Preventative Sensor-Based Remote Monitoring of the Diabetic Foot in Clinical Practice

Diabetes and its complications, particularly diabetic foot ulcers (DFUs), pose significant challenges to healthcare systems worldwide. DFUs result in severe consequences such as amputation, increased mortality rates, reduced mobility, and substantial healthcare costs. The majority of DFUs are preventable and treatable through early detection. Sensor-based remote patient monitoring (RPM) has been proposed as a possible solution to overcome limitations, and enhance the effectiveness, of existing foot care best practices. However, there are limited frameworks available on how to approach and act on data collected through sensor-based RPM in DFU prevention. This perspective article offers insights from deploying sensor-based RPM through digital DFU prevention regimens. We summarize the data domains and technical architecture that characterize existing commercially available solutions. We then highlight key elements for effective RPM integration based on these new data domains, including appropriate patient selection and the need for detailed clinical assessments to contextualize sensor data. Guidance on establishing escalation pathways for remotely monitored at-risk patients and the importance of predictive system management is provided. DFU prevention RPM should be integrated into a comprehensive disease management strategy to mitigate foot health concerns, reduce activity-associated risks, and thereby seek to be synergistic with other components of diabetes disease management. This integrated approach has the potential to enhance disease management in diabetes, positively impacting foot health and the healthspan of patients living with diabetes.

Fast-Track Pathway: An Effective Way to Boost Diabetic Foot Care

Diabetes is a chronic disease that challenges global health issues in many aspects. Diabetic foot ulcer (DFU) is one of the most common causes of reduced quality of life and increased hospitalization, amputation, treatment costs, and mortality in patients. Improper patients' knowledge, unsatisfactory education and training of healthcare workers, and limited facilities are the major cause of delayed referral and downscale management in DFUs. The diabetic foot clinical pathway is pivotal in providing best practices based on the latest standards and patient preferences. In the diabetic foot clinical pathway provided by the Iran Ministry of Health, the common concepts and grading systems are well defined for diabetic foot specialists so that patients can be diagnosed correctly and referred properly. Based on clinical examination guidelines, patients with diabetes are classified into low-risk, moderate-risk, high-risk, and active diabetic foot ulcer groups. One of this Pathway's main objectives is to prevent the patient from getting the first ulcer, prevent frequent recurrence ulcers, and most importantly, prevent minor and major amputation.

Smart Offloading Boot System for Remote Patient Monitoring: Toward Adherence Reinforcement and Proper Physical Activity Prescription for Diabetic Foot Ulcer Patients

BACKGROUND

A critical factor in healing diabetic foot ulcers is patient adherence to offloading devices. We tested a smart offloading boot (SmartBoot) combined with a smartwatch app and cloud dashboard to remotely monitor patient adherence and activity. In addition, the impact of SmartBoot on balance, gait, and user experience was investigated.

METHODS

Fourteen volunteers (31.6±8.7 years; 64% female) performed natural activities (eg, sitting, standing, walking) with and without the SmartBoot for approximately 30 minutes. All participants completed balance tests, 10-meter walking tests at slow, normal, and fast pace while wearing the SmartBoot, and a user experience questionnaire. The accuracy of real-time adherence reporting was assessed by comparing the SmartBoot and staff observation. Center of mass (COM) sway and step counts were measured using a validated wearable system.

RESULTS

Average sensitivity, specificity, and accuracy for adherence and non-adherence were 90.6%, 88.0%, and 89.3%, respectively. The COM sway area was significantly smaller with the SmartBoot than without the SmartBoot regardless of test condition. Step count error was 4.4% for slow waking, 36.2% for normal walking, 16.0% for fast walking. Most participants agreed that the SmartBoot is easy to use, relatively comfortable, nonintrusive, and innovative.

CONCLUSIONS

To our knowledge, this is the first smart offloading system that enables remote patient monitoring and real-time adherence and activity reporting. The SmartBoot enhanced balance performance, likely due to somatosensory feedback. Questionnaire results highlight SmartBoot's technical and clinical potential. Future studies warrant clinical validation of real-time non-adherence alerting to improve wound healing outcomes in people with diabetic foot ulcers.

Characteristics of new patient referrals to specialised diabetic foot units across Europe and factors influencing delays

OBJECTIVE

Foot ulcers are a common complication of diabetes and are associated with an increase in lower limb amputation and death. Early referral to a specialised unit is recommended. The aim of this study was to assess the characteristics of new-patient referrals to specialised diabetes foot care units across Europe and to determine the factors involved in delayed referral.

METHOD

In this prospective observational study, consecutive patients with a new foot ulcer presenting to nine diabetic foot centres in five European countries (France, Germany, Italy, Spain and the UK) were included.

RESULTS

Some 25% of the 332 patients included had presented with a foot ulcer >3 months before referral to the participating foot clinic. Compared with patients referred earlier, patients with a long time to referral (>3 months) were older (p=0.006) and had a less severe wound according to Infectious Diseases Society of America (IDSA) classification (p=0.003) and University of Texas classification (grade D=infection + peripheral artery disease, p=0.004).

CONCLUSION

The proportion of patients with a diabetic foot ulcer (DFU) referred to a specialised unit >3 months after the beginning of the ulcer remained high throughout Europe. Patients with severe DFU were, however, referred more quickly by front line health professionals. Primary care professionals need to be made aware of the importance of early referral to a specialised unit in order to improve the management of foot disease in patients with diabetes.

DECLARATION OF INTEREST

The authors have no conflicts of interest to declare.

Barriers to diabetic foot management in Italy: A multicentre survey in diabetic foot centres of the Diabetic Foot Study Group of the Italian Society of Diabetes (SID) and Association of Medical Diabetologists (AMD)

BACKGROUND AND AIMS

Diabetic foot (DF) disease is a current health and social burden. The authors aimed to identify the barriers to the DF management across Italy.

METHODS AND RESULTS

A questionnaire was submitted to Italian centres dedicated to DF care. The questionnaire was composed of 12 questions focused on the barriers to the DF management including timing of referral, hospital management, and community follow-up. Each centre could answer by choosing a score from 1 to 5 for every item with the following numerical variables: 1 = never; 2 = rarely; 3 = sometimes; 4 = often; 5 = always. Accordingly, for each item a national and regional score was reported and a comparison between regions was carried out. National and regional scores were estimated using the total score for each item as a numerator and the number of national centres included as a denominator. Among 102 centres, 99 were included and 3 were excluded due to missing data. The 99 centres belonged to 16 regions with the following distribution: Calabria 4, Campania 5, Emilia-Romagna 14, Friuli-Venezia-Giulia 4, Lazio 12, Liguria 4, Lombardy 10, Marche 1, Molise 1, Piedmont 5, Apulia 5, Sardinia 5, Sicily 4, Tuscany 11, Veneto 9, Umbria 5. The items with the highest score were late referral (3.3) and urgent surgery (3.2). The regions with the highest score were Molise (3.9) and Calabria (3.5).

CONCLUSION

The main issues across Italy were late referral and the requirement for urgent surgery for acute DF. In the regional scenario, the southern central areas showed more barriers than northern regions.

Changing the patterns of hospitalized diabetic foot ulcer (DFU) over a 5-year period in a multi-disciplinary setting in Thailand

BACKGROUND

After years of decline, the rate of amputations was reported to increase by 50% in the U.S. population between 2009 and 2015. Few studies have examined the most recent trends in hospitalized diabetic foot ulcer (DFU) in Asian patients. This study aimed to examine recent trends and outcomes in hospitalized DFU at a tertiary diabetes center in Bangkok.

METHODS

We conducted a retrospective study from consecutive hospitalized DFU admissions from 2014 to 2018 at Theptarin Hospital, a multi-disciplinary diabetes center, led by diabetologists.

RESULTS

During the study period, 290 patients (male 57.4%, age 65.5 ± 13.3 years, T2DM 99.4%, DM duration 18.8 ± 11.5 years, A1C 8.6 ± 2.3%) with 350 admissions were included. DFU were classified into neuropathic wounds (38.0%), ischemic wounds (2.6%), and mixed-type wounds (59.4%). The median length of stay was 8 days. Severe DFU (Wagner grade 3-5) composed 68.3% of all DFU and one-third of patients had prior history of amputations. Complete healing was achieved in 73.5% of the patients. Major amputation was performed in 16 (4.6%) and minor amputation was performed in 78 (22.3%) of all DFU. The mortality rate at 1 year after discharge was 12.0%. Advanced diseases with higher co-morbidities were associated with worse outcomes. When compared with our previous published data from 2009 to 2013, the annual rate of ischemic wounds from peripheral arterial diseases (PAD) and severity of DFU were increased in this study period. The major amputation rate slightly decreased from 6.0 to 4.6% but the minor amputation rate increased from 18.7 to 22.3%.

CONCLUSION

The changing trend of DFU provides an excellent outlook into the inadequacies of our current diabetes care systems and global trend of aging population. After considerable successes in reducing major amputations over the past decade, the current analysis revealed a discouraging change in the healing rate of DFU and a stable pattern of major amputation. The prevalence of PAD among Thai patients with DFU increased significantly and affected the results of DFU treatments. Redefined organization of care with multidisciplinary team approach and coordination with referral centers are urgently required to improve outcomes of DFU.

Charcot neuroarthropathy patient education among podiatrists in Scotland: a modified Delphi approach

Background

This evaluation sought to determine current Charcot neuroarthropathy (CN) diabetes patient education practices among Scottish National Health Service (NHS) and academic podiatrists and evaluate novel visual tools and develop expert consensus for future practice.

Methods

Questionnaires collected mixed qualitative and quantitative responses, analysed concurrently within a convergence coding matrix. Delphi methodology permitted member-checking and agreement of consensus over two rounds.

Results

Fourteen participants (16.28%) completed a Round One questionnaire, leading to the generation of four themes; Experience; Person-Centred Care and the Content and Context of CN patient education. Seven consensus statements were subsequently developed and six achieved over 80% agreement among 16 participants (18.60%) with a Round Two questionnaire. Respondents agreed CN patient education should be considered for all ‘At-risk’ individuals with diabetic peripheral neuropathy (DPN). Verbal metaphors, including the ‘rocker-bottom’ foot, soft or brittle bones, collapsing, walking on honeycomb and a shattering lightbulb were frequently employed. Visual tools, including visual metaphors and The Charcot Foot Thermometer, were positively evaluated and made available online.

Conclusions

Key findings included respondent’s belief that CN education should be considered for all individuals with DPN and the frequent use of simile, analogy and metaphor in CN education. The concept of ‘remission’ proved controversial due to its potential for misinterpretation.

Electronic supplementary material

The online version of this article (10.1186/s13047-018-0296-8) contains supplementary material, which is available to authorized users.

Real-Time Smart Textile-Based System to Monitor Pressure Offloading of Diabetic Foot Ulcers

BACKGROUND

The lifetime risk of developing a diabetic foot ulcer (DFU) is at least 25%. A DFU carries a 50% risk for infection and at least 20% of those receive some form of amputation. The most significant parameter that prevents or delays ulcer healing is high plantar pressure. To improve the patient's healing process, the DFU's plantar pressure should remain cumulatively low. Therefore, a tool that continuously measures the DFU loading, and provides real-time feedback can improve the healing outcome.

METHODS

We report the development of a system capable of continuously measuring the pressure, which could have applications to monitor DFU. The system contains a textile pressure sensor attached to a stretchable band, hardware that collects data and transmits them via Bluetooth to a phone, an app that gathers the data and stores them in the cloud, and a web dashboard that displays the data to the clinician. The sensor was characterized in vitro using the system, and the web-dashboard was developed and tested on simulated patient data.

RESULTS

We demonstrate the feasibility of developing the system and characterize the pressure response of the device. As a result, we demonstrate a viable method for monitoring DFU off-loading in real time.

CONCLUSIONS

The presented study demonstrates the feasibility to develop a simple, modular wearable system that opens up new possibilities for diabetic foot ulcer care by providing a way of monitoring the pressure under the ulcer in real time.

Plantar Fat Grafting and Tendon Balancing for the Diabetic Foot Ulcer in Remission

We report on the use of free fat grafting as a means of redistributing normal and shear stress after healing of plantar diabetic foot wounds. Although fat augmentation (lipofilling) has been described previously as an approach to supplement defects and prevent atrophy, including use as an adjunct to wound healing and to mitigate pain in the foot, we are unaware of any reports in the medical literature that have described its use in the high-risk diabetic foot in remission. An active 37-year-old man with type 2 diabetes and neuropathy presented with gangrene of his fifth ray, which was amputated. He subsequently developed a chronic styloid process ulceration that progressed despite treatment. We performed a tibialis anterior tendon transfer and total contact casting. He went on to heal but with residual fat pad atrophy and recalcitrant preulcerative lesions. We then used autologous fat grafting for the plantar atrophy. The patient was able to successfully transition to normal shoe gear after 4 weeks with successful engraftment without complication or recurrence of the wound at 6 weeks. This therapy may provide a promising adjunct to increase ulcer-free days to the patient in diabetic foot remission.

Toe-Sparing Surgery for Neuropathic Toe Ulcers With Exposed Bone or Joint in an Outpatient Setting

The purpose of this study was to review the results of aggressive surgical debridement of neuropathic toe ulcers with exposed bone or joint. We identified patients with a single toe ulcer with exposed bone or joint that had been operated on in an outpatient setting. The surgery had included aggressive debridement and was performed using a small curette and rongeur, followed by oral antibiotic treatment at home. Success was defined as complete healing with no recurrence 6 months after full wound closure and epitheliazation was achieved. Twenty-five patients with neuropathic toe ulcers (72% male) had a total of 26 primary operations. Their mean age was 60 ± 12 years. In 22 patients, the neuropathy resulted from diabetes mellitus of 17 ± 9 years’ duration. The mean ulcer duration was 6 weeks (range 1-24). The mean number of visits per patient was 6.5 (range 3-20). The ulcers closed in a median of 5 weeks (8 ± 6 weeks, range 3-24 weeks, Q1-Q3 4-10 weeks). At 6 months, 3 (11.5%) patients had needed a toe amputation for infection or necrosis that could not be controlled. None needed a major amputation or hospitalization related to the ulcer. Toe-sparing surgery is feasible and in a select population can have a high success rate (88%), even though it does dictate more dedicated patient care.

Implementation of foot thermometry plus mHealth to prevent diabetic foot ulcers: study protocol for a randomized controlled trial

Background

Diabetic foot neuropathy (DFN) is one of the most important complications of diabetes mellitus; its early diagnosis and intervention can prevent foot ulcers and the need for amputation. Thermometry, measuring the temperature of the feet, is a promising emerging modality for diabetic foot ulcer prevention. However, patient compliance with at-home monitoring is concerning. Delivering messages to remind patients to perform thermometry and foot care might be helpful to guarantee regular foot monitoring. This trial was designed to compare the incidence of diabetic foot ulcers (DFUs) between participants who receive thermometry alone and those who receive thermometry as well as mHealth (SMS and voice messaging) over a year-long study period.

Methods/design

This is an evaluator-blinded, randomized, 12-month trial. Individuals with a diagnosis of type 2 diabetes mellitus, aged between 18–80 years, having a present dorsalis pedis pulse in both feet, are in risk group 2 or 3 using the diabetic foot risk classification system (as specified by the International Working Group on the Diabetic Foot), have an operating cell phone or a caregiver with an operating cell phone, and have the ability to provide informed consent will be eligible to participate in the study. Recruitment will be performed in diabetes outpatient clinics at two Ministry of Health tertiary hospitals in Lima, Peru.

Interventions: participants in both groups will receive education about foot care at the beginning of the study and they will be provided with a thermometry device (TempStat™). TempStat™ is a tool that captures a thermal image of the feet, which, depending on the temperature of the feet, shows different colors. In this study, if a participant notes a single yellow image or variance between one foot and the contralateral foot, they will be prompted to notify a nurse to evaluate their activity within the previous 2 weeks and make appropriate recommendations. In addition to thermometry, participants in the intervention arm will receive an mHealth component in the form of SMS and voice messages as reminders to use the thermometry device, and instructions to promote foot care.

Outcomes: the primary outcome is foot ulceration, evaluated by a trained nurse, occurring at any point during the study.

Discussion

This study has two principal contributions towards the prevention of DFU. First, the introduction of messages to promote self-management of diabetes foot care as well as using reminders as a strategy to improve adherence to daily home-based measurements. Secondly, the implementation of a thermometry-based strategy complemented by SMS and voice messages in an LMIC setting, with wider implications for scalability.

Trial registration

This study is registered in ClinicalTrials.gov: Identifier NCT02373592.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1333-1) contains supplementary material, which is available to authorized users.

Real-time sonoelastography and ultrasound evaluation of the Achilles tendon in patients with diabetes with or without foot ulcers: a cross sectional study

BACKGROUND

Diabetes mellitus (DM) is an endocrine disease characterized by metabolic abnormalities and long-term complications. The Achilles tendon (AT) plays an important role in foot biomechanics. We aimed to investigate the effect of DM on the Achilles tendon, which may contribute to long-term complications in the foot-ankle complex.

METHODS

Seventy-eight patients with diabetes, with (35 patients, group I) or without (43 patients, group II) foot ulcers were recruited from the endocrinology clinic. Thirty-three age-, gender-, and BMI-matched healthy individuals were selected as controls. All participants underwent ultrasonography and sonoelastography of their AT in order to evaluate Achilles tendon thickness (ATT) and stiffness (ATS). Each patient was also tested for fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1C) as a measure of diabetes control. Other chronic complications were also evaluated in all patients with diabetes.

RESULTS

The AT was significantly thicker in group I compared to group II and the controls. HbA1C, FPG, and duration of diabetes were higher in group I. We observed that ATT was positively correlated with neuropathy, retinopathy, nephropathy, peripheral arterial disease and coronary arterial disease in group II while this correlation was not detected in group I. ATS was reduced in group I more than group II and control groups.

CONCLUSION

Changes in the structure of the AT may precede foot ankle disorders in patients with diabetes. This is the first study that reported the results of sonoelastosonography of AT in patients with diabetes and revealed the correlation between ATT and other chronic complications of diabetes.

Illustration of Cost Saving Implications of Lower Extremity Nerve Decompression to Prevent Recurrence of Diabetic Foot Ulceration

The US diabetic foot ulcer (DFU) incidence is 3-4% of 22.3 million diagnosed diabetes cases plus 6.3 million undiagnosed, 858 000 cases total. Risk of recurrence after healing is 30% annually. Lower extremity multiple nerve decompression (ND) surgery reduces neuropathic DFU (nDFU) recurrence risk by >80%. Cost effectiveness of hypothetical ND implementation to minimize nDFU recurrence is compared to the current $6.171 billion annual nDFU expense. A literature review identified best estimates of annual incidence, recurrence risk, medical management expense, and noneconomic costs for DFU. Illustrative cost/benefit calculations were performed assuming widespread application of bilateral ND after wound healing to the nDFU problem, using Center for Medicare Services mean expense data of $1143/case for unilateral lower extremity ND. Calculations use conservative, evidence-based cost figures, which are contemporary (2012) or adjusted for inflation. Widespread adoption of ND after nDFU healing could reduce annual DFU occurrences by at least 21% in the third year and 24% by year 5, representing calculated cost savings of $1.296 billion (year 3) to $1.481 billion (year 5). This scenario proffers significant expense reduction and societal benefit, and represents a minimum 1.9× return on the investment cost for surgical treatment. Further large cost savings would require reductions in initial DFU incidence, which ND might achieve by selective application to advanced diabetic sensorimotor polyneuropathy (DSPN). By minimizing the contribution of recurrences to yearly nDFU incidence, ND has potential to reduce by nearly $1 billion the annual cost of DFU treatment in the United States.