正常足与外翻足前足承重比例与跖骨头下压力的研究

目的从生物力学角度探讨外翻足前足承重比例及跖骨头下压力的改变情况.方法将测试对象分为正常组(160足)、轻中度外翻组(100足)、重度外翻组(56足)三组,运用我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.结果轻中度外翻足前足承重比例较正常足增加,重度外翻足前足承重比例介于正常足与轻中度外翻足之间.外翻足存在着前足压力外移的趋势,这种改变和畸形的程度相关.结论从生物力学角度证明,外翻前足承重比例及各跖骨头下压力的变化随外翻畸形程度增加出现不同程度的变化.     

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。     

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。     

正常足与外翻足的足底压力研究

目的　对正常足与外翻足的足底压力进行测量。方法　运用自行研制的足底生物力学测试系统对30 名健康人60 足,45 例外翻患者89 足进行了行走时足底压力的测试。结果　重度外翻组31 足和正常组相比,第一跖骨头下压力明显减低( P< 0.001),第二跖骨头下压力明显增加(P< 0 .05),第三、五跖骨头下压力有增高的趋势。结论　正常人前足第一跖骨头下压力最高,并向外侧递减。重度外翻足前足第一跖骨头下压力明显减低,第二跖骨头下压力明显增高     

正常足与拇外翻足的足底压力研究

目的 对正常足与拇外翻足的足底压力进行测量。方法 运用自行研制的足底生物力学测试系统对３０名健康人６０足,４５例拇外翻患者８９足进行了行走时足底压力的测试。结果 重度拇外翻组３１足和正常组相比,第一跖骨头下压力明显减低,第二跖骨头下明显增另,第三,五跖骨头下压力有增高的趋势。结论正常人前足第一跖骨关下压力最高,并向外侧递减,重度拇外翻足前足第一跖骨头下压力明显减低,第二跖骨头下压力明显增高。     

外翻合并第二跖骨头下疼痛的生物力学定量研究

目的探讨跖骨头下压力变化与(足,母)外翻合并跖骨头下疼痛的关系,并对引起第二跖骨头下疼痛的跖骨头下压力进行定量分析.方法采用由中国中医研究院骨伤科研究所生物力学实验室研制的足底压力测试系统,对58名正常人(116足),32例(45足)(足,母)外翻单纯合并第二跖骨头下疼痛患者,56例(102足)(足,母)外翻无足底疼痛患者进行足底压力测试,将三组跖骨头下压力进行比较.采用病例-对照设计,研究压力与疼痛的关系,并对引起第二跖骨头下疼痛的压力进行定量分析.结果 (1)(足,母)外翻单纯合并第二跖骨头下疼痛组分别与(足,母)外翻无足底疼痛组及正常组比较,第二跖骨头下压力均明显增高(均P＜0.05);(2)第二跖骨头下压力高于正常组与第二跖骨头下压力不高于正常组比较,疼痛的发生率明显增加(P＜0.05,OR＞3,OR 95%CI＞1);(3)(足,母)外翻合并第二跖骨头下疼痛组第二跖骨头下压力占体重的5.20%～7.29%.结论跖骨头下压力异常增高是跖骨头下疼痛的危险因素,第二跖骨头下压力超过体重的5.20%,极易出现跖骨头下疼痛.     

(足,母)外翻合并第二跖骨头下疼痛的生物力学定量研究

目的探讨跖骨头下压力变化与蹰外翻合并跖骨头下疼痛的关系，并对引起第二跖骨头下疼痛的跖骨头下压力进行定量分析。方法采用由中国中医研究院骨伤科研究所生物力学实验室研制的足底压力测试系统，对58名正常人（116足），32例（45足）拇外翻单纯合并第二跖骨头下疼痛患者，56例（102足）拇外翻无足底疼痛患者进行足底压力测试，将三组跖骨头下压力进行比较。采用病例一对照设计，研究压力与疼痛的关系，并对引起第二跖骨头下疼痛的压力进行定量分析。结果（1）蹲外翻单纯合并第二跖骨头下疼痛组分别与拇外翻无足底疼痛组及正常组比较，第二跖骨头下压力均明显增高（均P〈0．05）；（2）第二跖骨头下压力高于正常组与第二跖骨头下压力不高于正常组比较，疼痛的发生率明显增加（P〈0．05，OR〉3，OR95％CI〉1）；（3）拇外翻合并第二跖骨头下疼痛组第二跖骨头下压力占体重的5．20％-7．29％。结论跖骨头下压力异常增高是跖骨头下疼痛的危险因素，第二跖骨头下压力超过体重的5．20％，极易出现跖骨头下疼痛。     

放射学分析(足母)外翻伴发外侧跖骨痛的原因

(足母)外翻是前足部常见疾病,好发于女性,常常伴发外侧,特别是2、3跖骨痛.研究表明,(足母)外翻足在负重状态下足底压力外移[1],外侧足底压力增高[2-3],导致外侧跖骨头下产生疼痛.另外,相对较长的外侧跖骨也是产生跖骨痛的原因之一.然而,作者在临床中常常发现一些患者为双侧(足母)外翻畸形,而只有一侧伴发外侧跖骨痛.就作者所知,目前还没有对产生这种差别的原因进行研究的相关报道.作者认为如果将双侧(足母)外翻伴发与不伴发跖骨痛的左右足进行对比研究,能消除个体间的差异,可以更客观地了解(足母)外翻足伴发跖骨痛的原因.     

第1跖趾关节融合术后前足评分与足底压力的分析

[目的]分析第1跖趾关节融合术后对前足功能影响,以及对推进期足底压力的影响.[方法]15例患者共18足,行第1跖趾关节融合术后2年以上,根据AOFAS评分系统,对第1跖趾关节功能评分,并与正常对照组进行足底压力测试.测量前足底推进期的(足母)趾下、第1～5跖骨下共6处的峰值压强、峰值压力、压强-时间积、压力-时间积四个参数.[结果]融合术后AOFAS第1跖趾关节评分满意,术后组的(足母)趾下四项参数均明显小于正常人组.与时间相关的参数在(足母)趾下,以及第2、4、5跖骨头下小于正常人组,并具有明显差异.第1跖骨头下的峰值压强与峰值压力与对照组没有统计学差异.[结论]第1跖趾关节融合术后患者在推进期,前足跖骨头的足底压力分布与正常人基本相同.术后前足功能改善.术后(足母)趾下压力减少,但是对前足压力分布没有影响.     

[足母]外翻的术后并发症分析

[足母]外翻是女性患者多见的一种足部畸形,主要表现为[足母]趾外翻、第一跖骨内翻及第一跖骨头内侧的[足母]囊炎,常伴发疼痛性胼胝、锤状趾及骨关节炎等。[足母]外翻实际上包含两部分概念：a）第一趾骨相对于第一跖骨的外翻畸形．b）第一跖骨相对于足纵轴线的内翻畸形。     

Comparison between the plantar pressure effects of toe separators and insoles in patients with hallux valgus at a one-month follow-up

BackgroundVarious designs of foot orthoses for hallux valgus have been developed to reduce foot pain. The plantar pressure assessment can determine the better intervention. This study aimed to compare the effectiveness of plantar pressure distribution in patients with hallux valgus during walking with toe separator and insole.MethodPatients with hallux valgus were randomized into one of two interventions: prefabricated toe separator or customized insole. The plantar pressure distribution of the participants was measured during walking with the devices after use for one month with an in-shoe measurement system.ResultsTwenty-three participants were analyzed. After 1-month, significant peak pressures and pressure-time integral reductions were observed during walking in the middle forefoot (64.28 kPa and 28.97 kPa s, respectively) and lateral forefoot regions (54.03 kPa and 22.30 kPa s, respectively) after insole use compared with a toe separator.ConclusionsAfter one month of use, the customized insole was more effective in plantar pressure reduction than the toe separator for a hallux deformity.     

Forces under the hallux valgus foot before and after surgery.

Abnormalities in the hallux valgus foot and changes after surgery were investigated by measuring the distribuiion of load on the foot in walking. Hallux valgus was associated with reduced load imposed on the toes, and on the medial side of the forefoot, compared with a large sample of healthy feet. Abnormalities correlated with the degree of the deformity. Both Keller's operation and a wedge displacement osteotomy of the first metatarsal not only failed to restore normal loading but increased the abnormalities of loading seen preoperatively. A large decrease in the angle between first and second metatarsals as a result of surgery minimized this increase. A silastic arthroplasty did not carry high loads when used to treat hallux valgus, but near normal loads were imposed on it when used for hallux rigidus. Considerable variability was found in the loading distribution on the healthy feet. The distribution between first and second metatarsal heads was partially dependent upon their protrusions, relative to the direction of walking. The changes in the relationships between the loadings on the forefoot and skeletal shape in response to surgical operations are important for our understanding of treatment of the hallux valgus foot.     

Effects of the Lapidus Arthrodesis and Chevron Bunionectomy on Plantar Forefoot Pressures

Hallux valgus with or without first ray insufficiency has been strongly implicated as a contributing factor in lesser metatarsal overload. The principle goals of a bunionectomy are to relieve the pain, correct the deformity, and restore first metatarsophalangeal joint congruity. Until now, little evidence has been available to assess the effects of bunionectomy procedures on forefoot pressure. The primary aim of the present prospective study was to evaluate the preoperative and postoperative plantar pressures after 2 specific bunionectomies: the chevron bunionectomy and Lapidus arthrodesis. A total of 68 subjects, 34 in each group, were included for radiographic and pedographic evaluation. Both procedures demonstrated radiographic improvements in the mean intermetatarsal and hallux abductus angles. The mean hallux plantar pressure decreased significantly in both procedure groups (p < .001). However, Lapidus group exhibited an increase in the mean fifth metatarsal head plantar pressure (p = .008) and pressure under the fifth metatarsal as a percentage of the total forefoot pressure (p = .01). Furthermore, the pressure under the second metatarsal as a percentage of the total forefoot pressure decreased significantly (p = .01). This study suggests that the Lapidus arthrodesis and chevron bunionectomy both provide correction for hallux valgus deformity, but when comparing forefoot load sharing pressures, the Lapidus arthrodesis appeared to have greater influence on the load sharing distribution of forefoot pressure than did the bunionectomy employing the chevron osteotomy.     

Preliminary results of a plantar plate for Lapidus arthrodesis

The TMT I arthrodesis is an established procedure for the correction of hallux valgus deformity associated with the instability of the TMT-I joint. A risk of transfer metatarsalgia is reported in the literature associated with persistant elevation of MT-I. Detailed information for ideal positioning of the arthrodesis is missing so far. Clinical, radiological and padobarografical results and their correlations were analyzed with special consideration of the elevation position of the MT-I in a TMT-I arthrodesis using the plantar plate osteosynthesis. Postoperative changes in plantar pressure and force distribution occured after TMT-I arthrodesis. A postoperative increase of the load under the medial forefoot and the dependence on the positioning of MT-I in the sagittal plane has been shown. The authors suggest, that increased load of the medial forefoot and constant pressures and forces under the central forefoot may lead to a relative relief of the area, which might explain the postoperative reduction of metatarsalgia.     

The biomechanics of the first metatarsal bone in hallux valgus: A preliminary study utilizing a weight bearing extremity CT

BackgroundHallux valgus is a common but aetiologically not perfectly understood condition. Imaging in hallux valgus is based on weight bearing plain radiographs or in exceptional cases on non-weight bearing computerized tomography (CT)-studies.MethodsA portable extremity CT was used to study the forefoot with focus on first metatarsal bone in ten hallux valgus patients and five asymptomatic controls at rest and at weight bearing. Two-dimensional (2D) or three-dimensional (3D) hallux valgus angles, intermetatarsal angles and various other parameters were measured on CT data and the measurements between study groups were compared. The measured angles were also compared to angles measured on plain radiographs.Results2D or 3D angles from CT data sets can be used to evaluate hallux valgus. In hallux valgus, when compared with normal asymptomatic foot, the first metatarsal bone is medially deviated (intermetatarsal angle is wider), the width of the forefoot is increased and the proximal phalanx pronates. Between the study groups there was a statistically significant difference of the measured 3D hallux valgus angles at weight bearing but not at rest suggesting the importance of weight bearing CT studies when evaluating hallux valgus.ConclusionsTo our knowledge, this is the first time weight bearing CT data is presented when evaluating hallux valgus, offering a true alternative to plain radiographs. The relationships of bones of the forefoot, including rotational changes, can be reliably measured using this imaging method.     

Plantar pressure distribution and pain after distal osteotomy for hallux valgus: A prospective study of 22 patients with 12-month follow-up

BackgroundElevated pressure under the central forefoot region is common in hallux valgus and this is often associated with metatarsalgia.ObjectiveTo ascertain whether there was a difference in pain and plantar pressure distribution parameters after correction of the deformity by two distal metatarsal osteotomy techniques.MethodsTwenty-two patients randomly assigned to distal chevron or Lindgren first metatarsal osteotomy were evaluated prospectively with dynamic plantar pressure measurement, quality of life scores and clinical and radiographic measurements. Data were collected pre-operatively, at 6 and 12 months after surgery. Results of the combined operated group were compared with an age-matched control group.ResultsThere were no significant differences in plantar pressure distribution parameters between the two operated groups at any occasion. At 6 months peak pressure was significantly less under the lateral forefoot in the operated feet compared with the non-operated feet and significantly greater under the central forefoot than in the control group and the medial forefoot than under the non-operated feet, although the operated group had normalised after 12 months. The visual analogue scale (VAS) showed significant improvements after both surgical techniques.ConclusionBoth surgical techniques resulted in significant clinical and radiographic improvements and reduced the level of pain, although the foot pressure recordings demonstrated no biomechanical effect.     

Plantar pressure distribution in normal,hallux valgus and hallux limitus feet

Selected dynamic plantar pressure measurements of 30 control, 30 hallux valgus and 30 hallux limitus subjects, using an EMED-SF system and a two-step method of data collection, were analysed for significant differences, with a one-way analysis of variance being performed with P<0.05. In comparison to normal control subjects, those with hallux valgus feet demonstrated significant medial plantar peak and mean pressures under the first, second and third metatarsal heads. In contrast, hallux limitus feet showed significantly high mean pressure under the hallux, lesser toes, third and fourth metatarsal heads, indicating a more lateral forefoot load.