Infrared thermography and ulcer prevention in the high-risk diabetic foot: data from a single-blind multicentre controlled clinical trial.

AIM: To assess the usefulness of monthly thermography and standard foot care to reduce diabetic foot ulcer recurrence. METHODS: People with diabetes (n = 110), neuropathy and history of ≥ 1 foot ulcer participated in a single-blind multicentre clinical trial. Feet were imaged with a novel thermal imaging device (Diabetic Foot Ulcer Prevention System). Participants were randomized to intervention (active thermography + standard foot care) or control (blinded thermography + standard foot care) and were followed up monthly until ulcer recurrence or for 12 months. Foot thermograms of participants from the intervention group were assessed for hot spots (areas with temperature ≥ 2.2°C higher than the corresponding contralateral site) and acted upon as per local standards. RESULTS: After 12 months, 62% of participants were ulcer-free in the intervention group and 56% in the control group. The odds ratios of ulcer recurrence (intervention vs control) were 0.82 (95% CI 0.38, 1.8; P = 0.62) and 0.55 (95% CI 0.21, 1.4; P = 0.22) in univariate and multivariate logistic regression analyses, respectively. The hazard ratios for the time to ulcer recurrence (intervention vs control) were 0.84 (95% CI 0.45, 1.6; P = 0.58) and 0.67 (95% CI 0.34, 1.3; P = 0.24) in univariate and multivariate Cox regression analyses, respectively. CONCLUSIONS: Monthly intervention with thermal imaging did not result in a significant reduction in ulcer recurrence rate or increased ulcer-free survival in this cohort at high risk of foot ulcers. This trial has, however, informed the design of a refined study with longer follow-up and group stratification, further aiming to assess the efficacy of thermography to reduce ulcer recurrence.

Reliability of a novel thermal imaging system for temperature assessment of healthy feet.

BACKGROUND: Thermal imaging is a useful modality for identifying preulcerative lesions ("hot spots") in diabetic foot patients. Despite its recognised potential, at present, there is no readily available instrument for routine podiatric assessment of patients at risk. To address this need, a novel thermal imaging system was recently developed. This paper reports the reliability of this device for temperature assessment of healthy feet. METHODS: Plantar skin foot temperatures were measured with the novel thermal imaging device (Diabetic Foot Ulcer Prevention System (DFUPS), constructed by Photometrix Imaging Ltd) and also with a hand-held infrared spot thermometer (Thermofocus® 01500A3, Tecnimed, Italy) after 20 min of barefoot resting with legs supported and extended in 105 subjects (52 males and 53 females; age range 18 to 69 years) as part of a multicentre clinical trial. The temperature differences between the right and left foot at five regions of interest (ROIs), including 1st and 4th toes, 1st, 3rd and 5th metatarsal heads were calculated. The intra-instrument agreement (three repeated measures) and the inter-instrument agreement (hand-held thermometer and thermal imaging device) were quantified using intra-class correlation coefficients (ICCs) and the 95% confidence intervals (CI). RESULTS: Both devices showed almost perfect agreement in replication by instrument. The intra-instrument ICCs for the thermal imaging device at all five ROIs ranged from 0.95 to 0.97 and the intra-instrument ICCs for the hand-held-thermometer ranged from 0.94 to 0.97. There was substantial to perfect inter-instrument agreement between the hand-held thermometer and the thermal imaging device and the ICCs at all five ROIs ranged between 0.94 and 0.97. CONCLUSIONS: This study reports the performance of a novel thermal imaging device in the assessment of foot temperatures in healthy volunteers in comparison with a hand-held infrared thermometer. The newly developed thermal imaging device showed very good agreement in repeated temperature assessments at defined ROIs as well as substantial to perfect agreement in temperature assessment with the hand-held infrared thermometer. In addition to the reported non-inferior performance in temperature assessment, the thermal imaging device holds the potential to provide an instantaneous thermal image of all sites of the feet (plantar, dorsal, lateral and medial views). TRIAL REGISTRATION: Diabetic Foot Ulcer Prevention System NCT02317835, registered December 10, 2014.

Barriers to foot care in patients with diabetes as identified by healthcare professionals.

AIMS: To seek the views of healthcare professionals as to the barriers to foot care that they perceive as having an impact on clinical outcomes and contributing to the number of amputations. METHODS: The study involved healthcare professionals from the UK attending our 2015 and 2016 Masterclass diabetic foot conferences. Admission to these conferences was open to all members of the multidisciplinary spectrum who provide care of people with diabetes and foot problems. Attendees were asked to write down concerns that they considered to constitute barriers to foot care for people with diabetes. RESULTS: A total of 425 responses were received (90.8% of the total attendance at the 2015/2016 conferences). Analysis of the responses produced eight key subject areas in which barriers to care were identified: patient referrals, communication between disciplines, access to specialist services, patient care, funding, organization of care, education and infection. Within these key areas, respondents reported poor recognition and diagnosis of foot problems, lack of awareness of the need for referral both by the person with diabetes and healthcare professionals, difficulties in the referral pathway, lack of access to multidisciplinary care, shortage of resources and lack of education of both people with diabetes and healthcare professionals. The respondents identified these barriers as contributing to delay in people with diabetes receiving specialist help. Such a delay can lead to amputation. CONCLUSIONS: The crucial barrier to diabetic foot care is delay in accessing specialist care. Until this is addressed, care will be less than optimum and amputations will continue.

Novel Semiquantitative Bone Marrow Oedema Score and Fracture Score for the Magnetic Resonance Imaging Assessment of the Active Charcot Foot in Diabetes.

There are no accepted methods to grade bone marrow oedema (BMO) and fracture on magnetic resonance imaging (MRI) scans in Charcot osteoarthropathy. The aim was to devise semiquantitative BMO and fracture scores on foot and ankle MRI scans in diabetic patients with active osteoarthropathy and to assess the agreement in using these scores. Three radiologists assessed 45 scans (Siemens Avanto 1.5T, dedicated foot and ankle coil) and scored independently twenty-two bones (proximal phalanges, medial and lateral sesamoids, metatarsals, tarsals, distal tibial plafond, and medial and lateral malleoli) for BMO (0-no oedema, 1-oedema < 50% of bone volume, and 2-oedema > 50% of bone volume) and fracture (0-no fracture, 1-fracture, and 2-collapse/fragmentation). Interobserver agreement and intraobserver agreement were measured using multilevel modelling and intraclass correlation (ICC). The interobserver agreement for the total BMO and fracture scores was very good (ICC = 0.83, 95% confidence intervals (CI) 0.76, 0.91) and good (ICC = 0.62; 95% CI 0.48, 0.76), respectively. The intraobserver agreement for the total BMO and fracture scores was good (ICC = 0.78, 95% CI 0.6, 0.95) and fair to moderate (ICC = 0.44; 95% CI 0.14, 0.74), respectively. The proposed BMO and fracture scores are reliable and can be used to grade the extent of bone damage in the active Charcot foot.

Increased Mortality in Diabetic Foot Ulcer Patients: The Significance of Ulcer Type.

Diabetic foot ulcer (DFU) patients have a greater than twofold increase in mortality compared with nonulcerated diabetic patients. We investigated (a) cause of death in DFU patients, (b) age at death, and (c) relationship between cause of death and ulcer type. This was an eleven-year retrospective study on DFU patients who attended King's College Hospital Foot Clinic and subsequently died. A control group of nonulcerated diabetic patients was matched for age and type of diabetes mellitus. The cause of death was identified from death certificates (DC) and postmortem (PM) examinations. There were 243 DFU patient deaths during this period. Ischaemic heart disease (IHD) was the major cause of death in 62.5% on PM compared to 45.7% on DC. Mean age at death from IHD on PM was 5 years lower in DFU patients compared to controls (68.2 ± 8.7 years versus 73.1 ± 8.0 years, P = 0.015). IHD as a cause of death at PM was significantly linked to neuropathic foot ulcers (OR 3.064, 95% CI 1.003-9.366, and P = 0.049). Conclusions. IHD is the major cause of premature mortality in DFU patients with the neuropathic foot ulcer patients being at a greater risk.

Acute Charcot neuro-osteoarthropathy.

Charcot neuro-osteoarthropathy (CN) is one of the most challenging foot complications in diabetes. Common predisposing and precipitating factors include neuropathy and increased mechanical forces, fracture and bone resorption, trauma and inflammation. In the last 15 years, considerable progress has been made in the early recognition of the acute Charcot foot when the X ray is still negative (stage 0 or incipient Charcot foot). Recent advances in imaging modalities have enabled the detection of initial signs of inflammation and underlying bone damage before overt bone and joint destruction has occurred. Casting therapy remains the mainstay of medical therapy of acute CN. If timely instituted, offloading can arrest disease activity and prevent foot deformity. In cases with severe deformity, modern surgical techniques can correct the unstable deformity for improved functional outcome and limb survival. Emerging new studies into the cellular mechanisms of severe bone destruction have furthered our understanding of the mechanisms of pathological bone and joint destruction in CN. It is hoped that these studies may provide a scientific basis for new interventions with biological agents.

Undiagnosed severe sleep apnoea and diabetic foot ulceration - a case series based hypothesis: a hitherto under emphasized factor in failure to heal.

BACKGROUND: Although great progress has been made in managing diabetic foot disease, it continues to carry significant morbidity and mortality. Obstructive sleep apnoea (OSA) and diabetes frequently coexist and recent studies suggest significant under-recognition of OSA in those with diabetes. There are no current reports on the direct clinical impact of OSA on acute or chronic diabetic foot ulcer healing. CASE REPORT: We describe three cases with Type 2 diabetes and a mean BMI of 50 kg/m(2) in whom we believe undiagnosed severe OSA may have impeded the rate of recovery of acutely infected foot ulcers. Despite standard care whilst in hospital with optimization of glycaemia, daily wound care, ulcer offloading techniques including casting, it was difficult to achieve satisfactory granulation in the first two cases with previously unrecognized and hence untreated severe OSA (Apnoea-Hypopnea Index > 30) until correction had been achieved through continuous positive airway pressure therapy (CPAP). In the third case, despite all optimization techniques, healing has not been achieved and individuals' reluctance to consider CPAP may be one possible factor. DISCUSSION: We observe in three severely obese individuals with diabetes that untreated severe OSA may have contributed to delayed wound healing. We also observed an improvement in two individuals after institution of CPAP therapy. Clinicians managing the diabetic foot should consider investigating the presence of OSA in non-healing or slowly progressive foot ulcers when all other factors have been fully optimized.

Inflammatory and bone turnover markers in a cross-sectional and prospective study of acute Charcot osteoarthropathy.

AIMS: To assess markers of inflammation and bone turnover at presentation and at resolution of Charcot osteoarthropathy. METHODS: We measured serum inflammatory and bone turnover markers in a cross-sectional study of 35 people with Charcot osteoarthropathy, together with 34 people with diabetes and 12 people without diabetes. In addition, a prospective study of the subjects with Charcot osteoarthropathy was conducted until clinical resolution. RESULTS: At presentation, C-reactive protein (P = 0.007), tumour necrosis factor-α (P = 0.010) and interleukin-6 (P = 0.002), but not interleukin-1ß, (P = 0.254) were significantly higher in people with Charcot osteoarthropathy than in people with and without diabetes. Serum C-terminal telopeptide (P = 0.004), bone alkaline phosphatase (P = 0.006) and osteoprotegerin (P < 0.001), but not tartrate-resistant acid phosphatase (P = 0.126) and soluble receptor activator of nuclear factor-κß ligand (P = 0.915), were significantly higher in people with Charcot osteoarthropathy than in people with and without diabetes. At follow-up it was found that tumour necrosis factor-α (P = 0.012) and interleukin-6 (P = 0.003), but not C-reactive protein (P = 0.101), interleukin-1ß (P = 0.457), C-terminal telopeptide (P = 0.743), bone alkaline phosphatase (P = 0.193), tartrate-resistant acid phosphatase (P = 0.856), osteoprotegerin (P = 0.372) or soluble receptor activator of nuclear factor-kß ligand (P = 0.889), had significantly decreased between presentation and the 3 months of casting therapy time point, and all analytes remained unchanged from 3 months of casting therapy until resolution. In people with Charcot osteoarthropathy, there was a positive correlation between interleukin-6 and C-terminal telopeptide (P = 0.028) and tumour necrosis factor-α and C-terminal telopeptide (P = 0.013) only at presentation. CONCLUSIONS: At the onset of acute Charcot foot, serum concentrations of tumour necrosis factor-α and interleukin-6 were elevated; however, there was a significant reduction in these markers at resolution and these markers may be useful in the assessment of disease activity.

Medical management of Charcot arthropathy.

Charcot arthropathy is a major complication of diabetes and it poses management challenges to health care professionals. Early diagnosis and timely intervention are essential for improved outlook of these patients. Casting therapy has been accepted as the mainstay treatment of the acute Charcot foot, although there are still controversies regarding its duration, the choice of removable and non-removable device and weight-bearing casts vs. non-weight-bearing casts. Two groups of antiresorptive therapies have been evaluated in the treatment of the acute Charcot foot, bisphosphonates (intravenous and oral) and calcitonin. These therapies have clearly shown a reduction of bone turnover, although, they have not shown a significant effect on temperature reduction. Current evidence to support their use is weak. An anabolic agent to speed up clinical resolution and fracture healing may be helpful and a clinical trial to evaluate the possible benefit of 1-84 recombinant human parathyroid hormone on fracture healing in the acute Charcot foot is in progress. This paper summarises the current approach to medical management of acute Charcot arthropathy with specific emphasis on casting and pharmacological therapy. Emerging new studies of the pathogenesis of this condition are also discussed.

Five-year follow-up of a cohort of people with their first diabetic foot ulcer: the persistent effect of depression on mortality.

AIMS/HYPOTHESIS: Depressive disorders are associated with mortality within 18 months of presentation of diabetic foot ulcers (DFU). The main aim of this study was to determine whether depressive disorder is still associated with increased mortality in people with their first foot ulcer at 5 years. METHODS: This is a 5-year follow-up of a cohort of 253 patients presenting with their first DFU. At baseline, the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) 2.1 was used to define those who met DSM-IV (Diagnostic and Statistical Manual 4th edition) criteria for depressive disorder. Cox regression analysis controlled for potential covariates: age, sex, marital status, socioeconomic status, smoking, mean HbA(1c), diabetes complications and ulcer severity. The main outcome was mortality at 5 years. RESULTS: The prevalence of DSM-IV depressive disorder at baseline was 32.2% (n = 82). There were 92 (36.4%) deaths over the 5 years of follow-up. In the Cox regression (n = 246), after adjusting for covariates, baseline DSM-IV depressive disorder was significantly associated with a twofold increased risk of mortality for any depressive episode (HR 2.09, 95% CI 1.34, 3.25), minor (HR 1.93, 95% CI 1.00, 3.74) or major depressive disorders (HR 2.18, 95% CI 1.31, 3.65), compared with patients who were not depressed. CONCLUSIONS/INTERPRETATION: Depression is associated with a persistent twofold increased risk of mortality in people with their first DFU at 5 years.

Audit of acute Charcot's disease in the UK: the CDUK study.

AIMS/HYPOTHESIS: We studied factors associated with the development and resolution of acute Charcot foot using a web-based observational study. METHODS: Clinicians managing cases of acute Charcot foot in the UK and Ireland between June 2005 and February 2007 were invited to register anonymised details on a secure website. RESULTS: A total of 288 cases (age 57.0 ± 11.3 years [mean ± SD]; 71.2% male) were registered from 76 centres. Of these, 36% of patients recalled an episode of relevant trauma in the preceding 6 months, while 12% had had surgery to the affected foot. In 101 (35%) cases, ulceration was present at registration and 20% of these had osteomyelitis. Non-removable off-loading devices were used at presentation in 35.4% of cases, with removable off-loading used in 50%. Data on resolution were available for 219 patients. The median time to resolution was 9 months in patients whose initial management included the use of non-removable off-loading, compared with 12 months in the remainder (p = 0.001). Bisphosphonates were administered intravenously in 25.4% and orally in 19.4% of cases. The median time to resolution in patients who received bisphosphonates was 12 months and was longer than in those who did not (10 months, p = 0.005). CONCLUSIONS/INTERPRETATION: The median time to resolution was longer than in earlier series. Although limited by being observational and non-randomised, these data suggest that the use of non-removable off-loading at presentation may shorten the time to resolution. They provide no evidence to indicate that the use of bisphosphonates is beneficial.

Thiazolidinediones induce osteocyte apoptosis and increase sclerostin expression.

AIMS: Thiazolidinediones (TZDs) are associated with a higher risk of bone fracture in women compared with men. The aim of the present study was to investigate whether TZDs could influence osteocyte behaviour and contribute to the skeletal phenotype observed in TZD-treated patients. METHODS: The murine MLO-Y4 cell line was used as a source of osteocytes. These cells were cultured for 24 h with 0, 10(-8) m, 10(-7) m, 10(-6) m, 10(-5) m or 10(-4) m of pioglitazone, rosiglitazone or troglitazone in the presence or absence of 17beta-oestradiol. The extent of osteocyte apoptosis was assessed, as was the expression of the bone formation inhibitor sclerostin and receptor activator for nuclear factor kappaB ligand (RANKL) also. RESULTS: In the absence of 17beta-oestradiol, pioglitazone, rosiglitazone and troglitazone induced osteocyte apoptosis dose-dependently even at the lowest concentration of 10(-8) m. Furthermore, the expression of sclerostin but not RANKL was significantly increased in TZD-treated cultures compared with untreated cultures. The presence of 17beta-oestradiol significantly reduced TZD-induced osteocyte apoptosis and also sclerostin up-regulation. CONCLUSIONS: These findings therefore raise the potential concern of using TZDs in post-menopausal women where the lack of oestrogen would not prevent osteocyte apoptosis and sclerostin up-regulation and may aggravate the reduction in bone mass in these patients.

Role of neuropathy on fracture healing in Charcot neuro-osteoarthropathy.

Charcot neuro-osteoarthropathy (CNO) is a devastating condition affecting most commonly the foot/ankle joint in diabetic patients and may lead to severe deformities and amputation. Peripheral sensory neuropathy seems to be a pre-requisite to the development of CNO. The aim of this review article is to summarise the skeletal effects of the nervous system on bone remodelling and fracture healing of normal and damaged joints and to describe how neuropathy, in the context of modern concept of neuro-osteopathology, is crucial in the predisposition of the patient to develop acute CNO.

Randomised controlled trial of the use of three dressing preparations in the management of chronic ulceration of the foot in diabetes.

OBJECTIVES: To determine the comparative effectiveness and cost-effectiveness of three dressing products, N-A, Inadine and Aquacel, for patients with diabetic foot ulcers, as well as the feasibility and consequences of less frequent dressing changes by health-care professionals. DESIGN: A multicentre, prospective, observer-blinded, parallel group, randomised controlled trial, with three arms. SETTING: Established expert multidisciplinary clinics for the management of diabetic foot ulcers across the UK. PARTICIPANTS: Patients over age 18 with type 1 or type 2 diabetes with a chronic (present for at least 6 weeks) full-thickness foot ulcer (on or below the malleoli) not penetrating to tendon, periosteum or bone, and with a cross-sectional area between 25 and 2500 mm(2). INTERVENTIONS: Participants were randomised 1:1:1 to treatment with one of N-A (a non-adherent, knitted, viscose filament gauze), Inadine (an iodine-impregnated dressing), both traditional dressings, or Aquacel, a newer product. MAIN OUTCOME MEASURES: The primary outcome measure was the number of ulcers healed in each group at week 24. Secondary measures included time to healing, new ulcerations, major and minor amputations, and episodes of secondary infection. RESULTS: A total of 317 patients were randomised. After 88 withdrawals, 229 remained evaluable. A greater proportion of smaller (25-100 mm(2) ulcers healed within the specified time (48.3% versus 37.3%; p = 0.048). There was, however, no difference between the three dressings in terms of percentage healed by 24 weeks, or in the mean time to healing, whether analysed on the basis of intention to treat (Inadine 44.4%, N-A 38.7%, Aquacel 44.7%; not significant) or per protocol (Inadine 55.2%, N-A 59.4%, Aquacel 63.0%; not significant). There was no difference in the quality of healing, as reflected in the incidence of recurrence within 12 weeks. Likewise, there was no difference in the incidence of adverse events, although a greater proportion of those randomised to the non-adherent dressings were withdrawn from the study (34.9% versus 29.1% Aquacel and 19.4% Inadine; p = 0.038). The only statistically significant difference found in the health economic analysis was the cost associated with the provision of dressings (mean cost per patient: N-A 14.85 pounds, Inadine 17.48 pounds, Aquacel 43.60 pounds). The higher cost of Aquacel was not offset by the fewer dressings required. There was no difference in measures of either generic or condition-specific measures of quality of life. However, there was a significant difference in the change in pain associated with dressing changes between the first and second visits, with least pain reported by those receiving non-adherent dressings (p = 0.012). There was no difference in the costs of professional time, and this may relate to the number of dressing changes undertaken by non-professionals. Fifty-one per cent of all participants had at least one dressing change undertaken by themselves or a non-professional carer, although this ranged from 22% to 82% between the different centres. CONCLUSIONS: As there was no difference in effectiveness, there is no reason why the least costly of the three dressings could not be used more widely across the UK National Health Service, thus generating potentially substantial savings. The option of involving patients and non-professional carers in changing dressings needs to be assessed more formally and could be associated with further significant reductions in health-care costs. TRIAL REGISTRATION: Current Controlled Trials ISRCTN78366977.

Day-case angioplasty in diabetic patients with critical ischemia.

AIM: Recent studies have shown that percutaneous transluminal angioplasty (PTA) can be safely performed as a day-case procedure. Many centers consider diabetes mellitus as a contraindication to day-case PTA. In this study, the safety and efficacy of 95 day-case PTA in 66 diabetic patients with critical leg ischemia (CLI) were evaluated. METHODS: Diabetic patients with CLI were assessed in a one-stop multidisciplinary outpatient clinic. Sixty-six outpatients with CLI deemed suitable for radiological intervention by non-invasive imaging (ultrasound angiology or magnetic resonance angiography) were scheduled for day-case PTA. RESULTS: PTA was initially successful in 63 out of 66 patients (95%). In 3 patients (5%), PTA was not possible because the lesion could not be balloon dilated or crossed with a guide wire. Clinically suspected first, second and third re-stenosis confirmed by non-invasive studies occurred in 20 out of 63 (31%), 7 out of 20 (35%) and 2 out of 7 (28%) patients, respectively. Following PTA, debridement was performed in 11 patients (17%), minor amputation in 8 (13%) and major amputation in 3 (5%). Relief of the primary symptom of rest pain or healing of ulcers was achieved in 23 out of 32 (72%) and 25 out of 27 (92.5%) patients, respectively. No peri-interventional morbidity or mortality was encountered. CONCLUSION: PTA is feasible and safe as a day-case procedure in diabetic patients with CLI. Re-stenosis can be managed by repeat day-case PTA.

Increased osteoclastic activity in acute Charcot's osteoarthropathy: the role of receptor activator of nuclear factor-kappaB ligand.

AIMS/HYPOTHESIS: Our aims were to compare osteoclastic activity between patients with acute Charcot's osteoarthropathy and diabetic and healthy controls, and to determine the effect of the receptor activator of nuclear factor-kappaB ligand (RANKL) and its decoy receptor osteoprotegerin (OPG). METHODS: Peripheral blood monocytes isolated from nine diabetic Charcot patients, eight diabetic control and eight healthy control participants were cultured in the presence of macrophage-colony stimulating factor (M-CSF) alone, M-CSF and RANKL, and also M-CSF and RANKL with excess concentrations of OPG. Osteoclast formation was assessed by expression of tartrate-resistant acid phosphatase on glass coverslips and resorption on dentine slices. RESULTS: In cultures with M-CSF, there was a significant increase in osteoclast formation in Charcot patients compared with healthy and diabetic control participants (p=0.008). A significant increase in bone resorption was also seen in the former, compared with healthy and diabetic control participants (p<0.0001). The addition of RANKL to the cultures with M-CSF led to marked increase in osteoclastic resorption in Charcot (from 0.264+/-0.06% to 41.6+/-8.1%, p<0.0001) and diabetic control (0.000+/-0.00% to 14.2+/-16.5%, p<0.0001) patients, and also in healthy control participants (0.004+/-0.01% to 10.5+/-1.9%, p<0.0001). Although the addition of OPG to cultures with M-CSF and RANKL led to a marked reduction of resorption in Charcot patients (41.6+/-8.1% to 5.9+/-2.4%, p=0.001), this suppression was not as complete as in diabetic control patients (14.2+/-16.5% to 0.45+/-0.31%, p=0.001) and in healthy control participants (from 10.5+/-1.9% to 0.00+/-0.00%, p<0.0001). CONCLUSIONS/INTERPRETATION: These results indicate that RANKL-mediated osteoclastic resorption occurs in acute Charcot's osteoarthropathy. However, the incomplete inhibition of RANKL after addition of OPG also suggests the existence of a RANKL-independent pathway.

Charcot neuro-osteoarthropathy-current standards.

It is extremely important to have a high index of suspicion for Charcot neuro-osteoarthropathy (CN) and to encourage early presentation of the patient. This should be followed by a rapid diagnosis and early intervention, and with such a modern approach many CN can now be healed and deformity prevented. CN can be divided into two phases: acute active phase and chronic stable phase. The acute active phase includes those patients presenting early with normal X-ray and those presenting later with deformity and radiological changes of CN. The acute phase is characterized by unilateral erythema and oedema. The foot is at least 2 degrees C hotter than the contralateral foot. Patients should have initially an X-ray examination which, at this time, may be normal. We then proceed to two investigations: initially a technetium diphosphonate bone scan, which will detect early evidence of bone damage and also locate the site of this damage. If the result of the bone scan is positive, we would proceed to magnetic resonance imaging (MRI) examination, which would describe in more detail the nature of the bony damage. The aim of treatment is immobilization in a plaster cast until there is no longer evidence on X-ray of continuing bone destruction, and the foot temperature is within 2 degrees C of the contralateral foot. An alternative treatment is a prefabricated walking cast, such as the Aircast. A randomized controlled study of a single 90 mg pamidronate infusion has shown a significant reduction of the markers of bone turnover and skin temperature in treated, compared with control subjects although the fall in skin temperature was similar in both groups. There was a similar finding in a recent study with alendronate. Calcitonin has also been used in the acute stage and there was a more rapid transition to the stable chronic phase in the treated group compared with controls. In the chronic stable phase, the foot is no longer warm and red. There may still be oedema but the difference in skin temperature between the feet is usually less than 2 degrees C. The X-ray shows fracture healing, sclerosis and bone remodelling. The patient must now be rehabilitated and gradually moved from cast treatment to suitable footwear. The patient needs close observation to detect any relapse, which will be evident from further swelling and heat in the foot. Careful rehabilitation is always necessary after a long period in a cast.

Calcaneal bone mineral density in patients with Charcot neuropathic osteoarthropathy: differences between Type 1 and Type 2 diabetes.

AIMS: To measure bone density and neuropathy in both feet in Type 1 and Type 2 patients with unilateral Charcot osteoarthropathy and controls. METHODS: Calcaneal bone density, temperature and vibration thresholds were compared between 17 Type 1 diabetic patients with osteoarthropathy and 47 Type 1 controls and between 18 Type 2 diabetic patients and 48 Type 2 controls. As well as the Charcot foot, the non-Charcot foot was studied to assess osteopenia at onset of osteoarthropathy. RESULTS: In Type 1 diabetes, bone density was reduced in the non-Charcot foot compared with controls [Z-score: -1.7 ({-1.9}-{-1.4}) vs. -0.2 ({-1.1}-{0.5}), P < 0.0001, median (interquartile range)]; but not in Type 2 diabetes [Z-score: 0.15 ({-0.45}-{0.85}) vs. 0.3 ({-0.5}-{0.9}), P = 0.675]. Bone density in the Charcot foot was lower compared with the non-Charcot foot in both Type 1 [Z-score: -2.0 ({-2.8}-{-1.4}) vs. -1.7 ({-1.9}-{-1.4}), P = 0.018] and Type 2 diabetes [Z-score: -0.2 ({-1.4}-{0.1}) vs. 0.3 ({-0.5}-{0.9}), P = 0.001]. In Type 1 diabetes, bone density of the non-Charcot foot was reduced compared with that in Type 2 (P < 0.0001). Body mass index was lower in Type 1 than in Type 2 Charcot patients (P = 0.007). Type 2 patients had high temperature (P = 0.001) and vibration thresholds (P < 0.0001) in the non-Charcot foot compared with Type 2 controls whereas Type 1 patients had a high temperature threshold (P = 0.01) but not vibration threshold compared with Type 1 controls (P = 0.077). CONCLUSION: Bone density was reduced in the non-Charcot foot in Type 1 but not in Type 2 diabetes. Type 2 patients had high temperature and vibration thresholds in contrast to Type 1 patients who had a high temperature threshold only.

Safety and performance of a new non-adhesive foam dressing for the treatment of diabetic foot ulcers.

OBJECTIVE: This study aimed to document the safety and performance of a new non-adhesive foam dressing (Biatain Non-adhesive Dressing, Coloplast A/S) in the treatment of established foot ulcers in patients with diabetes. METHOD: This was an open non-comparative prospective study. Participants had an ankle brachial pressure index score of over 0.4 (neuro-ischaemic) and an ulcer bigger than 1 cm2 and less than 8 cm2 in any direction. The treatment period was six weeks. RESULTS: Thirty-five out of 37 patients completed the study. The mean wound area reduced from 5.4 cm2 to 2.5 cm2. Relative wound area reduced from 100% at baseline to 40% at week 6. 'Wearing comfort' improved throughout the study (p = 0.039). Maceration remained stable or improved. None of the four reported adverse events were device related. CONCLUSION: This study demonstrates that treatment of diabetic foot ulcers with Biatain Non-adhesive Dressing results in considerable wound area reduction and prevents any deterioration in maceration. The dressing is safe and effective in the management of these ulcers.