Plantar Pressure Plate Research Articles

Walking with individualized 3D-printed minimal footwear increases foot strength and produces subtle changes in unroll pattern

IntroductionThis 5-month follow-up study, involving 66 subjects (38 intervention, 28 control; 34 females, 32 males), evaluated the biomechanics of walking while wearing bespoke, 3D-printed footwear.MethodsA 3D scanner was used to obtain foot shape, which was subsequently modified to yield a suitable instep and additional room in the forefoot and toe areas, to allow for potential shape changes of the foot. Shoes were manufactured using TPU laser sintering. Pre (T0) and post (T1) the intervention, plantar pressures were collected using a plantar pressure plate (3 trials per foot) and toe flexor strength (5 trials per foot) was measured using a dynamometer, for control and intervention groups. Plantar pressure peak patterns and center-of-pressure (CoP) timing was analysed using 2D and 1D Statistical Parametric Mapping, respectively. Toe strength changes were expressed in percent and per individual as: 100 x ((strength@T1strength@T0) / strength@T0).ResultsPeak pressure distribution did not differ between control and intervention populations, or between T0 and T1. Center-of-pressure unroll differed between barefoot and shod conditions at T0 for the intervention group. When barefoot, the intervention group at T1 showed a more lateral CoP in early stance and a more anterior CoP in late stance compared to T0. In the intervention group, toe strength increased significantly by 48.5% between T0 and T1.DiscussionOverall, the results indicate that the bespoke, 3D-printed footwear did not significantly affect peak pressure distribution compared to barefoot walking. However, center-of-pressure patterns during gait were influenced, particularly in the intervention group, with analysis indicative of barefoot subjects' CoP moving faster in early and mid-stance than when shod. Additionally, the intervention led to a significant increase in toe strength. These findings contribute to our understanding of the biomechanical effects of customized 3D-printed footwear and highlight the potential benefits of such interventions in improving foot function and strength.

Effect of loading history on material properties of human heel pad: an in-vivo pilot investigation during gait

BackgroundThis study was aimed to develop a novel dynamic measurement technique for testing the material properties and investigating the effect of continuous compression load on the structural and mechanical properties of human heel pad during actual gait.MethodsThe dual fluoroscopic imaging system (DFIS) and dynamic foot-ground contact pressure-test plate were used for measuring the material properties, including primary thickness, peak strain, peak stress, elastic modulus, viscous modulus and energy dissipation rate (EDR), both at time zero and following continuous loading. Ten healthy pilot subjects, aged from 23 to 72 (average: 46.5 ± 17.6), were enrolled. A “three-step gait cycle” is performed for all subjects, with the second step striking at a marked position on the force plate with the heel to maintain the location of the tested foot to be in the view of fluoroscopes. The subjects were measured at both relaxed (time-zero group) and fatigue (continuous-loading group) statuses, and the left and right heels were measured using the identical procedures.ResultsThe peak strain, peak stress, elastic modulus, and EDR are similar before and after continuous load, while the viscous modulus was significantly decreased (median: 43.9 vs. 20.37 kPa•s; p < 0.001) as well as primary thicknesses (median: 15.99 vs. 15.72 mm; p < 0.001). Age is demonstrated to be moderately correlated with the primary thicknesses both at time zero (R = -0.507) and following continuous load (R = -0.607). The peak stress was significantly correlated with the elastic modulus before (R = 0.741) and after continuous load (R = 0.802). The peak strain was correlated with the elastic modulus before (R = -0.765) and after continuous load (R = -0.801). The correlations between the viscous modulus and peak stress/ peak strain are similar to above(R = 0.643, 0.577, − 0.586 and − 0.717 respectively). The viscous modulus is positively correlated with the elastic modulus before (R = 0.821) and after continuous load (R = 0.784).ConclusionsBy using dynamic fluoroscopy combined with the plantar pressure plate, the in vivo viscoelastic properties and other data of the heel pad in the actual gait can be obtained. Age was negatively correlated with the primary thickness of heel pad and peak strain, and was positively correlated with viscous modulus. Repetitive loading could decrease the primary thickness of heel pad and viscous modulus.

Understanding Foot Loading and Balance Behavior of Children with Motor Sensory Processing Disorder.

Sensory processing disorder (SPD) could influence the neuromuscular response and adjustment to external sensory discrimination and lead to disruptions in daily locomotion. The objective of the current study was to compare plantar loadings and foot balance during walking, running and turning activities in SPD children in order to reveal the behavioral strategy of movement and balance control. Six SPD children and six age-match healthy controls participated in the test using a FootScan plantar pressure plate. The time-varying parameters of forces, center of pressure and foot balance index were analyzed using an open-source one-dimensional Statistical Parametric Mapping (SPM1d) package. No difference was found in foot balance and plantar loadings during walking, while limited supination–pronation motion was observed in the SPD children during running and turning. The plantar forces were mainly located in the midfoot region while less toe activity was found as well. Findings should be noted that SPD children had limited supination–pronation movement for shock attenuation in the foot complex and reduced ankle pronation to assist push-off and toe gripping movements. Understanding the behavior of plantar loading strategy and balance control during walking, running and turning activities may provide clinical implications for the rehabilitation and training of daily tasks.

Reliability and Repeatability of the Footwork Plantar Pressure Plate System.

Plantar pressure plate instruments are commonly used in clinical practice and biomechanical analysis and are useful to establish a relationship between gait disorders and foot pressure. The aim of this study was to verify the reliability and repeatability of the Footwork pressure plate system for static and dynamic conditions. Forty healthy adults, without apparent gait pathology, were recruited. For the static condition, participants were asked to stand static on the Footwork pressure plate for 5 sec in natural position (arms on either side of the body, feet shoulder-width apart in a comfortable angle, and looking ahead). For the dynamic condition, subjects were told to step five times with each foot on the plate following the three-step protocol. Both conditions were performed in two testing sessions spaced by 1 week. Intrasession and intersession reliability for both conditions showed substantial to almost perfect intraclass correlation coefficient (ICC) values, and low coefficient of variation, low standard error measure, and low percentage error. Intrasession ICCs were 0.724 to 0.993 for static condition evaluation and 0.639 to 0.986 for dynamic condition evaluation. Intersession reliability ICCs ranged from 0.850 to 0.987 for the static condition and from 0.781 to 0.996 for the dynamic condition. Coefficient of variation values were below 8% in both cases and percentage error calculated from standard error measure were less than 10%. The present work demonstrates that the Footwork plantar pressure plate system is a reliable instrument for collecting plantar pressures in static and dynamic conditions. Reliability data were higher for the static trials, probably because of the individual physiologic fluctuations, which are larger during dynamic gait. Reliability for intersession and average intrasession trials were higher than single-test reliability. The results from the present work can be used as a starting point for future research and to establish a basis for sample sizes for investigations that would use the Footwork platform.

Locally linear embedding and plantar pressure–time graph selection in heel pain classification: An observational, case-control study

Plantar heel pain mainly manifests during the gait cycle when the whole foot is in contact with the floor, which corresponds to the second rocker of the gait. This moment can be studied through the analysis of pressure–time graphs obtained using plantar pressure plate systems. However, these graphs are complex, and a dimensionality reduction method, such as locally linear embedding (LLE), greatly assists in their comprehension. This observational, case-control pilot study included 45 subjects divided into case (n = 21) and control (n = 24) groups, depending on the presence/absence of plantar heel pain. The second rocker pressure–time graphs of the 45 subjects were obtained using the Footwork Pro® plantar pressure plate system. These graphs were analyzed and defined as the dynamic simultaneity surfaces (DSSs). This complex structure was composed of four dimensions: the dynamic simultaneity time (DST), slope upward grade (α), slope downward grade (β), and height (h), and were reduced into one dimension and classified into pathological and non-pathological subjects using the LLE method. All 45 DSSs were successfully reduced and classified to distinguish between the case (plantar heel pain) and control (non-plantar heel pain) subjects. This study is the first to use the LLE method for gait analysis. This method serves as a novel and promising tool for the study and classification of pathological and non-pathological gait cycles. This method opens the door for future research and analysis, with significant potential to assess diagnosis, treatment follow-up, and injury prevention in physical medicine consultations.

Children with Obesity Experience Different Age-Related Changes in Plantar Pressure Distributions: A Follow-Up Study in China.

Age is a key factor in plantar pressure distributions during the development of obese children. However, the existing evidence for age-related plantar pressures of obese children is not sufficient to make clear how the plantar pressures would change with the increasing age. This study aimed to evaluate the plantar pressure redistributions of obese children after a three-year follow-up and to further compare these changes with normal-weighted children. Ten obese children and eleven normal-weighted counterparts were involved in this study. Plantar pressure measurements were undertaken using a Footscan® plantar pressure plate on two test sessions three years apart. Peak pressure, pressure-time integral, standard maximum force, and z-scores of these variables were analyzed. Loading transference analyses were applied to detect the different loading transferring mechanisms between obese and normal-weighted children. Significantly increased plantar pressures were observed at the lateral forefoot and midfoot for obese children, which gradually deviated from those of normal-weighted children over the 3 years. With the increasing age, obese children displayed a lateral loading shift at the forefoot in contrast to the normal-weighted. Early interventions are cautiously recommended for obese children before the plantar loading deviation gets worse as they grow older.

The Influence of the Improvement of Calf Strength on Barefoot Loading

The purpose of this study was to determine whether enhancement of calf muscular strength can produce influence on plantar pressure in barefoot running. Ten healthy male subjects (age:22±2.5 years, height: 1.76±0.4m, body mass: 65±2.5kg) participate this experiment enduring 8-week strength training adopting by calf raise movement on calf muscle. A medical ultrasonic instrument (Q6, China) was used to observe the variation of calf muscular morphology. A plantar pressure plate ( Novel Emed, Germany) was used to collect the variation of 8-region plantar pressure. After 8-week strength training, a significant increasing trend between pre-and post-strength training in subject`s pinnation angle (PA) of the gastrocnemius was found. Under strength training, there are some significant variations between pre-and post-plantar pressure. The start point of center of pressure (COP) gradually forward (middle foot 80%, forefoot 20%); the peak pressure of subject`s heel foot (HF) significantly lower; the maximal force in second-third metatarsal (M 2-3), medial foot (MF) and HF significantly decrease; the contact area in other toe (OT) significantly increase as well as MF and HF significantly decrease; the time-force integral in M2-3 and HF significantly lower and in MF significantly enhance. These results suggest, the enhancement of calf muscular strength may produce positively influence on beginning transitional process from shod running to barefoot running and is also worth to as a feasible way to recommend. However, the effects of strength straining on plantar pressure do not fully explore and still need to deeply explore own to existing limitations.

P 093 - Comparison of three bipedal tasks to quantify contribution of proprioception to postural stability in healhty children and adolescents

Static postural sway can be quantified as variation in body’s center of force (COF) position across time using a plantar pressure plate. We aimed to compare capability of three clinically feasible bipedal tasks to extract the contribution of proprioception to postural stability. We measured the postural sway of 24 healthy volunteers (age range 10.2–17.6 years) with a plantar-pressure plate with three different standing tasks: (1) normal standing, (2) normal standing on soft foam, and (3) feet together standing. Each task was repeated eyes closed to emphasize the contribution of proprioception on maintaining the postural stability. The effect of closing the eyes varied among the tasks, and was greatest in the feet together standing task, possibly due to greater proprioceptive demands in the more difficult tasks. It appears that standing feet together is a potential task for quantifying contribution of proprioception to postural stability.

Effects of different movement modes on plantar pressure distribution patterns in obese and non-obese Chinese children

Walking, slow running (jogging) and fast running often occur in daily life, Physical Education Class and Physical Fitness Test for children. However, potential impact of jogging and running on plantar pressure of children is not clear. The purpose of this study was to compare the characteristics of plantar pressure distribution patterns in obese and non-obese children during walking, jogging and running, and evaluate biomechanical effects of three movements on obese children. A 2-m footscan plantar pressure plate (RSscan International, Belgium) was used to collect the gait data of 20 obese children (10.69±2.11years; 1.51±0.11m; 65.15±14.22kg) and 20 non-obese children (11.02±1.01years; 1.48±0.07m; 38.57±6.09kg) during three movements. Paired t-test and independent sample t-test were performed for statistical comparisons and ANOVA was used for comparisons of gait characteristics among three movements. Significance was defined as p <0.05. Propulsion phase during jogging for obese children was the longest among three movements (p=0.02). Peak pressures under metatarsal heads IV, V (M4, M5), midfoot (MF), heel medial (HM) and heel lateral (HL) during jogging for obese children were the highest among three movements (p=0.005, p=0.003, p=0.004, p=0.03, p=0.01). Arch index (AI) of left foot during jogging for obese children was the largest (p=0.04). ConclusionsPlantar pressure distribution during three movements changed differently between two groups. The peak pressures under most plantar regions and AI during jogging for obese children were the largest among three movements, indicating that jogging caused more stress to their lower extremities. Obese children perhaps should not consider jogging as regular exercise.

Plantar Pressure Detection with Fiber Bragg Gratings Sensing System.

In this paper, a novel fiber-optic sensing system based on fiber Bragg gratings (FBGs) to measure foot plantar pressure is proposed. This study first explores the Pedar-X insole foot pressure types of the adult-size chart and then defines six measurement areas to effectively identify four foot types: neutral foot, cavus foot, supinated foot and flat foot. The plantar pressure signals are detected by only six FBGs, which are embedded in silicone rubber. The performance of the fiber optic sensing is examined and compared with a digital pressure plate of i-Step P1000 with 1024 barometric sensors. In the experiment, there are 11 participants with different foot types to participate in the test. The Pearson correlation coefficient, which is determined from the measured results of the homemade fiber-optic plantar pressure system and i-Step P1000 plantar pressure plate, reaches up to 0.671 (p < 0.01). According to the measured results from the plantar pressure data, the proposed fiber optic sensing system can successfully identify the four different foot types. Measurements of this study have demonstrated the feasibility of the proposed system so that it can be an alternative for plantar pressure detection systems.

Prediction of walking speed using single stance force or pressure measurements in healthy subjects

Walking speed is one of the best measures of overall walking capacity. In plantar pressure measurements, walking speed can be assessed using contact time, but it is only moderately correlated with walking speed. The center of pressure might be of more value to indicate walking speed since walking speed alters foot loading. Therefore, the purpose of this study is to assess walking speed using the velocity of the center of pressure (VCOP).Thirty-three subjects walked over a Footscan pressure plate at three speed conditions; slow, preferred, and fast. Walking speed was measured by a motion analysis system. (Multiple) linear regression analysis was used to indicate the relation between walking speed and independent variables derived from the pressure plate such as mean VCOP and stance time for all walking conditions separately and together.The mean VCOP had the highest correlation coefficient value with walking speed for all walking conditions combined (0.94) and for the preferred walking condition (0.80). The multiple regression analysis, based on a number of additional parameters, revealed a small to modest increase in the performance of predicting walking speed (r=0.98 for combined and r=0.93 for preferred).The mean VCOP was the best predictor for walking speed when using a plantar pressure plate. The mean VCOP predicts the walking speed with a 95% accuracy of 0.20m/s when healthy subjects walk at their preferred walking speed.

The effect of posture on the osseous relations in the foot.

Discrepancies observed between clinical findings and a weightbearing foot X-ray might be caused by a patients' positioning. This study's main objective was to determine the effect of a subjects' posture on the osseous relations of the foot. Anatomical markers were placed on the skin of the foot of 17 subjects. A plantar pressure plate assessed the percentage weight on the foot and weight distribution over the foot. Medial longitudinal foot angles were derived from the markers and compared between the 10 postures. The effect of percentage weight and weight distribution on the foot angles was determined by multiple regression analysis. The foot angles were significantly affected by the postures. The multiple regression analysis revealed the weight on the foot and the mediolateral weight distribution over the foot as important factors for the foot angles. A subjects posture significantly influences the osseous relations in the foot.

Relationship between Running Speed and Initial Foot Contact Patterns

This study assessed initial foot contact patterns (IFCP) in a large group of distance runners and the effect of speed on the IFCP. We determined the strike index to classify the runners in IFCP groups, at four speeds (3.2, 4.1, 5.1, and 6.2 m·s), by measuring center of pressure (COP) with a 2-m plantar pressure plate. Such a system allows a direct localization of the COP on the plantar footprint and has a low threshold value (2.7 N·cm), resulting in more accurate COP data at low ground reaction forces than when obtained from force plate. The IFCP distribution evolves from mostly initial rearfoot contact (IRFC) (82%) at 3.2 m·s to more anterior foot contacts with an approximately equal distribution of IRFC (46%) and initial midfoot or forefoot contact (54%) at 6.2 m·s. Approximately 44% of the IRFC runners showed atypical COP patterns with a fast anterior displacement of the COP along the lateral shoe margin. Apart from the different COP patterns, these atypical IRFC were also characterized by a significantly higher instantaneous vertical loading rate than the typical IRFC patterns. The IFCP distribution changes were due to intraindividual alterations in IFCP at higher speeds. That is, 45% of the runners made one or even two "transitions" toward a more anterior IFCP (and 3% shows some other type of transition between initial foot contact styles as speed increases). However, 52% of the runners remained with the same IFCP.

Development of an Adjustable Sinus Tarsi Device for Flatfoot Correction: A Pilot Study in a Sawbones Model1

Development of an Adjustable Sinus Tarsi Device for Flatfoot Correction: A Pilot Study in a Sawbones Model1

Can RSScan footscan® D3D™ software predict injury in a military population following plantar pressure assessment? A prospective cohort study

BackgroundInjury in initial military training is common with incidences from 25 to 65% of recruits sustaining musculoskeletal injury. Risk factors for injury include extrinsic factors such as rapid onset of high volume training, but intrinsic factors such as lower limb biomechanics and foot type. Prediction of injury would allow more effective training delivery, reduce manpower wastage and improve duty of care to individuals by addressing potential interventions. Plantar pressure interpretation of footfall has been shown to reflect biomechanical intrinsic abnormality although no quantifiable method of risk stratification exists. ObjectiveTo identify if pressure plate assessment of walking gait is predictive of injury in a military population. Method200 male subjects commencing Naval Officer training were assessed by plantar pressure plate recording, of foot contact pressures. A software interpretation, D3D™, stratified the interpretation to measure 4 specific areas of potential correction. Participants were graded as to high, medium and low risk of injury and subsequently followed up for injury through their basic training. ResultsSeventy two percent of all injuries were attributed to subjects in the high and medium risk of injury as defined by the risk categorization. 47% of all injuries were sustained in the high-risk group. Participants categorized in the high-risk group for injury were significantly more likely to sustain injury than in medium or low groups (p<0.001, OR 5.28 with 95% CI 2.88, 9.70). ConclusionsPlantar pressure assessment of risk for overuse lower limb injury can be predictive of sustaining an overuse injury in a controlled training environment.

Effects of obesity on dynamic plantar pressure distribution in Chinese prepubescent children during walking

The purpose of this study was to examine the effects of obesity on dynamic plantar pressure distribution during walking for prepubescent children. A footscan® plantar pressure plate system was used to collect the gait data. Fifty obese prepubescent children and fifty non-obese prepubescent children walked across the plate at preferred speed while barefoot. SPSS11.5 was used for analysis and significance is defined as p<0.05. Obese subjects had longer midstance duration (p=0.004) and shorter propulsion duration (p=0.047) compared to non-obese subjects. The peak pressures under the metatarsal heads II–V, midfoot and heel lateral (p=0.004, p=0.03, p=0.004) were significantly higher for obese subjects. The time to peak pressures under the toes II–V, the metatarsal heads IV, V and midfoot (p=0.008, p=0.009, p=0.01, p=0.006), and pressure rate under the heel medial and lateral heel (p=0.03, p=0.009) were also significantly higher. In addition, the arch index for the left foot (p=0.01), the left and right foot axis angle (p=0.027, p=0.03) were significant larger among obese subjects. We also found that obese subjects had significantly higher relative regional impulses of contact with the plate at the midfoot of left foot (p=0.01) and the forefoot of right foot (p=0.047). There were also differences in foot balance during the midstance and propulsion phase (p=0.0004, p=0.03) and in pronation extent during midstance and propulsion phases between left and right foot in the obese group (p=0.03, p=0.01). In conclusion, the obese children have weaker walking stability with flatter foot pattern, the larger foot axis angle and dynamic plantar pressure distribution changes compared to non-obese children.