dependent on the position of the ankle and subtalar joints at the time of cast application.     

Morphological study of the transverse arch of the foot

The morphological study of the transverse arch was carried out using serial transverse sections of the foot. Ten specimens of intact feet, composed of bones from the Chopart joint to metatarsal heads, were examined. This part of the foot could be divided into six levels depending on the features of the transverse arch: 1. scaphoid-cuboid level, 2. midtarsal level, 3. cuneiform level, 4. proximal metatarsal level, 5. distal metatarsal level, and 6. sesamoid level. The shape of the articular surfaces and the trabecular arrangement of the midtarsal, metatarsal, and sesamoid bones were also studied.     

Foot pressures during gait: a comparison of techniques for reducing pressure points

PURPOSE: Various methods have been used to redistribute plantar surface foot pressure in patients with foot ulcers. This study was conducted to determine the effectiveness of four modalities (fracture walker, fracture walker with insert, and open and closed toe total contact casts) in reducing plantar foot pressure. METHODS: Ten healthy, normal volunteer subjects had an F-scan sensor (ultra thin shoe insert pressure monitor) placed under the right foot. They then ambulated on a flat surface, maintaining their normal gait. Dynamic plantar pressures were averaged over 10 steps at four different sites (plantar surface of great toe, first metatarsal head, base of fifth metatarsal, and plantar heel). All subjects repeated this sequence under five different testing conditions (barefoot, with a fracture walker, fracture walker with arch support insert, open and closed toe total contact cast). Each subject's barefoot pressures were then compared with the pressures during the different modalities. RESULTS: All four treatment modalities significantly reduced (p < 0.05) plantar pressure at the first metatarsal head (no method was superior). The fracture walker, fracture walker with insert, and open toe total contact cast significantly reduced pressure at the heel. Pressures at the base of the fifth metatarsal and great toe were not significantly reduced with any treatment form. CONCLUSION: The fracture walker, with and without arch support, and total contact cast can effectively reduce plantar pressure at the heel and first metatarsal head.     

拇外翻足并发第2跖骨头下疼痛的相关因素研究

目的:通过对拇外翻足足弓的X线指标与足底压力指标的检测,分析拇趾外翻角的变化与足弓X线测量指标变化及足底压力变化的相关性,探讨拇外翻足并发第2跖骨头下疼痛影响因素。方法:采用回顾性研究方法,观察自2012年1月至2013年6月治疗的254例(477足)拇外翻患者病历资料,记录患者第2跖骨头下疼痛及年龄的情况,把所有拇外翻足按并发第2跖骨头下疼痛的有无分为两组(疼痛组和无痛组),分别测量各组负重位拇外翻足拇趾外翻角(hallux abductor valgus angle,HAVA),第1、2跖骨间角(the inter-metatarsal angle between the first and second metatarsals,IMA1-2),第1、5跖骨间角(the inter-metatarsal angle between the first and fifth metatarsals,IMA1-5),内弓顶角、前弓顶角及第1、2跖骨头的相对长度,检测步态中第2跖骨头下峰压强、冲量、触地时间百分比等压力的情况。运用相关性分析及Logistic回归分析方法,探讨拇外翻足并发第2跖骨头下疼痛的影响因素。结果:Spearman相关性分析结果示HAVA分别与各测量指标的IMA1-2、IMA1-5、内弓顶角、前弓顶角、第2跖骨触地时间百分比呈相关性(P0.05,r=0.647、0.553、0.127、-0.165、0.158)。Logistic回归分析结果示并发第2跖骨头下疼痛的影响因素为HAVA、第2跖骨相对长度、第2跖骨头触地时间百分比(P0.05,ORj=1.030,1.069,1.060)。结论:拇外翻角的增大导致了拇外翻足足弓塌陷,使步态中第2跖骨头负重的时间延长,从而导致了第2跖头下疼痛的发生。