The Association Between Elevated Foot Skin Temperature and the Incidence of Diabetic Foot Ulcers: A Meta-Analysis

Exploring Thermal Dynamics in Wound Healing: The Impact of Temperature and Microenvironment

Exploring the critical role of thermal dynamics in wound healing, this manuscript navigates through the complex biological responses initiated upon wound infliction and how temperature variations influence the healing trajectory. Integrating biothermal physics, clinical medicine, and biomedical engineering, it highlights the significance of thermal management in wound care, emphasizing the wound microenvironment's division into internal and external domains and their collaborative impact on tissue repair. Innovations in real-time wound temperature monitoring, especially through intelligent wireless sensor dressings, are spotlighted as transformative, enabling precise wound condition management. The text underscores the necessity for further research to elucidate thermal regulation's molecular and cellular mechanisms on healing processes. It advocates for standardized protocols for localized heating treatments, integrating them into personalized wound care strategies to enhance therapeutic outcomes, improve patient well-being, and achieve cost-effective healthcare practices. This work presents a forward-looking perspective on refining wound management through sophisticated, evidence-based interventions, emphasizing the interplay between thermal dynamics and wound healing.

Telemedical Monitoring of Plantar Temperature in Diabetic Patients at Risk of Foot Ulcers

BACKGROUND

The worldwide prevalence of diabetic foot ulcers (DFUs) among persons with diabetes is estimated at 6.3%, with an annual incidence of 9.1 to 26.1 million persons. The early detection of asymmetrical plantar temperature elevation, followed by reduction of weight-bearing on the affected foot, may be an effective mode of prevention.

METHODS

Patients with diabetes and peripheral neuropathy (DFU risk groups 2/3) were monitored for plantar abnormalities with a telemedical system consisting of sole inserts with temperature sensors and photographic documentation. An open, prospective, randomized controlled trial was performed to determine whether this system prevented DFUs. The intervention and control groups were also trained in ulcer prevention and observed in follow-up at 6-month intervals for 24 months.

RESULTS

283 patients were recruited. In 85 137 observation days, DFUs arose in five patients in the control group (n = 143) and in no patient in the intervention group (n = 140). The primary outcome measure was the hazard ratio, which was calculated to be 0.015 (95% confidence interval [0; 19,717]; p = 0.25) after adjustment for age, sex, severity of neuropathy, and risk class. There were 239 alarms and 75 instructions to reduce weight-bearing on the foot. The subjects carried out the telemedical application on about 70% of the days of observation. Quality of life improved in both groups.

CONCLUSION

The tele-health system used in this trial is practical and enables the early detection of morbidity. Likely explanations for the unexpectedly low ulceration rate in this trial (and, in turn, for the lack of statistical significance) include the availability of a training program and regular follow-up examinations to patients in both arms of the trial, along with lower mobility levels due to the COVID pandemic.

The effectiveness of a thermography-driven preventive foot care protocol on the recurrence of diabetic foot ulcers in low-medical resource settings: An open-labeled randomized controlled trial

BACKGROUND

Plantar temperature monitoring, along with a comprehensive preventive foot care approach, is utilized to prevent recurrence of diabetic foot ulcers. However, there is a lack of standardized protocols for individuals with diabetic foot ulcer history in low-medical resource countries.

OBJECTIVE

This study investigated the efficacy of nurse-led, thermographic-evaluation-guided foot care in preventing diabetic foot ulcer recurrence in a low-medical resource country.

DESIGN

Single-blind, 1:1 allocation randomized controlled trial.

SETTINGS

Two wound care facilities with wound care nurse specialists in Indonesia.

PARTICIPANTS

120 patients with a diabetic foot ulcer history.

INTERVENTION

In the intervention group, baseline risk assessment including smartphone thermography evaluation was performed. Personalized foot care and education were conducted monthly for participants whose thermographs showed increased foot lesion temperature at baseline risk assessment. The control group received usual care and education using a booklet at baseline. The follow-up period was six months.

MAIN OUTCOME

Time to recurrence was evaluated using Kaplan-Meier survival analysis, and between-group comparisons were performed using the log-rank test. Potential risk factors were incorporated into the multivariate Cox regression model. Secondary outcomes included quality of life (European Quality of Life 5 Dimensions 3 Level Version) and foot care behavior, were analyzed using Mixed Models for Repeated Measures at baseline, third, and sixth follow-up (3 and 6 months from baseline).

RESULTS

120 participants (intervention 60, control 60) were randomized. The intervention group had a significantly lower recurrence rate than the control group (15% vs. 35%, p = 0.011) and a significant difference in time to ulceration (log-rank test, p = 0.009) after a 6-month follow-up period. Intervention care reduced the risk of diabetic foot ulcer recurrence by 59% (Hazard ratio 0.41, 95% confidence interval 0.18, 0.96, p = 0.039) in multivariate Cox regression analysis. On the third follow-up, total diabetic foot care behavior score (p < 0.001) was significantly improved by the intervention. On the sixth follow-up, mobility (p = 0.020), self-care (p = 0.023), pain/discomfort (p < 0.001), anxiety/depression (p = 0.016), EuroQol Visual Analogue Scale score (p = 0.002), and total diabetic foot care behavior score (p < 0.001) showed significant improvements in the intervention group.

CONCLUSIONS

Foot care and personalized education delivered at a frequency based on the risk level assessed by thermography effectively reduced diabetic foot ulcer recurrence, and improved quality of life and foot care behaviors.

REGISTRATION NUMBER

UMIN000039012.

TWEETABLE ABSTRACT

Nurse-led diabetic foot care and education reduced diabetic foot ulcer recurrence in Indonesia.

Reliability of the evidence to guide decision-making in foot ulcer prevention in diabetes: an overview of systematic reviews

Background

Reliable evidence on the effectiveness of interventions to prevent diabetes-related foot ulceration is essential to inform clinical practice. Well-conducted systematic reviews that synthesise evidence from all relevant trials offer the most robust evidence for decision-making. We conducted an overview to assess the comprehensiveness and utility of the available secondary evidence as a reliable source of robust estimates of effect with the aim of informing a cost-effective care pathway using an economic model. Here we report the details of the overview. [PROSPERO Database (CRD42016052324)].

Methods

Medline (Ovid), Embase (Ovid), Epistomonikos, Cochrane Database of Systematic Reviews (CDSR), Database of Abstracts of Reviews of Effectiveness (DARE), and the Health Technology Assessment Journals Library were searched to 17th May 2021, without restrictions, for systematic reviews of randomised controlled trials (RCTs) of preventive interventions in people with diabetes. The primary outcomes of interest were new primary or recurrent foot ulcers. Two reviewers independently extracted data and assessed the risk of bias in the included reviews.

Findings

The overview identified 30 systematic reviews of patient education, footwear and off-loading, complex and other interventions. Many are poorly reported and have fundamental methodological shortcomings associated with increased risk of bias. Most concerns relate to vague inclusion criteria (60%), weak search or selection strategies (70%) and quality appraisal methods (53%) and inexpert conduct and interpretation of quantitative and narrative evidence syntheses (57%). The 30 reviews have collectively assessed 26 largely poor-quality RCTs with substantial overlap.

Interpretation

The majority of these systematic reviews of the effectiveness of interventions to prevent diabetic foot ulceration are at high risk of bias and fail to provide reliable evidence for decision-making. Adherence to the core principles of conducting and reporting systematic reviews is needed to improve the reliability of the evidence generated to inform clinical practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01738-y.

Holistic multi-class classification & grading of diabetic foot ulcerations from plantar thermal images using deep learning

Purpose

Diabetic foot is a common complication associated with diabetes mellitus (DM) leading to ulcerations in the feet. Due to diabetic neuropathy, most patients have reduced sensitivity to pain. As a result, minor injuries go unnoticed and progress into ulcers. The timely detection of potential ulceration points and intervention is crucial in preventing amputation. Changes in plantar temperature are one of the early signs of ulceration. Previous studies have focused on either binary classification or grading of DM severity, but neglect the holistic consideration of the problem. Moreover, multi-class studies exhibit severe performance variations between different classes.

Methods

We propose a new convolutional neural network for discrimination between non-DM and five DM severity grades from plantar thermal images and compare its performance against pre-trained networks such as AlexNet and related works. We address the lack of data and imbalanced class distribution, prevalent in prior work, achieving well-balanced classification performance.

Results

Our proposed model achieved the best performance with a mean accuracy of 0.9827, mean sensitivity of 0.9684 and mean specificity of 0.9892 in combined diabetic foot detection and grading.

Conclusion

To the best of our knowledge, this study sets a new state-of-the-art in plantar foot thermogram detection and grading, while being the first to implement a holistic multi-class classification and grading solution. Reliable automatic thermogram grading is a first step towards the development of smart health devices for DM patients.

Development of a self-monitoring tool for diabetic foot prevention using smartphone-based thermography: Plantar thermal pattern changes and usability in the home environment

Thermography is a well-known risk-assessment tool for diabetic foot ulcers but is not widely used in the home setting due to the influence of the complicated home environment on thermographic images. This study investigated changes in thermographic images in complicated home environments to determine the feasibility of smartphone-based thermography in home settings. Healthy volunteers (age > 20 years) were recruited and required to take plantar thermal images using smartphone-based thermography attached to a selfie stick at different times of the day for 4 days. The thermal images and associated activities and environmental factors were then analyzed using content analysis. Areas with the highest temperature on the plantar thermal images were described and categorized. Device usability was evaluated using 10-point Likert scales, with 10 representing the highest satisfaction. A total of 140 plantar thermal images from 10 participants were analyzed. In 12 classifications, the three commonest patterns based on the highest temperature location were medial arch (42.1%), whole plantar (10.7%), and forefoot and medial arch (7.9%). The medial arch pattern is most frequently seen after awakening (67.5%) compared to other time points. Device usability was rated 7.5 out of 10 on average. This study was the first to investigate the plantar thermal patterns in the home settings, and the medial arch pattern was the most common hot area, which matches previous findings in well-controlled clinical settings. Therefore, smartphone-based thermography may be feasible as a self-assessment tool in the home setting.

Effect of thermometry on the prevention of diabetic foot ulcers: a systematic review with meta-analysis

OBJECTIVE

to analyze the effect of cutaneous foot thermometry in people with Diabetes Mellitus, compared with the standard prevention of foot ulcers adopted in these patients.

METHOD

a systematic review with meta-analysis. Protocol registered with PROSPERO (CRD42020202686). The recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were followed. The search was performed in the following data sources: SCOPUS, Web of Science, MEDLINE via PubMed, MEDLINE via EBSCO, MEDLINE via Biblioteca Virtual em Saúde, Embase, CINAHL, Cochrane Library, LILACS via Biblioteca Virtual em Saúde, Google Scholar, Biblioteca Digital Brasileira de Teses e Dissertações, Catálogo de Teses & Dissertações-Capes, Open Grey and ProQuest Dissertations and Theses. The risk of bias was assessed by the Cochrane Collaboration Risk of Bias Tool (RoB 2), the meta-analysis was performed in the Review Manager 5.4 software and the Certainty of evidence in the Grading of Recommendations Assessment, Development and Evaluation system.

RESULTS

of the 670 records, five articles were eligible. The meta-analysis was calculated for the prevention of the incidence of diabetic foot ulcers outcome, with effect summarization (RR 0.53; 95%CI 0.29-0.96; p=0.02), with certainty of moderate evidence.

CONCLUSION

thermometry showed a protective effect on the incidence of diabetic foot ulcers when compared to standard foot care.

Efecto de la termometría en la prevención de las úlceras del pie diabético: revisión sistemática con metaanálisis

Resumen Objetivo: analizar el efecto de la termometría cutánea del pie en personas con diabetes mellitus, en comparación con la prevención estándar de las úlceras del pie adoptada en estos pacientes. Método: revisión sistemática con metaanálisis. Protocolo registrado en PROSPERO (CRD42020202686). Se siguieron las recomendaciones de Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). La búsqueda se realizó en las fuentes de datos: SCOPUS, Web of Science, MEDLINE a través de PubMed, MEDLINE a través de EBSCO, MEDLINE a través de la Biblioteca Virtual en Salud, Embase, CINAHL, Cochrane Library, LILACS a través de la Biblioteca Virtual en Salud, Google Scholar, Biblioteca Digital Brasileña de Tesis y Disertaciones, Catálogo de Tesis y Disertaciones-Capes, Open Grey y ProQuest Dissertations and Theses. El riesgo de sesgo se evaluó mediante la Cochrane Collaboration Risk of Bias Tool (RoB 2), el metaanálisis se realizó con el software Review Manager 5.4 y la certeza de la evidencia se evaluó mediante el sistema Grading of Recommendations Assessment, Development and Evaluation. Resultados: de los 670 registros, cinco artículos fueron elegibles. El metaanálisis se calculó para el resultado prevención de la incidencia de úlceras del pie diabético, con sumarización del efecto (RR 0,53; IC95% 0,29, 0,96; p=0,02), con certeza de evidencia moderada. Conclusión: la termometría mostró un efecto protector sobre la incidencia de úlceras del pie diabético en comparación con el cuidado estándar del pie.

Effect of thermometry on the prevention of diabetic foot ulcers: a systematic review with meta-analysis*

Objective:

to analyze the effect of cutaneous foot thermometry in people with Diabetes Mellitus, compared with the standard prevention of foot ulcers adopted in these patients.

Method:

a systematic review with meta-analysis. Protocol registered with PROSPERO (CRD42020202686). The recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were followed. The search was performed in the following data sources: SCOPUS, Web of Science, MEDLINE via PubMed, MEDLINE via EBSCO, MEDLINE via Biblioteca Virtual em Saúde, Embase, CINAHL, Cochrane Library, LILACS via Biblioteca Virtual em Saúde, Google Scholar, Biblioteca Digital Brasileira de Teses e Dissertações, Catálogo de Teses & Dissertações-Capes, Open Grey and ProQuest Dissertations and Theses. The risk of bias was assessed by the Cochrane Collaboration Risk of Bias Tool (RoB 2), the meta-analysis was performed in the Review Manager 5.4 software and the Certainty of evidence in the Grading of Recommendations Assessment, Development and Evaluation system.

Results:

of the 670 records, five articles were eligible. The meta-analysis was calculated for the prevention of the incidence of diabetic foot ulcers outcome, with effect summarization (RR 0.53; 95%CI 0.29-0.96; p=0.02), with certainty of moderate evidence.

Conclusion:

thermometry showed a protective effect on the incidence of diabetic foot ulcers when compared to standard foot care.

Effectiveness of at-home skin temperature monitoring in reducing the incidence of foot ulcer recurrence in people with diabetes: a multicenter randomized controlled trial (DIATEMP)

INTRODUCTION

The skin of people with diabetic foot disease is thought to heat up from ambulatory activity before it breaks down into ulceration. This allows for early recognition of imminent ulcers. We assessed whether at-home monitoring of plantar foot skin temperature can help prevent ulcer recurrence in diabetes.

RESEARCH DESIGN AND METHODS

In this parallel-group outcome-assessor-blinded multicenter randomized controlled trial (7 hospitals, 4 podiatry practices), we randomly assigned people with diabetes, neuropathy, foot ulcer history (<4 years, n=295), or Charcot's neuro-arthropathy (n=9) to usual care (ie, podiatric treatment, education, and therapeutic footwear) or usual care plus measuring skin temperatures at 6-8 plantar sites per foot each day (enhanced therapy). If ∆T>2.2°C between corresponding sites on the left and right foot for two consecutive days, participants were instructed to reduce ambulatory activity until this hotspot disappeared and contact their podiatrist. Primary outcome was ulcer recurrence in 18 months on the plantar foot, interdigital, or medial/lateral/anterior forefoot surfaces; secondary outcome was ulcer recurrence at any foot site.

RESULTS

On the basis of intention-to-treat, 44 of 151 (29.1%) participants in enhanced therapy and 57 of 153 (37.3%) in usual care had ulcer recurrence at a primary outcome site (RR: 0.782 (95%CI 0.566 to 1.080), p=0.133). Of the 83 participants in enhanced therapy who measured a hotspot, the 24 subsequently reducing their ambulatory activity had significantly fewer ulcer recurrences (n=3) than those in usual care (RR: 0.336 (95% CI 0.114 to 0.986), p=0.017). Enhanced therapy was effective over usual care for ulcer recurrence at any foot site (RR: 0.760 (95% CI 0.579 to 0.997), p=0.046).

CONCLUSIONS

At-home foot temperature monitoring does not significantly reduce incidence of diabetic foot ulcer recurrence at or adjacent to measurement sites over usual care, unless participants reduce ambulatory activity when hotspots are found, or when aiming to prevent ulcers at any foot site.

TRIAL REGISTRATION NUMBER

NTR5403.

Meta-analyses of randomized controlled trials reporting the effect of home foot temperature monitoring, patient education or offloading footwear on the incidence of diabetes-related foot ulcers

AIM

The aim of this study was to perform an up-to-date systematic review and meta-analysis of randomized controlled trials (RCTs) examining the efficacy of home foot temperature monitoring, patient education and offloading footwear in reducing the incidence of diabetes-related foot ulcers.

METHODS

A literature search was performed using MEDLINE, PubMed, CINAHL, Scopus and Cochrane databases to identify relevant original studies. Meta-analyses were performed using intention-to-treat principals for worst (main analysis) and best (sub-analysis) case scenarios. Leave-one-out sensitivity analyses were used to assess the consistency of findings.

RESULTS

Of 7575 unique records, 17 RCTs involving 2729 participants were included. Four tested home foot temperature monitoring (n = 468), six examined patient education (n = 823) and seven assessed offloading footwear (n = 1438). Participants' who performed home foot temperature monitoring [odds ratio (OR) 0.51, 95% confidence interval (CI) 0.31 to 0.84; n = 468] and those provided offloading footwear (OR 0.48, 95% CI 0.29 to 0.80; n = 1438) were less likely to develop a diabetes-related foot ulcer. Patient education programmes did not significantly reduce diabetes-related foot ulcer incidence (OR 0.59, 95% CI 0.29 to 1.20; n = 823). Sensitivity analyses suggested that offloading footwear findings were consistent, but home foot temperature findings were dependent on the individual inclusion of one trial. All RCTs had either high or unclear risk of bias.

CONCLUSION

This meta-analysis suggests that offloading footwear is effective in reducing the incidence of diabetes-related foot ulcers. Home foot temperature monitoring also appears beneficial but larger trials are needed (PROSPERO registration no.: CRD42019135226).