Foot Pressure Distribution Research Articles

Surgical Treatment of Calcaneal Deformity in a Select Group of Patients with Myelomeningocele

The surgical treatment of calcaneal deformity in patients with myelomeningocele has not been uniformly successful in correcting the deformity and preventing recurrence. The purpose of the present study was to examine the results of posterior transfer of the anterior tibial tendon with concurrent procedures in an attempt to balance the muscular forces on the foot and ankle and to obtain a plantigrade foot. We investigated whether surgery improved pressure distribution over the plantar surface of the foot and whether concurrent abnormal movements observed at the knee, hip, and pelvis influenced the surgical outcome. Thirty-one feet in eighteen patients who were able to walk were included in the study. The mean age at the time of surgery was seven years and four months, and the mean duration of follow-up was forty-seven months. Eight patients were classified as having an L5-level myelomeningocele, and ten patients were classified as having a sacral level myelomeningocele. A tibialis anterior tendon transfer was performed in all patients, and accompanying osseous deformities were also corrected in twelve feet. Measurements on plain radiographs, the results of gait analyses, and dynamic foot pressures that were determined before surgery and at the time of the final follow-up were compared. No recurrence or worsening of the deformity was observed in any of the patients, and no other types of foot deformity developed after surgery. Postoperative kinematic studies showed a significant (p < 0.0001) increase in peak plantar flexion and a significant decrease in peak dorsiflexion force of the ankle in the stance phase of gait. Peak pressures under the forefoot and midfoot were increased after surgery, and the relative amount of weight-bearing on the heel as compared with the forefoot was shifted toward more equal weight-bearing. However, less improvement in foot-pressure distribution was observed in patients with increased pelvic rotation before surgery. Those patients also had decreased knee extension in stance phase and increased hip abduction and pelvic obliquity both before and after surgery in comparison with patients who had normal pelvic rotation. Appropriately combined corrective surgical procedures for the treatment of calcaneal deformity in patients with myelomeningocele can effectively reduce the pressure placed on the calcaneus, increase pressures in the forefoot and midfoot, and prevent recurrence of the calcaneal deformity. However, in the presence of excessive pelvic movement in the coronal and transverse planes and decreased knee extension in stance phase, adequate improvement in pressure distribution over the plantar surface of the foot is not likely to occur after this type of foot surgery. Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Changes in Dynamic Foot Pressure After Surgical Treatment of Valgus Deformity of the Hindfoot in Cerebral Palsy

Calcaneal lengthening osteotomy and extra-articular arthrodesis of the subtalar joint are two methods used for the correction of valgus deformity of the heel and forefoot abduction. The purpose of this study was to compare the operative results of these procedures in patients with cerebral palsy who were able to walk. We focused primarily on changes in radiographic parameters and how altered mobility of the subtalar joint by the two operative methods would modify pressure distribution over the plantar surface of the foot. A total of eighty-one feet in forty-seven patients were included in the study. The mean age at the time of surgery was eight years and one month, and the mean follow-up period was thirty-nine months. The subjects were divided into two groups; Group I consisted of thirty-seven feet in twenty-two patients who underwent a calcaneal lengthening osteotomy, and Group II comprised forty-four feet in twenty-five patients who underwent an extra-articular subtalar arthrodesis. Preoperative and final follow-up radiographs and dynamic pedobarographs were used to evaluate the results. The feet in both groups were found to be similarly deformed before surgery, by radiographic measurements and dynamic foot-pressure analysis. Both operative procedures led to improved radiographic indices; however, calcaneal pitch failed to improve after the subtalar arthrodesis. After surgery, the relative vertical impulse was decreased for the hallux, first metatarsal head, and medial aspect of the midfoot in both groups, while it was increased for the lateral aspect of the midfoot and calcaneus. On the other hand, postoperatively, the relative vertical impulse of the medial aspect of the midfoot was higher and the relative vertical impulse of the first through fourth metatarsal heads was lower in the group that had subtalar arthrodesis compared with the group that had a calcaneal lengthening osteotomy and the normal control subjects. Extra-articular subtalar arthrodesis appears to be an effective means to achieve predictable correction of severe valgus deformity of the heel in patients with cerebral palsy who are able to walk; however, supination deformity of the forefoot remains and calcaneal equinus is not corrected. On the other hand, we believe that the calcaneal lengthening osteotomy is the treatment of choice because postoperative foot-pressure distribution more closely approximates the normal foot-pressure distribution.

보행시 족저압 분포와 척추 측만의 상관관계 연구

보행시 족저압 분포와 척추 측만의 상관관계 연구

Custom Therapeutic Insoles Based on Both Foot Shape and Plantar Pressure Measurement Provide Enhanced Pressure Relief

The purpose of this study was to determine whether custom insoles tailored to contours of the barefoot pressure distribution and shape of a patient's foot can reduce plantar pressures in the metatarsal head (MTH) region to a greater extent than conventional custom insoles. Seventy regions of elevated barefoot pressures (mean peak 834 kPa under MTHs) were identified in 20 subjects with diabetes. Foam box impressions of their feet were sent to three different orthotic supply companies for fabrication of custom insoles. One company was also given plantar pressure data, which were incorporated into the insole design. Measurements of in-shoe plantar pressures were recorded during gait for the three custom insoles in a flexible and a rocker-bottom shoe. Peak pressure and force-time integral were extracted for analysis. In 64 of 70 regions, the shape-plus-pressure-based insole in the flexible shoe achieved superior unloading compared with the two shape-based insoles. On average, peak pressure was reduced by 32 and 21% (both P <or= 0.0001) and force-time integral by 40 and 34% (both P < 0.0001) compared with the shape-based insoles. At the midfoot, force-time integral was increased by 51 and 33% (both P < 0.01). Similar trends were found using the rocker-bottom shoe. Compared with insoles based only on shape, the use of foot shape with barefoot plantar pressure measurements in designing custom insoles results in enhanced offloading of high-pressure areas under the forefoot. This offloading was achieved by a greater transfer of load to the midfoot without additional loading of other forefoot structures.

등산화의 종류와 보행동작에 따른 지면반력 및 족저압력 분석

등산화의 종류와 보행동작에 따른 지면반력 및 족저압력 분석

Are in-shoe pressure characteristics in symptomatic idiopathic pes cavus related to the location of foot pain?

People who have extremely high arched feet may be subject to substantial levels of foot pain, despite the lack of obvious pathology. This study sought to investigate the effect of pes cavus on pain intensity and location and on the magnitude and distribution of foot pressure. Measurements were derived from the more symptomatic foot of 130 participants with painful, idiopathic pes cavus. Data were collected using Pedar ® in-shoe pressure sensors and averaged over nine randomly selected steps. Participant information, including location and intensity of pain, Foot Posture Index values and anthropometric and “quality of life” variables, were also recorded. Painful idiopathic pes cavus seems to provoke a more cautious gait pattern than normal, with reduced peak and mean pressure values, particularly in the fore- and rear-foot regions. In particular, participants with pain confined to the rear-foot exhibit an antalgic gait pattern, with lower pressure values and a longer period of foot-ground contact in the heel region than those with pain only in the fore-foot. We determined no clear predictors of pain in terms of foot posture or demographics, although people with high body mass index values are more likely to have pain in several regions. The relationship between the posture of the foot and the presentation of pain remains unclear, however we believe that the presence of heel pain in pes cavus may be more restricting than fore-foot pain.

Foot pressure distribution during walking in young and old adults

BackgroundMeasurement of foot pressure distribution (FPD) is clinically useful for evaluation of foot and gait pathologies. The effects of healthy aging on FPD during walking are not well known. This study evaluated FPD during normal walking in healthy young and elderly subjects.MethodsWe studied 9 young (30 ± 5.2 years), and 6 elderly subjects (68.7 ± 4.8 years). FPD was measured during normal walking speed using shoe insoles with 99 capacitive sensors. Measured parameters included gait phase characteristics, mean and maximum pressure and force, and relative load.Time-series measurements of each variable for all sensors were grouped into 9 anatomical masks.ResultsElderly subjects had lower normalized maximum pressure for the medial and lateral calcaneal masks, and for all medial masks combined. In the medial calcaneus mask, the elderly group also had a lower absolute maximum and lower mean and normalized mean pressures and forces, compared to young subjects. Elderly subjects had lower maximum force and normalized maximum force and lower mean force and normalized mean forces in the medial masks as well.ConclusionFPD differences between the young and elderly groups were confined to the calcaneus and hallux regions and to the medial side of the foot. In elderly subjects, weight bearing on the lateral side of the foot during heel touch and toe-off phases may affect stability during walking.

Radiographic measurements and plantar pressure distribution in normal, hallux valgus and hallux limitus feet

This study investigated the relationship between static osseous radiographic foot measurements and mean peak pressure recordings of 10 selected regions of the foot in 30 normal subjects and in 30 subjects with hallux valgus or hallux limitus. The results suggest that dynamic peak pressure distribution beneath the foot is unrelated to those static weight-bearing radiographic parameters tested, in normal subjects and those with hallux valgus or hallux limitus. Other intrinsic or extrinsic biomechanical or physiological factors, which may have an influence on foot function, must be responsible for variation of pressure distribution within the foot.

The average pressure distribution of the diabetic foot: Can it be used as a clinical diagnostic aid?

INTRODUCTION:: The aim of this study was to investigate whether averaged data obtained from pressure distribution measurements could be used to distinguish differences between diabetic feet with normal and no sensation. The calculated parameters most sensitive to any differences were established, and the potential of the averaged maximum pressure picture as a quick recognition pattern of a neuropathic diabetic foot was assessed for clinical use. METHODS:: Dynamic pressure distribution data was collected from 56 diabetics using an emed SF2 platform. The first step method was used, and only one step per subject was recorded for this set of data. Each subject completed a questionnaire which included a grading of the sensitivity to vibration on the plantar surface of the foot evaluated by a clinician. The subjects were subsequently divided into four groups depending on this sensitivity, but only data from the two groups with normal (n=16) and no sensation (n=12) were evaluated in this study. Control data were obtained from two separate sources: for adults (n=40) using an emed SF4 platform and for teenagers (n=73) using a mini-emed platform. The groupmask evaluation program from the novel-win software and the average program from the novel-ortho software were used to evaluate the data. Each dynamic pressure distribution was automatically masked using the foot recognition algorithms of the 'novel' mask, which divided the foot into ten areas: the heel, midfoot, first, second, third, fourth and fifth metatarsal heads (MTH), hallux, second toe, and remaining toes. The parameters analysed for each of these masks included: the mean peak pressure, maximum force, contact time, beginning of contact time, pressure-time integral and force-time integral. RESULTS AND DISCUSSION:: The results showed clearly that both pressure and contact time are important parameters in differentiating a neuropathic from a non-neuropathic diabetic foot. Values of the maximum force in each area of the foot showed no difference between the two groups. Owing to the small sample sizes for the two diabetic groups the 95% confidence limits were relatively large, however, clear differences existed between the two sets of data for the mean peak pressure and the mean pressure-time integral for the total foot and the forefoot. Based upon this data, peak pressure values above 56 N/cm(2) for the 1st MTH, 46 N/cm(2) for the 3rd MTH, 35 N/cm(2) for the 4th MTH and 26 N/cm(2) for the 5th MTH, and pressure-time integrals above 31 Ns/cm(2) for the 1st MTH, 21 Ns/cm(2) for the 2nd MTH, 24 Ns/cm(2) for the 3rd MTH, 19 Ns/cm(2) for the 4th MTH and 12 Ns/cm(2) for the 5th MTH would suggest the possibility of a neuropathic diabetic foot. The averaged maximum pressure distribution picture for each group showed some differences between diabetic feet with normal sensation and those with no sensation. However, owing to the small size of the groups, it was felt that the averaged pressure pictures were, at the moment, limited in their use as a quick recognition pattern for the clinician. Although further data has already been collected and will be added to the databank in the near future. CONCLUSIONS:: These data show that averaged maximum pressure pictures alone do not provide sufficient information to differentiate clearly between a non-neuropathic and a neuropathic diabetic foot. Parameters obtained from the dynamic process, in particular, the pressure-time integral, must also be taken into account. It is anticipated that this work will be continued in order to investigate differences between other dynamic processes of potential importance, such as the location and speed of the gait line. ACKNOWLEDGEMENTS:: The authors would like to thank Dr M Morlock and Dr T Tsvetkova for the control data.

Quantification and comparison of influences on the abnormal pressure distribution in neuropathic diabetic feet produced by individually fitted shoe constructions

Quantification and comparison of influences on the abnormal pressure distribution in neuropathic diabetic feet produced by individually fitted shoe constructions

Field Dependence and Body Balance

This study reports four points about the portable Rod and Frame Test performance of 30 Japanese women in terms of body balance. The primary findings using a stabilometer are: (a) field dependence correlated negatively with increased sway path within 1 min. both while a dot pattern as a visual stimulus was stationary and while it was moving. (b) Field dependence correlated positively with the difference in sway path between the two following phases, in one of which the subjects watched the horizontal visual movement to the right and in the other movement to the left. (c) Motion aftereffect had no direct and immediate influence on sway path, but rather a latent and long-term effect. And on a pedograph which measures the distribution of foot pressure and the shape of the sole, (d) field dependence correlated negatively with anterior positions of the center of foot pressure and with the proportion of the front part to the rear of the sole. Over-all, field dependence measured by the Rod and Frame Test seems to be associated with body posture when dot patterns are viewed.

Wearable unrestraining footprint analysis system. Applications to human gait study

The paper describes an original wearable plantar dynamics analysis system, which puts subjects under particularly unrestraining walking conditions. It is based on foot-pressure distribution measurement in soft, thin, but reliable multisensor soles composed of 2×127 barosensitive cells. The system was applied to gait and posture studies of ten nonpathologic subjects. Specific computing and graphic programs were developed for gait analysis and clinical applications. Online visualisation of footprints allowed the operator to monitor the experiments. Because of human gait variability, data were collected over a prolonged sequence, and a ‘mean step’ was statistically computed, which is more representative of individual walking. Initial graphic and numerical results confirm the value of the method and offer encouragement for further studies intended to define normal or pathologic gait patterns. The system included additional signal inputs for correlative studies with kinematic or physiological parameters.