Guidelines on the prevention of 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 prevention of foot ulceration in persons with diabetes and updates the 2015 IWGDF prevention 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. We recommend to screen a person at very low risk for ulceration annually for loss of protective sensation and peripheral artery disease and persons at higher risk at higher frequencies for additional risk factors. For preventing a foot ulcer, educate the at‐risk patient about appropriate foot self‐care and treat any pre‐ulcerative sign on the foot. Instruct moderate‐to‐high risk patients to wear accommodative properly fitting therapeutic footwear, and consider instructing them to monitor foot skin temperature. Prescribe therapeutic footwear that has a demonstrated plantar pressure relieving effect during walking to prevent plantar foot ulcer recurrence. In patients that fail non‐surgical treatment for an active or imminent ulcer, consider surgical intervention; we suggest not to use a nerve decompression procedure. Provide integrated foot care for high‐risk patients to prevent ulcer recurrence. Following these recommendations will help health care professionals to provide better care for persons with diabetes at risk of foot ulceration, to increase the number of ulcer‐free days, and to reduce the patient and health care burden of diabetic foot disease.     

Studies of experimental hosiery in diabetic neuropathic patients with high foot pressures

High plantar pressures and painless trauma are associated with the development of foot ulcers in diabetic patients. Padded hosiery has been reported to reduce plantar pressures in patients at risk of ulceration. Using the optical pedobarograph we have studied 10 patients who regularly wore experimental padded hosiery for 6 months. The hosiery continued to provide substantial and significant reduction in peak forefoot pressures at 3 months (mean reduction 15.5%, p less than 0.01) and 6 months (17.6%, p less than 0.01), although the level of reduction was less than that seen at baseline (31.3%, p less than 0.05). In addition, commercially available hosiery designed as sportswear has been tested, and compared with experimental hosiery. Although these socks (with high or medium density padding) provided significant pressure reduction versus barefoot (mean 17.4% and 10.4%, p less than 0.01), this was not as great as that seen with experimental hosiery (27%, p less than 0.05). Thus the use of socks designed to reduce pressure stress on diabetic neuropathic feet is effective, and continues to be so for a considerable period of time. Commercially available sports socks may also have a place in the management of the diabetic insensitive foot.     

The Association Between Callus Formation,High Pressures and Neuropathy in Diabetic Foot Ulceration

The presence of an ulcer beneath callus on the diabetic foot has been a well-documented and common clinical finding. We have conducted a prospective study to examine whether callus can be used to predict plantar intrinsic neuropathic diabetic foot ulcer formation. Sixty-three diabetic patients (43 male, 25 Type 1), median age 62 years (IQ range 52, 67), median diabetes duration 17 years (IQ range 8,25) participated in the study. All had neuropathy and peak plantar foot pressures (measured using a dynamic optical pedobarograph) ⩾10 kg cm⁻². Calluses and previous ulcers were documented and classified. All ulcers occurring prior to and during the study were recorded, re-examination was 15.4 (range 10–22) months from baseline. Seven ulcers (6 patients) occurred during the study. Pressures were higher in the ulcer than non-ulcer sub-group (p = 0.04) with a relative risk of developing an ulcer of 4.7 for an area of elevated plantar pressure. This compares with a relative risk of 11.0 for an ulcer developing under an area of callus, and a relative risk of 56.8 for an ulcer developing on a site of previous ulceration. This study confirms that a history of previous ulceration is the highest risk factor for ulceration and demonstrates, for the first time, that the presence of plantar callus is highly predictive of subsequent ulceration. Careful history taking and examination of the foot to detect the presence of callus require no special training or equipment and callus should be recognized as a ‘high risk’ factor for foot ulceration.     

Abnormal foot pressures alone may not cause ulceration

Both rheumatoid arthritis and diabetes have been associated with the development of abnormally high pressures under the feet, and ulceration has been considered to be a problem in both conditions. In order to examine further the relationship between high foot pressure, neurological abnormalities, and ulceration, we have studied two groups of patients: (a) 38 diabetic patients and (b) 37 patients with rheumatoid arthritis who had similar clinical abnormalities of the feet. Thirty-two percent of diabetic patients had a history of plantar ulceration compared with none of the rheumatoid group (p less than 0.01). However, the diabetic group had considerably more severe neuropathy (peroneal nerve motor conduction velocity 35.4 +/- 4.8 m s-1 vs 44.4 +/- 5.2 m s-1 (mean +/- SD), p less than 0.001; vibration perception threshold 33.5 +/- 13.4 vs 16.9 +/- 10.9, p less than 0.001), with a similar frequency of elevated plantar pressures (51% vs 61%, NS). These data emphasize the importance of the loss of sensory awareness in the pathogenesis of diabetic foot ulceration, and suggest that high pressure alone is not a direct cause of ulceration.     

The diabetic foot: from art to science. The 18th Camillo Golgi lecture

Diabetic foot ulceration represents a major medical, social and economic problem all over the world. While more than 5% of diabetic patients have a history of foot ulceration, the cumulative lifetime incidence may be as high as 15%. Ethnic differences exist in both ulcer and amputation incidences, with both being less common in patients of Indian subcontinent origin living in the UK. Foot ulceration results from the interaction of several contributory factors, the most important of which is neuropathy. With respect to the management of acute Charcot neuroarthropathy in diabetes, recent studies suggest that bisphosphonates reduce disease activity as judged not only by differences in skin temperature, but also by assessing markers of bone turnover. The use of the total-contact cast is demonstrated in the treatment of acute Charcot feet and of plantar neuropathic ulcers. Histological evidence suggests that pressure relief results in chronic foot ulcers changing their morphological appearance by displaying some features of an acute wound. Thus, repetitive stresses on the insensate foot appear to play a major role in maintaining ulcer chronicity. It is hoped that increasing research activity in foot disease will ultimately result in fewer ulcers and less amputation in diabetes.Abbreviations BSAP bone-specific alkaline phosphatase - CN Charcot neuroarthropathy - RCW removable cast walker - TCC total-contact cast     

Prevention of foot ulcers in the at‐risk patient with diabetes: a systematic review

Prevention of foot ulcers in patients with diabetes is important to help reduce the substantial burden on both patient and health resources. A comprehensive analysis of reported interventions is needed to better inform healthcare professionals about effective prevention. The aim of this systematic review is to investigate the effectiveness of interventions to help prevent both first and recurrent foot ulcers in persons with diabetes who are at risk for this complication. We searched the available medical scientific literature in PubMed, EMBASE, CINAHL, and the Cochrane databases for original research studies on preventative interventions. We screened trial registries for additional studies not found in our search and unpublished trials. Two independent reviewers assessed data from controlled studies for methodological quality, and extracted and presented this in evidence and risk of bias tables. From the 13,490 records screened, 35 controlled studies and 46 non‐controlled studies were included. Few controlled studies, which were of generally low to moderate quality, were identified on the prevention of a first foot ulcer. For the prevention of recurrent plantar foot ulcers, there is benefit for the use of daily foot skin temperature measurements, and for therapeutic footwear with demonstrated plantar pressure relief, provided it is consistently worn by the patient. For prevention of ulcer recurrence, there is some evidence for providing integrated foot care, and no evidence for a single session of education.Surgical interventions have been shown effective in selected patients, but the evidence base is small. Foot‐related exercises do not appear to prevent a first foot ulcer. A small increase in the level of weight‐bearing daily activities does not seem to increase the risk for foot ulceration. The evidence base to support the use of specific self‐management and footwear interventions for the prevention of recurrent plantar foot ulcers is quite strong. The evidence is weak for the use of other, sometimes widely applied, interventions, and is practically non‐existent for the prevention of a first foot ulcer and non‐plantar foot ulcer.     

Pilot study of the effects of local pressure on microvascular function in the diabetic foot.

AIM: The aim of the study was to determine whether areas of the diabetic foot that experience high pressures during normal activity also demonstrate reductions in cutaneous microvascular flow and/or endothelial function. METHODS: Sixteen patients with diabetes mellitus and eight healthy, age-matched control subjects were recruited. Maps of dynamic pressure on the plantar aspect of both feet were recorded during a normal gait cycle, and the skin microvascular blood flow response to the endothelium-dependent vasodilator acetylcholine was assessed at the sites of highest and lowest plantar pressure over the metatarsal heads. RESULTS: Patients with diabetes had higher plantar pressures than control subjects (P = 0.002), but there were no significant differences in basal skin blood flow or acetylcholine response between the groups. In the patients, baseline flow was increased (P = 0.041) but the acetylcholine response reduced (P = 0.03) at the high-pressure compared with the low-pressure site; this was most apparent in those who were particularly at risk of ulceration due to high plantar pressures. CONCLUSIONS: Chronically raised plantar pressure in the diabetic foot is associated with increased basal skin blood flow, compared with lower pressure areas on the same foot. Further work is required to determine whether, and under what conditions, this additional hyperaemia is protective or maladaptive. In addition, high-pressure areas have a reduced responsiveness to an endothelium-dependent vasodilator, although the clinical significance of these changes is not clear.     

Severe peripheral neuropathy and elevated plantar pressures causing foot ulceration in pituitary gigantism

We report two patients with treated pituitary gigantism and peripheral neuropathy, one of whom has chronic foot ulceration. Detailed neurophysiologfcal assessment was performed on both patients. The patient with foot ulceration had clinical and neurophysiological evidence of severe neuropathy, whereas the patient without ulceration had only neurophysiological abnormalities. The sweating response to acetylcholine was markedly impaired in the feet of both patients, suggesting pedal autonomic denervation. Neither patient had evidence of diabetes mellitus and detailed investigation failed to reveal an alternative cause of peripheral neuropathy. Optical pedobarography revealed abnormally high pressure (>10 kg/cm²) under the metatarsal heads of both patients, one such area coinciding with the area of ulceration. Thus in pituitary gigantism elevated plantar pressures may contribute to the development of foot ulceration when severe peripheral neuropathy Is present. Furthermore, as in diabetes mellitus, impaired sweating may also increase the risk of ulceration as the resultant dry skin may develop fissures.     

Treatment of diabetic foot ulcer: an overview strategies for clinical approach

Diabetic foot disease is a major health problem, which concerns 15% of the 200 million patients with diabetes worldwide. Major amputation, above or below the knee, is a feared complication of diabetes. More than 60% of non-traumatic amputations in the western world are performed in the diabetic population. Many patients who undergo an amputation, have a history of ulceration. Major amputations increase morbility and mortality and reduce the patient's quality of life. Treatment of foot complications is one of the main items in the absorption of economic and health resources addressed to the diabetic population. It is clear that effective treatment can bring about a reduction in the number of major amputations. Over recent years, we have seen a significant increase in knowledge about the physiopathological pathways of this complication, together with improvements in diagnostic techniques, but above all a standardized conservative therapeutic approach, which allows limb salvage in a high percentage of cases. This target has been achieved in specialized centers. An important prelude to diabetic foot treatment is the differing diagnosis of neuropathic and neuroischemic foot. This differentiation is essential for effective treatment. Ulceration in neuropathic foot is due to biomechanical stress and high pressure, which involves the plantar surface of toes and metatarsal heads. Treatment of a neuropathic plantar ulcer must correct pathological plantar pressures through weight bearing relief. Surgical treatment of deformities, with or without ulcerations, is effective therapy. A neuropathic ulcer that is not adequately treated can become a chronic ulcer that does not heal. An ulcer that does not heal for many months has a high probability of leading to osteomyelitis, for which treatment with antibiotics is not useful and which usually requires a surgical procedure. Charcot neuroarthropathy is a particular complication of neuropathy which may lead to fragmentation or destruction of joints and bones. A well-timed diagnosis of Charcot neuroartropathy is essential to avoid deformities of chronic evolution. In the diabetic population peripheral vascular disease (PVD) is the main risk factor for amputation. If peripheral vascular disease is ignored, surgical treatment of the lesion cannot be successful. In diabetic patients, PVD is especially distal, but often fully involves the femoral, popliteal and tibial vessels. It can be successfully treated with either open surgical or endovascular procedures. Infection is a serious complication of diabetic foot, especially when neuroischemic: phlegmon or necrotizing fascitis are not only limb-threatening problems, but also life-threatening ones. In this case, emergency surgery is needed. Primary and secondary prevention of foot ulceration is the main target. Prevention programs must be carried out to highlight risk factors, lowering amputation incidence.     

The effect of callus removal on dynamic plantar foot pressures in diabetic patients.

Clinical observation suggests that neuropathic foot ulceration frequently occurs beneath plantar callosities and in areas of high dynamic shear and vertical stress underneath the foot during walking. Seventeen diabetic patients had dynamic foot pressure measurements made before and after the removal of a total of 43 forefoot plantar callosities. Peak pressures (mean +/- SE) in the treated areas were reduced by 26% from 14.2 +/- 1.0 to 10.3 +/- 0.9 kg cm-2 (p less than 0.001), with reductions at 37 of the 43 sites and in all patients. Mean heel pressures were not significantly different (5.0 +/- 0.6 vs 4.9 +/- 0.6 kg cm-2). These results suggest that callus may act as a foreign body elevating plantar pressures and that a significant reduction in pressure is achieved by local chiropody treatment.     

The risk of foot ulceration in diabetic patients with high foot pressure: a prospective study

Summary Foot ulceration results in substantial morbidity amongst diabetic patients. We have studied prospectively the relationship between high foot pressures and foot ulceration using an optical pedobarograph. A series of 86 diabetic patients, mean age 53.3 (range 17–77) years, mean duration of diabetes 17.1 (range 1–36) years, were followed-up for a mean period of 30 (range 15–34) months. Clinical neuropathy was present in 58 (67%) patients at baseline examination. Mean peak foot pressure was higher at the follow-up compared to baseline (13.5 kg·cm^–2±7.1 SD vs 11.2±5.4, p<0.001) with abnormally high foot pressures (>12.3) being present in 55 patients at follow-up and 43 at the baseline visit (p=NS). Plantar foot ulcers developed in 21 feet of 15 patients (17%), all of whom had abnormally high pressures at baseline; neuropathy was present in 14 patients at baseline. Non-plantar ulcers occurred in 8 (9%) patients. Thus, plantar ulceration occurred in 35% of diabetic patients with high foot pressures but in none of those with normal pressures. We have shown for the first time in a prospective study that high plantar foot pressures in diabetic patients are strongly predictive of subsequent plantar ulceration, especially in the presence of neuropathy.     

Association of limited joint mobility and high plantar pressure in diabetic foot ulceration in Asian Indians

AIM: To investigate the association of limited joint mobility (LJM) and plantar foot pressure in Asian Indian diabetic subjects. SUBJECTS AND METHODS: The LJM and plantar pressure were measured in 345 consecutive subjects attending the foot clinic. The study groups were: Control-non-diabetic controls (n=50), DM-diabetic patients without neuropathy (n=100), DM+N-diabetic neuropaths (n=110) and DM+NU-diabetic neuropaths with past history of foot ulceration (n=85). Joint mobility was assessed using a goniometer. Plantar pressure was measured using the RS-Scan platform system. All subjects were able to walk comfortably unaided at their own pace. Data obtained on the metatarsal heads were used for analysis. Neuropathy status was assessed using the biothesiometer. RESULTS: The diabetic patients had higher prevalence of LJM and higher plantar pressure than control subjects (P<0.0001). Among the diabetic patients, those with neuropathy and history of plantar ulceration had higher LJM and plantar pressure compared to non-neuropaths (P<0.001). CONCLUSIONS: Both LJM and high plantar pressure appear to be important determinants of foot ulceration in susceptible neuropathic South Indian diabetic patients.     

Neurovascular disease,antioxidants and glycation in diabetes

People with diabetes are ten to fifteen times more likely to have a lower limb amputation (LLA) than non-diabetic individuals. Fifteen percent of people with diabetes will develop a foot ulcer during their lifetime, the rate of major amputation amongst diabetic individuals continues to rise, foot problems remain the commonest reason for diabetes-related hospitalisation and recurrence rates in patients with previous foot ulcers are 50% or more. Hyperglycaemia-induced oxidative stress has been shown to result in decreased nerve conduction velocity, and decreased endoneural blood flow-both precursors for neuropathy. Vitamin antioxidants have been shown to be effective therapy in experimental models in reducing free radical species and inhibiting the oxidative process in diabetes subjects. Little work has been published, however, regarding the dietary use of antioxidants from foods, and their specific effects on neurovascular disease and glycation within the diabetes population. Aetiological and prevention studies with dietary antioxidants from foods aimed at the complex nature of foot problems in diabetes are needed.     

An integrative review of therapeutic footwear for neuropathic foot due to diabetes mellitus

BackgroundTherapeutic footwear is built on a model of patient's foot, for people with diabetes suffering with neuropathy. Can the footwear helps to improve plantar pressure in neuropathic foot? This study focussed on available data on therapeutic footwear as an intervention for improving and offloading plantar pressure in neuropathic diabetic foot.MethodsRelevant scientific literature in PubMed, Medline and Google Scholar published between 2000 and 2017 were searched. The keywords searched were therapeutic footwear, plantar pressure, neuropathic foot, rocker sole, ulcer healing and offloading of plantar pressure. Articles on randomized controlled trials, observational, cohort, feasibility and factorial studies were reviewed.ResultsOne hundred and twenty five (125) articles were identified. The article comprised of 6 randomized controlled trials, 2 observational, 1 cohort, 1 feasibility and 1 factorial study met the inclusion criteria and were critiqued with a total enrolment of 1380 study subjects.ConclusionsThe review of the collated literature demonstrated that, therapeutic footwear can improve the healing of neuropathic diabetic foot ulcer by redistributing plantar pressure. However, the efficacy of therapeutic footwear requires the inclusion of technical features that should not be compromised from the design to the production of the footwear.     

Footwear for the neuropathic patient: offloading and stability

Diabetic neuropathy is related to plantar ulceration through a variety of factors of which increased plantar pressures and loss of protective sensation are the most important. Loss of sensation in the lower limbs is also related to postural instability and an increased risk of falling. Ankle and foot proprioception play an important role in postural control and this sensory function is also affected by neuropathy. It is conceivable that footwear, orthotics, casts and braces used for treatment or prevention of plantar ulceration through offloading of the injured or at-risk foot area can exacerbate the postural instability and risk of falling. This has, however, received very limited attention in the literature. There are studies that have demonstrated that footwear adjustments can influence balance and stability in healthy, elderly subjects. The adjustments made to footwear for the diabetic foot are generally more dramatic and, therefore, are expected to have a greater influence on postural stability. Furthermore, casts and braces tend to deviate even more from normal footwear. This may seriously interfere with normal gait and posture and, therefore, stability. So far the evidence suggests that patients wearing such devices demonstrate markedly reduced activity levels. This reduced activity could add to the effect of offloading. This could also be interpreted to indicate problems with stability. This presentation will review the different types of offloading interventions frequently used for ulcer treatment and prevention and will consider the mechanical effect of these interventions on stability.     

A longitudinal study of foot ulceration and its risk factors in community-based patients with type 2 diabetes: The Fremantle Diabetes Study

Aims

To determine the prevalence and associates of foot ulcer, and the subsequent incidence and predictors of first-ever hospitalisation for this complication, in well-characterised community-based patients with type 2 diabetes.

Methods

Baseline foot ulceration was ascertained in 1296 patients (mean age 64 years, 48.6% male, median diabetes duration 4.0 years) recruited to the longitudinal Fremantle Diabetes Study between 1993 and 1996. Incident hospitalisation for foot ulceration was monitored through validated data linkage until end-December 2010.

Results

At baseline, 16 participants (1.2%) had a foot ulcer which was independently associated with intermittent claudication, peripheral sensory neuropathy (PSN) and diabetes duration (P ≤ 0.01). The incidence of hospitalisation for this complication in those without prior/prevalent foot ulceration was 5.21 per 1000 patient-years. This rate and other published data suggest that 1 in 7–10 foot ulcers require hospitalisation. In a Cox proportional hazards model, intermittent claudication and PSN were significant independent predictors of time to admission with foot ulceration, in addition to retinopathy, cerebrovascular disease, HbA_1c, alcohol consumption, renal impairment, peripheral arterial disease and pulse pressure (P ≤ 0.038).

Conclusions

These data confirm PSN as an important risk factor for foot ulceration but, in contrast to some other studies, peripheral arterial disease was also a major independent contributor. Associations between hospitalisation for foot ulcer and both retinopathy and raised pulse pressure suggest a role for local microvascular dysfunction, while alcohol may have non-neuropathic toxic effects on skin/subcutaneous structures. The multifactorial nature of foot ulceration complicating type 2 diabetes may have implications for its management.     

Pharmacotherapy as adjunctive treatment for serious foot wounds in the patient with diabetes: a case study

Chronic foot wounds in patients with diabetes present significant treatment challenges. A 54-year-old woman with type 2 diabetes and two wounds (one on the left great toe and the other on the left medial plantar surface) visited the clinic after the chronic wounds failed to respond to treatment such as hydrotherapy. Subsequent comprehensive care, including debridement; opening tunnels distal, proximal, and medial from the plantar wound; application of a growth factor-stimulant; and treatment with cilostazol to improve both macro- and microvascular circulation provided excellent wound healing. Amputation was avoided and the patient returned to her regular routine within 6 months. Pharmacotherapy may provide new adjunctive therapy options in the treatment of chronic foot wounds in patients with diabetes mellitus. Controlled clinical studies to ascertain the effects of this treatment are warranted.     

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.