A proof-of-concept study of the effectiveness of a removable device for offloading in patients with neuropathic ulceration of the foot: the Ransart boot

Brazilian Society of Angiology and Vascular Surgery 2023 guidelines on the diabetic foot

The diabetic foot interacts with anatomical, vascular, and neurological factors that challenge clinical practice. This study aimed to compile the primary scientific evidence based on a review of the main guidelines, in addition to articles published on the Embase, Lilacs, and PubMed platforms. The European Society of Cardiology system was used to develop recommendation classes and levels of evidence. The themes were divided into six chapters (Chapter 1 - Prevention of foot ulcers in people with diabetes; Chapter 2 - Pressure relief from foot ulcers in people with diabetes; Chapter 3 -Classifications of diabetic foot ulcers; Chapter 4 - Foot and peripheral artery disease; Chapter 5 - Infection and the diabetic foot; Chapter 6 - Charcot's neuroarthropathy). This version of the Diabetic Foot Guidelines presents essential recommendations for the prevention, diagnosis, treatment, and follow-up of patients with diabetic foot, offering an objective guide for medical practice.

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.

Guidelines on offloading foot ulcers in persons with diabetes (IWGDF 2019 update)

The International Working Group on the Diabetic Foot (IWGDF) has published evidence-based guidelines on the prevention and management of diabetic foot disease since 1999. This guideline is on the use of offloading interventions to promote the healing of foot ulcers in people with diabetes and updates the previous IWGDF guideline. We followed the GRADE methodology to devise clinical questions and critically important outcomes in the PICO format, to conduct a systematic review of the medical-scientific literature, and to write recommendations and their rationale. The recommendations are based on the quality of evidence found in the systematic review, expert opinion where evidence was not available, and a weighing of the benefits and harms, patient preferences, feasibility and applicability, and costs related to the intervention. For healing a neuropathic plantar forefoot or midfoot ulcer in a person with diabetes, we recommend that a nonremovable knee-high offloading device is the first choice of offloading treatment. A removable knee-high and removable ankle-high offloading device are to be considered as the second- and third-choice offloading treatment, respectively, if contraindications or patient intolerance to nonremovable offloading exist. Appropriately, fitting footwear combined with felted foam can be considered as the fourth-choice offloading treatment. If non-surgical offloading fails, we recommend to consider surgical offloading interventions for healing metatarsal head and digital ulcers. We have added new recommendations for the use of offloading treatment for healing ulcers that are complicated with infection or ischaemia and for healing plantar heel ulcers. Offloading is arguably the most important of multiple interventions needed to heal a neuropathic plantar foot ulcer in a person with diabetes. Following these recommendations will help health care professionals and teams provide better care for diabetic patients who have a foot ulcer and are at risk for infection, hospitalization, and amputation.

Feasibility of Percutaneous Bone Biopsy as Part of the Management of Diabetic Foot Osteomyelitis in a 100% Neuropathic, Grade 3 IDSA/IWGDF Population on an Outpatient Basis

The present study aimed to evaluate the feasibility of percutaneous bone biopsy in an ambulatory setting as part of the management of diabetic foot osteomyelitis (DFO) on an outpatient basis. DFO may complicate some cases of apparently nonsevere foot infections in patients with diabetes and greatly increase the risk of a lower extremity amputation. It has been suggested that bone culture-based antibiotic therapy is a predictive factor of success in patients with diabetes treated nonsurgically for osteomyelitis of the foot. It is recommended to identify the causative microorganism(s) by the means of either a surgical or percutaneous bone biopsy taken appropriately to select the proper antibiotic therapy. Percutaneous bone biopsy in patients not requiring surgery is, however, not performed in everyday practice as it should be according to the current recommendations. In the present retrospective study, we report a series of 23 consecutive patients with a suspicion of DFO in whom 28 bone samples were collected by percutaneous biopsy at the bedside in an outpatient setting. The percentage of positive cultures was in accordance with that reported in the literature. The mean number of isolates per specimen was 1.04. After a mean 12-month follow-up, the remission was almost of 78%. No adverse event related to the bone biopsy was noted. After a 1-year follow-up, no recurrence was recorded among the patients in remission. The results of the present study suggest that bedside percutaneous bone biopsy performed in the ambulatory setting is a valuable and safe tool in the management of DFO on an outpatient basis.

Use of GBT013, a Collagen-Based Dressing, for the Healing of Diabetic Foot Ulcers

The number of people with diabetes is expected to reach 592 million in the year 2035. Diabetic foot lesions are responsible for more hospitalizations than any other complication of diabetes. The aims of this study were to examine for the first time a new biocompatible and biodegradable tridimensional collagen-based matrix, GBT013, in humans for diabetic foot ulcer wound healing and to evaluate its ease of use to better define a protocol for a future clinical trial. Seven adult patients with a diabetic foot ulcer of grade 1A to 3D (University of Texas Diabetic Wound Classification) were treated using GBT013, a new collagen-based advance dressing and were monitored in two specialized foot care units for a maximum of 9 weeks. Five of seven wounds achieved complete healing in 4 to 7 weeks. Nonhealed ulcers showed a significant reduction of the wound surface (>44%). GBT013 was well tolerated and displayed positive wound healing outcomes as a new treatment strategy of chronic foot ulcers in diabetic patients.

The efficacy of removable devices to offload and heal neuropathic plantar forefoot ulcers in people with diabetes: a single-blinded multicentre randomised controlled trial

Non-removable offloading is the 'gold standard' treatment for neuropathic diabetic plantar forefoot ulcers. However, removable offloading is the common 'standard of care'. We compared three removable offloading devices for ulcer healing efficacy. In this multicentre, randomised controlled trial, 60 persons with neuropathic diabetic plantar forefoot ulcers were randomly assigned to wear a custom-made knee-high cast [BTCC (bivalved TCC)], custom-made ankle-high cast shoe or a prefabricated ankle-high forefoot-offloading shoe (FOS). Primary outcome was healing at 12 weeks. Dynamic plantar pressures, daily stride count and treatment adherence were assessed on a randomly selected subset (n = 35). According to intention-to-treat analysis, 58% of patients healed with BTCC [OR 0·77 (95% CI 0·41-1·45) versus FOS], 60% with cast shoe [OR 0·81 (95% CI 0·44-1·49) versus FOS] and 70% with FOS (P = 0·70). Mean ± SD peak pressure in kPa at the ulcer site was 81 ± 55 for BTCC, 176 ± 80 for cast shoe and 107 ± 52 for FOS (P = 0·005); stride count was 4150 ± 1626, 3514 ± 1380 and 4447 ± 3190, respectively (P = 0·71); percentage of 2-week intervals that patients wore the device <50% of time was 17·3%, 5·2% and 4·9%, respectively. Non-significant differences in healing efficacy between the three devices suggest that, when non-removable offloading is contraindicated or not available, each can be used for plantar forefoot ulcer offloading. Efficacy is lower than previously found for non-removable offloading maybe because suboptimal adherence and high stride count expose the patient to high repetitive stresses. These factors should be carefully considered in decision making regarding ulcer treatment.

The Role of Pressure Offloading on Diabetic Foot Ulcer Healing and Prevention of Recurrence

BACKGROUND

An increased plantar pressure is a causative factor in the development of plantar foot ulcers in people with diabetes mellitus, and ulcers are a precursor of lower extremity amputation.

METHODS

In this article, the evidence is reviewed that relieving areas of increased plantar pressure (ie, offloading) can heal plantar foot ulcers and prevent their recurrence.

RESULTS

Noninfected, nonischemic neuropathic plantar forefoot ulcers should heal in 6 to 8 weeks with adequate offloading. Recent meta-analyses and systematic reviews show that nonremovable knee-high devices are most effective. This is probably because they eliminate the problem of nonadherence with the use of a removable device. Studies show a large discrepancy between evidence-based recommendations on offloading and what is used in clinical practice. Many clinics continue to use methods that are less effective or have not been proven to be effective, while ignoring evidence-based methods. Strategies are proposed to address this issue, notably the adoption and implementation of recent international guidelines by professional societies and a stronger focus of clinicians on expedited healing. For the prevention of plantar foot ulcer recurrence in high-risk patients, 2 recent trials have shown that the incidence of recurrence can be significantly reduced with custom-made footwear that has a demonstrated pressure-relieving effect through guidance by plantar pressure measurements, under the condition that the footwear is worn.

CONCLUSION

This review helps to inform clinicians about effective offloading treatment for healing plantar foot ulcers and preventing their recurrence.

Comparison of Removable and Irremovable Walking Boot to Total Contact Casting in Offloading the Neuropathic Diabetic Foot Ulceration

BACKGROUND

Despite its efficacy in healing neuropathic diabetic foot ulcers (DFUs), total contact cast (TCC) is often underused because of technical limitations and poor patient acceptance. We compared TCC to irremovable and removable commercially available walking boots for DFU offloading.

METHODS

We prospectively studied 60 patients with DFUs, randomly assigned to 3 different offloading modalities: TCC (group A), walking boot rendered irremovable (i-RWD; group B), and removable walking boot (RWD; group C). Patients were followed up weekly for 90 days or up to complete re-epithelization; ulcer survival, healing time, and ulcer size reduction (USR) were considered for efficacy, whereas number of adverse events was considered for safety. Patients' acceptance and costs were also evaluated.

RESULTS

Mean healing time in the 3 groups did not differ (P = .5579), and survival analysis showed no difference between the groups (logrank test P = .8270). USR from baseline to the end of follow-up was significant (P < .01) in all groups without differences between the groups. Seven patients in group A (35%), 2 in group B (10%), and 1 in group C (5%) (Fisher exact test P = .0436 group A vs group C) reported nonsevere adverse events. Patients' acceptance and costs were significantly better in group C (P < .05).

CONCLUSIONS

Our results suggest that a walking boot was as effective and safe as TCC in offloading the neuropathic DFUs, irrespective of removability. The better acceptability and lesser costs of a removable device may actually extend the possibilities of providing adequate offloading.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Footwear and offloading interventions to prevent and heal foot ulcers and reduce plantar pressure in patients with diabetes: a systematic review

BACKGROUND

Footwear and offloading techniques are commonly used in clinical practice for preventing and healing of foot ulcers in persons with diabetes. The goal of this systematic review is to assess the medical scientific literature on this topic to better inform clinical practice about effective treatment.

METHODS

We searched the medical scientific literature indexed in PubMed, EMBASE, CINAHL, and the Cochrane database for original research studies published since 1 May 2006 related to four groups of interventions: (1) casting; (2) footwear; (3) surgical offloading; and (4) other offloading interventions. Primary outcomes were ulcer prevention, ulcer healing, and pressure reduction. We reviewed both controlled and non-controlled studies. Controlled studies were assessed for methodological quality, and extracted key data was presented in evidence and risk of bias tables. Uncontrolled studies were assessed and summarized on a narrative basis. Outcomes are presented and discussed in conjunction with data from our previous systematic review covering the literature from before 1 May 2006.

RESULTS

We included two systematic reviews and meta-analyses, 32 randomized controlled trials, 15 other controlled studies, and another 127 non-controlled studies. Several randomized controlled trials with low risk of bias show the efficacy of therapeutic footwear that demonstrates to relief plantar pressure and is worn by the patient, in the prevention of plantar foot ulcer recurrence. Two meta-analyses show non-removable offloading to be more effective than removable offloading for healing plantar neuropathic forefoot ulcers. Due to the limited number of controlled studies, clear evidence on the efficacy of surgical offloading and felted foam is not yet available. Interestingly, surgical offloading seems more effective in preventing than in healing ulcers. A number of controlled and uncontrolled studies show that plantar pressure can be reduced by several conservative and surgical approaches.

CONCLUSIONS

Sufficient evidence of good quality supports the use of non-removable offloading to heal plantar neuropathic forefoot ulcers and therapeutic footwear with demonstrated pressure relief that is worn by the patient to prevent plantar foot ulcer recurrence. The evidence base to support the use of other offloading interventions is still limited and of variable quality. The evidence for the use of interventions to prevent a first foot ulcer or heal ischemic, infected, non-plantar, or proximal foot ulcers is practically non-existent. High-quality controlled studies are needed in these areas.

Corneal confocal microscopy to assess diabetic neuropathy: an eye on the foot

Accurate detection and quantification of human diabetic peripheral neuropathy are important to define at-risk patients, anticipate deterioration, and assess new therapies. Easily performed clinical techniques such as neuro-logical examination, assessment of vibration perception or insensitivity to the 10 g monofilament only assess advanced neuropathy, i.e., the at-risk foot. Techniques that assess early neuropathy include neurophysiology (which assesses only large fibers) and quantitative sensory testing (which assesses small fibers), but they can be highly subjective while more objective techniques, such as skin biopsy for intra-epidermal nerve fiber density quantification, are invasive and not widely available. The emerging ophthalmic technique of corneal confocal microscopy allows quantification of corneal nerve morphology and enables clinicians to diagnose peripheral neuropathy in diabetes patients, quantify its severity, and potentially assess therapeutic benefit. The present review provides a detailed critique of the rationale, a practical approach to capture images, and a basis for analyzing and interpreting the images. We also critically evaluate the diagnostic ability of this new noninvasive ophthalmic test to diagnose diabetic and other peripheral neuropathies.

Off-loading the diabetic foot for ulcer prevention and healing

Retrospective and prospective studies have shown that elevated plantar pressure is a causative factor in the development of many plantar ulcers in diabetic patients and that ulceration is often a precursor of lower-extremity amputation. Herein, we review the evidence that relieving areas of elevated plantar pressure (off-loading) can prevent and heal plantar ulceration.There is no consensus in the literature concerning the role of off-loading through footwear in the primary or secondary prevention of ulcers. This is likely due to the diversity of intervention and control conditions tested, the lack of information about off-loading efficacy of the footwear used, and the absence of a target pressure threshold for off-loading. Uncomplicated plantar ulcers should heal in 6 to 8 weeks with adequate off-loading. Total-contact casts and other nonremovable devices are most effective because they eliminate the problem of nonadherence to recommendations for using a removable device. Conventional or standard therapeutic footwear is not effective in ulcer healing. Recent US and European surveys show that there is a large discrepancy between guidelines and clinical practice in off-loading diabetic foot ulcers. Many clinics continue to use methods that are known to be ineffective or that have not been proved to be effective while ignoring methods that have demonstrated efficacy.A variety of strategies are proposed to address this situation, notably the adoption and implementation of recently established international guidelines, which are evidence based and specific, by professional societies in the United States and Europe. Such an approach would improve the often poor current expectations for healing diabetic plantar ulcers.

Off-loading the diabetic foot for ulcer prevention and healing

BACKGROUND

Retrospective and prospective studies have shown that elevated plantar pressure is a causative factor in the development of many plantar ulcers in diabetic patients and that ulceration is often a precursor of lower extremity amputation. In this article, we review the evidence that relieving areas of elevated plantar pressure (off-loading) can prevent and heal plantar ulceration.

RESULTS

There is no consensus in the literature concerning the role of off-loading through footwear in primary or secondary prevention of ulcers. This is likely due to the wide diversity of intervention and control conditions tested, the lack of information about off-loading efficacy of the footwear used, and the absence of a target pressure threshold for off-loading. Uncomplicated plantar ulcers should heal in 6 to 8 weeks with adequate off-loading. The total contact cast and other nonremovable devices are most effective because they eliminate the problem of nonadherence to recommendations for using a removable device. Conventional or standard therapeutic footwear is not effective in ulcer healing. Recent United States and European surveys show a large discrepancy between guidelines and clinical practice in off-loading diabetic foot ulcers. Many clinics continue to use methods that are known to be ineffective or have not been proven effective, while ignoring methods that have been demonstrated to be efficacious.

CONCLUSIONS

A number of strategies are proposed to address this situation, notably the adoption and implementation of recently established international guidelines, which are evidence-based and specific, by professional societies in the United States and Europe. Such an approach would change the often poor current expectations for healing diabetic plantar ulcers.