Measuring Plantar Tissue Stress in People With Diabetic Peripheral Neuropathy: A Critical Concept in Diabetic Foot Management

The rat as an animal model in chronic wound research: An update

The increasing global prevalence of chronic wounds underscores the growing importance of developing effective animal models for their study. This review offers a critical evaluation of the strengths and limitations of rat models frequently employed in chronic wound research and proposes potential improvements. It explores these models in the context of key comorbidities, including diabetes, venous and arterial insufficiency, pressure-induced blood flow obstruction, and infections. Additionally, the review examines important wound factors including age, sex, smoking, and the impact of anesthetic and analgesic drugs, acknowledging their substantial effects on research outcomes. A thorough understanding of these variables is crucial for refining animal models and can provide valuable insights for future research endeavors.

Plantar pressure measurement in diabetic foot disease: A scoping review

AIMS/INTRODUCTION

Patients with a healed diabetic foot ulcer (DFU) have a 40% risk of ulcer recurrence within a year. New and effective measures to prevent DFU recurrence are essential. We aimed to highlight emerging trends and future research opportunities in the use of plantar pressure measurement to prevent DFU recurrence.

MATERIALS AND METHODS

Our scoping review protocol was drafted using the Preferred Reporting Items for Systematic Reviews and Meta-analysis - Scoping Review protocol. Peer-reviewed, English-language papers were included that addressed both plantar pressure measurement and diabetic foot disease, either as primary studies that have advanced the field or as review papers that provide summaries and/or opinion on the field as a whole, as well as specific papers that provide guidelines for future research and advancement in the field.

RESULTS

A total of 24 eligible publications were identified in a literature search using PubMed. A further 36 eligible studies were included after searching the references sections of these publications, leaving a total of 60 publications included in this scoping review.

CONCLUSIONS

Plantar pressure measurement can and will play a major role in the prevention of DFU. There is already a strong, albeit limited, evidence base in place to prove its benefit in reducing DFU recurrence. More research is required in larger populations, using remote monitoring in real-world settings, and with improved technology.

The efficacy of custom-made offloading devices for diabetic foot ulcer prevention: a systematic review

INTRODUCTION

Therapeutic offloading devices, including insoles, shoes, and other orthoses, are some of the most commonly used interventions to treat or prevent diabetic foot ulceration. Custom-made offloading devices are increasingly used to offset the development of foot ulcers. However, whether these devices are more effective than prefabricated standard offloading devices is uncertain. Therefore, this systematic review collates and examines evidence on the efficacy of custom-made offloading devices in preventing foot ulcer incidence and recurrence in people diagnosed with diabetes.

METHODS

Five scientific databases were searched, covering 2011-2023. Initial searches and screening were carried out independently by two researchers. Studies meeting the inclusion criteria were further examined through additional screenings, and critical appraisal. Data relevant to the review aims were extracted and analysed within a narrative synthesis.

RESULTS

Of the 1,715 articles found in the initial searches, nine papers were found to meet inclusion criteria and were included in the review. The evidence shows that custom-made offloading devices are likely to be more effective for reducing or preventing diabetic foot ulcers than standard offloading devices. However, due to a lack of data it remains uncertain whether custom-made offloading devices are more cost-effective for preventing ulceration compared to standard insoles. Likewise, due to measurement heterogeneity between studies and lack of data, it is unclear whether adherence is higher in users of custom-made offloading devices, and whether such devices deliver significantly greater reductions in peak pressure as compared to standard offloading devices.

CONCLUSION

Custom-made offloading devices are more effective than standard devices for preventing diabetic foot ulceration, and we recommended their use when feasible; however, there remains uncertainty regarding their cost-effectiveness compared to standard insoles and offloading devices.

The Stress of Measuring Plantar Tissue Stress in People with Diabetes-Related Foot Ulcers: Biomechanical and Feasibility Findings from Two Prospective Cohort Studies

Reducing high mechanical stress is imperative to heal diabetes-related foot ulcers. We explored the association of cumulative plantar tissue stress (CPTS) and plantar foot ulcer healing, and the feasibility of measuring CPTS, in two prospective cohort studies (Australia (AU) and The Netherlands (NL)). Both studies used multiple sensors to measure factors to determine CPTS: plantar pressures, weight-bearing activities, and adherence to offloading treatments, with thermal stress response also measured to estimate shear stress in the AU-study. The primary outcome was ulcer healing at 12 weeks. Twenty-five participants were recruited: 13 in the AU-study and 12 in the NL-study. CPTS data were complete for five participants (38%) at baseline and one (8%) during follow-up in the AU-study, and one (8%) at baseline and zero (0%) during follow-up in the NL-study. Reasons for low completion at baseline were technical issues (AU-study: 31%, NL-study: 50%), non-adherent participants (15% and 8%) or combinations (15% and 33%); and at follow-up refusal of participants (62% and 25%). These underpowered findings showed that CPTS was non-significantly lower in people who healed compared with non-healed people (457 [117; 727], 679 [312; 1327] MPa·s/day). Current feasibility of CPTS seems low, given technical challenges and non-adherence, which may reflect the burden of treating diabetes-related foot ulcers.

The Why, What and Where Podcast on the Updated 2023 IWGDF Guideline on Offloading Treatments for Diabetes-Related Foot Ulcers

In this podcast the lead authors of the 2023 International Working Group on the Diabetic Foot (IWGDF) guideline on offloading treatments for diabetes-related foot ulcers briefly discuss why we need offloading treatments for people with diabetes-related foot ulcers, what the new international offloading guideline recommends, and where offloading treatment might go into the future.A podcast audio is available with this article.

Effectiveness of offloading interventions for people with diabetes-related foot ulcers: A systematic review and meta-analysis

BACKGROUND

Offloading treatment is crucial to heal diabetes-related foot ulcers (DFU). This systematic review aimed to assess the effectiveness of offloading interventions for people with DFU.

METHODS

We searched PubMed, EMBASE, Cochrane databases, and trials registries for all studies relating to offloading interventions in people with DFU to address 14 clinical question comparisons. Outcomes included ulcers healed, plantar pressure, weight-bearing activity, adherence, new lesions, falls, infections, amputations, quality of life, costs, cost-effectiveness, balance, and sustained healing. Included controlled studies were independently assessed for risk of bias and had key data extracted. Meta-analyses were performed when outcome data from studies could be pooled. Evidence statements were developed using the GRADE approach when outcome data existed.

RESULTS

From 19,923 studies screened, 194 eligible studies were identified (47 controlled, 147 non-controlled), 35 meta-analyses performed, and 128 evidence statements developed. We found non-removable offloading devices likely increase ulcers healed compared to removable offloading devices (risk ratio [RR] 1.24, 95% CI 1.09-1.41; N = 14, n = 1083), and may increase adherence, cost-effectiveness and decrease infections, but may increase new lesions. Removable knee-high offloading devices may make little difference to ulcers healed compared to removable ankle-high offloading devices (RR 1.00, 0.86-1.16; N = 6, n = 439), but may decrease plantar pressure and adherence. Any offloading device may increase ulcers healed (RR 1.39, 0.89-2.18; N = 5, n = 235) and cost-effectiveness compared to therapeutic footwear and may decrease plantar pressure and infections. Digital flexor tenotomies with offloading devices likely increase ulcers healed (RR 2.43, 1.05-5.59; N = 1, n = 16) and sustained healing compared to devices alone, and may decrease plantar pressure and infections, but may increase new transfer lesions. Achilles tendon lengthening with offloading devices likely increase ulcers healed (RR 1.10, 0.97-1.27; N = 1, n = 64) and sustained healing compared to devices alone, but likely increase new heel ulcers.

CONCLUSIONS

Non-removable offloading devices are likely superior to all other offloading interventions to heal most plantar DFU. Digital flexor tenotomies and Achilles tendon lengthening in combination with offloading devices are likely superior for some specific plantar DFU locations. Otherwise, any offloading device is probably superior to therapeutic footwear and other non-surgical offloading interventions to heal most plantar DFU. However, all these interventions have low-to-moderate certainty of evidence supporting their outcomes and more high-quality trials are needed to improve our certainty for the effectiveness of most offloading interventions.

The quest for wellness: How to optimise self-care strategies for diabetic foot management?

Diabetic foot ulceration (DFU) is common and highly recurrent, negatively impacting the individuals' quality of life. The 2023 guidelines of the International Working Group on the Diabetic Foot emphasise that adherence to foot self-care recommendations is one of the most important factors in DFU prevention. These guidelines also briefly mention that depression and other psychosocial problems can hamper treatment and ulcer healing. Moreover, a new clinical question was added on psychological interventions for ulcer prevention, although the evidence regarding the role of psychological and social factors is still limited. To help the field progress, this narrative overview discusses how a stronger focus on psychological factors by both researchers and clinicians could improve the care for people at high DFU risk. The review starts with a testimony of a person living with DFU, explaining that for him, the absence of shared decision-making has been a key barrier to successful foot self-care implementation. Intervention studies that address patient-reported barriers are still scarce, and are therefore urgently needed. Furthermore, the key elements of psychological interventions found to be successful in managing diabetes are yet to be implemented in DFU risk management. Importantly, research evidence indicates that commonly advocated foot self-care recommendations may be insufficient in preventing DFU recurrence, whereas digital technology appears to effectively reduce recurrent DFU. More research is therefore needed to identify determinants of patient acceptance of digital technology.

Guidelines on offloading foot ulcers in persons with diabetes (IWGDF 2023 update)

AIMS

Offloading mechanical tissue stress is arguably the most important of multiple interventions needed to heal diabetes-related foot ulcers. This is the 2023 International Working Group on the Diabetic Foot (IWGDF) evidence-based guideline on offloading interventions to promote healing of foot ulcers in persons with diabetes. It serves as an update of the 2019 IWGDF guideline.

MATERIALS AND METHODS

We followed the GRADE approach by devising clinical questions and important outcomes in the PICO (Patient-Intervention-Control-Outcome) format, undertaking a systematic review and meta-analyses, developing summary of judgement tables and writing recommendations and rationales for each question. Each recommendation is based on the evidence found in the systematic review, expert opinion where evidence was not available, and a careful weighing of GRADE summary of judgement items including desirable and undesirable effects, certainty of evidence, patient values, resources required, cost effectiveness, equity, feasibility, and acceptability.

RESULTS

For healing a neuropathic plantar forefoot or midfoot ulcer in a person with diabetes, use a non-removable knee-high offloading device as the first-choice offloading intervention. If contraindications or patient intolerance to non-removable offloading exist, consider using a removable knee-high or ankle-high offloading device as the second-choice offloading intervention. If no offloading devices are available, consider using appropriately fitting footwear combined with felted foam as the third-choice offloading intervention. If such a non-surgical offloading treatment fails to heal a plantar forefoot ulcer, consider an Achilles tendon lengthening, metatarsal head resection, joint arthroplasty, or metatarsal osteotomy. For healing a neuropathic plantar or apex lesser digit ulcer secondary to flexibile toe deformity, use digital flexor tendon tenotomy. For healing rearfoot, non-plantar or ulcers complicated with infection or ischaemia, further recommendations have been outlined. All recommendations have been summarised in an offloading clinical pathway to help facilitate the implementation of this guideline into clinical practice.

CONCLUSION

These offloading guideline recommendations should help healthcare professionals provide the best care and outcomes for persons with diabetes-related foot ulcers and reduce the person's risk of infection, hospitalisation and amputation.

Guidelines on the prevention of foot ulcers in persons with diabetes (IWGDF 2023 update)

AIMS

This is the 2023 International Working Group on the Diabetic Foot guideline on the prevention of foot ulcers in persons with diabetes, which updates the 2019 guideline. This guideline is targeted at clinicians and other healthcare professionals.

MATERIALS AND METHODS

We followed the Grading of Recommendations, Assessment, Development and Evaluations methodology to devise clinical questions and critically important outcomes in the PICO format, to conduct a systematic review of the medical-scientific literature including, where appropriate, meta-analyses, and to write recommendations and their rationale. The recommendations are based on the quality of evidence found in the systematic review, expert opinion where (sufficient) evidence was not available, and a weighing of the desirable and undesirable effects of an intervention, as well as patient preferences, costs, equity, feasibility and applicability.

RESULTS

We recommend screening a person with diabetes at very low risk of foot ulceration annually for the loss of protective sensation and peripheral artery disease, and screening persons at higher risk at higher frequencies for additional risk factors. For preventing a foot ulcer, educate persons at-risk about appropriate foot self-care, educate not to walk without suitable foot protection, and treat any pre-ulcerative lesion on the foot. Educate moderate-to-high risk people with diabetes to wear properly fitting, accommodative, therapeutic footwear, and consider coaching them to monitor foot skin temperature. Prescribe therapeutic footwear that has a demonstrated plantar pressure relieving effect during walking, to help prevent plantar foot ulcer recurrence. Consider advising people at low-to-moderate risk to undertake a, preferably supervised, foot-ankle exercise programme to reduce ulcer risk factors, and consider communicating that a total increase in weight-bearing activity of 1000 steps/day is likely safe with regards to risk of ulceration. In people with non-rigid hammertoe with pre-ulcerative lesion, consider flexor tendon tenotomy. We suggest not to use a nerve decompression procedure to help prevent foot ulcers. Provide integrated foot care for moderate-to-high-risk people with diabetes to help prevent (recurrence of) ulceration.

CONCLUSIONS

These recommendations should help healthcare professionals to provide better care for persons with diabetes at risk of foot ulceration, to increase the number of ulcer-free days and reduce the patient and healthcare burden of diabetes-related foot disease.

New biomechanical models for cumulative plantar tissue stress assessment in people with diabetes at high risk of foot ulceration

To better understand stress-related foot ulceration in diabetes, the cumulative plantar tissue stress (CPTS) should be quantified accurately, but also feasibly for clinical use. We developed multiple CPTS models with varying complexity and investigated their agreement with the most comprehensive reference model available. We assessed 52 participants with diabetes and high foot ulcer risk for barefoot and in-shoe plantar pressures during overground walking at different speeds, standing, sit-to-stand transitions, and stair walking. Level of these weight-bearing activities along with footwear adherence were objectively measured over seven days. The reference CPTS-model included the pressure-time integrals of each walking stride (barefoot and shod), specified for speed; standing period (barefoot and shod); transition and stair walking stride. We compared four CPTS-models with increasing number of input parameters (models 1-4) with the reference model, using repeated measures ANOVA, Pearson's correlation and Bland-Altman plots. For the clinically-relevant metatarsal 1 region, calculated CPTS was lower for the four CPTS-models compared to reference (Δ770, Δ466, Δ24 and Δ12 MPa.s/day, respectively). CPTS associated moderately with the reference model for model 1 (r = 0.551) and very strongly for models 2-4 (r ≥ 0.937). Limits of agreement were large for models 1 and 2 (-728;2269 and -302;1233 MPa.s/day), and small for models 3 and 4 (-43;92 and -54;78 MPa.s/day). CPTS in models 3 and 4 best agreed with the reference model, where model 3 required fewer parameters, i.e., pressure-time integrals of each walking stride and standing period while barefoot and shod. These parameters need to be included for accurate and feasible CPTS assessment.

Effects of individually optimized rocker midsoles and self-adjusting insoles on plantar pressure in persons with diabetes mellitus and loss of protective sensation

INTRODUCTION

Rocker shoes and insoles reduce peak pressure (PP) in persons with diabetes (DM) and loss of protective sensation (LOPS). However, they are handmade, leading to inconsistent effectiveness. If foot structure changes over time, high PP-locations also change. To address this, individualized algorithm based 3D-printed rockers and self-adjusting pressure-reducing insoles are applied.

METHODS

PP across seven foot regions was analyzed in 21 persons with DM and LOPS. Regions with PP < 200 kPa were considered not at risk (RnoR); regions with PP ≥ 200 kPa at risk (RaR). The aim was to offload RaR, while remaining PP < 200 kPa in RnoR.

RESULTS

Individualized rockers and self-adjusting insoles combined successfully reduce PP < 200 kPa (on average 24 % - 48 %) in all feet with toes, central and lateral forefoot identified as RaR. Same intervention reduces PP in 68 % of the feet with medial forefoot identified as RaR. With the heel as RaR, no intervention reduces PP successfully in all feet.

CONCLUSIONS

Individualized 3D-printed rockers combined with self-adjusting insoles reduce PP (< 200 kPa) in toes, central and lateral forefoot, but not in heels. Alternative insoles with medial arch support, heel cup and compliant midsole materials might enhance success rate across entire foot.

Adherence to limiting weight-bearing activity in patients with diabetic foot ulcers: A qualitative study

Patients with diabetic foot ulcers are advised to limit weight-bearing activity for ulcers to heal. Patients often disregard this advice although the reasons are not yet fully understood. This study explored (1) patients' experiences of receiving the advice and (2) factors influencing adherence to the advice. Semi-structured interviews were conducted with 14 patients with diabetic foot ulcers. Interviews were transcribed and analysed using inductive thematic analysis. Advice regarding limiting weight-bearing activity was described by patients as directive, generic and conflicting with other priorities. Rapport, empathy and rationale supported receptivity to the advice. Barriers and facilitators to limiting weight-bearing activity included demands of daily living, enjoyment of exercise, sick/disabled identity and burden, depression, neuropathy/pain, health benefits, fear of negative consequences, positive feedback, practical support, weather and active/passive role in recovery. It is important that healthcare professionals pay attention to how limiting weight-bearing activity advice is communicated. We propose a more person-centred approach in which advice is tailored to individuals' specific needs with discussion around patient priorities and constraints.

The Validity and Reliability of the SINBAD Classification System for Diabetic Foot Ulcers

ABSTRACT

Diabetic foot ulcers (DFUs) are a serious and costly complication of diabetes mellitus with a global prevalence of 6.3% and cost of £8,800 per unhealed DFU in the National Health Service. The three main types of DFU are neuropathic, ischemic, and neuroischemic, with an estimated prevalence of 35%, 15%, and 50%, respectively. Because 85% of lower-limb amputations in patients with diabetes are preceded by a DFU, the task of reducing the current and future burden of DFUs on an international level is of crucial importance. Classification of a DFU is an important and complex process with many independent variables that influence the wound severity. Correct classification of a DFU is important to prevent deterioration in the short term and lower-limb amputation in the long term. Both the accuracy of the clinician's interpretation of categorical data from a classification model and grasp of contextual risk factors can refine diagnoses. The term SINBAD is an acronym for six independent variables: site, ischemia, neuropathy, bacterial infection, area, and depth. This system uses comprehensive parameters with strict criteria to facilitate quick and accurate clinical decisions to prevent lower-limb amputation. In addition to providing quantitative measurement, SINBAD also spotlights the multifaceted characteristics of DFUs. By evaluating the validity and reliability of the SINBAD classification system, its applicability for the assessment of DFUs and prevention of lower-limb amputation can be better understood.

An integrated personalized assistive devices approach to reduce the risk of foot ulcer recurrence in diabetes (DIASSIST): study protocol for a multicenter randomized controlled trial

BACKGROUND

Preventing foot ulcers in people with diabetes can increase quality of life and reduce costs. Despite the availability of various interventions to prevent foot ulcers, recurrence rates remain high. We hypothesize that a multimodal treatment approach incorporating various footwear, self-management, and education interventions that matches an individual person's needs can reduce the risk of ulcer recurrence with beneficial cost-utility. The aim of this study is to assess the effect on foot ulcer recurrence, footwear adherence, and cost-utility of an integrated personalized assistive devices approach in high-risk people with diabetes.

METHODS

In a parallel-group multicenter randomized controlled trial, 126 adult participants with diabetes mellitus type 1 or 2, loss of protective sensation based on the presence of peripheral neuropathy, a healed plantar foot ulcer in the preceding 4 years, and possession of any type of custom-made footwear will be included. Participants will be randomly assigned to either enhanced therapy or usual care. Enhanced therapy consists of usual care and additionally a personalized treatment approach including pressure-optimized custom-made footwear, pressure-optimized custom-made footwear for indoor use, at-home daily foot temperature monitoring, and structured education, which includes motivational interviewing and personalized feedback on adherence and self-care. Participants will be followed for 12 months. Assessments include barefoot and in-shoe plantar pressure measurements; questionnaires concerning quality of life, costs, disease, and self-care knowledge; physical activity and footwear use monitoring; and clinical monitoring for foot ulcer outcomes. The study is powered for 3 primary outcomes: foot ulcer recurrence, footwear adherence, and cost-utility, the primary clinical, patient-related, and health-economic outcome respectively.

DISCUSSION

This is the first study to integrate multiple interventions for ulcer prevention into a personalized state-of-the-art treatment approach and assess their combined efficacy in a randomized controlled trial in people with diabetes at high ulcer risk. Proven effectiveness, usability, and cost-utility will facilitate implementation in healthcare, improve the quality of life of high-risk people with diabetes, and reduce treatment costs.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05236660. Registered on 11 February 2022.

A qualitative exploration of adherence to wearing removable cast walkers in patients with diabetic foot ulcers

OBJECTIVE

To explore adherence to wearing removable cast walkers (RCWs) among patients with diabetic foot ulcers (DFUs).

METHOD

A qualitative study was conducted by interviewing patients with active DFUs and using knee-high RCWs as their offloading treatment. The interviews were undertaken at two diabetic foot clinics in Jordan, using a semi-structured guide. Data were analysed through content analysis by developing main themes and categories.

RESULTS

Following interviews with 10 patients, two main key themes with a total of six categories were identified: theme 1-reporting of adherence levels was inconsistent, included two categories: i) a belief in achieving optimal adherence, and ii) non-adherence was often reported indoors; and theme 2-adherence was a consequence of multiple psychosocial, physiological and environmental factors, which included four categories: i) specific offloading knowledge or beliefs influenced adherence; ii) severity of foot disease influenced adherence; iii) social support benefitted adherence; and iv) physical features of RCWs (the usability of the offloading device) impacted adherence.

CONCLUSION

Patients with active DFUs reported inconsistent levels of adherence to wearing RCWs which, after deeper investigation, seemed to be due to participants' misperceptions of the optimal adherence. Adherence to wearing RCWs also seemed to be impacted by multiple psychosocial, physiological and environmental factors.

Recent Advances in Flexible Piezoresistive Arrays: Materials, Design, and Applications

Spatial distribution perception has become an important trend for flexible pressure sensors, which endows wearable health devices, bionic robots, and human-machine interactive interfaces (HMI) with more precise tactile perception capabilities. Flexible pressure sensor arrays can monitor and extract abundant health information to assist in medical detection and diagnosis. Bionic robots and HMI with higher tactile perception abilities will maximize the freedom of human hands. Flexible arrays based on piezoresistive mechanisms have been extensively researched due to the high performance of pressure-sensing properties and simple readout principles. This review summarizes multiple considerations in the design of flexible piezoresistive arrays and recent advances in their development. First, frequently used piezoresistive materials and microstructures are introduced in which various strategies to improve sensor performance are presented. Second, pressure sensor arrays with spatial distribution perception capability are discussed emphatically. Crosstalk is a particular concern for sensor arrays, where mechanical and electrical sources of crosstalk issues and the corresponding solutions are highlighted. Third, several processing methods are also introduced, classified as printing, field-assisted and laser-assisted fabrication. Next, the representative application works of flexible piezoresistive arrays are provided, including human-interactive systems, healthcare devices, and some other scenarios. Finally, outlooks on the development of piezoresistive arrays are given.

Neuropathy in paediatric type 1 diabetes mellitus - clinical characterization and analysis of risk factors in the diabetes prospective follow-up registry DPV (Diabetes-Patienten-Verlaufsdokumentation)-registry

OBJECTIVES

Data on the prevalence, clinical features and risk factors associated with paediatric diabetic neuropathy (DN) are scarce.

METHODS

We retrospectively analysed data from the DPV registry, including patients under 20 years of age, treated for type 1 diabetes mellitus (T1D) between 2005 and 2021. Patients with non-diabetic neuropathy were excluded. Data came from centres in Austria, Germany, Luxembourg and Switzerland.

RESULTS

1,121 of the 84,390 patients included had been diagnosed with DN. Univariate analysis showed patients with DN to be older and predominantly female, with a longer duration of T1D, higher insulin dosages per kg and day, lower rates of insulin pump therapy, higher postprandial glucose-, higher HbA_1c-and higher cholesterol levels, and higher diastolic and systolic blood pressure values. There was also a larger proportion of smokers and higher prevalence of diabetic retinopathy. Median duration of diabetes at diagnosis of DN was 8.3 years. Multivariable analysis, adjusted for demographics revealed an increased risk for DN among female patients and those who were older, underweight (BMI-SDS), smoked cigarettes or had a longer duration of T1D or higher levels of HbA_1c and postprandial blood glucose. The presence of retinopathy and higher cholesterol levels were also linked to increased risk while not-using insulin pump therapy was not.

CONCLUSIONS

DN can develop after just a short duration of T1D. Prevention may be achieved by a lowering of HbA_1c-and postprandial glucose levels through improved glycaemic control. This warrants further investigation. The slight female predominance suggests further hormonal and genetic etiological factors.

Offloading effects of a removable cast walker with and without modification for diabetes-related foot ulceration: a plantar pressure study

BACKGROUND

Removable cast walkers (RCWs), with or without modifications, are used to offload diabetes-related foot ulcers (DRFUs), however there is limited data relating to their offloading effects. This study aimed to quantify plantar pressure reductions with an RCW with and without modification for DRFUs.

METHODS

This within-participant, repeated measures study included 16 participants with plantar neuropathic DRFUs. Walking peak plantar pressures at DRFU sites were measured for four conditions: post-operative boot (control condition), RCW alone, RCW with 20 mm of felt adhered to an orthosis, and RCW with 20 mm of felt adhered to the foot.

RESULTS

Compared to the control condition, the greatest amount of peak plantar pressure reduction occurred with the RCW with felt adhered to the foot (83.1% reduction, p < .001). The RCW with felt adhered to the foot also offered greater peak plantar pressure reduction than the RCW alone (51.3%, p = .021) and the RCW with felt adhered to an orthosis (31.4%, p = .009).

CONCLUSION

The largest offloading effect recorded was with the RCW with felt adhered to the foot. High-quality randomised trials are now needed to evaluate the effectiveness of this device for healing DRFUs.

The Validity and Reliability of Self-Reported Adherence to Using Offloading Treatment in People with Diabetes-Related Foot Ulcers

Adherence to using offloading treatment is crucial to healing diabetes-related foot ulcers (DFUs). Offloading adherence is recommended to be measured using objective monitors. However, self-reported adherence is commonly used and has unknown validity and reliability. This study aimed to assess the validity and reliability of self-reported adherence to using removable cast walker (RCW) offloading treatment among people with DFUs. Fifty-three participants with DFUs using RCWs were included. Each participant self-reported their percentage adherence to using their RCW of total daily steps. Participants also had adherence objectively measured using dual activity monitors. After one week, a subset of 19 participants again self-reported their percentage adherence to investigate test-retest reliability. Validity was tested using Pearson's r and Bland-Altman tests, and reliability using Cohen's kappa. Median (IQR) self-reported adherence was greater than objectively measured adherence (90% (60-100) vs. 35% (19-47), p < 0.01). There was fair agreement (r = 0.46; p < 0.01) and large 95% limits of agreement with significant proportional bias (β = 0.46, p < 0.01) for validity, and minimal agreement for test-retest reliability (K = 0.36; p < 0.01). The validity and reliability of self-reported offloading adherence in people with DFU are fair at best. People with DFU significantly overestimate their offloading adherence. Clinicians and researchers should instead use objective adherence measures.

In-shoe plantar pressure depends on walking speed and type of weight-bearing activity in people with diabetes at high risk of foot ulceration

BACKGROUND

In evaluating therapeutic footwear, in-shoe plantar pressure is usually obtained during mid-gait steps at self-selected walking speed in a laboratory setting. However, this may not accurately represent plantar pressures or indicate the cumulative stress experienced in daily life. We investigated the effects of walking speed and different weight-bearing activities on in-shoe plantar pressure in people with diabetes at high risk of ulceration.

METHODS

In a cross-sectional study including 30 participants we compared in-shoe plantar pressures between three standardized walking speeds (0.8, 0.6 and 0.4 m/s) and between walking at self-selected speed and eight other weight-bearing activities (3 components of the Timed Up and Go test, accelerating, decelerating, stair ascending and descending, and standing). Mean forefoot regional peak plantar pressure and pressure-time integral were statistically assessed per foot using linear mixed models (α < 0.05) with Holm-Bonferroni correction.

FINDINGS

With increasing walking speed, peak pressures increased and pressure-time integrals decreased (P ≤ 0.014). Peak pressures during standing, decelerating, stair ascending and Timed Up and Go test were lower (P ≤ 0.001), and with other activities not different to walking at self-selected speed. Pressure-time integrals during stair ascending and descending were higher (P ≤ 0.001), during standing lower (P ≤ 0.009), and with other activities not different to walking at self-selected speed.

INTERPRETATION

In-shoe plantar pressure depends on walking speed and type of weight-bearing activity. Only measuring pressures to evaluate footwear at self-selected walking speed in a laboratory setting may not accurately represent the stress on the foot in daily life of the high-risk patient; a more comprehensive assessment is suggested.

Taking a Load Off: User Perceptions of Smart Offloading Walkers for Diabetic Foot Ulcers Using the Technology Acceptance Model

People with diabetic foot ulcers (DFUs) are commonly prescribed offloading walkers, but inadequate adherence to prescribed use can be a barrier to ulcer healing. This study examined user perspectives of offloading walkers to provide insight on ways to help promote adherence. Participants were randomized to wear: (1) irremovable, (2) removable, or (3) smart removable walkers (smart boot) that provided feedback on adherence and daily walking. Participants completed a 15-item questionnaire based on the Technology Acceptance Model (TAM). Spearman correlations assessed associations between TAM ratings with participant characteristics. Chi-squared tests compared TAM ratings between ethnicities, as well as 12-month retrospective fall status. A total of 21 adults with DFU (age 61.5 ± 11.8 years) participated. Smart boot users reported that learning how to use the boot was easy (ρ =-0.82, p≤ 0.001). Regardless of group, people who identified as Hispanic or Latino, compared to those who did not, reported they liked using the smart boot (p = 0.05) and would use it in the future (p = 0.04). Non-fallers, compared to fallers, reported the design of the smart boot made them want to wear it longer (p = 0.04) and it was easy to take on and off (p = 0.04). Our findings can help inform considerations for patient education and design of offloading walkers for DFUs.

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.

Does the skin heat up before it breaks down in diabetic foot ulceration?

AIMS

Most diabetic foot ulcers are caused by tissue stress from being ambulatory in people without protective sensation. These ulcers are suggested to be preceded by local skin temperature increase due to inflammation of the underlying tissue, a so-called hotspot. Evidence to support this mechanism of ulcer development is meagre at best. We investigated if foot ulcers are preceded by increased skin temperature in people with diabetes and foot ulcer history.

MATERIAL AND METHODS

Participants measured temperature at 6-8 plantar foot locations each day for 18 months and identified a hotspot with a temperature difference >2.2°C between corresponding foot locations for two consecutive days.

RESULTS

Twenty-nine of 151 participants developed a non-traumatic ulcer while adhering to temperature measurements. In the 2 months prior to ulceration, 8 (28%) had a true hotspot (i.e. at/adjacent to the ulcer location) and the hotspot was on average no longer present 9 days before ulceration. Seven (24%) participants had a false hotspot (i.e. at another location) and 14 (48%) had no hotspot.

CONCLUSIONS

The skin of the majority of the ulcers does not heat up before it breaks down or, when it does, not directly before breakdown, questioning the foot temperature increase-uslcer association.

Adherence and Wearing Time of Prescribed Footwear among People at Risk of Diabetes-Related Foot Ulcers: Which Measure to Use?

Adherence to prescribed footwear is essential to prevent diabetes-related foot ulcers. The aim was to compare different measures of adherence and wearing time of prescribed footwear with a reference adherence measure, among people with diabetes at high risk of foot ulceration. We followed 53 participants for 7 consecutive days. A temperature sensor measured wearing time of prescribed footwear and a triaxial accelerometer assessed weight-bearing activities. Subjective wearing time was self-reported. Reference adherence measure was proportion of weight-bearing time prescribed footwear was worn. We calculated Spearman's correlation coefficients, kappa coefficients, and areas under the curve (AUC) for the association between the reference measure and other measures of adherence and wearing time. Proportion of daily steps with prescribed footwear worn had a very strong association (r = 0.96, Κ = 0.93; AUC: 0.96-1.00), objective wearing time had a strong association (r = 0.91, Κ = 0.85, AUC: 0.89-0.99), and subjective wearing time had a weak association (r = 0.42, Κ = 0.38, AUC: 0.67-0.81) with the reference measure. Objectively measured proportion of daily steps with prescribed footwear is a valid measure of footwear adherence. Objective wearing time is reasonably valid, and may be used in clinical practice and for long-term measurements. Subjective wearing time is not recommended to be used.

Personalized Offloading Treatments for Healing Plantar Diabetic Foot Ulcers

BACKGROUND

Non-removable knee-high devices are the gold-standard offloading treatments to heal plantar diabetic foot ulcers (DFUs). These devices are underused in practice for a variety of reasons. Recommending these devices for all patients, regardless of their circumstances and preferences influencing their ability to tolerate the devices, does not seem a fruitful approach.

PURPOSE

The aim of this article is to explore the potential implications of a more personalized approach to offloading DFUs and suggest avenues for future research and development.

METHODS

Non-removable knee-high devices effectively heal plantar DFUs by reducing plantar pressure and shear at the DFU, reducing weight-bearing activity and enforcing high adherence. We propose that future offloading devices should be developed that aim to optimize these mechanisms according to each individual's needs. We suggest three different approaches may be developed to achieve such personalized offloading treatment. First, we suggest modular devices, where different mechanical features (rocker-bottom sole, knee-high cast walls/struts, etc.) can be added or removed from the device to accommodate different patients' needs and the evolving needs of the patient throughout the treatment period. Second, advanced manufacturing techniques and novel materials could be used to personalize the design of their devices, thereby improving common hindrances to their use, such as devices being heavy, bulky, and hot. Third, sensors could be used to provide real-time feedback to patients and clinicians on plantar pressures, shear, weight-bearing activity, and adherence.

CONCLUSIONS

By the use of these approaches, we could provide patients with personalized devices to optimize plantar tissue stress, thereby improving clinical outcomes.

Accuracy of Foot Pressure Measurement on Predicting the Development of Foot Ulcer in Patients with Diabetes: A Systematic Review and Meta-Analysis

OBJECTIVE

Areas of the foot with diabetic ulcers have been observed to have greater plantar pressures compared to non-ulcerated. Pressures play an essential role in the mechanism of lesion, and their reduction is effective in prevention. We conducted a systematic review to evaluate pedobarography as a predictive tool for ulcer development, since there is still no consensus on this aspect.

METHODS

We searched PUBMED (MedLine), EMBASE, Scopus, Web of Science, CINAHL and Scielo for cohort studies that measured plantar pressure at baseline and verified ulcer development on follow-up. Pooled effects of accuracy, sensitivity, specificity and relative risk were calculated using the inverse variance method. Risk of bias was assessed using the QUADAS-2 tool.

RESULTS

Three studies (n = 2000) had enough information on accuracy to be included into a meta-analysis, and 4 (n = 2651) were analyzed using qualitative methods. Pooled sensitivity and specificity were found to be 0.63 (Confidence Interval (CI) 0.58-0.68) and 0.42 (CI 0.27-0.58), respectively. Pooled relative risk was 1.95 (CI 1.09-3.51). Risk of bias was low to uncertain.

CONCLUSIONS

Pedobarography in itself appears to have low accuracy in evaluating risk of ulceration. Several methodological heterogeneities were found, and the most optimal cut-off value is yet to be determined.

Differences in adherence to using removable cast walker treatment during daytime and nighttime weight-bearing activities in people with diabetes-related foot ulcers

AIMS

Patients' adherence to using knee-high offloading treatment is critical to effective healing of diabetes-related foot ulcers (DFUs). Previous studies have found that patients generally have low adherence to using removable knee-high offloading treatments, yet no study has investigated whether their adherence differs during daytime and nighttime. This study aimed to investigate the levels and factors associated with adherence to using knee-high removable cast walker (RCW) treatment during daytime and nighttime weight-bearing activities in people with DFUs.

METHODS

This was a secondary analysis of data collected from a multi-centre cross-sectional study investigating adherence to using knee-high RCWs among 57 participants with DFUs. All participants had multiple socio-demographic, physiological and psychosocial factors collected, before having their adherence to using RCWs during weight-bearing activity monitored over a 1-week period using the dual activity monitor method. Adherence data were categorised into daytime (06:00-18:00) and nighttime (18:00-06:00) periods and calculated separately. Multiple linear regression was used to identify factors associated with daytime and nighttime adherence.

RESULTS

Mean adherence to using RCW during weight-bearing activities in people with DFUs was higher during daytime compared with nighttime [39.9% (SD = 18.9) versus 20.4% (SD = 16.7), p < 0.001]. Factors independently associated with lower adherence during daytime were being male, longer diabetes duration, not having peripheral artery disease (PAD), and higher perceived RCW heaviness. Factors associated with lower adherence during nighttime were higher mean daytime steps, not having retinopathy and having dyslipidaemia.

CONCLUSIONS

Adherence to using RCWs during weight-bearing activities reduced significantly at nighttime compared with daytime among people with DFUs, and this was associated with different factors. Interventions to improve adherence, in research and clinical practice, should incorporate methods to target daytime or nighttime adherence specifically.

Users' needs and expectations and the design of a new custom-made indoor footwear solution for people with diabetes at risk of foot ulceration

PURPOSE

To assess users' needs and expectations regarding custom-made indoor footwear, and to design such footwear with similar biomechanical efficacy and better usability compared to regular custom-made footwear in people with diabetes at risk for foot ulceration.

MATERIALS AND METHODS

Multidisciplinary systematic design approach. Needs and expectations regarding indoor footwear were evaluated via a questionnaire in 50 high foot ulcer risk people with diabetes using custom-made footwear. We systematically designed indoor footwear, and manufactured this for nine participants. Primary requirement was similar plantar pressure compared to participants' regular custom-made footwear.

RESULTS

Eighty-two percent of participants expressed a need for custom-made indoor footwear and 66% expected such footwear to increase their adherence. The custom-made indoor footwear had the same bottom construction as participants' regular custom-made footwear, but with softer and more light-weight upper materials. Peak pressures were similar or lower, while qualitative evaluation showed better usability and lower costs for indoor footwear.

CONCLUSIONS

People with diabetes at risk of foot ulceration expressed a clear need for custom-made indoor footwear, and expected such footwear to increase their adherence. Our indoor footwear design provides adequate pressure relief, with better usability, and can be produced at lower costs compared to regular custom-made footwear.Implications for rehabilitationPeople with diabetes at risk of foot ulceration express a need for special indoor footwear.We developed indoor footwear with similar offloading capacity as regular custom-made footwear.The indoor footwear is lighter in weight, easier to don/doff and lower in costs.At-risk people with diabetes expect this footwear to increase their footwear adherence.

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.

Digital Biomarkers of Gait and Balance in Diabetic Foot, Measurable by Wearable Inertial Measurement Units: A Mini Review

People with diabetic foot frequently exhibit gait and balance dysfunction. Recent advances in wearable inertial measurement units (IMUs) enable to assess some of the gait and balance dysfunction associated with diabetic foot (i.e., digital biomarkers of gait and balance). However, there is no review to inform digital biomarkers of gait and balance dysfunction related to diabetic foot, measurable by wearable IMUs (e.g., what gait and balance parameters can wearable IMUs collect? Are the measurements repeatable?). Accordingly, we conducted a web-based, mini review using PubMed. Our search was limited to human subjects and English-written papers published in peer-reviewed journals. We identified 20 papers in this mini review. We found preliminary evidence of digital biomarkers of gait and balance dysfunction in people with diabetic foot, such as slow gait speed, large gait variability, unstable gait initiation, and large body sway. However, due to heterogeneities in included papers in terms of study design, movement tasks, and small sample size, more studies are recommended to confirm this preliminary evidence. Additionally, based on our mini review, we recommend establishing appropriate strategies to successfully incorporate wearable-based assessment into clinical practice for diabetic foot care.

Weight-bearing physical activity in people with diabetes-related foot disease: A systematic review

INTRODUCTION

Weight-bearing physical activity is important for people with diabetes-related foot disease but may also contribute to ulceration or delayed ulcer healing. No overview of weight-bearing activity of people at different stages of foot disease is available. We aimed to summarise quantitatively measured daily activity levels in people with diabetes-related foot disease.

METHODS

We systematically searched peer-reviewed literature for studies reporting objectively measured weight-bearing activity in people with diabetes-related foot disease. We calculated daily step counts' means (over studies) and weighted means (over participants). International Working Group on the Diabetic Foot (IWGDF) risk strata, different climates, and activity indoors versus outdoors were compared.

RESULTS

From 1247 publications, 27 were included. Mean steps/day in people with IWGDF risk 1/2: 6125 (12 studies; 345 participants; weighted mean: 5384). In IWGDF risk 3: 6167 (8 studies; 291 participants; weighted mean: 6239). In those with a foot ulcer: 4248 (6 studies; 186 participants; weighted mean: 4484). People living in temperate oceanic climates are more active compared to those in hotter or more humid climates (mean steps/day for no ulcer: 7712 vs. 5224 [18 studies]; for ulcer: 6819 vs. 2945 [6 studies]). People are more active indoors than outdoors (mean 4047 vs. 2514 [3 studies]).

CONCLUSION

Levels of weight-bearing physical activity are similar between people with diabetes at various risk levels for foot ulceration but lower for those with a foot ulcer. Weight-bearing activity differs depending on the climatological environment and is higher indoors than outdoors. These findings provide reference for intervention studies or for clinicians aiming to provide mobility advice in this population.

Aerobic exercise-induced circulating extracellular vesicle combined decellularized dermal matrix hydrogel facilitates diabetic wound healing by promoting angiogenesis

Background: Insufficient blood supply results in unsatisfactory wound healing, especially for challenging wound repair such as diabetic wound defects. Regular exercise training brings a lot of benefits to cardiovascular fitness and metabolic health including attenuation of T2DM progression. Circulating extracellular vesicles (EVs) are postulated to carry a variety of signals involved in tissue crosstalk by their modified cargoes, representing novel mechanisms for the effects of exercise. Prominently, both acute and chronic aerobic exercise training can promote the release of exercise-induced cytokines and enhance the angiogenic function of circulating angiogenic cell–derived EVs.

Methods: We investigated the possible angiogenesis potential of aerobic exercise-induced circulating EVs (EXE-EVs) on diabetic wound healing. Circulating EVs were isolated from the plasma of rats subjected to 4 weeks of moderate aerobic exercise or sedentariness 24 h after the last training session. The therapeutic effect of circulating EVs was evaluated in vitro by proliferation, migration, and tube formation assays of human umbilical vein endothelial cells (HUVECs), as well as in vivo by quantification of angiogenesis and cutaneous wound healing in diabetic rats.

Results: The number of circulating EVs did not change significantly in exercised rats 24 h post-exercise in comparison with the sedentary rats. Nevertheless, EXE-EVs showed remarkable pro-angiogenic effect by augmenting proliferation, migration, and tube formation of HUVECs. Furthermore, the findings of animal experiments revealed that the EXE-EVs delivered by decellularized dermal matrix hydrogel (DDMH) could significantly promote the repair of skin defects through stimulating the regeneration of vascularized skin.

Discussion: The present study is the first attempt to demonstrate that aerobic exercise-induced circulating EVs could be utilized as a cell-free therapy to activate angiogenesis and promote diabetic wound healing. Our findings suggest that EXE-EVs may stand for a potential strategy for diabetic soft tissue wound repair.

Australian guideline on prevention of foot ulceration: part of the 2021 Australian evidence-based guidelines for diabetes-related foot disease

BACKGROUND

There are no current Australian guidelines on the prevention of diabetes-related foot ulceration (DFU). A national expert panel aimed to systematically identify and adapt suitable international guidelines to the Australian context to create new Australian evidence-based guidelines on prevention of first-ever and/or recurrent DFU. These guidelines will include for the first-time considerations for rural and remote, and Aboriginal and Torres Strait Islander peoples.

METHODS

The National Health and Medical Research Council procedures were followed to adapt suitable international guidelines on DFU prevention to the Australian health context. This included a search of public databases after which the International Working Group on the Diabetic Foot (IWGDF) prevention guideline was deemed the most appropriate for adaptation. The 16 IWGDF prevention recommendations were assessed using the ADAPTE and GRADE systems to decide if they should be adopted, adapted or excluded for the new Australian guideline. The quality of evidence and strength of recommendation ratings were re-evaluated with reference to the Australian context. This guideline underwent public consultation, further revision, and approval by national peak bodies.

RESULTS

Of the 16 original IWGDF prevention recommendations, nine were adopted, six were adapted and one was excluded. It is recommended that all people at increased risk of DFU are assessed at intervals corresponding to the IWGDF risk ratings. For those at increased risk, structured education about appropriate foot protection, inspection, footwear, weight-bearing activities, and foot self-care is recommended. Prescription of orthotic interventions and/or medical grade footwear, providing integrated foot care, and self-monitoring of foot skin temperatures (contingent on validated, user-friendly and affordable systems becoming available in Australia) may also assist in preventing DFU. If the above recommended non-surgical treatment fails, the use of various surgical interventions for the prevention of DFU can be considered.

CONCLUSIONS

This new Australian evidence-based guideline on prevention of DFU, endorsed by 10 national peak bodies, provides specific recommendations for relevant health professionals and consumers in the Australian context to prevent DFU. Following these recommendations should achieve better DFU prevention outcomes in Australia.

Australian guideline on offloading treatment for foot ulcers: part of the 2021 Australian evidence-based guidelines for diabetes-related foot disease

BACKGROUND

Pressure offloading treatment is critical for healing diabetes-related foot ulcers (DFU). Yet the 2011 Australian DFU guidelines regarding offloading treatment are outdated. A national expert panel aimed to develop a new Australian guideline on offloading treatment for people with DFU by adapting international guidelines that have been assessed as suitable to adapt to the Australian context.

METHODS

National Health and Medical Research Council procedures were used to adapt suitable International Working Group on the Diabetic Foot (IWGDF) guidelines to the Australian context. We systematically screened, assessed and judged all IWGDF offloading recommendations using best practice ADAPTE and GRADE frameworks to decide which recommendations should be adopted, adapted or excluded in the Australian context. For each recommendation, we re-evaluated the wording, quality of evidence, strength of recommendation, and provided rationale, justifications and implementation considerations, including for geographically remote and Aboriginal and Torres Strait Islander peoples. This guideline, along with five accompanying Australian DFU guidelines, underwent public consultation, further revision and approval by ten national peak bodies (professional organisations).

RESULTS

Of the 13 original IWGDF offloading treatment recommendations, we adopted four and adapted nine. The main reasons for adapting the IWGDF recommendations included differences in quality of evidence ratings and clarification of the intervention(s) and control treatment(s) in the recommendations for the Australian context. For Australians with plantar DFU, we recommend a step-down offloading treatment approach based on their contraindications and tolerance. We strongly recommend non-removable knee-high offloading devices as first-line treatment, removable knee-high offloading devices as second-line, removable ankle-high offloading devices third-line, and medical grade footwear as last-line. We recommend considering using felted foam in combination with the chosen offloading device or footwear to further reduce plantar pressure. If offloading device options fail to heal a person with plantar DFU, we recommend considering various surgical offloading procedures. For people with non-plantar DFU, depending on the type and location of the DFU, we recommend using a removable offloading device, felted foam, toe spacers or orthoses, or medical grade footwear. The six new guidelines and the full protocol can be found at: https://diabetesfeetaustralia.org/new-guidelines/ .

CONCLUSIONS

We have developed a new Australian evidence-based guideline on offloading treatment for people with DFU that has been endorsed by ten key national peak bodies. Health professionals implementing these offloading recommendations in Australia should produce better DFU healing outcomes for their patients, communities, and country.

Multiple factors predict longer and shorter time-to-ulcer-free in people with diabetes-related foot ulcers: Survival analyses of a large prospective cohort followed-up for 24-months

AIMS

To investigate factors independently associated with time-to-(being)-ulcer-free, time-varying effects and predict adjusted ulcer-free probabilities, in a large prospective cohort with diabetes-related foot ulcers (DFU) followed-up for 24 months.

METHODS

Patients presenting with DFU(s) to 65 Diabetic Foot Services across Queensland, Australia, between July-2011 and December-2017 were included. Demographic, comorbidity, limb, ulcer, and treatment factors were captured at presentation. Patients were followed-up until ulcer-free (all DFU(s) healed), amputation, death or two years. Factors associated with time-to-ulcer-free were investigated using both Cox proportional hazards and flexible parametric survival models to explore time-varying effects and plot predicted adjusted ulcer-free probability graphs.

RESULTS

Of 4,709 included patients (median age 63 years, 69.5% male), median time-to-ulcer-free was 112 days (IQR:40->730), with 68.4% ulcer-free within two years. Factors independently associated with longer time-to-ulcer-free were each year of age younger than 60 years, living in a regional or remote area, smoking, neuropathy, peripheral artery disease (PAD), ulcer size >1 cm², deep ulcer and mild infection (all p < 0.05). Time-varying effects were found for PAD and ulcer size limiting their association to six months only. Shorter time-to-ulcer-free was associated with recent DFU treatment by a podiatrist and receiving knee-high offloading treatment (both p < 0.05). Predicted adjusted ulcer-free probability graphs reported largest differences in time-to-ulcer-free over 24-months for geographical remoteness and PAD factors.

CONCLUSIONS

Multiple factors predicted longer and shorter time-to-ulcer-free in people presenting with DFUs. Considering these factors, their time-varying effects and adjusted ulcer-free probability graphs, should aid the prediction of the likely time-to-(being)-ulcer-free for DFU patients.

Custom-made footwear designed for indoor use increases short-term and long-term adherence in people with diabetes at high ulcer risk

INTRODUCTION

To explore changes in footwear adherence following provision of custom-made indoor footwear in people with diabetes at high risk for plantar foot ulceration and in possession of regular custom-made footwear.

RESEARCH DESIGN AND METHODS

Adherence indoors and outdoors was assessed objectively as percentage of steps custom-made footwear was worn, at baseline (in regular custom-made footwear), and at 1 and 12 months after providing custom-made indoor footwear (in both indoor and regular footwear). Primary group: participants with low (<80%) baseline indoor adherence; secondary group: participants with high (≥80%) baseline indoor adherence. Peak plantar pressures of the indoor footwear were compared with the regular custom-made footwear. Footwear usability was evaluated at 3 months via a questionnaire. At 12 months, ulcer recurrence was assessed through participant/prescriber reporting.

RESULTS

Of 31 participants, 23 had low baseline indoor adherence (<80%). Overall adherence in this group increased statistically significant from median 65% (IQR: 56%-72%) at baseline to 77% (60%-89%) at 1 month (p=0.002) and 87% (60%-93%) at 12 months (p<0.001). This was due to a significant increase in adherence indoors: baseline: 48% (21%-63%); 1 month: 71% (50%-83%) (p=0.001); and 12 months: 77% (40%-91%) (p<0.001). Mean peak plantar pressures were comparable between the indoor and regular custom-made footwear. Participants were positive about usability. One-year ulcer recurrence rate was 26%.

CONCLUSIONS

Footwear adherence increased in the short-term and long-term after provision of custom-made indoor footwear in people at high risk of diabetic foot ulceration with low baseline adherence, because they actively wore their newly provided indoor footwear inside their house. Footwear adherence may be helped by using both regular and indoor custom-made footwear in clinical practice; the effect on ulcer recurrence should be investigated in future trials.

Factors associated with adherence to using removable cast walker treatment among patients with diabetes-related foot ulcers

INTRODUCTION

Adherence to using knee-high offloading treatment is critical for healing diabetes-related foot ulcers (DFUs). However, few studies have investigated patients' adherence to using knee-high offloading treatment. We aimed to investigate the levels and factors associated with adherence to using knee-high removable cast walker (RCW) treatment among patients with DFUs.

RESEARCH DESIGN AND METHODS

In this multicenter cross-sectional study, we investigated adherence to using knee-high RCWs in 57 participants with DFUs. All participants were clinically examined for multiple sociodemographic, physiological, and psychosocial factors. Each participant's adherence level to using RCWs was then objectively measured using dual activity monitors (attached to the wrist and RCW) over a 1-week period. Multiple linear regression was undertaken to determine those factors independently associated with adherence levels.

RESULTS

The mean adherence level to using RCWs was 33.6% (SD 16.5) of weight-bearing activity. Factors independently associated with lower adherence levels were being male, longer diabetes duration, not having peripheral artery disease (PAD), and having higher perceived RCW heaviness (p≤0.05). No associations were found with psychosocial factors.

CONCLUSIONS

Patients with DFUs adhered to using their RCWs on average for only a third of their prescribed weight-bearing treatment duration. Factors linked to lower RCW adherence levels were being male, longer diabetes duration, not having PAD, and perceived heavier RCWs. These findings highlight the importance of using gold standard non-removable knee-high offloading device treatment. Furthermore, these findings suggest, when gold standard devices are containdicated, that these factors be considered when prescribing the second choice RCW offloading treatment to optimise adherence. Regardless, further longitudinal studies are needed to confirm these factors.

Plantar shear stress in the diabetic foot: A systematic review and meta-analysis

AIMS

Diabetic foot ulceration (DFU) is a multifactorial process involving undetected, repetitive trauma resulting in inflammation and tissue breakdown. Shear stress forms a major part of plantar load, the aim of this review is to determine whether elevated shear stress results in ulceration.

METHODS

A systematic review of the Ovid Medline, EMBASE, CINAHL and Cochrane library databases was performed. Studies involving patients with diabetes who underwent plantar shear stress assessment were included. The primary outcome was plantar shear stress in patients with diabetes who had a current/previous DFU compared with those with no prior ulceration. Meta-analysis was performed comparing shear stress between those with a current or previous DFU and those without, and those with diabetes and healthy controls.

RESULTS

The search strategy identified 1461 potentially relevant articles, 16 studies met the inclusion criteria, involving a total of 597 patients. Comparing shear stress between the current/previous DFU group and those without: Standardised mean difference (SMD) 0.62 (95% CI -0.01 to 1.25), in favour of greater shear stress within the DFU group, p = 0.05. Comparing shear stress between people with diabetes and healthy controls: 0.36 (95% CI -0.31 to 1.03), in favour of greater shear stress within the diabetes group, p = 0.29.

CONCLUSION

This review suggests that that patients with diabetes and a history of ulceration exhibit greater shear stress than their ulcer-free counterparts. This strengthens the premise that development of systems to measure shear stress may be helpful in DFU prediction and prevention.

Effectiveness of Lower-Extremity Electrical Stimulation to Improve Skin Perfusion

BACKGROUND

Although numerous studies suggest the benefit of electrical stimulation (E-Stim) therapy to accelerate wound healing, the underlying mechanism of action is still debated. In this pilot study, we examined the potential effectiveness of lower-extremity E-Stim therapy to improve tissue perfusion in patients with diabetic foot ulcers.

METHODS

Thirty-eight patients with diabetic foot ulcers underwent 60 min of active E-Stim therapy on acupuncture points above the level of the ankle joint using a bioelectric stimulation technology platform. Perfusion changes in response to E-Stim were assessed by measuring skin perfusion pressure (SPP) at baseline and during 30 and 60 min of therapy; retention was assessed 10 min after therapy. Tissue oxygen saturation (SatO2) was measured using a noninvasive near-infrared camera.

RESULTS

Skin perfusion pressure increased in response to E-Stim therapy (P = .02), with maximum improvement observed at 60 min (11%; P = .007) compared with baseline; SPP reduced 10 min after therapy but remained higher than baseline (9%; P = .1). Magnitude of improvement at 60 min was negatively correlated with baseline SPP values (r = -0.45; P = .01), suggesting that those with lower perfusion could benefit more from E-Stim therapy. Similar trends were observed for SatO2, with statistically significant improvement for a subsample (n = 16) with moderate-to-severe peripheral artery disease.

CONCLUSIONS

This study provides early results on the feasibility and effectiveness of E-Stim therapy to improve skin perfusion and SatO2. The magnitude of benefit is higher in those with poorer skin perfusion. Also, the effects of E-Stim could be washed out after stopping therapy, and regular daily application might be required for effective benefit in wound healing.

Establishing the national top 10 priority research questions to improve diabetes-related foot health and disease: a Delphi study of Australian stakeholders

INTRODUCTION

Diabetes-related foot disease is a large cause of the global disease burden yet receives very little research funding to address this large burden. To help address this gap, it is recommended to first identify the consensus priority research questions of relevant stakeholders, yet this has not been performed for diabetes-related foot disease. The aim of this study was to determine the national top 10 priority research questions for diabetes-related foot health and disease from relevant Australian stakeholders.

RESEARCH DESIGN AND METHODS

A modified three-round Delphi online survey design was used to seek opinions from relevant Australian stakeholders including those with diabetes or diabetes-related foot disease or their carers (consumers), health professionals, researchers and industry. Participants were recruited via multiple public invitations and invited to propose three research questions of most importance to them (Round 1), prioritize their 10 most important questions from all proposed questions (Round 2), and then rank questions in order of importance (Round 3).

RESULTS

After Round 1, a total of 226 unique questions were proposed by 210 participants (including 121 health professionals and 72 consumers). Of those participants, 95 completed Round 2 and 69 completed Round 3. The top 10 priority research questions covered a range of topics, including health economics, peripheral neuropathy, education, infection, technology, exercise, and nutrition. Consumers prioritized peripheral neuropathy and prevention-related questions. Health professionals prioritized management-related questions including Australia's First Peoples foot health, health economics and infection questions.

CONCLUSIONS

These priority research questions should guide future national research agendas, funding and projects to improve diabetes-related foot disease burdens in Australia and globally. Future research should focus on consumer priority research questions to improve the burden of diabetes-related foot disease on patients and nations. Further research should also investigate reasons for different priorities between consumers and health professionals.

Knee-High Devices Are Gold in Closing the Foot Ulcer Gap: A Review of Offloading Treatments to Heal Diabetic Foot Ulcers

Diabetic foot ulcers (DFU) are a leading cause of the global disease burden. Most DFUs are caused, and prolonged, by high plantar tissue stress under the insensate foot of a person with peripheral neuropathy. Multiple different offloading treatments have been used to try to reduce high plantar tissue stress and heal DFUs, including bedrest, casting, offloading devices, footwear, and surgical procedures. The best offloading treatments are those that balance the benefits of maximizing reductions in high plantar tissue stress, whilst reducing the risks of poor satisfaction, high costs and potential adverse events outcomes. This review aimed to summarize the best available evidence on the effects of offloading treatments to heal people with DFUs, plus review their use in clinical practice, the common barriers and solutions to using these treatments, and discuss promising emerging solutions that may improve offloading treatments in future. Findings demonstrate that knee-high offloading devices, non-removable or removable knee-high devices worn for all weight-bearing activities, are the gold standard offloading treatments to heal most patients with DFU, as they are much more effective, and typically safer, quicker, and cheaper to use compared with other offloading treatments. The effectiveness of offloading treatments also seems to increase when increased offloading mechanical features are incorporated within treatments, including customized insoles, rocker-bottom soles, controlled ankle motion, and higher cast walls. However, in clinical practice these gold standard knee-high offloading devices have low rates of prescription by clinicians and low rates of acceptance or adherence by patients. The common barriers resulting in this low use seem to surround historical misperceptions that are mostly dispelled by contemporary evidence. Further, research is now urgently required to close the implementation gap between the high-quality of supporting evidence and the low use of knee-high devices in clinical practice to reduce the high global disease burden of DFU in future.

Dosing Activity and Return to Preulcer Function in Diabetes-Related Foot Ulcer Remission

Diabetes-related foot ulcers are a leading cause of global morbidity, mortality, and health-care costs. People with a history of foot ulcers have a diminished quality of life attributed to limited walking and mobility. One of the largest concerns is ulceration recurrence. Approximately 40% of patients with ulcerations will have a recurrent ulcer in the year after healing, and most occur in the first 3 months after wound healing. Hence, this period after ulceration is called "remission" due to this risk of reulceration. Promoting and fostering mobility is an integral part of everyday life and is important for maintaining good physical health and health-related quality of life for all people living with diabetes. In this short perspective, we provide recommendations on how to safely increase walking activity and facilitate appropriate off-loading and monitoring in people with a recently healed foot ulcer, foot reconstruction, or partial foot amputation. Interventions include monitored activity training, dosed out in steadily increasing increments and coupled with daily skin temperature monitoring, which can identify dangerous "hotspots" prone to recurrence. By understanding areas at risk, patients are empowered to maximize ulcer-free days and to enable an improved quality of life. This perspective outlines a unified strategy to treat patients in the remission period after ulceration and aims to provide clinicians with appropriate patient recommendations based on best available evidence and expert opinion to educate their patients to ensure a safe transition to footwear and return to activity.

The effects of different accumulated pressure-time integral stimuli on plantar blood flow in people with diabetes mellitus

Background

Exercise, especially weight-bearing exercise (e.g. walking), may affect plantar tissue viability due to prolonged repetitive high vertical and high shear pressure stimulus on the plantar tissue, and further induce development of diabetic foot ulcers (DFUs). This study aimed to investigate the effects of different accumulated pressure-time integral (APTI) stimuli induced by walking on plantar skin blood flow (SBF) responses in people with diabetes mellitus (DM).

Methods

A repeated measures design was used in this study. Two walking protocols (low APTI (73,000 kPa·s) and high APTI (73,000 × 1.5 kPa·s)) were randomly assigned to ten people with DM and twenty people without DM. The ratio of SBF measured by laser Doppler flowmetry after walking to that before (normalized SBF) was used to express the SBF responses.

Results

After low APTI, plantar SBF of people with DM showed a similar response to people without DM (P = 0.91). However, after high APTI, people with DM had a significantly lower plantar SBF compared to people without DM (P < 0.05). In people with DM, plantar SBF in the first 2 min after both APTI stimuli significantly decreased compared to plantar SBF before walking (P < 0.05).

Conclusions

People with DM had a normal SBF response after low APTI walking but had an impaired SBF response after high APTI walking, which suggests that they should avoid weight-bearing physical activity with intensity more than 73,000 kPa·s and should rest for more than 2 min after weight-bearing physical activity to allow a full vasodilatory response to reduce risk of DFUs.

Podiatrist-Delivered Health Coaching to Facilitate the Use of a Smart Insole to Support Foot Health Monitoring in People with Diabetes-Related Peripheral Neuropathy

This trial evaluated the feasibility of podiatrist-led health coaching (HC) to facilitate smart-insole adoption and foot monitoring in adults with diabetes-related neuropathy. Adults aged 69.9 ± 5.6 years with diabetes for 13.7 ± 10.3 years participated in this 4-week explanatory sequential mixed-methods intervention. An HC training package was delivered to podiatrists, who used HC to issue a smart insole to support foot monitoring. Insole usage data monitored adoption. Changes in participant understanding of neuropathy, foot care behaviours, and intention to adopt the smart insole were measured. Focus group and in-depth interviews explored quantitative data. Initial HC appointments took a mean of 43.8 ± 8.8 min. HC fidelity was strong for empathy/rapport and knowledge provision but weak for assessing motivational elements. Mean smart-insole wear was 12.53 ± 3.46 h/day with 71.2 ± 13.9% alerts not effectively off-loaded, with no significant effect for time on usage F(3,6) = 1.194 (p = 0.389) or alert responses F(3,6) = 0.272 (p = 0.843). Improvements in post-trial questionnaire mean scores and focus group responses indicate podiatrist-led HC improved participants’ understanding of neuropathy and implementation of footcare practices. Podiatrist-led HC is feasible, supporting smart-insole adoption and foot monitoring as evidenced by wear time, and improvements in self-reported footcare practices. However, podiatrists require additional feedback to better consolidate some unfamiliar health coaching skills. ACTRN12618002053202.