Forefoot plantar shear stress distribution in hallux valgus patients

BackgroundHallux valgus is a common foot disorder often experienced with secondary callosities and metatarsalgia. Many factors including improper shoes might be responsible in the pathophysiology of the problem. Hallux valgus deformity has been shown to alter the biomechanics of the whole foot rather than affecting only the great toe. Due to changes in the biomechanical functioning of the first ray, other regions of the forefoot area have been shown to bear abnormal loads with increased vertical loading on medial, central and lateral forefoot regions. The purpose of this study was to investigate the pattern of forefoot plantar shear loading in hallux valgus patients and compare these results with those of control subjects.MethodsA total of 28 subjects were recruited for the study of which 14 were clinically diagnosed with hallux valgus. A custom built platform was used to collect peak pressure and shear data. A repeated measures analysis of variance was used to analyze the recorded data.FindingsAntero-posterior shear was significantly lower in the deformity group (p < 0.05). The lateral forefeet of the patients, however, experienced slightly higher shear loads (p > 0.05).InterpretationPropulsive shear force generation mechanism under the medial forefoot was impaired in the disorder group. In general, shear loading of the plantar feet shifted laterally. Previously hypothesized higher medio-lateral shear magnitudes under the hallux were not confirmed.     

足底主要韧带损伤对足纵弓应力分布的影响

目的 测量尸体足纵弓主要骨结构的应力分布,分析韧带损伤对其应力的影响.方法 7例正常成人新鲜尸体足标本,解剖显露足底跖筋膜、弹簧韧带、跖长韧带、跖短韧带,标记足纵弓主要骨结构.经电子万能试验机逐级加载至700 N,利用静态电阻应变测试仪和微型箔式电阻应变片,测量足底韧带损伤情况下足纵弓骨结构的表面应力,对结果进行统计学分析.结果 在足底韧带损伤前,最大应力值出现在跟骨,其次是第三跖骨、第二跖骨,均为压应力;而舟骨、腓骨、胫骨主要表现为拉应力.不同足底韧带损伤情况下骨结构表面应力差异有统计学意义(P＜0.05).结论 足底韧带损伤后,足纵弓骨结构的表面应力分布将发生改变.     

Lateral plantar nerve injury following steroid injection for plantar fasciitis

A 41 year old man presented with pain and numbness affecting the lateral aspect of his foot after a steroid injection for plantar fasciitis. Examination confirmed numbness and motor impairment of the lateral plantar nerve. The findings were confirmed by electromyographic studies. The anatomy of the lateral plantar nerve and correct technique for injection to treat plantar fasciitis are discussed.     

MRI of plantar fasciitis

At present, MRI is the only imaging method that can precisely visualize lesions of the superficial plantar aponeurosis, whether they be musculoaponeurositides, enthesopathies or tears, and whether they be acute or chronic, with or without complications. By its direct visualization of the lesion, MRI enables an accurate assessment of the injury to be made and thereby better orients the therapeutic strategy.     

Sonography of plantar fibromatosis

OBJECTIVE: Plantar fibromatosis is a rare benign fibroproliferative disorder of the plantar fascia that can be evaluated on sonography. Our study details the sonographic appearances of plantar fibromatosis. MATERIALS AND METHODS: We conducted a retrospective review of the clinical presentation, sonographic appearances, and clinical progress in 14 patients (range, 35-85 years; mean age, 53.1 years;) with plantar fibromatosis. Sonography was performed using either a 13-5-MHz multidimensional or 12.5-MHz linear array transducer. The location, sonographic appearances, and size of the plantar fibromatosis nodules were noted and correlated with symptom duration and clinical outcome. RESULTS: A total of 25 fibromatosis nodules in 19 feet were examined. On sonography, plantar fibromatosis was seen as a discrete fusiform nodular thickening of the plantar fascia, separate from the calcaneal insertion. Approximately one third (36%) of lesions were bilateral, and one quarter (26%) were multiple. All lesions were located either medially (60%) or centrally (40%) in the fascia. Most were hypoechoic (76%), were well defined (64%), and showed no acoustic enhancement (80%) or intrinsic vascularity (92%). No correlation was found between the echogenicity and size of plantar fibromatosis nodules or duration of symptoms (p < 0.01). One quarter of the affected feet had coexistent thickening of the plantar fascia at the calcaneal insertion with no related symptoms. CONCLUSION: Although the sonographic appearances of plantar fibromatosis vary, the appearances are characteristic enough to allow a specific diagnosis to be made. No clear relationship was found among the sonographic appearances, duration of symptoms, or clinical outcome.     

Reliability of plantar pressure platforms

Plantar pressure measurement is common practice in many research and clinical protocols. While the accuracy of some plantar pressure measuring devices and methods for ensuring consistency in data collection on plantar pressure measuring devices have been reported, the reliability of different devices when testing the same individuals is not known. This study calculated intra-mat, intra-manufacturer, and inter-manufacturer reliability of plantar pressure parameters as well as the number of plantar pressure trials needed to reach a stable estimate of the mean for an individual. Twenty-two healthy adults completed ten walking trials across each of two Novel emed-x^® and two Tekscan MatScan^® plantar pressure measuring devices in a single visit. Intraclass correlation (ICC) was used to describe the agreement between values measured by different devices. All intra-platform reliability correlations were greater than 0.70. All inter-emed-x^® reliability correlations were greater than 0.70. Inter-MatScan^® reliability correlations were greater than 0.70 in 31 and 52 of 56 parameters when looking at a 10-trial average and a 5-trial average, respectively. Inter-manufacturer reliability including all four devices was greater than 0.70 for 52 and 56 of 56 parameters when looking at a 10-trial average and a 5-trial average, respectively. All parameters reached a value within 90% of an unbiased estimate of the mean within five trials. Overall, reliability results are encouraging for investigators and clinicians who may have plantar pressure data sets that include data collected on different devices.     

Current treatment of plantar fasciitis

Plantar fasciitis is one of the most common complaints of chronic rearfoot heel pain seen by primary care providers. The etiology and differential diagnosis are numerous, as are treatment options. This article includes a definition of plantar fasciitis, anatomy, predisposing factors, physical examination techniques, differential diagnosis, and conservative nonsurgical treatment options. Plantar fasciitis may be acute, but is more often a chronic condition that is directly related to physical activity. The most common complaint is intense heel pain with the first step from bed in the morning and initial step after resting. This pain subsides with time, but returns in the evening after prolonged standing.     

The pathomechanics of plantar fasciitis

Plantar fasciitis is a musculoskeletal disorder primarily affecting the fascial enthesis. Although poorly understood, the development of plantar fasciitis is thought to have a mechanical origin. In particular, pes planus foot types and lower-limb biomechanics that result in a lowered medial longitudinal arch are thought to create excessive tensile strain within the fascia, producing microscopic tears and chronic inflammation. However, contrary to clinical doctrine, histological evidence does not support this concept, with inflammation rarely observed in chronic plantar fasciitis. Similarly, scientific support for the role of arch mechanics in the development of plantar fasciitis is equivocal, despite an abundance of anecdotal evidence indicating a causal link between arch function and heel pain. This may, in part, reflect the difficulty in measuring arch mechanics in vivo. However, it may also indicate that tensile failure is not a predominant feature in the pathomechanics of plantar fasciitis. Alternative mechanisms including 'stress-shielding', vascular and metabolic disturbances, the formation of free radicals, hyperthermia and genetic factors have also been linked to degenerative change in connective tissues. Further research is needed to ascertain the importance of such factors in the development of plantar fasciitis.     

足底筋膜的超声弹性图

目的通过超声弹性图对比不同年龄段正常人及足底筋膜炎病人的足底筋膜的硬度。材料与方法试验得到了医院研究伦理委员会的许可,并获得所有受试者的知情同意。研究使用彩色编码的超声弹性图对40名健康受试者及13例足底筋膜炎病人(筋膜炎组)的双脚进行检查。健康受     

Endurance of the ankle joint plantar flexor muscles in athletes with medial tibial stress syndrome: A case-control study

Medial tibial stress syndrome (MTSS) is a common overuse leg injury seen in athletes and can be recalcitrant to management. This cross-sectional study aimed to determine if there are differences in the isotonic endurance of the ankle joint plantar flexor muscles in athletes with MTSS compared to athletes without MTSS. The isotonic endurance of the ankle joint plantar flexors was measured in 30 participants diagnosed with MTSS, and 30 reference participants that were matched to MTSS participants on the basis of age (±5 years), gender, BMI (±5%) and type of sporting activity. The number of heel-rise repetitions of the participants in each group was compared for differences. There were no significant differences between participants with and without MTSS for age (p = 0.34), height (p = 0.40) or BMI (p = 0.27). The mean number of heel-rise repetitions performed by participants in the MTSS group was significantly less than the reference group (mean 23, S.D. 5.6, versus mean 33, S.D. 8.6; p < 0.001). These results suggest that athletes with MTSS have endurance deficits of the ankle joint plantar flexor muscles. Rehabilitation of athletes with MTSS should comprise training designed to enhance endurance of the lower limb musculature, including the ankle joint plantar flexors. It is not known whether a lack of endurance of the ankle joint plantar flexor muscles is the cause or effect of MTSS.     

Ultrasonographic appearance of the plantar fasciitis

PURPOSE: To study high frequency sonographic in the examination of plantar fasciitis (PF), which is a common cause of heel pain. MATERIALS AND METHODS: Our study was done with 25 PF (21 unilateral, 4 bilateral) and 15 control cases of similar age, weight and gender. In this study, the plantar fascial thickness (mainly), fascial echogenity and biconvexity were examined using 7.5 MHz linear phase array transducer. Perifascial fluid collection, fascial rupture and fascial calcification that are rarely seen were also examined. RESULTS: The fascial thickness ranges for the PF cases: for the symptomatic heels: 3.9-9.1 mm (mean: 4.75 +/- 1.52 mm), for the asymptomatic heels: 2.0-5.9 mm (mean: 3.37 +/- 1.0 mm) and for the control group: 2.1-4.7 mm (3.62 +/- 0.68 mm). The results were significantly different in Group I for symptomatic heels and the control group statistically for PF (P < .05). The echogenity of plantar fascia and biconvexity of plantar fascia were the major criteria for symptomatic heels. In three heels (10%), perifascial fluid was diagnosed, in three heels (10%) fascial calcification, in one heel (3%) partial fascial rupture. Subcalcaneal spur was encountered sonographically in both cases of Groups I and II. CONCLUSION: Ultrasonography (US) is the first step for PF, because of its easy and quick performance, availability and high sensitivity of diagnosis, low-cost and free radiation.     

Spontaneous rupture of the plantar fascia

In this study, rupture of the plantar fascia was seen in five feet, of which four had had plantar fasciitis. At the time of the injury, which is an acceleration type of motion, there is severe pain in the heel followed by the development of ecchymosis in the sole and toward the heel of the foot. With conservative symptomatic care, the acute symptoms as well as the plantar fasciitis symptoms subside, generally allowing full activity in 3 to 4 weeks.