Plantar pressure distribution in diverse stages of diabetic neuropathy

Human-in-the-loop optimization of rocker shoe to reduce plantar pressure and collision work simultaneously

BACKGROUND

Rocker shoes can be used to reduce foot pressure and adjust lower limb kinetics for various patient population, such as people with diabetic peripheral neuropathy. Selecting adequate properties of the rocker sole is of great importance for its efficacy. This study investigated the capability of human-in-the-loop optimization (HILO) to individually optimize apex position and angle of rocker shoe to reduce peak pressure and collision work simultaneously.

METHODS

Peak pressure, kinetic, and kinematic data were recorded from 10 healthy participants while walking at preferred speed wearing rocker shoes with adjustable apex position and angle. An evolutionary algorithm was used to find optimal apex parameters to reduce both peak pressure in medial forefoot and collision work. The optimized shoe (HILO shoe) was compared with generic optimal rocker settings (Chapman settings) and normal shoe.

FINDINGS

Compared to normal shoe, the HILO shoe had lower plantar pressure (pHILO = 0.007; pChapman = 0.044) and Chapman shoe showed higher collision work (pHILO = 0.025; pChapman = 0.014). Both HILO and Chapman shoe had smaller push-off work than normal shoe (pHILO = 0.001; pChapman < 0.001) with the Chapman shoe exhibited earlier push-off onset (pHILO = 0.257; pChapman = 0.016).

INTERPRETATION

The Human-in-the-loop optimization approach resulted in individualized apex settings which performed on average similar to Chapman settings but, were superior in selected cases. In these cases, medial forefoot could be further offloaded with apex angles larger than generic settings. The larger apex angle might increase the external ankle moment arm and push-off work. However, there is limited room for improvement on collision work compared to generic settings.

Pedobarographic evaluations in physical medicine and rehabilitation practice

The feet are complex structures that transmit loads transferred by other parts of the body to the ground and are involved in many static and dynamic activities, such as standing and walking. The contact area and pressure changes between the feet and the ground surface can be measured using pedobarographic devices. With pedobarographic examinations, it is possible to obtain a wide range of information needed to support clinical evaluation and diagnostic tests in physical medicine and rehabilitation practice. Foot structure and function, postural stability, lower extremity biomechanics, and gait analysis are among the areas that can be further investigated using pedobarography.

Impact of Race, gait speed and arch height on plantar loading

Diabetes is a leading cause for death in the United States, with African Americans (AA) being twice as likely to die from diabetes than White Americans (WA). AA are twice as likely to experience diabetes-related foot amputation due to foot ulcers, which are most often caused by high plantar pressure. While it is known that arch height, sex, family history of diabetes, Body Mass Index (BMI), age, and gait speed can impact plantar loading, there is a need to test the hypothesis that race in combination with the previously mentioned variables are significant predictors of plantar loading. To answer this question, plantar loading data was collected from 107 participants using an EMED pressure-measurement system (Novel Electronics, Inc, St Paul, MN, USA). Each participant walked barefoot at a self-selected walking pace ten times. Contact area, maximum force, and were force-time integral collected for each step on the pressure plate. A multiple linear regression was used to test if race, age, Arch Height Index (AHI), gait speed, sex assigned at birth, family history of diabetes, and BMI significantly predicted plantar loading. Race, age, AHI, gait speed, sex, and BMI were considered significant predictor variables for plantar loading. Most importantly, race was a significant predictor of maximum force in the hallux (β = 6.46, p < 0.001), rearfoot (β = -6.36, p < 0.001), and lateral midfoot (β = -2.72, p < 0.001), and the force-time integral in the hallux (β = 2.37, p < 0.001), rearfoot (β = -2.14, p < 0.001), and lateral midfoot (β = -0.65, p < 0.001). These findings could help with understanding why AA are more likely to develop diabetic foot ulcers than WA.

Diabetic Foot Considerations Related to Plantar Pressures and Shear

Diabetic foot ulcers are a complex, multifaceted, and widespread complication of diabetes mellitus. Although there are a multitude of risk factors contributing to diabetic foot ulcer development, pressure and (more recently) shear stresses are two biomechanical metrics that are gaining popularity for monitoring risk factors predisposing skin breakdown. Other areas of diabetic foot ulcers under research include plantar temperature measuring, as well as monitoring wear-time compliance and machine learning/AI algorithms. Charcot arthropathy is another diabetes complication that has a relationship with diabetic foot ulcer development, which should be monitored for development alongside ulcer development. The ability to monitor and prevent diabetic foot ulcer development and Charcot neuroarthropathy will lead to increased patient outcomes and patient quality of life.

Factors associated with changes in plantar pressure of people with peripheral diabetic neuropathy

Abstract

Diabetic neuropathy is one of the main complications of Diabetes Mellitus, which can lead to loss of protective sensation, motor, and plantar pressure alteration, generating deformities, abnormal gait and mechanical trauma to the feet.

Objective

to evaluate the distribution of plantar pressure, sensorimotor changes, balance and associated factors to plantar pressure changes in people with peripheral diabetic neuropathy.

Method

Cross-sectional study conducted with individuals registered in the primary public health service of a city in the east of São Paulo - Brazil. The sample was composed by people with Diabetes Mellitus and Peripheral Neuropathy identified by the Michigan Screening Instrument. It were investigated variables such as sensory-motor changes, static and dynamic plantar pressure using baropodometry and balance using the Berg scale. A significance level of 5% was adopted for all tests used.

Results

Of the 200 individuals evaluated, 52.55% had no plantar protective sensitivity, the static evaluation did not demonstrated changes in the peak of plantar pressure, however in the dynamics the mean in the right foot was 6.0 (±2) kgf/cm2 and 6,7 (±1.62) kgf/cm2 on the left foot, the center of static pressure on the right foot was lower (10.55 ± 3.82) than on the left foot (11.97 ± 3.90), pointing hyper plantar pressure. The risk of falling was high, ranging from 8 to 56 points, with an average of 40.9 (±10.77).

Conclusion

The absence of protective plantar sensitivity, increased pressure, biomechanical changes lead to loss of balance and are predictive of complications in the feet due to diabetic neuropathy.

Effects of contoured insoles with different materials on plantar pressure offloading in diabetic elderly during gait

To investigate the effect of contoured insoles constructed of different insole materials, including Nora Lunalastik EVA, Nora Lunalight A fresh, Pe-Lite, and PORON Medical 4708 with Langer Biomechanics longitudinal PPT arch pads on offloading plantar pressure on the foot of the elderly with Type 1 or 2 diabetes during gait. Twenty-two elderly with Type 1 or 2 diabetes participated in the study. Their plantar pressure was measured by using an insole measurement system, while the participants walked 10 m in their bare feet or used each experimental insole in random order. The plantar surface was divided into four specific regions including the toes, forefoot, midfoot, and rearfoot. The mean peak pressure (MPP) and pressure-time integral (PTI) of ten steps with or without wearing one of the four insoles were analyzed on the dominant foot and the four specific plantar regions. After completion of the activities, the participants scored each insole from 1 (the least comfortable) to 10 (the most comfortable). The analysis of variance (ANOVA) factor of the insoles had significant effects on the MPP (P < 0.001) and PTI (P = 0.004) in the dominant foot during gait. Pairwise comparison results showed that the MPP and PTI in the dominant foot were significantly lower (P < 0.001) with PORON Medical 4708 than barefoot, Nora Lunalight A fresh, and Pe-Lite. Additionally, the insole materials had a significant effect for the forefoot (P < 0.001) and rearfoot (P < 0.001) in terms of the MPP and PTI compared with the barefoot condition during gait. Regardless of the plantar region, the MPP and PTI values were the lowest when PORON Medical 4708 was used as the insole material among four insole materials. Meanwhile, a significantly lower MPP and PTI can be found in the forefoot and rearfoot with the use of the four experimental insoles when compared with barefoot. The soft insole materials (i.e., PORON medical 4708 and Nora Lunalastik EVA) had a better performance than the rigid insole materials (i.e., Nora Lunalight A fresh, and Pe-Lite) on plantar pressure offloading for diabetic elderly.

Diabetic Foot scientific activities in Endocrinology and Metabolism Research Institute

Introduction

Diabetic Foot (DF) as a common complication of Diabetes should be intensive intervention for prevention, management and rehabilitation. In this regard, Diabetes Research Center of Endocrinology and Metabolism Research Institute (EMRI) of Tehran University of Medical Sciences (TUMS) considered DF as a priority research area to investigate multidimensional aspects of DF care. We are intended to summarize DF research studies affiliated to the EMRI for over the last two decades.

Methods

Three Electronic databases including Web of Science, PubMed, and Scopus were searched until January 2020 to find articles about DF published affiliated to EMRI. The main concepts of search strategies were "diabetes", "Foot". 115 documents retrieved from these databases which screened for inclusion and exclusion criteria. The visualization of the network of co-authorship of authors and co-occurrence of keywords was illustrated and documents were analyzed for content according to the Main areas of DF Research studies.

Result

64 related documents including original articles, reviews, letters, notes, and book chapter have included to this study. According to the objectives of the retrieved studies, DF documents and research studies categorized in the two main groups including DF prevention, classification and risk stratification in addition management of DF.

Conclusion

Despite conducted research and educational activities in DF prevention and management, the following topics would be considered as well: effective offloading treatment, correcting the nutritional status for improving wound healing and novel educational strategies for diabetic foot multi-disciplinary team.

Effect of tap dance on plantar pressure, postural stability and lower body function in older patients at risk of diabetic foot: a randomized controlled trial

INTRODUCTION

To examine the effects of tap dance (TD) on dynamic plantar pressure, static postural stability, ankle range of motion (ROM), and lower extremity functional strength in patients at risk of diabetic foot (DF).

RESEARCH DESIGN AND METHODS

A randomised, single-blinded, two-arm prospective study of 40 patients at risk of DF was conducted. The intervention group (n=20) received 16 weeks of TD training (60 min/session×3 sessions/week). The control group attended four educational workshops (1 hour/session×1 session/month). Plantar pressure, represented by the primary outcomes of peak pressure (PP) and pressure-time integral (PTI) over 10 areas on each foot, was measured using the Footscan platform system. Secondary outcomes comprised static postural stability, ankle ROM and lower extremity functional strength.

RESULTS

Reductions in intervention group PP (right foot: mean differences=4.50~27.1, decrease%=25.6~72.0; left foot: mean differences=-5.90~6.33, decrease%=-22.6~53.2) and PTI at 10 areas of each foot (right foot: mean differences=1.00~12.5, decrease%=10.4~63.6; left foot: mean differences=0.590~25.3, decrease%=21.9~72.6) were observed. Substantial PP and PTI differences were noted at the second through fourth metatarsals, medial heel and lateral heel in the right foot. Substantial PP and PTI differences were detected at metatarsals 1 and 2 and metatarsal 2 in the left foot, respectively. Moderate training effects were found in plantar flexion ROM of both feet, lower extremity functional strength, and length of center-of-pressure trajectory with eyes closed and open (r=0.321-0.376, p<0.05).

CONCLUSIONS

A 16-week TD training program can significantly improve ankle ROM, lower extremity functional strength, and static postural stability. To attain greater improvements in plantar pressure, a longer training period is necessary.

TRIAL REGISTRATION NUMBER

ChiCTR1800014714.

A Novel Low-Cost Wireless Footwear System for Monitoring Diabetic Foot Patients

Diabetic foot is one of the main complications of diabetes with the characteristics of high incidence and difficulty in treatment. Diabetic patients with peripheral neuropathy may develop foot ulcers, and in severe cases amputations are required and some may even die. Plantar pressure can be used to assess the risk of developing diabetic foot, but the existing plantar pressure monitoring methods are not suitable for long-term monitoring in daily life. This study presents a novel low-cost shoe system for daily monitoring of plantar pressure in diabetics. It includes an insole with pressure sensor array, which can dynamically monitor the plantar pressure and display the changes of plantar pressure in real time in the mobile phone to provide early warning for patients with high risk of diabetic foot. As for the sensor, copper and carbon black were adopted as the electrode and conductive filler respectively, enabling a mass production with low price. It was soft and bendable, meeting the performance needs of daily plantar pressure monitoring. All devices were encapsulated in shoes, and the data was transmitted wirelessly through Bluetooth, which did not affect the user's walking. After using random forest for feature selection, five classifiers were used to classify the plantar pressure of healthy people, diabetic patients without peripheral neuropathy, and diabetic patients with peripheral neuropathy collected by this system. The experimental results showed that the accuracy of the random forest classifier was the highest, reaching 94.7%, which indicated that the system could be useful for daily plantar pressure monitoring of diabetic patients.