Long-term prognosis for diabetic patients with foot ulcers

A Multi-Faceted Digital Health Solution for Monitoring and Managing Diabetic Foot Ulcer Risk: A Case Series

INTRODUCTION

Diabetic foot ulcers (DFU) are a devastating complication of diabetes. There are numerous challenges with preventing diabetic foot complications and barriers to achieving the care processes suggested in established foot care guidelines. Multi-faceted digital health solutions, which combine multimodal sensing, patient-facing biofeedback, and remote patient monitoring (RPM), show promise in improving our ability to understand, prevent, and manage DFUs.

METHODS

Patients with a history of diabetic plantar foot ulcers were enrolled in a prospective cohort study and equipped with custom sensory insoles to track plantar pressure, plantar temperature, step count, and adherence data. Sensory insole data enabled patient-facing biofeedback to cue active plantar offloading in response to sustained high plantar pressures, and RPM assessments in response to data trends of concern in plantar pressure, plantar temperature, or sensory insole adherence. Three non-consecutive case participants that ultimately presented with pre-ulcerative lesions (a callus and/or erythematous area on the plantar surface of the foot) during the study were selected for this case series.

RESULTS

Across three illustrative patients, continuous plantar pressure monitoring demonstrated promise for empowering both the patient and provider with information for data-driven management of pressure offloading treatments.

CONCLUSION

Multi-faceted digital health solutions can naturally enable and reinforce the integrative foot care guidelines. Multi-modal sensing across multiple physiologic domains supports the monitoring of foot health at various stages along the DFU pathogenesis pathway. Furthermore, digital health solutions equipped with remote patient monitoring unlock new opportunities for personalizing treatments, providing periodic self-care reinforcement, and encouraging patient engagement-key tools for improving patient adherence to their diabetic foot care plan.

The Appropriateness of Footwear in Diabetic Patients Observed during a Podiatric Examination: A Prospective Observational Study

Background: Adequate compliance with wearing therapeutic footwear (TF) to prevent diabetic foot ulcers is known to be low. The primary aim of this study was to identify population awareness about the ulceration and/or recurrence risk according to footwear choice. The secondary aim was to evaluate the compliance level in footwear choice based on a patient's own risk. Methods: Forty podiatrists participated from 1 September 2017 to 31 August 2018, providing six-section forms which included personal data, risk classification, footwear characteristics and a knowledge questionnaire. Results: This study included 1507 patients. Those with active ulcers were excluded. A total of 43% of patients belonged to risk class 0, 19% to risk class 1, 19% to risk class 2 and 19% to risk class 3. A total of 58% had foot deformities. Conclusions: Nearly half of patients with a high risk of ulceration had knowledge of their own risk but the majority of them did not follow the recommendations. Only a small percentage (36%) of risk class 3 patients wore footwear suitable for their risk class. There was poor consideration of footwear choice among patients. We highlight critical issues in patient education and compliance with wearing footwear appropriate to their risk class.

Diabetic foot ulcers, their characteristics, and trends in survival: Real world outcomes at a tertiary care facility in India

AIMS

Characteristics of diabetes-related foot ulcers (DFU), association with recurrence and amputation are poorly described in the Asian Indian population.

METHODS

A prospectively maintained database was reviewed to characterize DFU and its association with amputation and recurrence.

RESULTS

Of 200 patients, 63.5 % were male, the median age was 62 years (Min-Max:40-86), and median BMI was 27.90 kg/m2 (Min-Max:18.5-42.7). Median duration of Diabetes mellitus was 15 years (Min-Max:2-43). Complete healing occurred at a median of three months (Min-Max:0.23-37.62). Amputation for the current ulcer was required in 43.4 % of individuals. Ulcer recurrence was documented in 42.4 % instances, 66.1 % evolving on the ipsilateral side. Previous amputation was associated with the risk of subsequent amputation (Adjusted OR-3.08,p-0.047). Median time to ulcer recurrence was 4.23 years among those with amputation, in contrast to 9.61 years in those with healing. Cardiovascular death was the commonest cause of mortality, followed by sepsis. At a median follow up of 6.08 years, mortality at 1,3,5 and 10 years was 2.5 %,2.5 %,8.2 % and 30.9 % respectively among those who underwent amputation versus 0 %,0 %,10.1 % and 24.5 % respectively for those who achieved healing.

CONCLUSIONS

Patients with DFU in India incur amputations at rates higher than conventionally described. With previous amputation, subsequent amputation risk triples. Ten-year mortality is 25%-30 %. Underestimates of the burden of recurrence and mortality are consequential of limited follow-up.

Use of hypothermically stored amniotic membrane on diabetic foot ulcers: a multicentre retrospective case series

OBJECTIVE

The aim of this retrospective case series was to report on the outcomes of diabetic foot ulcers (DFUs) managed with hypothermically stored amniotic membrane (HSAM).

METHOD

Deidentified case data of patients who received HSAM were obtained from wound care sites across the US. Data were collected, beginning at the first patient visit to the wound care site (first presentation), at the visit in which the first HSAM application occurred (baseline), and at each subsequent visit over 12 weeks of treatment (follow-up). All patients received standard of care (SoC) between first presentation and baseline.

RESULTS

Of the 50 patients in the study, 68% were male. Mean age of the entire cohort was 66.7 years. Of the DFUs, 88% were present for <6 months at first presentation. Mean wound area was 3.5cm2, and mean percentage area reduction was -68.3% from first presentation to baseline. The mean number of HSAM applications was 5.5, and mean number of days between applications was 7.5. A >60% area reduction was attained in 96.0% of DFUs, and 78% attained complete wound closure (CWC) by week 12. The median time to CWC was 55 days.

CONCLUSION

The results of this retrospective case series suggest positive outcomes for DFUs managed with HSAM. A reduction in time to CWC may lead to lesser financial burden and improved quality of life for DFU patients.

DECLARATION OF INTEREST

The authors have no conflicts of interest.

A 2-Stage Approach in Managing Diabetic Forefoot Ulcers

BACKGROUND

Forefoot plantar ulcers in patients with diabetic neuropathy are considered to be primarily the result of increased shear forces applied over prominent plantar bony prominences. The purpose of this article is to describe a 2-stage treatment pathway utilizing an outpatient percutaneous tendon-Achilles lengthening (TAL) as the first stage procedure and subsequent proximal metatarsal osteotomy (MTO) as a second stage procedure for a persistent or recurrent ulcer.

METHODS

A consecutive 112 patients (146 feet), who presented to our Multidisciplinary Diabetic Foot Team clinics since February 2019 with plantar nonischemic forefoot ulcers were included in this study. Excluding the patients who died or were lost to follow-up, 96 feet were followed for a minimum 12 months (range 12-36 months). After TAL, patients were encouraged to walk in a walking cast for 6 weeks and were followed for a minimum 12 months. Patients with persistent or recurrent ulcers were investigated with magnetic resonance imaging scan, and based on intramedullary osteomyelitis and septic destruction of distal metatarsal, we describe a second-stage MTO with the 3 most common clinical presentations.

RESULTS

Of 96 feet, none had infection or wound-related problems following TAL. Complete transection of the tendon was noted in 4 patients (4%) and heel callosity in 1 patient. In 92 feet (96%), the ulcers healed within 10 weeks (±4 weeks) after TAL but, in 12 feet (10%), the ulcer failed to heal or recurred. At a minimum 12 months after the second-stage MTO, none in this subgroup had recurrence of ulcer or a transfer lesion.

CONCLUSION

TAL followed with a walking cast as an outpatient procedure was effective in healing forefoot ulcers in 96% of feet. Comparable to the widely practiced hand surgery Wide Awake Local Anesthesia No Tourniquet (WALANT) procedure, our approach involved active control of the degree of ankle dorsiflexion by the patient, and the procedure was proven to be safe and well tolerated. When the second-stage MTO was required to offload the forefoot, in our small cohort, patients had ulcer-free outcome for a minimum 12 months.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Electrostatically assembled wound dressings deliver pro-angiogenic anti-miRs preferentially to endothelial cells

Chronic non-healing wounds occur frequently in individuals affected by diabetes, yet standard-of-care treatment leaves many patients inadequately treated or with recurring wounds. MicroRNA (miR) expression is dysregulated in diabetic wounds and drives an anti-angiogenic phenotype, but miRs can be inhibited with short, chemically-modified RNA oligonucleotides (anti-miRs). Clinical translation of anti-miRs is hindered by delivery challenges such as rapid clearance and uptake by off-target cells, requiring repeated injections, excessively large doses, and bolus dosing mismatched to the dynamics of the wound healing process. To address these limitations, we engineered electrostatically assembled wound dressings that locally release anti-miR-92a, as miR-92a is implicated in angiogenesis and wound repair. In vitro, anti-miR-92a released from these dressings was taken up by cells and inhibited its target. An in vivo cellular biodistribution study in murine diabetic wounds revealed that endothelial cells, which play a critical role in angiogenesis, exhibit higher uptake of anti-miR eluted from coated dressings than other cell types involved in the wound healing process. In a proof-of-concept efficacy study in the same wound model, anti-miR targeting anti-angiogenic miR-92a de-repressed target genes, increased gross wound closure, and induced a sex-dependent increase in vascularization. Overall, this proof-of-concept study demonstrates a facile, translational materials approach for modulating gene expression in ulcer endothelial cells to promote angiogenesis and wound healing. Furthermore, we highlight the importance of probing cellular interactions between the drug delivery system and the target cells to drive therapeutic efficacy.

Definition and evaluation of a finite element model of the human heel for diabetic foot ulcer prevention under shearing loads

Diabetic foot ulcers are triggered by mechanical loadings applied to the surface of the plantar skin. Strain is considered to play a crucial role in relation to ulcer etiology and can be assessed by Finite Element (FE) modeling. A difficulty in the generation of these models is the choice of the soft tissue material properties. In the literature, many studies attempt to model the behavior of the heel soft tissues by implementing constitutive laws that can differ significantly in terms of mechanical response. Moreover, current FE models lack of proper evaluation techniques that could estimate their ability to simulate realistic strains. In this article, we propose and evaluate a FE model of the human heel for diabetic foot ulcer prevention. Soft tissue constitutive laws are defined through the fitting of experimental stretch-stress curves published in the literature. The model is then evaluated through Digital Volume Correlation (DVC) based on non-rigid 3D Magnetic Resonance Image Registration. The results from FE analysis and DVC show similar strain locations in the fat pad and strain intensities according to the type of applied loads. For additional comparisons, different sets of constitutive models published in the literature are applied into the proposed FE mesh and simulated with the same boundary conditions. In this case, the results in terms of strains show great diversity in locations and intensities, suggesting that more research should be developed to gain insight into the mechanical properties of these tissues.

Sex differences in diabetic foot ulcer severity and outcome in Belgium

BACKGROUND

Sex differences are increasingly recognized to play an important role in the epidemiology, treatment and outcomes of many diseases. This study aims to describe differences between sexes in patient characteristics, ulcer severity and outcome after 6 months in individuals with a diabetic foot ulcer (DFU).

METHODS

A total of 1,771 patients with moderate to severe DFU participated in a national prospective, multicenter cohort study. Data were collected on demographics, medical history, current DFU and outcome. For data analysis, a Generalized Estimating Equation model and an adjusted Cox proportional hazards regression were used.

RESULTS

The vast majority of patients included were male (72%). Ulcers in men were deeper, more frequently displaying probe to bone, and more frequently deeply infected. Twice as many men presented with systemic infection as women. Men demonstrated a higher prevalence of previous lower limb revascularization, while women presented more frequently with renal insufficiency. Smoking was more common in men than in women. No differences in presentation delay were observed. In the Cox regression analysis, women had a 26% higher chance of healing without major amputation as a first event (hazard ratio 1.258 (95% confidence interval 1.048-1.509)).

CONCLUSIONS

Men presented with more severe DFU than women, although no increase in presentation delay was observed. Moreover, female sex was significantly associated with a higher probability of ulcer healing as a first event. Among many possible contributing factors, a worse vascular state associated with a higher rate of (previous) smoking in men stands out.

A vicious cycle: employment challenges associated with diabetes foot ulcers in an economically marginalized Southwest US sample

Aim

To describe patients' reported employment challenges associated with diabetic foot ulcers (DFUs).

Methods

Fifteen patients from under-resourced communities in Southern Arizona, with a history of DFUs and/or amputations, were recruited from a tertiary referral center from June 2020 to February 2021. Participants consented to an audio-recorded semi-structured phone interview. Interviews were transcribed and thematically analyzed using the Dedoose data analysis platform.

Results

Participants shared a common theme around the cyclic challenges of DFU prevention/management and employment. Those employed in manual labor-intensive jobs or jobs requiring them to be on their feet for long durations of time believed working conditions contributed to the development of their DFUs. Patients reported work incapacity due to declines in mobility and the need to offload for DFU management. Many expressed frustration and emotional distress related to these challenges noting that DFUs resulted in lower remuneration as medical expenses increased. Consequently, loss of income and/or medical insurance often hindered participants' ability to manage DFUs and subsequent complications.

Conclusion

These data illuminate the vicious cycle of DFU and employment challenges that must be addressed through patient-centered prevention strategies. Healthcare providers should consider a person's contextual factors such as employment type to tailor treatment approaches. Employers should establish inclusive policies that support patients with DFUs returning to work through flexible working hours and adapted work tasks as needed. Policymakers can also mitigate employment challenges by implementing social programs that provide resources for employees who are unable to return to work in their former capacity.

The importance of inflammation control for the treatment of chronic diabetic wounds

Diabetic chronic wounds cause massive levels of patient suffering and economic problems worldwide. The state of chronic inflammation arises in response to a complex combination of diabetes mellitus-related pathophysiologies. Advanced treatment options are available; however, many wounds still fail to heal, exacerbating morbidity and mortality. This review describes the chronic inflammation pathophysiologies in diabetic ulcers and treatment options that may help address this dysfunction either directly or indirectly. We suggest that treatments to reduce inflammation within these complex wounds may help trigger healing.

Implementation of a novel mHealth application for the management of people with diabetes and recently healed foot ulceration: A feasibility study

Background

Diabetic foot ulcers (DFUs) cause significant morbidity and mortality. Faster referral to specialist clinics is associated with a reduced risk of severe DFUs. The INTELLIN^® diabetes management platform is a novel mHealth application for the management of recently healed DFUs and other complications, promoting engagement and expediting self-referral.

Methods

To determine the acceptability, suitability, and usability of the INTELLIN^® platform, time until reulceration, site, ischemia, neuropathy, bacterial infection, and depth (SINBAD) score and incidence of self-referral for recurrence were assessed in patients from the Salford Royal NHS Foundation Trust. Patients and clinic staff also assessed platform usability. A Markov cost-utility model was used for the health economics and outcomes research analysis.

Results

197 patients were assessed for eligibility and 15 entered the full analysis set (FAS). Through Week 52, 8/15 patients experienced recurrence, with a mean SINBAD score of 2.1 and mean duration of 2.6 days. Mean time to recurrence was 273.0 days (95% confidence interval 74.0, 484.0). No patients self-referred. Initial qualitative data showed high platform usability. The INTELLIN^® platform only required a relative reduction in recurrence of 5% versus standard of care (SoC) for an incremental cost effectiveness ratio of £20,000 per quality-adjusted life-year, suggesting potential for significant cost savings upon wider adoption. The barriers to enrollment encountered demonstrate the impact of socioeconomics on mHealth.

Conclusions

These results suggest that the INTELLIN^® platform is required to provide only a small reduction in recurrence compared to SoC to be a cost-effective strategy for prevention of recurrent DFUs.

Internal Offloading or Surgical Offloading Adjuvant Techniques in the Reconstruction of Diabetic Plantar First Metatarsal Head Ulcer For Lasting Results

Introduction  Management of diabetic foot ulcers (DFUs) is subverted by recurrences. The main cause for the recurrence of DFUs is the failure to recognize and address all the faulty biomechanics precipitating and perpetuating the ulcer. So, we have devised a protocol for treating the diabetic plantar first metatarsal head ulcer (DPFMHUs) incorporating structured internal offloading procedures in conjunction with reconstruction. Aim  The aim of this study was to evaluate our protocol in the management of DPFMHUs. Materials and Methods  Fifty-one patients (31 males and 20 females) with DPFMHUs were managed with our protocol in this prospective cohort study conducted from March 2015 to March 2020. All the faulty biomechanics were addressed by tailored internal offloading procedure as per the protocol. Results  All patients were followed up for an average period of 23.7 months. Early complications were in the form of wound infection (3 patients, 5.9%) and seroma/hematoma (2 patients, 3.9%). Late complication in the form of recurrence was seen only in one patient (1.9%); rest of the patients had no recurrence (98%). Transfer lesions were noted in six patients (11.8%). Conclusion  Our tailored protocol, which addresses all the faulty biomechanics associated with the DPFMHU, may be very helpful in preventing the recurrence and to give lasting results. It is imperative to design a tailored internal/surgical offloading procedure for all deforming forces that are responsible for precipitation and perpetuation of DPFMHUs, in addition to like tissue reconstruction.

Association among Current Smoking, Alcohol Consumption, Regular Exercise, and Lower Extremity Amputation in Patients with Diabetic Foot: Nationwide Population-Based Study

BACKGRUOUND

The present study investigates whether modifiable behavioral factors of current cigarette smoking, heavy alcohol consumption, and regular exercise are associated with risk of lower extremity amputation (LEA) in diabetic patients.

METHODS

A total of 2,644,440 diabetic patients (aged ≥20 years) was analyzed using the database of the Korean National Health Insurance Service. Cox proportional hazard regression was used to assess adjusted hazard ratios (HRs) for the behavioral factors with risk of LEA under adjustment for potential confounders.

RESULTS

The risk of LEA was significantly increased by current cigarette smoking and heavy alcohol consumption (HR, 1.436; 95% confidence interval [CI], 1.367 to 1.508 and HR, 1.082; 95% CI, 1.011 to 1.158) but significantly decreased with regular exercise (HR, 0.745; 95% CI, 0.706 to 0.786) after adjusting for age, sex, smoking, alcohol consumption, exercise, low income, hypertension, dyslipidemia, body mass index, using insulin or oral antidiabetic drugs, and diabetic duration. A synergistically increased risk of LEA was observed with larger number of risky behaviors.

CONCLUSION

Modification of behaviors of current smoking, heavy alcohol intake, and exercise prevents LEA and can improve physical, emotional, and social quality of life in diabetic patients.

Distal Metatarsal Osteotomies for Chronic Plantar Diabetic Foot Ulcers

In more than 30 years of scientific literature (1986-2021), the few published studies on the management of CPDFUs by DMOs showed satisfactory clinical and radiographic outcomes. Although these reports were all case series, their data suggest that DMOs, performed at a different level of the distal metatarsal bones, are an effective surgical treatment option for achieving rapid healing of CPDFUs and preventing their recurrence after balancing the pressures in diabetic forefeet. Hence, DMOs can be a valid alternative treatment method also for CPDFUs with chronic infection, ulcers penetrating deep structures, and even ulcers with osteomyelitis at the metatarsophalangeal level.

Evaluation of novel plantar pressure-based 3-dimensional printed accommodative insoles - A feasibility study

BACKGROUND

Custom insoles are commonly prescribed to patients with diabetes to redistribute plantar pressure and decrease the risk of ulceration. Advances in 3D printing have enabled the creation of 3D-printed personalized metamaterials whose properties are derived not only from the base material but also the lattice microstructures within the metamaterial. Insoles manufactured using personalized metamaterials have both patient-specific geometry and stiffnesses. However, the safety and biomechanical effect of the novel insoles have not yet been tested clinically.

METHODS

Individuals without ulcer, neuropathy, or deformity were recruited for this study. In-shoe walking plantar pressure at baseline visit was taken and sensels with pressure over 200 kPa was used to define offloading region(s). Three pairs of custom insoles (two 3D printed insoles with personalized metamaterials (Hybrid and Full) designed based on foot shape and plantar pressure mapping and one standard-of-care diabetic insole as a comparator). In-shoe plantar pressure measurements during walking were recorded in a standardized research shoe and the three insoles and compared across all four conditions.

FINDINGS

Twelve individuals were included in the final analysis. No adverse events occurred during testing. Maximum peak plantar pressure and the pressure time integral were reduced in the offloading regions in the Hybrid and Full but not in the standard-of-care compared to the research shoe.

INTERPRETATION

This feasibility study confirms our ability to manufacture the 3D printed personalized metamaterials insoles and demonstrates their ability to reduce plantar pressure. We have demonstrated the ability to modify the 3D printed design to offload certain parts of the foot using plantar pressure data and a patient-specific metamaterials in the 3D printed insole design. The advance in 3D printed technology has shown its potential to improve current care.

Prediction of diabetic foot amputation using newly revised DIRECT coding system: Comparison of accuracy with that of five existing classification systems

Diabetes mellitus (DM) causes various complications over time, one such complication is diabetic foot ulcers (DFU), which are challenging to treat and can lead to amputation. Additionally, a system for accurate prediction of amputation has yet to be developed. In total, 131 patients were included in the study after retrospectively collecting data from 2016 to 2020 about DFU. The collected data were used for comparison of the accuracy between five existing classification systems and the newly revised DIRECT coding system, and investigation of risk factors for lower extremity amputation (LEA). The existing five classification systems and DIRECT system can effectively predict LEA. The DIRECT3 system has three elements, C-reactive protein (CRP), ulcer history (UH), and hypertension (HTN) in addition to those of the DIRECT system. It had a high predictive value and accuracy similar to that of Wagner and University of Texas (UT) on depth among the five classification systems. Among the statistically significant risk factors, duration of DM and HTN, haemoglobin (Hb), CRP, and UH showed an association with LEA. The DIRECT coding system is effective for predicting LEA and explaining appropriate treatment methods for DFU, and is widely applicable because of its user accessibility and convenience.

The Use of Point-of-Care Bacterial Autofluorescence Imaging in the Management of Diabetic Foot Ulcers: A Pilot Randomized Controlled Trial

OBJECTIVE

To estimate comparative healing rates and decision-making associated with the use of bacterial autofluorescence imaging in the management of diabetic foot ulcers (DFUs).

RESEARCH DESIGN AND METHODS

This is a single-center (multidisciplinary outpatient clinic), prospective pilot, randomized controlled trial (RCT) in patients with an active DFU and no suspected clinical infection. Consenting patients were randomly assigned 1:1 to either treatment as usual informed by autofluorescence imaging (intervention), or treatment as usual alone (control). The primary outcome was the proportion of ulcers healed at 12 weeks by blinded assessment. Secondary outcomes included wound area reduction at 4 and 12 weeks, patient quality of life, and change in management decisions after autofluorescence imaging.

RESULTS

Between November 2017 and November 2019, 56 patients were randomly assigned to the control or intervention group. The proportion of ulcers healed at 12 weeks in the autofluorescence arm was 45% (n = 13 of 29) vs. 22% (n = 6 of 27) in the control arm. Wound area reduction was 40.4% (autofluorescence) vs. 38.6% (control) at 4 weeks and 91.3% (autofluorescence) vs. 72.8% (control) at 12 weeks. Wound debridement was the most common intervention in wounds with positive autofluorescence imaging. There was a stepwise trend in healing favoring those with negative autofluorescence imaging, followed by those with positive autofluorescence who had intervention, and finally those with positive autofluorescence with no intervention.

CONCLUSIONS

In the first RCT, to our knowledge, assessing the use of autofluorescence imaging in DFU management, our results suggest that a powered RCT is feasible and justified. Autofluorescence may be valuable in addition to standard care in the management of DFU.

Amputation and infection are the greatest fears in patients with diabetes foot complications

AIMS

To determine the degree patients with diabetic foot ulcers, Charcot neuroarthropathy and neuropathic fractures and dislocations fear complications (death, dialysis, heart attack, stroke, blindness, diabetic foot infection, minor and major lower extremity amputation [LEA]) that can occur and to assess if there is a difference between fears of patients with diabetic foot ulcers, Charcot neuroarthropathy and neuropathic fractures and dislocations and diabetic patients without these complications.

METHODS

478 patients completed an eight question Likert scale survey. The study group was defined as non-infected foot ulcers, neuropathic fractures and Charcot neuroarthropathy.

RESULTS

Of the 478 patients, 121 (25.3 %) had diabetic foot ulcers, Charcot neuroarthropathy or neuropathic fractures and dislocations and 357 (74.7 %) did not. The study group had significantly higher odds of reporting extreme fear of foot infection (OR 2.8, 95 % CI 1.8-4.5), major LEA (OR 2.8, 95 % CI 1.8-4.4), minor LEA (OR 2.3, 95 % CI 1.5-3.5), blindness (OR 2.0, 95 % CI 1.3-3.2), dialysis (OR 2.0, 95 % CI 1.1-3.3), and death (OR 2.4, 95 % CI 1.4-4.2). In the study group highest rated fear measures were foot infection (3.71, SD 1.23), minor amputation (3.67, SD 1.45) and major amputation (3.63, SD 1.52). There were no significant differences in the mean fear of infection, minor amputation or major amputation.

CONCLUSION

Patients with diabetic foot ulcers, Charcot neuroarthropathy or neuropathic fractures and dislocations reported higher fear ratings of diabetes-related complications compared to those without these complications.

Screening for identification of patients at high risk for diabetes-related foot ulcers: a cross-sectional study

Objective

Diabetes affected 463 million people globally in 2019, and this number is anticipated to reach 700 million by 2045. Diabetes results in lower limb amputation every 30 seconds. Egypt has a high prevalence of diabetic foot disease among patients with type 2 diabetes mellitus (T2DM). We aimed to identify high-risk patients for diabetic foot ulcers (DFUs) in Egypt.

Methods

We designed a cross-sectional study among adult patients with diabetes at Asyut University Hospital. Inlow’s 60-second diabetic foot screening tool was used to assess the risk of DFU. Neuropathy was assessed using the 10g monofilament test, and laboratory testing was performed to assess glycosylated hemoglobin (HbA1c) and diabetes control levels.

Results

Participants were aged 46.11 ± 9.18 years; 56% had T2DM and HbA1c levels >7%. In total, 47.9% of participants were at risk for DFUs. This risk was higher in patients who were older, male, widowed, working, illiterate, living in rural areas, and patients with diabetes duration >10 years, body mass index >32 kg/m², uncontrolled blood glucose levels, on an insulin regimen, and smokers.

Conclusions

Increasing health care providers’ awareness and ability to identify high-risk patients is critical to prevent DFUs and reduce the risk of amputation.

GelMA/PEGDA microneedles patch loaded with HUVECs-derived exosomes and Tazarotene promote diabetic wound healing

Clinical work and research on diabetic wound repair remain challenging globally. Although various conventional wound dressings have been continuously developed, the efficacy is unsatisfactory. The effect of drug delivery is limited by the depth of penetration. The sustained release of biomolecules from biological wound dressings is a promising treatment approach to wound healing. An assortment of cell-derived exosomes (exos) have been proved to be instrumental in tissue regeneration, and researchers are dedicated to developing biomolecules carriers with unique properties. Herein, we reported a methacrylate gelatin (GelMA) microneedles (MNs) patch to achieve transdermal and controlled release of exos and tazarotene. Our MNs patch comprising GelMA/PEGDA hydrogel has distinctive biological features that maintain the biological activity of exos and drugs in vitro. Additionally, its unique physical structure prevents it from being tightly attached to the skin of the wound, it promotes cell migration, angiogenesis by slowly releasing exos and tazarotene in the deep layer of the skin. The full-thickness cutaneous wound on a diabetic mouse model was carried out to demonstrate the therapeutic effects of GelMA/PEGDA@T + exos MNs patch. As a result, our GelMA/PEGDA@T + exos MNs patch presents a potentially valuable method for repairing diabetic wound in clinical applications.

Angiosome-guided endovascular revascularization for treatment of diabetic foot ulcers with peripheral artery disease

OBJECTIVE

Because diabetic foot ulcers (DFUs) are difficult to heal and cause huge economic losses to society, accelerating their healing has become extremely important. The purpose of this study was to evaluate the effect of revascularization based on the angiosome concept on DFU.

MATERIALS AND METHODS

Between January 2018 and July 2020, 112 consecutive legs with DFUs in 111 patients who were discharged from the vascular surgery department of our hospital were retrospectively evaluated. The legs were assigned to two groups depending on whether direct arterial flow to the foot ulcer based on the angiosome concept was achieved. Comparisons of the ulcer healing rate, mean time to ulcer healing, major amputation rate, survival rate, and major amputation-free survival rate between the angiosome direct revascularization (DR) and angiosome indirect revascularization (IR) groups were performed.

RESULTS

DR was achieved in 71 legs (63%) compared with IR in 41 legs. The ulcer healing rate (70.4% in the DR group vs. 34.1% in the IR group, P < 0.01), the mean time to ulcer healing (7.01 ± 4.26 months vs. 10.09 ± 3.24months, P < 0.01), the survival rate (90.1% vs. 53.7%, P < 0.01), and the major amputation-free survival rate (81.7% vs. 48.8%, P < 0.01) were significantly higher in the DR group than in the IR group. Undergoing DR did not significantly reduce the major amputations rate compared with IR (13.4% and 34.1%, respectively, P = 0.15), but there might be a trend. In multivariate models, DR remained a significant predictor for ulcer healing (HR, 7.07; 95% confidence interval, 6.54-7.60, P < 0.01). Opening multiple infrapopliteal arteries in the DR group compared with restoring only one infrapopliteal artery did not significantly improve the the ulcer healing rate (P = 0.59), the mean time to ulcer healing (P = 0.70), major amputation rate (P = 0.83), the survival rate (P = 0.31), and the major amputation-free survival rate(P = 0.40).

CONCLUSIONS

Attaining a direct arterial flow based on the angiosome concept may be important for ulcer healing, survival, and amputation-free survival in diabetic foot patients. Opening multiple infrapopliteal arteries in DR patients may not improve the ulcer healing, survival, major amputation or amputation-free survival compared with single DR vessel patency.

Role of Dipeptidyl Dipeptidase 4 Inhibitors in the Management of Diabetic Foot

Background: Patients with diabetes mellitus face difficulties in wound healing. It is important to explore therapeutic options for diabetic complications such as ulcers. This study evaluates the role of dipeptidyl dipeptidase 4 inhibitors (DPP4i) in the management of diabetic foot. Methods: Literature search was conducted in electronic databases (Google Scholar, Ovid, PubMed, Science Direct, and Springer) and studies were selected for inclusion if they reported the incidence rate of diabetic foot ulcer during DPP4i treatment or evaluated the effect of DPP4i on wound healing. Incidence rates of foot ulcer, amputation and peripheral vascular disease were pooled to achieve overall estimates. Meta-analyses of odds ratios were performed to evaluate the risk of foot ulcer, amputation, and peripheral vascular disease with DPP4i, and to examine the effect of DPP4i treatment on ulcer healing. Results: Ten studies (532354 DPP4i and 2092010 non-DPP4i treated diabetes patients) were included. Incidence rates of foot ulcer, amputation, and peripheral vascular disease were 3.80 [95% confidence interval (CI): 0.22, 7.39], 0.82 [95%CI: 0.60, 1.05], and 22.33 [95%CI: 9.14, 35.53] per 1000 person-years respectively in patients treated with DPP4i and 3.60 [95%CI: 1.77, 5.39], 0.76 [95%CI: 0.58, 0.94], and 20.9 [95%CI: 16.04, 25.81] per 1000 person-years respectively in patients treated with non-DPP4i drugs. Risk of ulcer or amputation with DPP4i was not consistent across studies. Odds of non-healing of ulcer were significantly lower with DPP4i in comparison with controls (odds ratio: 0.27 [95%CI: 0.10, 0.71]; p = 0.008). Conclusion: Incidence rates of diabetic foot and amputation are found to be similar with DPP4i and non-DPP4i drugs. DPP4i improved wound healing of diabetic foot in 3-month randomized trials.

Higher rates of all-cause mortality and resource utilization during episodes-of-care for diabetic foot ulceration

AIMS

Our primary objective was to determine whether all-cause rates of mortality and resource utilization were higher during periods of diabetic foot ulceration. In support of this objective, a secondary objective was to develop and validate an episode-of-care model for diabetic foot ulceration.

METHODS

We evaluated data from the Medicare Limited Data Set between 2013 and 2019. We defined episodes-of-care by clustering diabetic foot ulcer related claims such that the longest time interval between consecutive claims in any cluster did not exceed a duration which was adjusted to match two aspects of foot ulcer episodes that are well-established in the literature: healing rate at 12 weeks, and reulceration rate following healing. We compared rates of outcomes during periods of ulceration to rates immediately following healing to estimate incidence ratios.

RESULTS

The episode-of-care model had a minimum mean relative error of 4.2% in the two validation criteria using a clustering duration of seven weeks. Compared to periods after healing, all-cause inpatient admissions were 2.8 times more likely during foot ulcer episodes and death was 1.5 times more likely.

CONCLUSIONS

A newly-validated episode-of-care model for diabetic foot ulcers suggests an underappreciated association between foot ulcer episodes and all-cause resource utilization and mortality.

Ventral Windowed Total Contact Casts Safely Offload Diabetic Feet and Allow Access to the Foot

BACKGROUND

Irremovable total contact casts (TCCs) are the gold standard to offload diabetic foot ulcers (DFUs) and to immobilize feet with active Charcot neuro-osteoarthropathy (CN). They do not allow checks of the foot and are contraindicated in people with peripheral arterial disease (PAD). Frequently, removable TCCs and other removable devices are used because they allow wound care, modifications of the inner surface of the cast, and checks of the foot. The authors propose TCCs with ventral windows (VW-TCCs) whenever patients with high-risk conditions show poor adherence to wearing a removable cast all the time and access to the foot is necessary.

METHODS

This retrospective study compares treatments with bivalved, removable TCCs applied prior to the introduction of the novel design (from 1 January 2016 to 1 July 2017, "c") to treatments in the following period (t) with both bivalved removable TCCs and VW-TCCs in use.

RESULTS

Forty-five treatments after introduction (17 with the VW-TCC) showed a 52.8% lower median time to reach remission of the DFS than 41 controls (128/267 days, log-rank test P = .013). Reasons given for not using the novel design were: sufficient offloading with a removable TCC (16), patient preference (six), anatomical conditions (two), casts applied as a service for other facilities (three), and calf ulcers (one). Adverse effects from both designs were uncommon and not severe.

CONCLUSIONS

VW-TCCs combine advantages of both removable and irremovable TCCs. Complications do not limit the use, even in patients with PAD.

Surgical Management of Lower Extremity Wounds in the Solid Organ Transplant Patient Population: Surgeon Beware

Objective: To evaluate our institutional outcomes of surgical management of lower extremity (LE) wounds in the solid organ transplant recipient population. Approach: An 8-year retrospective review was conducted for all solid organ transplantation (SOT) recipients with LE wounds necessitating surgical management at our tertiary limb salvage center. Outcomes of interest included wound healing, surgical treatment, progression to amputation, and amputation level. Factors contributing to amputation progression were analyzed. The article adheres to the Strengthening the Reporting of Observational Studies in Epidemiology statement. Results: Sixty-four SOT recipients underwent surgical management for their LE wounds between 2010 and 2018. Median number of surgeries per patient was 5 (interquartile range = 2-8); 47 of 64 patients (73.4%) underwent amputation, and 17 of 64 patients (26.6%) underwent nonamputation surgical management. In the amputation group, the majority of primary amputations were minor (42/47, 89.4%); 24 of 42 (57.1%) patients progressed to a higher amputation level, 16 of 42 (38.1%) healed after their index procedure, and 2 of 42 (4.8%) were lost to follow-up (LTFU) after their primary minor amputation. Five of 47 (10.6%) patients undergoing amputations required primary below-knee amputations. In the nonamputation group, 15 of 17 (88.2%) healed, 1 of 17 (5.9%) expired, and 1 of 17 (5.9%) was LTFU. Innovation: To identify the outcomes of patients undergoing surgical management for LE wounds after SOT and elucidate clinical factors that impact the rate of limb salvage. Conclusions: This is the first comprehensive analysis of LE wounds in the transplant population. Our analysis indicates high rates of failed minor amputation, and frequent progression to major amputation in SOT patients. Preexisting comorbidities and immunosuppressive regimens complicate limb salvage; therefore, further research is warranted to optimize surgical LE wound management in this population.

Survival of Patients Following First Diagnosis of Diabetic Foot Complications: A Nationwide 15-Year Longitudinal Analysis

Background and Aims

The long-term survival in people with type 2 diabetes following first diagnosis of diabetic foot complications (FDDFC) is unclear. The object is to evaluate the mortality rate in subjects with type 2 diabetes following FDDFC and the impacts of the major cardiovascular comorbidities.

Methods

Nationwide data were analyzed for subjects with T2D and DFC between 2003 and 2017 according to ICD-9 coding. DFC was defined with the codes of ulcers, infections, or severe peripheral artery disease that required intervention (PAD) to mimic the real world diagnosis. Criteria of FDDFC were preceded by a period without any DFC for at least 5 years. Major cardiovascular comorbidities: established PAD and cardiovascular diseases (CVD: including coronary heart disease (CHD), stroke, or heart failure) before the index date as well as lower-extremity amputations (LEA) at the index episode were analyzed.

Results

Among 300,115 subjects with DFC, a total of 103,396 patients had FDDFC. The mean 5-year survival rate of these subjects was 81.05%. Using subjects without associated major cardiovascular comorbidity as baseline, the adjusted hazard ratios (aHR) were1.43 (95% confidence interval 1.38-1.49) in group PAD-/CVD+, followed by 1.70 (1.59-1.80) in PAD+/CVD- and 1.98 (1.89-2.08) in PAD+/CVD+. The aHR was further increased in patients with PAD who additionally had heart failure (3.77, 3.50-4.05), stroke (2.06, 1.95-2.18), or CHD (1.89, 1.79-2.00). Subjects with PAD rather than other CVD were associated with LEA at FDDFC. Patients with major LEA (above the ankle) at FDDFC episode had lower 5-year survival rate (65.01%) followed by those with minor LEA (72.24%) and without LEA (81.61%).

Conclusions

Cardiovascular comorbidity as well as LEA status at the event of FDDFCs were both associated with patient survival outcomes. Earlier identification of this large population could lead to higher survival rates.

Knowledge, attitude, and practice of diabetic patients regarding foot care: Experience from a single tertiary care outpatient clinic

BACKGROUND

Foot complications are a common problem among the diabetic population globally. Proper preventive education by health care providers should be provided to the diabetic population. This study aims to assess the knowledge, attitude, and practice of diabetic patients regarding foot care.

METHODS

This study was carried out in the medicine outdoor patient department of Allied Hospital, Faisalabad. A total sample of 150 diabetic patients was taken. Sampling was done through a non-probability convenient sampling technique. The data was analyzed using SPSS version 20.

RESULTS

The mean age of the respondents was 52.49 ± 11.87 years. Most of the patients had moderate knowledge and also practiced a moderate level of foot care. 32.7% of the patients had good knowledge, 51.3% had moderate knowledge, and 16.0% had poor knowledge regarding foot care. 63.3% of the patients had moderate practice; 24.5%, poor practice; and 12.2%, good practice. Patients belonging to urban areas scored better on both knowledge and practice scales. A significant statistical association of education with knowledge (P = 0.012) and practice (P = 0.008) regarding foot care was found. The patients compliant with drug therapy also observed better foot care practices.

CONCLUSION

Education had a significant role in positively influencing the behavior of the patients. There was found a gap between knowledge and practice level of patients. Hence patients should be actively engaged in their health care plan with more emphasis on changing their behavior.

A Comprehensive Review of the Pathogenesis, Diagnosis, and Management of Diabetic Foot Infections

GENERAL PURPOSE

To review an approach to diabetic foot infections (DFIs), including acute osteomyelitis, while also discussing current practices and the challenges in diagnosis and management.

TARGET AUDIENCE

This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care.

LEARNING OBJECTIVES/OUTCOMES

After participating in this educational activity, the participant will1. Identify the risk factors for developing DFIs.2. Outline diagnostic techniques for assessing DFIs.3. Select the assessment techniques that support a diagnosis of osteomyelitis.4. Choose the appropriate pharmacologic and nonpharmacologic treatment options for patients who have DFIs.

ABSTRACT

Diabetic foot ulcers result from a combination of peripheral neuropathy, vascular compromise, and repetitive trauma. Approximately 50% of individuals with diabetic foot ulcers will develop a diabetic foot infection (DFI), and 20% of individuals with a DFI will develop osteomyelitis. Herein, the authors review an approach to DFIs including acute osteomyelitis and discuss current practices and challenges in diagnosis and management.The diagnosis of a skin and soft tissue DFI is based on clinical criteria. A bone biopsy is considered the criterion standard for diagnosis of osteomyelitis; however, biopsy is not always feasible or available. Consequently, diagnosis can be made using a combination of clinical, biochemical, and radiographic findings. X-ray is the recommended imaging modality for initial evaluation; however, because of its lower relative sensitivity, advanced imaging may be used when clinical suspicion remains after negative initial testing.The microbiology of skin and soft tissue DFIs and osteomyelitis is similar. Staphylococcus aureus and other Gram-positive cocci are the most common pathogens identified. Deep cultures are preferred in both DFI and osteomyelitis to identify the etiologic pathogens implicated for targeted antimicrobial therapy. Management also requires a multidisciplinary approach. Surgical debridement in those with deep or severe infections is necessary, and surgical resection of infected bone is curative in cases of osteomyelitis. Finally, appropriate wound care is critical, and management of predisposing factors, such as peripheral neuropathy, peripheral arterial disease, tinea, and edema, aids in recovery and prevention.

Using motivational interviewing combined with digital shoe-fitting to improve adherence to wearing orthopedic shoes in people with diabetes at risk of foot ulceration: study protocol for a cluster-randomized controlled trial

Background

Diabetic foot ulcers have a high impact on mobility and daily functioning and lead to high treatment costs, for example, by hospitalization and amputation. To prevent (re)ulcerations, custom-made orthopedic shoes are considered essential. However, adherence to wearing the orthopedic shoes is low, and improving adherence was not successful in the past. We propose a novel care approach that combines motivational interviewing (MI) with a digital shoe-fitting procedure to improve adherence to orthopedic shoes. The aim of this trial is to assess the (cost-)effectiveness of this novel care approach compared to usual care (no MI and casting-based shoe-fitting) in promoting footwear adherence and ulcer prevention.

Methods

The trial will include people with diabetes, with IWGDF Risk categories 1–3, who have been prescribed orthopedic shoes. Participants will be randomized at the level of the podiatrist to the novel care approach or usual care. The primary outcome is the proportion of participants who adhere to the use of their orthopedic shoes, that is, who take at least 80% of their total daily steps with orthopedic shoes. A temperature microsensor will be built into the participants’ orthopedic shoes to measure wearing time continuously over 12 months. In addition, daily activity will be measured periodically using log data with an activity monitor. Data from the temperature microsensor and activity monitor will be combined to calculate adherence. (Re-)experienced complications after receiving orthopedic shoes will be registered. Questionnaires and interviews will measure the experiences of participants regarding orthopedic shoes, experiences of podiatrists regarding motivational interviewing, care consumption, and quality of life. Differences in costs and quality of life will be determined in a cost-effectiveness analysis.

Discussion

This trial will generate novel insights into the socio-economic and well-being impact and the clinical effectiveness of the novel care approach on adherence to wearing orthopedic shoes.

Trial registration

Netherlands Trial Register NL7710. Registered on 6 May 2019

The combined impact of ankle-brachial index and transcutaneous oxygen pressure on mortality in patients with type 2 diabetes and foot ulcers

AIMS

A diabetic foot ulcer (DFU) is associated with increased cardiovascular risk and mortality, independently of ulcer etiology (ischemic, neuro-ischemic or neuropathic). Ankle-brachial index (ABI) is the most commonly used test when diagnosing peripheral macrovascular disease and is a well-known marker for increased cardiovascular risk. Transcutaneous oxygen pressure (TcPO₂) is considered to better evaluate microvascular function and has in previous studies shown correlations with both wound healing and survival. The aim of this study was to evaluate the combined impact of a low TcPO₂ (<30 mmHg) and a pathological ABI (<0.9 or ≥1.4) on three-year mortality in patients with DFU.

METHODS

Type 2 diabetes patients aged <90 years, with at least one DFU who underwent vascular assessment with ABI and TcPO₂ were screened for participation. The primary endpoint was mortality after three years, assessed from the National Death Registry in Sweden.

RESULTS

The study enrolled 235 participants with a median age of 76 years. Individuals with either an abnormally high or low ABI in combination with a low TcPO₂ had the worst survival rates, with three-year mortality of 54%, compared to 42% in those with one abnormal variable (either ABI or TcPO₂), and 21% in those with normal ABI and TcPO₂.

CONCLUSIONS

Combining ABI and TcPO₂ when risk stratifying DFU patients seems to provide additional predictive information, not only concerning ulcer healing and limb salvage, but also on survival.

Mortality in 98 type 1 diabetes mellitus and type 2 diabetes mellitus: Foot ulcer location is an independent risk determinant

INTRODUCTION

We previously demonstrated in both a longitudinal study and in meta-analysis (pooled relative-risk RR, 2.45) that all-cause mortality is significantly higher in people with diabetes foot ulceration (DFU) than with those without a foot ulcer. In this prospective study, we looked at the factors linked to mortality after presentation to podiatry with DFU.

METHODS

Ninety-eight individuals recruited consecutively from the Salford Royal Hospital Multidisciplinary Foot Clinic in Spring 2016 were followed up for up to 48 months. Data concerning health outcomes were extracted from the electronic patient record (EPR).

RESULTS

Seventeen people (17) had type 1 diabetes mellitus, and 81 had type 2 diabetes mellitus. Thirty-one were women. The mean age (range) was 63.6 (28-90) years with maximum diabetes duration 45 years. Mean HbA1c was 72 (95% CI: 67-77) mmol/mol; 97% had neuropathy (International Working Group on the Diabetic Foot (IWGDF) monofilament); 62% had vascular insufficiency (Doppler studies); 69% of ulcers were forefoot, and 23% of ulcers were hind foot in location. Forty of 98 (40%) patients died in follow-up with 27% of death certificates including sepsis (not foot-related) and 35% renal failure as cause of death. Multivariate regression analysis indicated a 6.3 (95% CI: 3.9-8.1) fold increased risk of death with hind foot ulcer, independent of age/BMI/gender/HbA1c/eGFR/total cholesterol level.

CONCLUSION

This prospective study has indicated a very high long-term mortality rate in individuals with DFU, greater for those with a hind foot ulcer and shown a close relation between risk of sepsis/renal failure and DFU mortality, highlighting again the importance of addressing all risk factors as soon as people present with a foot ulcer.

Pharmacokinetics, Safety, and Tolerability of the α2C -Adrenoreceptor Antagonist BAY 1193397 in Healthy Male Subjects

The α_2C -adrenoreceptor antagonist BAY 1193397 is in development for the oral treatment of diabetic foot ulcers. Safety, tolerability, and pharmacokinetics of BAY 1193397 were investigated in 3 randomized, single-center phase 1 studies in healthy male subjects: a first-in-human study (single oral doses of 0.5-50 mg), a relative bioavailability and food effect study (single doses of 1 and 10 mg), and a multiple-dose escalation study (using 2 and 5 mg twice daily and 10 and 20 mg once daily for 9 consecutive days). BAY 1193397 was rapidly absorbed in the fasted state, peak concentrations were reached between 0.6 and 2 hours. The mean terminal half-life was in the range of 17 to 20 hours. Area under the plasma concentration-time curve and maximum concentration appeared to be dose proportional, with a negligible food effect. There were no high-accumulation effects of BAY 1193397 after repeated dosing. BAY 1193397 was safe and well tolerated. At supratherapeutic plasma concentrations, there were slight transient increases in norepinephrine levels, heart rate, and blood pressure that were more pronounced after a single dose compared to steady state and appeared to be maximum concentration dependent. The results of the presented studies support the conduct of subsequent clinical trials with BAY 1193397 in patients with diabetes and compromised microcirculation.

Patient perspectives on the physical, psycho-social, and financial impacts of diabetic foot ulceration and amputation

AIMS

Diabetic foot ulcers (DFUs) and ulceration are complex and lifelong problems for patients with diabetes which dramatically increase mortality rates. This qualitative study sought to capture detailed personal accounts and insights from patients with a clinical history of DFUs and amputations to better understand patient experiences.

METHODS

Fifteen patients from a tertiary referral center that treats diabetic foot problems were approached for participation. Inclusion criteria included having at least one DFU and being of white, Native American, or Hispanic background. Interviews were conducted by telephone by study staff trained in qualitative data gathering and audio recorded.

RESULTS

The main themes that emerged around impacts included the heavy burden of managing care, significant loss of ambulatory function, economic stress due to medical care costs and job loss, and emotional suffering tied to these stressors.

CONCLUSIONS

These data illuminate common social and personal impacts of diabetic foot problems across an ethnically and racially diverse and predominantly low-income US sample that expand our understanding of related declines in well-being. Our results indicate a need for proactive mental health assessment post DFUs diagnosis and the diversification of hospital and community-based support systems.

A Bibliometric Analysis of the Top-Cited Articles on Diabetic Foot Ulcers

The aim of this study was to determine the top-cited articles in the field of diabetic foot ulcer (DFU) research. A cross-sectional bibliometric analysis was conducted in January 2021 by using Boolean search terms in the Scopus and the Web of Science databases. The 50 top-cited articles that met the inclusion criteria were ranked and evaluated for several characteristics, including year of publication, country of origin, authorship, publishing journal, topic categories, publishing type, and level of evidence. The median number of citations per article in the list was 442 (interquartile range [IQR], 320-520), with a median of 21.8 citations (IQR, 16.5-34.5) per year since publication. The publication years ranged from 1986 to 2017, with 1998 accounting for the greatest number of studies (n = 7). The citation classics were published in 20 journals and originated from institutions in 9 countries. The majority of the studies were clinical, of which expert opinion/review with Level V evidence and clinical studies with Levels I and II evidence comprised the greater proportion in the list. This study provides useful insights into the history and development of DFU research. The top-cited list may serve as a quick reference for education curriculums and clinical practice, in addition to providing a foundation for further studies on this topic.

A Meta-Analysis of the Outcomes of Resection Arthroplasty for Resistant Hallucal Diabetic Ulcers

The standard medical care (SC) of non-infected diabetic foot ulcers (DFUs) has been reported to yield varying rates of wound healing with high recurrence rate in non-infected wounds. Conservative surgery has been advanced as an alternative to SC in treating resistant non-complicated and complicated DFUs. Studies reporting resection arthroplasty (RA) of the first metatarsal head stated high healing rates with less recurrence. The aim of this meta-analysis is to quantitatively assess the efficacy of the RA procedure. Based on 9 included studies (3 case-control and 6 case-series) with 225 patients (244 feet, 244 hallucal plantar ulcers) and a mean follow-up period was of 22.8 ±13.3 months, the weighted estimates of comparative studies (RA vs. SC) were as follows: healing rate (100% vs. 79.9%, p = .0001), time to heal (3.3 ±0.28 vs. 8.4 ±1.5 weeks, p = .002), recurrence rate (5.7% vs. 25.4%, p = .001) and transfer rate (4.5% vs. 1.4%, p = .1). Similar values were found when analyzing case-series of non-infected and infected wounds treated with RA. Based on the available evidence, resection arthroplasty of the first ray is to be considered an effective conservative surgery in treating resistant or complicated hallucal neuropathic ulcers. Further prospective controlled trials are warranted to validate the review findings.

Preulcerous Risk Situation in Diabetic Foot Syndrome: Proposal for a Simple Ulcer Prevention Score

BACKGROUND

Preulcerous risk situations in patients with diabetes are often undiagnosed and care administered too late. Even with regular medical check-ups and status documentation, foot examinations have not been given enough attention. Diagnosing an individual patients' risk of developing diabetic foot ulcers may increase vigilance for diabetic foot syndrome (DFS), and the appropriate prevention measures matching the risk involved may prevent the emergence of diabetic ulcers. The classical DFS risk factors are well established and have been extensively covered in the literature; however, there is a lack of efficient screening tools that could be used for a rapid assessment of diabetic foot ulcer risk.

METHODS

A methodical literature search was conducted to assess relevant publications for the preparation of a simple risk score for amputation related to diabetic foot ulcer. We then analyzed the risk factors for predictive value as odds ratios in foot ulcers and/or amputation. We used the available data to deduce a mean value to reflect the authors' consensus.

RESULTS

In view of the current literature on the matter, we have developed a semi-quantitative scoring system using just a few items to allow rapid and visual risk assessment for diabetic foot ulcers alongside recommendations for prevention and a sensible follow-up strategy to match the risk.

CONCLUSION

This relatively simple score enables rapid risk classification for patients that can ease the way for both physicians and patients in gaining an insight into individual risk situations. The score provides more effective preventative measures for high-risk patients against future complications.

Determinants of Success After Metatarsal Head Resection for the Treatment of Neuropathic Diabetic Foot Ulcers

Metatarsal head resection (MHR) is an effective option for the treatment of nonhealing neuropathic diabetic foot ulcers. The present study aimed to identify factors that predict treatment success for neuropathic diabetic foot ulcers undergoing metatarsal head resection. In this prospective interventional case series, 30 consecutive diabetic patients with documented nonischemic neuropathic plantar diabetic foot ulcers beneath the metatarsal head who underwent MHR were included. The study endpoint was demographic indicators of early and late postoperative outcomes. Patients were followed up for 1 to 66 months (mean 37.6 months). Except for 1 patient, all subjects' wounds (96.6%) healed after metatarsal head resection within an average of 35 days. One of the operated patients (3.4%) suffered short-term complications; long-term complications occurred in 23.3% of the patients. One patient (3.4%) experienced ulcer recurrence, 3 patients (10%) developed wound infection, and transfer lesions occurred in 3 other patients (10%) during the follow-up period. Using 3 estimators including ordinary least squares (OLS), White's heteroscedastic standard errors, and bootstrapping procedure, we could not find any statistically significant demographic feature related to ulcer healing. Using regression modeling, we could not find any evidence for a role of age, sex, weight, height, BMI, duration of ulcer until MHR, and duration of diabetes mellitus (years since diabetes diagnosis) affecting the outcome of MHR. Hence, demographic features, duration of ulcer until MHR, and years with diabetes did not affect the outcome of MHR. In conclusion, the authors believe that MHR will have a high rate of success for neuropathic wound healing in this specific subset of patients regardless of demographic features, as long as there is no ischemia to impair healing by secondary intention.

Plantar Foot Ulcer Recurrence in Neuropathic Patients Undergoing Percutaneous Tendo-Achilles Lengthening

Equinus contracture carries 3- and 4-fold associations with diabetes and plantar foot ulceration, respectively. Percutaneous tendo-Achilles lengthening is a useful method to alleviate peak plantar pressure resulting from equinus. We aimed to evaluate the effectiveness of percutaneous tendo-Achilles lengthening and estimate the relative longevity of the approach in reducing ulcer recurrence. The medical records of patients with equinus contracture who underwent percutaneous tendo-Achilles lengthening from 2010 to 2017 were reviewed. Included patients presented with plantar ulcers and a gastroc-soleus equinus of any angle <10° of ankle dorsiflexion with the affected knee extended and flexed. Patients who received concomitant tendon lengthening procedures (including anterior tibial tendon or flexor digitorum longus) were excluded. Outcome measures included time to wound healing, time to ulcer recurrence, and development of transfer lesion. Ninety-one patients underwent percutaneous tendo-Achilles lengthening with subsequent pedal ulceration without concomitant procedures. A total of 69 (75.8%) patients had a plantar forefoot ulcer, 7 (7.7%) had midfoot ulcers, 5 (5.5%) had hindfoot ulcers, and 3 (3.3%) had ulcers in multiple locations. Seven patients received prophylactic tendo-Achilles lengthening. At a mean follow-up of 31.6 months (±26), 66 (78.6%) wounds healed at a median 12.9 weeks. A total of 29 patients (43.9%) experienced ulcer recurrence at a mean of 12 months. Twelve patients (13%) experienced a transfer lesion at a mean of 16.6 months. Tendo-Achilles lengthening can be an effective adjunctive approach to achieve wound healing and reduce long-term ulcer recurrence in patients with equinus contracture and neuropathic plantar foot ulcers. A relengthening procedure may be needed within approximately 12 months from index surgery.

Long-term Mortality After Nontraumatic Major Lower Extremity Amputation: A Systematic Review and Meta-analysis

Chronic wounds that lead to major lower extremity amputation have immense consequences on quality of life, and ultimately, mortality. However, mortality rates after lower extremity amputation for a chronic wound are broad within the literature and have escaped precise definition. This systematic review aims to quantify long-term mortality rates after major lower extremity amputation in the chronic wound population available in the existing literature. Ovid MEDLINE was searched for publications which provided mortality data after major, nontraumatic, primary lower extremity amputations. Lower extremity amputations were defined as below and above the knee amputation. Data from included studies was analyzed to obtain pooled 1-, 2-, 3-, 5- and 10-year mortality rates. Sixty-one studies satisfied inclusion criteria representing 36,037 patients who underwent nontraumatic major lower extremity amputation. Pooled mortality rates were 33.7%, 51.5%, 53%, 64.4%, and 80% at 1-, 2-, 3-, 5- and 10-year follow-up, respectively. Within the 8184 diabetic patients (types 1 and 2), 1- and 5-year mortality was 27.3% and 63.2%. Sources of mortality data were varied and included electronic medical records, national health and insurance registries, and government databases. Mortality after nontraumatic major lower extremity amputation is high, both in patients with diabetes as well as those without. Methods used to measure and report mortality are inconsistent, lack reliability, and may underestimate true mortality rates. These findings illustrate the need for a paradigm shift in wound management and improved outcomes reporting. A focus on amputation prevention and care within a multidisciplinary team is critical for recalcitrant ulcers.

Effect of Mini-invasive Floating Metatarsal Osteotomy on Plantar Pressure in Patients With Diabetic Plantar Metatarsal Head Ulcers

BACKGROUND

Distal metatarsal osteotomy has been used to alleviate plantar pressure caused by anatomic deformities. This study's purpose was to examine the effect of minimally invasive floating metatarsal osteotomy on plantar pressure in patients with diabetic metatarsal head ulcers.

METHODS

We performed a retrospective case series of prospectively collected data on 32 patients with diabetes complicated by plantar metatarsal head ulcers without ischemia. Peak plantar pressure and pressure time integrals were examined using the Tekscan MatScan prior to surgery and 6 months following minimally invasive floating metatarsal osteotomy. Patients were followed for complications for at least 1 year.

RESULTS

Peak plantar pressure at the level of the osteotomized metatarsal head decreased from 338.1 to 225.4 kPa (P < .0001). The pressure time integral decreased from 82.4 to 65.0 kPa·s (P < .0001). All ulcers healed within a mean of 3.7 ± 4.2 weeks. There was 1 recurrence (under a hypertrophic callus of the osteotomy) during a median follow-up of 18.3 months (range, 12.2-27). Following surgery, adjacent sites showed increased plantar pressure and 4 patients developed transfer lesions (under an adjacent metatarsal head); all were managed successfully. There was 1 serious adverse event related to surgery (operative site infection) that resolved with antibiotics.

CONCLUSION

This study showed that the minimally invasive floating metatarsal osteotomy successfully reduced local plantar pressure and that the method was safe and effective, both in treatment and prevention of recurrence.

LEVEL OF EVIDENCE

Level III, retrospective case series of prospectively collected data.

Minor vs. major leg amputation in adults with diabetes: Six-month readmissions, reamputations, and complications

AIMS

The objective of this study was comparing medium-term outcomes between comparable minor and major amputations in adults with diabetes.

METHODS

We used data from the 2016-2017 National Readmissions Database to construct a representative cohort of 15,581 adults with diabetes with lower extremity amputations. Patients were categorized by level of index amputation (major/minor), and propensity score matched to compare outcomes in candidates for either level of amputation. Readmission and reamputations were assessed at 1, 3, and 6 months following index amputation.

RESULTS

In the 6 months following index amputation, large proportions of patients were readmitted (n = 7597, 48.8%) or had reamputations (n = 1990, 12.8%). Patients with minor amputations had greater odds of readmission (OR = 1.25; 95% CI 1.18-1.31), reamputation (OR = 3.71; 95% CI 3.34-4.12), and more proximal reamputation (OR = 2.61; 95% 2.33-2.93) (all P < 0.001). Further, minor amputation patients had higher and lower odds of readmission for postoperative infection (OR = 4.45; 95% CI 3.27-6.05), or sepsis (OR = 0.79; 95% CI 0.68-0.93), respectively.

CONCLUSION

Patients desire to save as much limb as possible and should be counseled on higher risk for reamputation, readmission, and infection with minor amputations.

Rates and risk factors for amputation in people with diabetes in Japan: a historical cohort study using a nationwide claims database

Background

The prevalence of diabetes is rising, and diabetes develops at a younger age in East Asia. Although lower limb amputation negatively affects quality of life and increases the risk of cardiovascular events, little is known about the rates and predictors of amputation among persons with diabetes from young adults to those in the “young-old” category (50–72 y).

Methods

We analyzed data from a nationwide claims database in Japan accumulated from 2008 to 2016 involving 17,288 people with diabetes aged 18–72 y (mean age 50.2 y, HbA1c 7.2%). Amputation occurrence was determined according to information from the claims database. Cox regression model identified variables related to lower limb amputation.

Results

The mean follow-up time was 5.3 years, during which time 16 amputations occurred (0.17/1000 person-years). Multivariate Cox regression analysis showed that age (hazard ratio [HR] 1.09 [95% confidence intervals] 1.02–1.16, p = 0.01) and HbA1c (HR 1.46 [1.17–1.81], p < 0.01) were independently associated with amputations. Compared with those aged < 60 years with HbA1c < 8.0%, the HR for amputation was 27.81 (6.54–118.23) in those aged ≥60 years and HbA1c ≥8.0%.

Conclusions

Age and HbA1c were associated with amputations among diabetic individuals, and the rates of amputation were significantly greater in those ≥60 years old and with HbA1c ≥8.0%.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-021-00474-8.

Long-term results after internal partial forefoot amputation (resection): a retrospective analysis

INTRODUCTION

Internal partial forefoot amputation (IPFA) is a treatment option for osteomyelitis and refractory and recurrent chronic ulcers of the forefoot. The aim of our study was to assess the healing rate of chronic ulcers, risk of ulcer recurrence at the same area or re-ulceration at a different area and revision rate in patients treated with IPFA.

MATERIALS AND METHODS

All patients who underwent IPFA of a phalanx and/or metatarsal head and/or sesamoids at our institution because of chronic ulceration of the forefoot and/or osteomyelitis from 2004 to 2014 were included. Information about patient characteristics, ulcer healing, new ulcer occurrence, and revision surgery were collected. Kaplan-Meier survival curves were plotted for new ulcer occurrence and revision surgery.

RESULTS

A total of 102 patients were included (108 operated feet). 55.6% of our patients had diabetes. In 44 cases, an IPFA of a phalanx was performed, in 60 cases a metatarsal head resection and in 4 cases an isolated resection of sesamoids. The mean follow-up was 40.9 months. 91.2% of ulcers healed after a mean period of 1.3 months. In 56 feet (51.9%), a new ulcer occurred: 11 feet (10.2%) had an ulcer in the same area as initially (= ulcer recurrence), in 45 feet (41.7%) the ulcer was localized elsewhere (= re-ulceration). Revision surgery was necessary in 39 feet (36.1%). Only one major amputation and five complete transmetatarsal forefoot amputations were necessary during the follow-up period. Thus, the major amputation rate was 0.9%, and the minor amputation rate on the same ray was 13.9%.

CONCLUSIONS

IPFA is a valuable treatment of chronic ulcers of the forefoot. However, new ulceration is a frequent event following this type of surgery. Our results are consistent with the reported re-ulceration rate after conservative treatment of diabetic foot ulcers. The number of major amputations is low after IPFA.

LEVEL OF EVIDENCE

Retrospective Case Series Study (Level IV).

Bacterial diversity and inflammatory response at first-time visit in younger and older individuals with diabetic foot infection (DFI)

AIM

Infection of a diabetic foot ulcer (DFU) is common. More than the half of DFUs become infected and 15-20% of them necessitate amputation in course of treatment. Diabetic foot infection (DFI) is therefore the major cause for non-traumatic lower limb amputation in Germany. Prompt and effective treatment of DFI is mandatory to safe limbs and lives. We investigated if there are relevant differences in evoked inflammatory response between different species and age-separated groups. We further investigated if there is an impact of ulcer localization on bacterial diversity.

METHODS

For a 12-month period, we investigated 353 individuals with infected DFU, their laboratory results and bacterial diversity at first-time visit in a Diabetic Foot Care Center in Southern Germany.

RESULTS

The ulcer microbiota was dominated by gram-positive species, primary Staphylococcus aureus. The gram-negative sector was mainly formed by Pseudomonas aeruginosa and Enterobacteriaceae (Proteus spp., Enterobacter spp., Escherichia coli and Klebsiella spp.). With increase in age, P. aeruginosa and S. aureus became more frequent, while Streptococci decreased. Ischemic and/or deep wounds were more likely to bear gram-negative species. Inflammatory response did not differ between gram-positive and gram-negative species, while Streptococci and Proteus spp. induced the highest serum inflammation reaction in their category. Streptococci, Enterobacter spp. and E. coli were more frequent in summer, while Enterococci spp., coagulase-negative Staphylococci and P. aeruginosa were more prevalent in winter half-year. DFIs of the forefoot and plantar side are mostly caused by gram-positive species, while Enterobacteriaceae were most frequent in plantar ulcerations.

CONCLUSION

Gram-positive species dominate bacterial spectrum in DFI. With increase in age, S. aureus, Streptococci and Pseudomonas aeruginosa became more frequent. The inflammatory response did not differ significantly between different species, but gram-negative species were slightly but not significant more frequent in ischemic wounds. Climatic distinction like summer or winter half-year as well as foot ulcer localization seems to influence bacterial diversity in DFUs.

Cumulative long-term recurrence of diabetic foot ulcers in two cohorts from centres in Germany and the Czech Republic

AIMS

Our aim was to comprehensively estimate the incidence of diabetic foot ulcer (DFU) recurrence and corresponding risk factors in two cohorts.

METHODS

Prospective data from patients with active DFU from two diabetes centres in Germany (GER, n = 222) and the Czech Republic (CZ, n = 99) were analysed. Crude cumulative incidences were obtained. Additionally, time to recurrence and risk factors were investigated using multivariate Cox models.

RESULTS

69%(154) of patients in GER and 70%(69) in CZ experienced at least one DFU recurrence; 25%(56) in DEU and 15%(15) in CZ died; 5%(11) and 9%(9) were lost to follow-up. The crude cumulative incidence in the first year was 28% in GER and 25% in CZ; 68%/70% within ten years, and 69%/70% in 15 years. In GER, renal replacement therapy was associated with shorter time to recurrence (HR = 3.71, 95%CI:1.26-10.87); no history of DFU before the index lesion with longer time to recurrence (HR = 0.62, 0.42-0.92). In CZ, type 2 diabetes (HR = 2.57, 1.18-5.62) and index ulcer treatment by minor amputation (HR = 2.11, 1.03-4.33) were associated with shorter time to recurrence.

CONCLUSIONS

Cumulative DFU recurrence was approximately 70% in 15 years in both cohorts. We found a significantly higher risk of future recurrence in patients having a consecutive ulcer compared with the first ever ulcer.

A Surgical Approach to Location-specific Neuropathic Foot Ulceration

The management of pedal ulcerations is often challenging because of a failure to correct underlying biomechanical deformities. Without correcting the biomechanical driving force creating the increased plantar pressures, it is unlikely for routine wound care to provide lasting solutions to pedal ulcerations. Patients with diabetes often experience glycosylation of their tendons, leading to contracture and pursuant deformity, creating imbalanced pressure distributions and eventual plantar ulceration. This article evaluates the efficacy of various lower extremity tendon transfers to balance the foot and redistribute plantar pressures to prevent or heal ulceration.

Combined (endo-)vascular intervention and microsurgical lower extremity free flap reconstruction-A propensity score matching analysis in 5386 ACS-NSQIP patients

BACKGROUND

Compromised lower limb perfusion due to vascular changes such as peripheral artery disease impedes wound healing and may lead to large-scale tissue defects and lower limb amputation. In such patients with defects and compromised or lacking recipient vessels, combined vascular reconstruction with free flap transfer is an option for lower extremity salvage.

METHODS

By using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database (2005-2018), we analyzed two patient cohorts undergoing (A) free flap lower limb reconstruction (LXTR) only and (B) combined (endo-)vascular reconstruction (vascLXTR). The preoperative variables assessed included demographic data and comorbidities, including smoking, diabetes mellitus, preoperative steroid use, and American Society of Anesthesiology (ASA) Physical Status Classification. Using a neighbor matching algorithm, we performed a 1:1 propensity score matching of 615 LXTR patients and 615 vascLXTR patients. Bivariate analysis for postoperative surgical and medical complications was performed for outcomes in the propensity-matched cohort.

RESULTS

We identified 5386 patients who underwent microsurgical free flap reconstruction of the lower extremity. A total of 632 patients underwent a combined (endo-)vascular intervention and lower extremity free flap reconstruction. Diabetes and smoking were more prevalent in this group, with 206 patients having diabetes (32.6%) and 311 being smokers (49.2%). More patients returned to the operating room in the cohort that underwent a combined vascular intervention (24.4% versus 9.9%; p<0.0001). The 30-day mortality for patients undergoing a combined vascular procedure was 3.5%, compared with 1.3% with free tissue transfer only (p<0.0001).

CONCLUSION

Despite the risks associated, the combined intervention decreases the very high mortality associated with limb amputation in severely sick patient populations. Careful preoperative assessment of modifiable risk factors may reduce complication rates while allowing limb salvage.

Health related quality of life (HRQoL) and its associated surgical factors in diabetes foot ulcer patients

Aim. To evaluate the health-related quality of life (HRQOL) in DFU patients and its association with different surgical parameters in a tertiary care teaching hospital. Methodology. A total of 70 DFU patients from surgery department were enrolled and their demographic details, surgical examination and treatment related parameter were recorded. HRQOL was evaluated using Cardiff Wound Impact Questionnaire. Association of different surgical parameters as predictors of HRQOL was statistically evaluated. Results. Mean age of the study patients was 53.92 ± 9.27 with male preponderance and male: female ratio of 1.5:1. All the patients in the study suffered from type 2 diabetes and mean duration of the diabetes was 8.0±1.4 year. Mean BMI of the study patients was 23.36 ±1.4. All patients of DFU showed deteriorated HRQOL with mean score of 42.2±15.13 in social domain, 17.12±7.43 in wellbeing, 75.33±27.06 in physical domain and total score of 146.56±45.46. Increasing age, female gender, increased BMI, alcohol addiction found to be significantly associated with the deteriorated quality of life with respect to all four major domains which include Social life (P<0.001), wellbeing (P<0.07), physical symptoms (P<0.001) and Overall Quality of life (P<0.001). Surgical parameters like treatment for ulcer, regular follow up, larger size of ulcer, more than one ulcer, and ulcer on planter surface and chronic and recurrent ulcer significantly affect social domain, wellbeing and physical symptoms and total score (p<0.05). Control of blood sugar levels with non-pharmacological measures, OHA or insulin significantly improve Qol (p<0.05). Conclusions. Surgical parameters like site, size, number and duration of ulcer, treatment and blood sugar control significantly affect Qol. Multidisciplinary approach with holistic view is required for management of DFU patients for better quality of life.

Lower extremity amputations and long-term outcomes in diabetic foot ulcers: A systematic review

BACKGROUND

Diabetes mellitus causes a large majority of non-traumatic major and minor amputations globally. Patients with diabetes are clinically complex with a multifactorial association between diabetic foot ulcers (DFU) and subsequent lower extremity amputations (LEA). Few studies show the long-term outcomes within the cohort of DFU-associated LEA.

AIM

To highlight the long-term outcomes of LEA as a result of DFU.

METHODS

PubMed/MEDLINE and Google Scholar were searched for key terms, “diabetes”, “foot ulcers”, “amputations” and “outcomes”. Outcomes such as mortality, re-amputation, re-ulceration and functional impact were recorded. Peer-reviewed studies with adult patients who had DFU, subsequent amputation and follow up of at least 1 year were included. Non-English language articles or studies involving children were excluded.

RESULTS

A total of 22 publications with a total of 2334 patients were selected against the inclusion criteria for review. The weighted mean of re-amputation was 20.14%, 29.63% and 45.72% at 1, 3 and 5 years respectively. The weighted mean of mortality at 1, 3 and 5 years were 13.62%, 30.25% and 50.55% respectively with significantly higher rates associated with major amputation, re-amputation and ischemic cardiomyopathy.

CONCLUSION

Previous LEA, level of the LEA and patient comorbidities were significant risk factors contributing to re-ulceration, re-amputation, mortality and depreciated functional status.

Diagnosing peripheral neuropathy in South-East Asia: A focus on diabetic neuropathy

Burning and stabbing pain in the feet and lower limbs can have a significant impact on the activities of daily living, including walking, climbing stairs and sleeping. Peripheral neuropathy in particular is often misdiagnosed or underdiagnosed because of a lack of awareness amongst both patients and physicians. Furthermore, crude screening tools, such as the 10-g monofilament, only detect advanced neuropathy and a normal test will lead to false reassurance of those with small fiber mediated painful neuropathy. The underestimation of peripheral neuropathy is highly prevalent in the South-East Asia region due to a lack of consensus guidance on routine screening and diagnostic pathways. Although neuropathy as a result of diabetes is the most common cause in the region, other causes due to infections (human immunodeficiency virus, hepatitis B or C virus), chronic inflammatory demyelinating polyneuropathy, drug-induced neuropathy (cancer chemotherapy, antiretrovirals and antituberculous drugs) and vitamin deficiencies (vitamin B1 , B6 , B12 , D) should be actively excluded.