The effects of ulcer size and site, patient's age, sex and type and duration of diabetes on the outcome of diabetic foot ulcers

Effect of WF10 (immunokine) on diabetic foot ulcer therapy: a double-blind, randomized, placebo-controlled trial

This randomized controlled trial was undertaken to evaluate the effect of WF10 (Immunokine) as an adjunct to the standard treatment of diabetic foot ulcer. A total of 40 participants were randomized into 2 groups of 20. One group underwent standard therapy combined with infusions of WF10, and 1 underwent standard therapy combined with placebo. The wound severity scores, which vary with the severity of infection and inflammation, necrotic and granulation tissues, and wound depth and area, were assessed weekly for 9 weeks. Before treatment, the wound severity scores were not significantly different statistically between the 2 groups (13.7 ± 2.8 and 12.9 ± 3.2). After 9 weeks, the WF10 group had a statistically significant decreased wound severity score compared with that of the placebo group (1.8 ± 1.9 versus 4.4 ± 5.3, respectively, p < .05). Subgroup analyses comparing the WF10 and placebo groups showed statistically significant decreases of infection and inflammation (0.0 ± 0.0 versus 0.8 ± 0.9, respectively, p < .01), necrotic tissue (0.0 ± 0.0 versus 0.8 ± 1.1, respectively, p < .01), and an increase of the amount of granulation tissue (0.1 ± 0.3 versus 0.8 ± 1.2, respectively, p < .05). The wound depth and wound area also decreased more in the WF10 group; however, these decreases were not statistically significant. No severe adverse events were observed throughout the observation period. We concluded that the addition of WF10 to standard wound care statistically significantly reduced the wound severity score, infection and inflammation, and necrotic tissue and enhanced the formation of granulation tissue.

Incidence, risk factors for amputation among patients with diabetic foot ulcer in a Chinese tertiary hospital

OBJECTIVES

The aim of this study was to evaluate the incidence of amputation among patients with diabetic foot ulcer (DFU) and risk factors for amputations.

METHODS

This is a retrospective study of 450 inpatients treated in a multi-discipline based diabetic centre, 306th Hospital of PLA during the period of January 2000-September 2009. Hospital admission and discharge information including patient profile, grade of DFU, co-morbidities and complications, laboratory data and final outcome were collected. The risk factors for amputation were determined using univariate and stepwise logistic regression analysis.

RESULTS

The overall amputation rate among DFU was 21.5%. Significant univariate risk factors for amputation were peripheral vascular disease (PVD), white blood cell (WBC) counts, neutrophil granulocyte percentage, hemoglobin, triglyceride, cholesterol, LDL-C, HDL-C and serum sCRP. Upon stepwise logistic regression analysis, only PVD (odds ratio 4.529, 95% CI 1.500-13.676), WBC (odds ratio 1.146, 95% CI 1.075-1.222), sCRP (odds ratio 1.041, 95% CI 1.002-1.082) and triglyceride (odds ratio -0.488, 95% CI 0.433-0.869) were significant risk factors.

CONCLUSIONS

The risk factors for amputation were presence of PVD, increased WBC, sCRP and decreased triglyceride.

Hemoglobin A1c predicts healing rate in diabetic wounds

Lower-extremity wounds are a major complication of diabetes. Hemoglobin A1c (HbA1c) reflects glycemia over 2–3 months and is the standard measure used to monitor glycemia in diabetic patients, but results from studies have not shown a consistent association of HbA1c with wound healing. We hypothesized that elevated HbA1c would be most associated with poor wound healing. To test this hypothesis we conducted a retrospective cohort study of 183 diabetic individuals treated at the Johns Hopkins Wound Center. Our primary outcome was wound-area healing rate (cm²/day). Calibrated tracings of digital images were used to measure wound area. We estimated coefficients for healing rate using a multiple linear regression model controlling for clustering of wounds within individuals and other common clinic variables. The study population was 45% female and 41% black with mean age of 61 years. Mean HbA1c was 8.0% and there were 2.3 wounds per individual (310 wounds total). Of all measures assessed, only HbA1c was significantly associated with wound-area healing rate. Specifically, for each 1.0% point increase in HbA1c, the daily wound-area healing rate decreased by 0.028 cm²/day (95% CI: 0.003, 0.0054, p=0.027). Our results suggest that glycemia, as assessed by HbA1c, may be an important biomarker in predicting wound healing rate in diabetic patients.

Two-Step Autologous Grafting Using HYAFF Scaffolds in Treating Difficult Diabetic Foot Ulcers: Results of A Multicenter, Randomized Controlled Clinical Trial With Long-Term Follow-up

This study evaluated the efficacy and tolerability of an autologous tissue-engineered graft—a 2-step HYAFF autograft—in the treatment of diabetic foot ulcers compared with standard care. In all, 180 patients with dorsal or plantar diabetic foot ulcers (unhealed for ≥1 month) were randomized to receive Hyalograft-3D autograft first and then Laserskin autograft after 2 weeks (n = 90; treatment group) or nonadherent paraffin gauze (n = 90; control group). Efficacy and adverse events were assessed weekly for 12 weeks, at 20 weeks, and at 18 months. The primary efficacy outcome was complete ulcer healing at 12 weeks. Wound debridement, adequate pressure relief, and infection control were provided to both groups. At 12 weeks, complete ulcer healing was similar in both groups (24% of treated vs 21% controls). A 50% reduction in ulcer area was achieved significantly faster in the treatment group (mean 40 vs 50 days; P = .018). Weekly percentage ulcer reduction was consistently higher in the treatment group. At 20 weeks, ulcer healing was achieved in 50% of the treated group as compared with 43% of controls. Dorsal ulcers had a 2.17-fold better chance of wound healing per unit time following autograft treatment ( P = .047). In a subgroup with hard-to-heal ulcers, there was a 3.65-fold better chance of wound healing following autograft treatment of dorsal ulcers ( P = .035). Adverse events were similar in both groups. The study results demonstrated the potential of this bioengineered substitutes to manage hard-to-heal dorsal foot ulcers.

Factors related to outcome of neuroischemic/ischemic foot ulcer in diabetic patients

OBJECTIVES

Peripheral vascular disease (PVD) is an important limiting factor for healing in neuroischemic or ischemic diabetic foot ulcer. The purpose of this study was to identify factors related to healing in patients with diabetes with foot ulcers and severe PVD.

METHODS

Patients with diabetes with a foot ulcer, consecutively presenting at a multidisciplinary foot center with a systolic toe pressure <45 mm Hg or an ankle pressure <80 mm Hg were prospectively included, followed according to a preset program, and with the exception of specified exclusions, subjected to angiography offered vascular intervention when applicable. All patients had continuous follow-up until healing or death irrespective of the type of vascular intervention.

RESULTS

One thousand one hundred fifty-one patients were included. Eighty-two percent had a toe pressure <45 mm Hg and 49% had an ankle pressure <80 mm Hg. Eight hundred one patients (70%) underwent an angiography. Out of these, 63% had vascular intervention, either percutaneous transluminal angioplasty (PTA; 39%) or reconstructive surgery (24%). Nine percent of the patients had one or more complications after angiography. PTA was multisegmental in 46% and to the crural arteries in 46%. Reconstructive surgery was distal in 51%. Age (P < .001), renal function impairment (P = .005), congestive heart failure (P = .01), number and type of ulcer (P < .001), and severity of PVD (P = .003) affected the outcome of ulcers. PTA and reconstructive vascular surgery increased the probability of healing without amputation (odds ratio [OR], 1.77 and 2.05, respectively).

CONCLUSION

Probability of ulcer healing is strongly related to comorbidity, extent of tissue involvement, and severity of PVD in patients with diabetes with severe PVD.

Epidemiology of diabetic foot and management of foot problems in India

Diabetes the global epidemic is rapidly increasing at an alarming rate. Developing countries like India harbor the majority of diabetic people and by the year 2030 AD India will have the largest number of diabetic patients. Diabetic foot is one of the common diabetic complications found in India. Both aerobic and anaerobic pathogens form the etiology for diabetic foot infection. Members of the Enterobacteriaceae family were the most prominent among the aerobes while members of the Genus Peptostreptococcus and Clostridium were most prominent among the anaerobes. Ulcers infected with anaerobic pathogens showed a longer healing time than ulcers infected with aerobic pathogens. Oxidative stress is one of the major markers of inflammatory response and oxidative stress markers such as lipid peroxidation, thiobarbituric acid reactive substance (TBARS), Superoxide Dismutase (SOD), Catalase, G Peroxidase, G-S Peroxidase and plasma total antioxidant play a major role in the nonhealing of diabetic foot ulcers. Growth factors such as platelet-derived growth factor (PDGF), transforming growth factor (VEGF), and epidermal growth factor (EGF) are needed for normal wound repair, while proteases such as matrix metalloproteinase (MMP) and serine proteases found in chronic wounds delay the healing process.

[Use of collagen and Aloe vera in ischemic wound treatment: study case]

The present study is a clinical case report of a patient with diabetes and hypertension, with an ischemic wound, treated with a non-conventional Aloe vera and collagen plastering. This study is part of an experimental research project, coordinated by professors and nurses that work together to discover new ways for wound treatment. This case was chosen among many patients. Data was collected through anamneses and physical examination of the patient's condition, the wound, and pictures were taken. The plastering was applied every day, and by the end of ten weeks, total healing was obtained. There was no discomfort or any other implication as a result of using the compound. In conclusion, the compound was well accepted and efficient in this particular case.

A systematic review of scoring systems for diabetic foot ulcers

AIMS

Foot ulcers are a common and important complication of diabetes. Variation in the clinical presentation of this disease has resulted in a paucity of evidence from comparable studies to guide optimal clinical management. A validated scoring system might help clinicians and researchers in everyday assessment and management of patients or the development and assessment of new therapies. The aim of the present review was to critically appraise the published literature of wound scoring systems for diabetic foot ulcers.

METHODS

An electronic search was performed using the EMBASE and MEDLINE databases from 1966 until 2009 for scoring systems for diabetic foot ulcers. The literature review conformed to PRISMA statement standards.

RESULTS

The literature search identified 197 articles, of which 180 were excluded. Eleven scoring systems and six validation or comparative studies are described.

CONCLUSIONS

Many scoring systems exist for classification of the diabetic foot, few of which have been validated. Detailed scoring systems offer a valuable method for the comparison of data from different diabetic foot centres. Simplistic scoring systems may be used in clinical practice and the choice of scoring system should be determined by the population under study.

Hyperbaric oxygen therapy facilitates healing of chronic foot ulcers in patients with diabetes

OBJECTIVE

Chronic diabetic foot ulcers are a source of major concern for both patients and health care systems. The aim of this study was to evaluate the effect of hyperbaric oxygen therapy (HBOT) in the management of chronic diabetic foot ulcers.

RESEARCH DESIGN AND METHODS

The Hyperbaric Oxygen Therapy in Diabetics with Chronic Foot Ulcers (HODFU) study was a randomized, single-center, double-blinded, placebo-controlled clinical trial. The outcomes for the group receiving HBOT were compared with those of the group receiving treatment with hyperbaric air. Treatments were given in a multi-place hyperbaric chamber for 85-min daily (session duration 95 min), five days a week for eight weeks (40 treatment sessions). The study was performed in an ambulatory setting.

RESULTS

Ninety-four patients with Wagner grade 2, 3, or 4 ulcers, which had been present for >3 months, were studied. In the intention-to-treat analysis, complete healing of the index ulcer was achieved in 37 patients at 1-year of follow-up: 25/48 (52%) in the HBOT group and 12/42 (29%) in the placebo group (P = 0.03). In a sub-analysis of those patients completing >35 HBOT sessions, healing of the index ulcer occurred in 23/38 (61%) in the HBOT group and 10/37 (27%) in the placebo group (P = 0.009). The frequency of adverse events was low.

CONCLUSIONS

The HODFU study showed that adjunctive treatment with HBOT facilitates healing of chronic foot ulcers in selected patients with diabetes.

Mathematical model of hyperbaric oxygen therapy applied to chronic diabetic wounds

The failure of certain wounds to heal (including diabetic foot ulcers) is a significant socioeconomic issue for countries worldwide. There is much debate about the best way to treat these wounds and one approach that is shrouded with controversy is hyperbaric oxygen therapy (HBOT), a technique that can reduce the risk of amputation in diabetic patients.In this paper, we develop a six species mathematical model of wound healing angiogenesis and use it to investigate the effectiveness of HBOT, compare the response to different HBOT protocols and study the effect of HBOT on the healing of diabetic wounds that fail to heal for a variety of reasons. We vary the pressure level (1 atm-3 atm), percentage of oxygen inspired by the patient (21%-100%), session duration (0-180 minutes) and frequency (twice per day-once per week) and compare the simulated wound areas associated with different protocols after three weeks of treatment.We consider a variety of etiologies of wound chronicity and show that HBOT is only effective in treating certain causes of chronic wounds. For a wound that fails to heal due to excessive, oxygen-consuming bacteria, we show that intermittent HBOT can accelerate the healing of a chronic wound but that sessions should be continued until complete healing is observed. Importantly, we also demonstrate that normobaric oxygen is not a replacement for HBOT and supernormal healing is not an expected outcome. Our simulations illustrate that HBOT has little benefit for treating normal wounds, and that exposing a patient to fewer, longer sessions of oxygen is not an appropriate treatment option.

Maggot secretions skew monocyte-macrophage differentiation away from a pro-inflammatory to a pro-angiogenic type

BACKGROUND

Maggots of the blowfly Lucilia sericata are used for the treatment of chronic wounds. Earlier we reported maggot secretions to inhibit pro-inflammatory responses of human monocytes. The aim of this study was to investigate the effect of maggot secretions on the differentiation of monocytes into pro-inflammatory (MØ-1) and anti-inflammatory/pro-angiogenic macrophages (MØ-2) as these cells play a central role in wound healing.

METHODOLOGY/PRINCIPAL FINDINGS

Freshly isolated monocytes were incubated with secretions and GM-CSF or M-CSF for 6 days and then stimulated with LPS or LTA for 18 h. The expression of cell surface molecules and the levels of cytokines, chemokines and growth factors in supernatants were measured. Our results showed secretions to affect monocyte-macrophage differentiation leading to MØ-1 with a partial MØ-2-like morphology but lacking CD163, which is characteristic for MØ-2. In response to LPS or LTA, secretions-differentiated MØ-1 produced less pro-inflammatory cytokines (TNF-alpha, IL-12p40 and MIF) than control cells. Similar results were observed for MØ-2 when stimulated with low concentrations of LPS. Furthermore, secretions dose-dependently led to MØ-1 and MØ-2 characterized by an altered chemokine production. Secretions led to MØ-2, but not MØ-1, producing enhanced levels of the growth factors bFGF and VEGF, as compared to control cells. The expression of cell-surface receptors involved in LPS/LTA was enhanced by secretions, that of CD86 and HLA-DR down-regulated, while receptors involved in phagocytosis remained largely unaffected.

CONCLUSIONS

Maggot secretions skew the differentiation of monocytes into macrophages away from a pro-inflammatory to a pro-angiogenic type.

Assessment of risk factors in diabetic foot ulceration and their impact on the outcome of the disease

AIMS

The current study aims to identify risk factors for diabetic foot ulcer and their impact on the outcome of the disease.

METHODS

Three hundred diabetic patients were enrolled in the study. One hundred eighty subjects with diabetic foot ulcer and 120 diabetic controls without foot lesions. All expected risk factors were studied in all patients and after a follow up period, patients with diabetic foot ulcer were classified into group A (patients with healed ulcers) and group B (patients with persistent ulcer or ended by amputation). The risk factors were reanalyzed in both groups to find out their impact on the outcome of the disease.

RESULTS

The following variables were significant factors for foot ulceration: Male gender (P=0.009), previous foot ulcer (P=0.003), peripheral vascular disease (P=0.004), and peripheral neuropathy (P=0.006). Also lack of frequent foot self-examination was independently related to foot ulcer risk. The outcome was related to longer diabetes duration (P=0.004), poor glycaemic control (P=0.006) and anaemia (P=0.003) and presence of infection (P<0.001).

CONCLUSIONS

Peripheral vascular disease and peripheral neuropathy together with lack of foot self-examination, poor glycaemic control and anaemia are main significant risk factors for diabetic foot ulceration.

Emerging Evidence for Neuroischemic Diabetic Foot Ulcers: Model of Care and How to Adapt Practice

Although neuropathic ulceration remains the commonest type of foot ulcers among patients with diabetes, recent data suggest that ischemic (and therefore, neuroischemic) ulcers are on the rise. The high prevalence and incidence of diabetes and its attendant foot complications, coupled with the current trend where increasingly diabetes care is being provided by general practitioners (primary care physicians) would mean that primary care practices are expected to see greater numbers of diabetic foot ulcer patients. Unfortunately, these settings are frequently ill-equipped to appropriately manage diabetic foot ulcers either due to lack of adequately trained personnel and access to multidisciplinary foot care teams. Whereas neuropathic foot ulceration may appear to be less challenging, neuroischemic or ischemic ulcers portend a higher risk of adverse outcomes, including non-healing, infection, amputation, and death. The last 2 decades have witnessed a paradigm shift from neuropathy as the main etiological factor in diabetic foot disease to an ever-increasing preponderance of ischemic and/or neuroischemic ulceration. Available literature does not always consider the limited access primary care practices have to specialized multidisciplinary foot care teams. Additionally, in the case of neuroischemic and/or ischemic ulcers, existing guidelines on their diagnosis and management are varied and unclear. This review aimed at providing a simple understanding to the complex evidence base for diagnosing and treating neuroischemic and/or ischemic ulcers in a primary care setting. It emphasizes the need for urgent vascular review in all patients with ischemic/ neuroischemic ulcers and advocates effective participation of vascular specialists in diabetic foot clinics and combined ward rounds.

Use of an acellular flowable dermal replacement scaffold on lower extremity sinus tract wounds: a retrospective series

A novel injectable human dermal matrix has been developed for the treatment of complex diabetic sinus tract wounds. Bioengineered grafts are commercially available that have been somewhat effective in treating chronic wounds such as diabetic foot ulcers; however, these bioengineered grafts are only available in sheet form. These therapies are less effective in treating complex or irregularly shaped wounds that demonstrate tunnels or extensions into deep soft tissue. One acellular graft (GRAFTJACKET, Matrix, Wright Medical Technology, Arlington, Tennessee) that has been shown to effectively treat open wounds is also available in a micronized form (GRAFTJACKET Xpress Scaffold, Wright Medical Technology). This human dermal graft forms a flowable soft tissue scaffold that can be delivered via syringe into tunneling wounds. In this retrospective series, 12 patients with deep tunneling wounds were treated with GRAFTJACKET Xpress Scaffold and followed for 12 weeks. Complete wound healing was achieved in 10 of 12 patients within the 12-week evaluation. The average time to complete healing was 8.5 weeks, whereas the average time to depth healing was 7.8 weeks. The data from the study suggest that this injectable human dermal matrix has unique properties that allow it to facilitate healing of complex tunneling diabetic foot ulcers. The material is easy to prepare and inject into the wound, thereby preventing the necessity of extensive surgical exposure. The matrix supports neo-subcutaneous tissue formation and allows the body to rapidly repair these wounds.

Complexity of factors related to outcome of neuropathic and neuroischaemic/ischaemic diabetic foot ulcers: a cohort study

AIMS/HYPOTHESIS

We sought to identify factors related to short-term outcome of foot ulcers in patients with diabetes treated in a multidisciplinary system until healing was achieved.

METHODS

Consecutively presenting patients with diabetes and worst foot ulcer (Wagner grade 1-5, below ankle) (n = 2,511) were prospectively followed and treated according to a standardised protocol until healing was achieved or until death. The number of patients lost to dropout was 31. The characteristics of the remaining 2,480 patients were: 1,465 men, age 68 +/- 15 years (range 18-96), type 1 diabetes 18%, type 2 diabetes 82% and insulin-treated 62%.

RESULTS

The healing rate without major amputation in surviving patients was 90.6% (n = 1,867). Sixty-five per cent (n = 1,617) were healed primarily, 9% (n = 250) after minor amputation and 8% after major amputation; 17% (n = 420) died unhealed. Out of 2,060 surviving patients, 1,007 were neuroischaemic (48.8%). In a multiple regression analysis, primary healing was related to co-morbidity, duration of diabetes, extent of peripheral vascular disease and type of ulcer. In neuropathic ulcers, deep foot infection, site of ulcer and co-morbidity were related to amputation. Amputation in neuroischaemic ulcers was related to co-morbidity, peripheral vascular disease and type of ulcer. Age, sex, duration of diabetes, neuropathy, deformity and duration of ulcer or site of ulcer did not have an evident influence on probability of amputation.

CONCLUSIONS/INTERPRETATION

Patients with diabetic foot ulcer suffer from multi-organ disease. Factors related to outcome are correspondingly complex.

An assessment of the accuracy and usability of a novel optical wound measurement system

AIMS

Measurement of wound size can predict healing and provide information to guide treatment. This study assesses a novel optical wound imaging system that creates a three-dimensional image of the ulcer.

METHODS

Using a new camera-based digital system and traditional elliptical wound measurements, 36 foot ulcers from 31 patients (aged 44-94 years, median 70 years) were examined during a 12-week period at two centres. Median diabetes duration was 18 years (range 6-56 years). Seventeen percent had Type 1 diabetes, 93% had peripheral neuropathy and 57% had peripheral artery disease. Twenty-five were reviewed consecutively, resulting in 76 ulcer examinations. Median ulcer size was 94 mm(2), with size ranging from 3.1 to 2195 mm(2).

RESULTS

Pearson, Spearman and Kendall rank coefficients showed a strong correlation (in all cases P < 0.001) between digital measurements of wounds against traditional hand-measured estimates. Intra-observer variation of wound length using digital elliptical measurement (DEM) gave a coefficient of variation of < 3.0%. Interobserver variation of wound length using DEM was < 6.5%. Variation from a standard known-size wound area was < 8.0% across 30 trials.

CONCLUSIONS

This study shows a strong correlation between digital and traditional measurement techniques. The system can be easily deployed in routine clinical practice, providing an objective visual record, allowing remote in-depth analysis.

Increased matrix metalloproteinase-9 predicts poor wound healing in diabetic foot ulcers

OBJECTIVE

We studied the relationships of diabetic ulcer wound fluid matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), and transforming growth factor-beta1 (TGF-beta1) with wound healing rate.

RESEARCH DESIGN AND METHODS

The ulcers were cleansed to remove exudates, and wound fluids were collected for analysis of MMP-2 and -9, TIMP-1, and TGF-beta1.

RESULTS

At presentation, MMP-9 and the MMP-9-to-TIMP-1 ratio correlated inversely with the wound healing rate at 28 days (P < 0.001). MMP-9 and the MMP-9-to-TIMP-1 ratio were lower in the 23 patients who achieved complete healing at 12 weeks versus the 39 who did not. The pro-MMP-9 concentration was predictive of healing within 12 weeks. Addition of cutoffs for TIMP-1 (>480 pg/ml) and TGF-beta (>115 pg/ml) further improved its predictive power (area under the curve 0.94).

CONCLUSIONS

These findings suggest that a milieu with high MMP-9 may be indicative of inflammation and poor wound healing. Measurements of MMP-9, TIMP-1, and TGF-beta in wound fluid may help to identify ulcers at risk of poor healing.

Patients' perspectives on foot complications in type 2 diabetes: a qualitative study

BACKGROUND

Foot ulceration is a major health problem for people with diabetes. To minimise the risk of ulceration, patients are advised to perform preventive foot self-care.

AIM

To explore beliefs about diabetic foot complications and everyday foot self-care practices among people with type 2 diabetes.

DESIGN OF STUDY

Qualitative study using one-to-one interviews.

SETTING

A suburban primary care health centre.

METHOD

Semi-structured interviews with a purposive sample of adults with type 2 diabetes but with no experience of foot ulceration.

RESULTS

Most participants were unsure of what a foot ulcer is and unaware of the difficulties associated with ulcer healing. Prevention of accidental damage to the skin was not considered a priority, as few participants knew that this is a common cause of foot ulceration. Although it was recognised that lower-limb amputation is more common in people with diabetes, this was perceived to be predominantly caused by poor blood supply to the feet and unrelated to foot ulceration. Therefore, preventive foot care focused on stimulating blood circulation, for example by walking barefoot. Consequently, some of the behaviours participants considered beneficial for foot health could potentially increase the risk of ulceration. In some cases the uptake of advice regarding preventive foot care was hampered because participants found it difficult to communicate with health professionals.

CONCLUSION

Patients with type 2 diabetes may have beliefs about foot complications that differ from medical evidence. Such illness beliefs may play a role in foot-related behaviours that have previously been unrecognised. Health professionals need to explore and address the beliefs underlying patients' foot self-care practices.

Does the proximity of an amputation, length of time between foot ulcer development and amputation, or glycemic control at the time of amputation affect the mortality rate of people with diabetes who undergo an amputation?

OBJECTIVES

The main purpose of the authors' research was to compare the 3- and 5-year mortality rates of diabetic patients who have undergone a lower-extremity amputation, evaluating the proximity of the amputation in 3 groups (toe and foot amputation, BKA, and AKA), the timing of the amputation (within or after 2 years of the onset of the foot ulcer), and the effect of glycemic control at the time of amputation, regardless of the level of amputation.

METHODS AND DESIGN

The subjects were 80 male inpatients at Illiana Veterans Health Care System who had diabetes, diabetic neuropathy, peripheral vascular disease, and a diabetic foot ulcer that resulted in an amputation. Of the 80 patients, 29 had a toe amputation, 30 had a BKA, and 21 had an AKA. The mean age in all 3 groups was 68.5 years+/-7.2 years. The authors used the hemoglobin A1C (Hgb A1C) level to assess glycemic control.

MAIN OUTCOME MEASURES

Several chi tests were used to compare the 3- and 5-year mortality rates among the amputation groups. An Hgb A1C level of 8% or less defined good glycemic control; an Hgb A1C level of more than 8% defined poor glycemic control. A chi test was used to compare glycemic control, the level of amputation, and the mortality rate. A chi test was also used to evaluate the length of time between ulcer formation and amputation, the level of amputation, and the mortality. All statistics were done using SPSS 10.0 student version.

CONCLUSIONS

The research revealed a statistically significant difference in mortality among the 3 groups at 3 and 5 years. No statistically significant difference in mortality in patients with good glycemic control and patients with bad glycemic control was found. At 3 years, a statistically significant difference in mortality existed between patients who had an amputation within 2 years of ulcer formation and those who had an amputation after 2 years. At 5 years, no statistically significant difference existed between these 2 groups.

The development of global consensus guidelines on the management of the diabetic foot

The future for diabetes is grave. Now described as the global epidemic of the 21st century, the increasing incidence of diabetes (in 2007 over 246 million people affected by diabetes) will place considerable strain on resources and will bring suffering to many if the preventative measures promoted by the International Diabetes Federation (IDF), the International Working Group on the Diabetic Foot (IWGDF) and other diabetes representative organizations are not put into effect. Ulcers of the foot in diabetes are a source of major suffering and cost. Investing in a diabetic foot care guideline can be one of the most cost-effective forms of healthcare expenditure, provided the guideline is goal-focused and properly implemented. The objective of the IWGDF, founded in 1996, is to develop guidelines that will reduce the impact of diabetic foot disease through cost-effective and quality healthcare, based on the principles of evidence-based medicine. Three IWGDF working groups were invited to write specific consensus guidelines on different subjects, according to the current standards of evidence based medicine. Therefore, for the first time, new 2007 texts were produced according to a systematic review of the literature, in order to inform protocols for routine care and to highlight areas which should be considered for further study. After reaching worldwide consensus, the review reports and specific guidelines were launched in May 2007.

A systematic review of the effectiveness of interventions to enhance the healing of chronic ulcers of the foot in diabetes

The outcome of management of diabetic foot ulcers is poor and there is uncertainty concerning optimal approaches to management. We have undertaken a systematic review to identify interventions for which there is evidence of effectiveness. A search was made for reports of the effectiveness of interventions assessed in terms of healing, ulcer area or amputation in controlled clinical studies published prior to December 2006. Methodological quality of selected studies was independently assessed by two reviewers using Scottish Intercollegiate Guidelines Network (SIGN) criteria. Selected studies fell into the following categories: sharp debridement and larvae; antiseptics and dressings; chronic wound resection; hyperbaric oxygen (HBO); reduction of tissue oedema; skin grafts; electrical and magnetic stimulation and ultrasound. Heterogeneity of studies prevented pooled analysis of results. Of the 2251 papers identified, 60 were selected for grading following full text review. Some evidence was found to support hydrogels as desloughing agents and to suggest that a systemic (HBO) therapy may be effective. Topical negative pressure (TNP) may promote healing of post-operative wounds, and resection of neuropathic plantar ulcers may be beneficial. More information was needed to confirm the effectiveness and cost-effectiveness of these and other interventions. No data were found to justify the use of any other topically applied product or dressing, including those with antiseptic properties. Further evidence to substantiate the effect of interventions designed to enhance the healing of chronic ulcers is urgently needed. Until such evidence is available from robust trials, there is limited justification for the use of more expensive treatments and dressings.

The biology of chronic foot ulcers in persons with diabetes

Diabetic foot ulcers constitute a major health problem and they are recalcitrant to healing due to a constellation of intrinsic and extrinsic factors. The purpose of this article is to review the potential biological mechanisms that deter healing and perpetuate inflammatory responses in chronic diabetes foot ulcers. The link between hyperglycemia induced oxidative stress and its negative impact on cellular functions are explained. Key evidence related to alteration in tissue perfusion, bacterial balance, sustained proteases and cytokines release, leukocyte function, and growth factor production at the local wound level are summarized.

Prediction of outcome in individuals with diabetic foot ulcers: focus on the differences between individuals with and without peripheral arterial disease. The EURODIALE Study

AIMS/HYPOTHESIS

Outcome data on individuals with diabetic foot ulcers are scarce, especially in those with peripheral arterial disease (PAD). We therefore examined the clinical characteristics that best predict poor outcome in a large population of diabetic foot ulcer patients and examined whether such predictors differ between patients with and without PAD.

METHODS

Analyses were conducted within the EURODIALE Study, a prospective cohort study of 1,088 diabetic foot ulcer patients across 14 centres in Europe. Multiple logistic regression modelling was used to identify independent predictors of outcome (i.e. non-healing of the foot ulcer).

RESULTS

After 1 year of follow-up, 23% of the patients had not healed. Independent baseline predictors of non-healing in the whole study population were older age, male sex, heart failure, the inability to stand or walk without help, end-stage renal disease, larger ulcer size, peripheral neuropathy and PAD. When analyses were performed according to PAD status, infection emerged as a specific predictor of non-healing in PAD patients only.

CONCLUSIONS/INTERPRETATION

Predictors of healing differ between patients with and without PAD, suggesting that diabetic foot ulcers with or without concomitant PAD should be defined as two separate disease states. The observed negative impact of infection on healing that was confined to patients with PAD needs further investigation.

Procalcitonin as a diagnostic aid in diabetic foot infections

The diagnosis of diabetic foot infection (DFI) is usually a challenge to the clinician. Procalcitonin (PCT), a 116-amino acid propeptide of calcitonin, is a new marker of bacterial infections and sepsis. We evaluated the serum value of PCT as a marker of bacterial infection in diabetic patients with foot ulcers. Forty-nine diabetic patients with foot ulcers were consecutively enrolled into the study. DFI was diagnosed clinically by the presence of purulent secretions or at least two of the symptoms of inflammation including redness, warmth, swelling, and pain. According to these criteria, DFI was determined in 27 patients (DFI group) and not detected in 22 patients (NDFI group). The blood samples were taken for biochemical analysis on admission. PCT, white blood cell count (WBC) and erythrocyte sedimentation rate (ESR), but not C-reactive protein (CRP), was found significantly higher in DFI group compared with NDFI group. The best cut-off value, sensitivity and specificity were 0.08 ng/ml, 77% and 100% for PCT, 32.1 mg/dl, 29% and 100% for CRP, 8.6 10(9)/L, 70% and 72% for WBC and 40.5 mm/h, 77% and 77% for ESR, respectively. The area under the receiver operating characteristic curve for infection identification was greatest for PCT (0.859; p < 0.001), followed by WBC (0.785; p = 0.001), ESR (0.752; p = 0.003), and finally CRP (0.625; p = 0.137). These results suggest that PCT may be a useful diagnostic marker for DFI. Additional research is needed to better define the role of PCT in DFI.

Maggot debridement therapy of infected ulcers: patient and wound factors influencing outcome - a study on 101 patients with 117 wounds

INTRODUCTION

It has been known for centuries that maggots are potent debriding agents capable of removing necrotic tissue and slough. In January 2004, the US Food and Drug Administration decided to regulate maggot debridement therapy (MDT). As it is still not clear which wounds are likely or unlikely to benefit from MDT, we performed a prospective study to gain more insight in patient and wound characteristics influencing outcome.

PATIENTS AND METHODS

In the period between August 2002 and December 2005, patients with infected wounds with signs of gangrenous or necrotic tissue who seemed suited for MDT were enrolled in the present study. In total, 101 patients with 117 ulcers were treated. Most wounds were worst-case scenarios, in which maggot therapy was a treatment of last resort.

RESULTS

In total, 72 patients (71%) were classified as ASA III or IV. In total, 78 of 116 wounds (67%) had a successful outcome. These wounds healed completely (n = 60), healed almost completely (n = 12) or were clean at least (n = 6) at last follow-up. These results seem to be in line with those in the literature. All wounds with a traumatic origin (n = 24) healed completely. All wounds with septic arthritis (n = 13), however, failed to heal and led in half of these cases to a major amputation. According to a multivariate analysis, chronic limb ischaemia (odds ratio [OR], 7.5), the depth of the wound (OR, 14.0), and older age (>or= 60 years; OR, 7.3) negatively influenced outcome. Outcome was not influenced by gender, obesity, diabetes mellitus, smoking, ASA-classification, location of the wound, wound size or wound duration.

CONCLUSIONS

Some patient characteristics (i. e. gender, obesity, smoking behaviour, presence of diabetes mellitus and ASA-classification at presentation) and some wound characteristics (i. e. location of the wound, wound duration and size) do not seem to contra-indicate eligibility for MDT. However, older patients and patients with chronic limb ischaemia or deep wounds are less likely to benefit from MDT. Septic arthritis does not seem to be a good indication for MDT.

Comparison of four systems of classification of diabetic foot ulcers in Tanzania

AIMS

The aim was to compare the use of four different systems of foot ulcer classification in a consecutive population with diabetes presenting to a specialist clinic in Dar es Salaam, Tanzania.

METHODS

Clinical data were collected prospectively in all patients presenting with foot ulcers between 3 January 2003 and 30 September 2005, and were used retrospectively to classify their ulcers using the Meggitt/Wagner, University of Texas (UT), Size (Area and Depth), Sepsis, Arteriopathy, and Denervation [S(AD)SAD] and Perfusion, Extent/size, Depth/tissue loss, Infection and Sensation (PEDIS) systems. Comparison was made between the strength of the associations between baseline characteristics of each system and outcome determined at 5 December 2005, using linear by linear association.

RESULTS

The strongest statistical associations (P < 0.001) were observed between percent healing and Wagner score (chi(2)= 85.923), depth [S(AD)SAD, PEDIS and UT grade, 70.558], infection [S(AD)SAD, 61.774; PEDIS, 37.924] and UT stage (32.929). Weaker but significant (P < 0.001) associations were observed between percent healing and neuropathy [S(AD)SAD, PEDIS 12.475] and peripheral arterial disease [S(AD)SAD, PEDIS 10.799], as well as cross-sectional area [S(AD)SAD 4.387, P = 0.036].

CONCLUSION

The strength of the statistical association between outcome and both neuropathy and infection contrasts with findings in series previously reported from the USA and UK, and highlights the differences which may be found in different populations. These differences have implications for any system of classification chosen to compare the effectiveness of management in different centres in different countries.

Temporal characteristics of plantar shear distribution: relevance to diabetic patients

Diabetic foot ulcers are known to have a biomechanical etiology. Among the mechanical factors that cause foot lesions, shear stresses have been either neglected or underestimated. The purpose of this study was to determine various plantar pressure and shear variables in the diabetic and control groups and compare them. Fifteen diabetic patients with neuropathy and 20 non-diabetic subjects without foot symptoms were recruited. Subjects walked on a custom-built platform capable of measuring local normal and tangential forces simultaneously. Pressure-time integral quantities were increased by 54% (p=0.013) in the diabetic group. Peak AP and resultant shear magnitudes were found to be about 32% larger (p<0.05), even though diabetic subjects walked at a slower velocity. Lower AP and ML stress range (peak-to-peak) values were observed in the control subjects (p<0.05). Shear-time integral values were increased in the diabetic group by 61% and 132% for AP and resultant shear cases, respectively (p<0.05). Plantar shear is known to be a factor in callus formation and has previously been associated with higher ulcer incidence. During gait, shear stresses are induced with twice the frequency of pressure characteristically. Therefore, plantar shear should be investigated further from a broader perspective including the temporal specifications and fatigue failure characteristics of the affected plantar tissue.

Diabetic foot disease in the elderly

Elderly diabetic patients are particularly burdened by foot disease. The main causes for foot disease are peripheral neuropathy, foot deformities and peripheral arterial disease (PAD). Other risk factors include poor vision, gait abnormalities, reduced mobility an medical co-morbidities. The risk of major amputations increases with age, along with the increased prevalence of these risk factors. Th true risk of amputation and other burdens of foot disease in the elderly are likely underestimated by current epidemiological data. Th prevalence of neuropathy, foot deformities and PAD as well as the risk of amputation all increase with age even in non-diabetic patients. The principles of prevention and management of diabetic foot disease may also apply to large segments of the elderly non-diabetic population. Foot ulcer prevention relies on the identification of high risk patients and avoidance of triggering events, such as ill-fitting shoes, walking barefoot or poor self-care. PAD is a major cause of amputation and should be prevented by lifelong attention to glycaemic control, treatment of hypertension and dyslipidemia, and avoidance of smoking. The treatment of foot ulcers relies on pressure relief (off-loading), wound debridement, and treatment of infection and ischemia. It requires an individualized approach considering the patient's co-morbidities and functional status. Off-loading remains essential, but devices such as total contact casts or crutches can only rarely be implemented. However, providing adapted standard foot-wear and insisting on its consistent use even at home is often effective. The benefits of aggressive vascular or orthopaedic surgery should be weighed against the risks of prolonged hospitalisation and resulting functional decline. Greater attention to prevention and individualized care are needed to reduce the burden of diabetic foot disease in the elderly.

The association between baseline characteristics and the outcome of foot lesions in a UK population with diabetes

AIMS

To explore the relationships between time to healing of diabetic foot ulcers and baseline characteristics of both patients and their ulcers.

METHODS

All patients were included who were referred to a specialist clinic over a 4-year period. Age, gender, type and duration of diabetes, ulcer site, ulcer duration and baseline characteristics were recorded. Postcode was used to derive an index of social deprivation. Patients were followed up to 1 year. The primary outcome measure was time to healing. Those who died or had an ulcer-related amputation were censored at the time of death or amputation and classified as unhealed.

RESULTS

Mean age of 449 participants (63.7% male) was 66.7 years; 42.7% had evidence of peripheral arterial disease, and 80% had peripheral neuropathy. Median ulcer duration at presentation was 29 days; 60.5% ulcers had an area of < 1 cm(2) and 68.3% of all ulcers healed without amputation during the follow-up period. Univariate analysis revealed dose-response relationships between time to healing and increasing duration of diabetes, increasing ulcer area, ulcer site and peripheral arterial disease. No associations were found with age, gender, diabetes type, deprivation index, peripheral neuropathy or infection. The relationship between healing time and ulcer area, peripheral arterial disease and diabetes duration remained significant on multivariate analysis.

CONCLUSIONS

The dominant factors influencing healing are cross-sectional area at presentation and the degree of peripheral arterial disease. Further work is needed to define how those at greatest risk may be identified and best managed.

Scottish foot ulcer risk score predicts foot ulcer healing in a regional specialist foot clinic

OBJECTIVE

To determine whether patients developing ulcers had previously been identified as being at high risk of ulceration using the Scottish Care Information-Diabetes Collaboration (SCI-DC) ulcer risk score and whether the risk score predicts ulcer healing.

RESEARCH DESIGN AND METHODS

All patients attending the diabetes foot clinic with an ulcer had been assessed for foot ulcer risk using the SCI-DC risk calculator, which categorizes patients into low, moderate, or high risk of ulceration. Information on foot pulses, neuropathy, foot deformity, previous ulcer, ulcer site, depth, and presence of sepsis was recorded and related to ulcer outcome. Patients were followed up until outcome was achieved (median 3 months [range 1-33]).

RESULTS

Of patients attending the clinic with a foot ulcer (mean [+/-SD] age 67.3 +/- 12.7 years, 68% male), 68% were previously recognized to be at high risk of foot ulceration, and 98% were high or moderate risk. Of 221 ulcers, the healing rate was 75% overall but was lower for high-risk patients compared with other patients (68 vs. 93%; P < 0.0001). Of the remainder, 3% became chronic ulcers, 12% required minor or major amputation, and 10% died with their ulcer. In multivariate analysis, absent pulses, neuropathy, increased age, and deep ulcers were associated with poor healing. The combination of neuropathy and ischemia was particularly associated with poor outcome of an ulcer (61% healing).

CONCLUSIONS

The Scottish foot ulcer risk score predicts both ulcer development and ulcer healing. The risk score can be a useful initial guide to determine the likelihood of poor healing. The individual criteria contributing to this overall risk are similar to other studies.

Health-related quality of life among patients with diabetes and foot ulcers: association with demographic and clinical characteristics

OBJECTIVE

The purpose of the study was to describe the sociodemographic variables, clinical characteristics, and treatment factors in patients with diabetic foot ulcers (DFU) and to explore the associations between these factors and the patients' health-related quality of life (HRQL).

MATERIALS AND METHODS

Cross-sectional data were obtained from 127 patients consecutively recruited from six hospital outpatient clinics. The patients were over 20 years of age, had current DFU, and had been diagnosed with diabetes of either Type 1 or Type 2. Data were obtained by clinical and laboratory examination and by self-completed questionnaires (SF-36). Descriptive analyses, bivariate analyses, and hierarchical regression analyses in three blocks were performed.

RESULTS

The patients' mean age was 60 years (S.D., 13.8 years); 72% were men, and 29% had Type 1 diabetes. The most important variables explaining the variance in HRQL were the presence of biochemical signs of inflammation as measured by the detection of C-reactive protein (CRP) >10 mg/l, an ankle-brachial index (ABI) <0.9, an ulcer size > or =5 cm(2), nephropathy, and a body mass index <25 kg/m(2). The strongest association occurred between biochemical signs of inflammation CRP >10 mg/l, ABI <0.9, ulcer size >5 cm(2), and HRQL on physical functioning (adjusted r(2)=24). A major part of the variance remained unexplained and should be investigated in future studies.

CONCLUSION

The findings may tend to identify the most vulnerable subgroups among those with DFU and may be useful in the formulation of strategies to improve function and HRQL in these patients.

Plantar shear stress distributions: comparing actual and predicted frictional forces at the foot-ground interface

Plantar shear stresses are believed to play a major role in diabetic ulceration. Due to the lack of commercial devices that can measure plantar shear distribution, a number of mathematical models have been developed to predict plantar frictional forces. This study assessed the accuracy of these models using a custom-built platform capable of measuring plantar stresses simultaneously. A total of 48 (38 healthy and 10 diabetic) human subjects (75+/-20 kg, 41+/-20 years, 32 males, 16 females) were recruited in the study. Plantar force data were collected for 2s at 50 Hz. Two models (M1 and M2) reported in the literature by different groups were used to predict local shear stresses. Root mean squared errors (RMSE) were calculated to compare model data with the actual data, focusing on three parameters: location, magnitude and timing of peak shear components. RMSE values of estimated peak AP and ML shear locations were 3.1 and 2.2 cm for M1 and 3.1 and 2.1cm for M2, respectively. Magnitude RMS error values for M1 were found to be 86.6 kPa in AP shear and 38.5 kPa in ML shear, whereas these values were determined to be 97.8 and 63.5 kPa, respectively by M2. Time to peak shear RMSE values averaged 17.2% in terms of the gait duration. In conclusion, distribution of plantar shear should be measured rather than predicted, particularly if one is interested in the magnitudes of shear components.

Optimal organization of health care in diabetic foot disease: introduction to the Eurodiale study

This article describes the rationale and protocol of a large data collection study in patients with new diabetic foot ulcers by the Eurodiale study group, a consortium of centers of expertise in the field of diabetic foot disease within Europe. This study is a multicenter, observational, prospective data collection study. Its main aim is to determine the major factors determining clinical outcome and outcome in terms of health-related quality of life and health care consumption. Between September 1, 2003, and October 1, 2004, in 14 European centers, all consecutive patients with diabetes and a new foot ulcer were included in the study and followed until the end point or for a maximum of 1 year. End points were healing of the foot, major amputation, or death. Data were collected on patient, foot, and ulcer characteristics and on diagnostic and management procedures. Furthermore, data were collected on health care organization, quality of life, and resource use. A total of 1232 patients were included in the study. Sixty-three percent of the patients were referred by their general practitioner or were self-referrals. Twenty-seven percent of the patients were admitted at the time of inclusion; 1088 patients were followed until the end point. "Optimal Organization of Health Care in Diabetic Foot Disease" is one of the first large multicenter studies in the field of diabetic foot disease on clinical presentation, clinical outcome, quality of life, resource utilization, and health care organization and their interrelationships. These data will provide us with new insights that enable us to improve care for these patients and guide the development of new studies in this area. The results of this study are the subject of a separate presentation.

Peripheral neuropathy in patients with diabetic foot ulcers: clinical and nerve conduction study

OBJECTIVES

Diabetic foot lesions develop predominantly in male patients and sensory neuropathy is the most frequent type of neuropathy associated with these lesions. The aim of this study was to analyze the clinical and electrophysiological features in a cohort of patients with diabetic foot.

RESEARCH DESIGN AND METHODS

The recordings of 318 consecutive diabetic patients (127 women and 191 men) with an ongoing or healed foot ulcer who had been referred for electrophysiological consultation were evaluated retrospectively.

RESULTS

60.1% of our cohort were male. Loss of deep sensation and deep tendon reflex abnormalities were the most common neurological findings. Negative sensory symptoms (63.7% vs 40.8%, p<0.01) and neuropathic pain (38.5% vs 18.3%, p<0.01) were more frequent in females, whereas atrophy was more frequent in male patients (22.8% vs 46%, p<0.01). Motor nerve conduction abnormalities and ulnar nerve involvement was more frequent and severe in males. Abnormal electrophysiological findings were mild in 70 patients (female 42, 60%). In this group, hemiplegia, peripheral arterial disease, multiple bone fractures, end stage renal failure, recent pulmonary tuberculosis and dementia accompanied mild polyneuropathy. Thirty patients had shown prominent decrease in nerve conduction velocity which indicated severe demyelination. Among these 30 patients, 6 male subjects had clinical features similar to that of chronic inflammatory demyelinating polyneuropathy.

CONCLUSIONS

Our results indicate that male gender, motor neuropathy and mononeuropathies, especially ulnar neuropathy is associated with the development of DF among our patients with DF. Patients with diabetes mellitus have a predisposition to develop chronic inflammatory demyelinating polyneuropathy and this may also facilitate formation of diabetic foot. History of hemiplegia, dementia and trauma are permissive risk factors for diabetic foot in the presence of mild polyneuropathy.

High prevalence of ischaemia, infection and serious comorbidity in patients with diabetic foot disease in Europe. Baseline results from the Eurodiale study

AIMS/HYPOTHESIS

Large clinical studies describing the typical clinical presentation of diabetic foot ulcers are limited and most studies were performed in single centres with the possibility of selection of specific subgroups. The aim of this study was to investigate the characteristics of diabetic patients with a foot ulcer in 14 European hospitals in ten countries.

METHODS

The study population included 1,229 consecutive patients presenting with a new foot ulcer between 1 September 2003 and 1 October 2004. Standardised data on patient characteristics, as well as foot and ulcer characteristics, were obtained. Foot disease was categorised into four stages according to the presence or absence of peripheral arterial disease (PAD) and infection: A: PAD -, infection -; B: PAD -, infection +; C: PAD +, infection -; D: PAD +, infection +.

RESULTS

PAD was diagnosed in 49% of the subjects, infection in 58%. The majority of ulcers (52%) were located on the non-plantar surface of the foot. With regard to severity, 24% had stage A, 27% had stage B, 18% had stage C and 31% had stage D foot disease. Patients in the latter group had a distinct profile: they were older, had more non-plantar ulcers, greater tissue loss and more serious comorbidity.

CONCLUSIONS/INTERPRETATION

According to our results in this European cohort, the severity of diabetic foot ulcers at presentation is greater than previously reported, as one-third had both PAD and infection. Non-plantar foot ulcers were more common than plantar ulcers, especially in patients with severe disease, and serious comorbidity increased significantly with increasing severity of foot disease. Further research is needed to obtain insight into the clinical outcome of these patients.

Prediction and monitoring the therapeutic response of chronic dermal wounds

A significant proportion of chronic wounds fail to heal in response to treatment of underlying pathologies combined with good wound care practice. Current prognostic tests to identify these wounds rely on the use of algorithms based on clinically measurable parameters such as wound dimensions and wound duration. Venous leg ulcers may be stratified into healing/non healing at 24 weeks of compression therapy and diabetic foot ulcer treatment outcome assessed using a 3-parameter algorithm. Accurate and reproducible measurement of wound area is required for these algorithms to have clinical utility. Whilst a number of attempts have been made to develop computerised wound-assessment techniques, wound tracing by clinicians combined with planimetry remains the standard methodology. Once treatment has been initiated, it is important to continuously monitor the wound to assess efficacy of treatment. This can be achieved by measuring wound area change over the first weeks of treatment to identify whether re-assessment of treatment strategy is required. A number of algorithms for assessing rate of wound area change have been evaluated to determine a surrogate endpoint for healing. Retrospective analysis of large patient groups indicates that approximately 75% correct prediction of healing outcome can be achieved.

The incidence and risks of failure to heal after lower extremity amputation for the treatment of diabetic neuropathic foot ulcer

The primary goal of this retrospective cohort study was to determine the incidence of failure to heal after lower extremity amputation for the treatment of diabetic neuropathic foot ulcer, and the secondary goal was to identify risk factors associated with the outcome. We evaluated 1775 patients who underwent amputation for the treatment of 5314 neuropathic foot ulcers, and who were treated in a network of wound care centers. We calculated the incidence of failure to heal after the initial amputation, and used generalized estimation equations and generalized linear latent and mixed model regression to evaluate the association of failure to heal by the 20th week of care. The unadjusted incidence of failure to heal was 34.01%, and male sex, number of wounds, wound grade, and adjunct therapy were all significantly associated with failure to heal. With the exception of wound grade, the associations were not significantly affected by the treating wound care center, and a sensitivity analysis showed the results to be resistant to the theoretical influence of an unmeasured potential confounder. These findings should be useful to clinicians treating diabetic neuropathic foot ulcers, and should aid surgeons in the determination of the most appropriate level for lower extremity amputation.

What is the best method for assessing the rate of wound healing? A comparison of 3 mathematical formulas

OBJECTIVE

To identify and evaluate current mathematical formulas used to assess the rate of wound healing.

DATA SOURCES

MEDLINE, CINAHL, and Cochrane Systematic Review databases, from 1965 to 2004.

STUDY SELECTION

Papers selected for the study met the following inclusion criteria: (1) participants had chronic venous, neuropathic, pressure, or ischemic wounds; (2) the wounds were objectively measured; and (3) the investigators described and used an objective measurement of wound healing rate, either as an absolute reduction in area over time, a percentage change, or a linear advancement of wound edge. Papers were excluded if they were (1) not written in English, (2) duplicated from other sources, or (3) unpublished.

CONCLUSIONS

In clinical trials, measurement of the rate of wound healing over time by using the equation for the linear advancement of wound margins toward the center of the wound controls for confounding introduced by differing baseline ulcer sizes and shapes. Use of this assessment method after 4 weeks of healing may prove to be of value in predicting time to complete healing. Further research is required to develop standard healing rates for wounds of different etiologies.

F. Fatores predisponentes para amputação de membro inferior em pacientes diabéticos internados com pés ulcerados no estado de Sergipe

OBJETIVO: Determinar os fatores predisponentes para a amputação de membros inferiores nos doentes internados com diabetes melito e úlceras nos pés. MÉTODOS: Foram acompanhados os pacientes diabéticos com úlceras nos pés internados no período de 6 meses e analisadas as amputações nesses doentes em relação à idade, sexo, amputação prévia, número de ulcerações, tempo de diagnóstico do diabete, tempo de ulceração, tempo médio de internação, gravidade das lesões, presença de pulso. RESULTADOS: Verificou-se que 55% (44/80) dos doentes evoluíram para algum tipo de amputação de membros inferiores; a mediana das idades foi de 61 anos, porém a ocorrência de amputação foi significativamente maior na faixa etária dos 60 aos 90 anos (P = 0,03). Não se observou uma variação significativa da mediana do tempo de diagnóstico do diabetes, do tempo de ulceração e do tempo médio de internação em relação ao grupo de pacientes que foram amputados. Entretanto, as lesões mais graves, quando avaliadas pela classificação de Wagner (P <0,001) e pela ausência de detecção dos dois pulsos distais (P <0,001) dos membros inferiores, revelaram-se bastante significativas com relação ao desfecho de amputação. CONCLUSÃO: Foram considerados fatores predisponentes para a ocorrência de amputação nesses doentes a gravidade das lesões, a ausência de pulsos e as idades acima de 60 anos.

The Prevalence and Occurrence of Diabetic Foot Ulcer Pain and Its Impact on Health-Related Quality of Life

This study describes the prevalence and occurrence of diabetic foot ulcer (DFU) pain and the impact of DFU pain on health-related quality of life (HRQL) using generic and disease specific instruments. Data were obtained from 127 patients with DFU who were recruited from 6 hospital-based diabetic outpatient clinics. HRQL was measured using the Medical Outcome Study-Short Form (SF-36) and the Diabetes Foot Ulcer Scale (DFS). Occurrence of pain was assessed using 2 items from the DFS (ie, pain while walking and/or standing and pain during the night related to foot ulcer problems). Seventy-five percent reported some pain related to DFU and 57% reported DFU pain while walking and/or standing and also during the night. Twenty-five percent reported pain none of the time. A higher percentage of patients with pain reported having a prescription for an analgesic medication than those without pain. Patients who reported pain most or all of the time had statistically and clinically significantly poorer HRQL than those who did not report pain. These findings suggest that pain associated with DFU is a significant clinical problem. Additional research is warranted to further characterize the pain associated with DFU and its impact on patient outcomes and HRQL.

PERSPECTIVE

Numerous basic and clinical studies have focused on pain associated with diabetic peripheral neuropathy. Findings from this study suggest a new pain problem in patients with diabetes, namely, pain associated with foot ulcers, that warrants further investigation.

Silver based wound dressings and topical agents for treating diabetic foot ulcers

BACKGROUND

Foot ulceration affects 15-20% of people with diabetes. It is a major precursor to amputation in this patient group, and early and appropriate treatment provides the greatest opportunity for healing. The use of silver for its antimicrobial properties has re-emerged, and modern wound dressings that release a sustained amount of free silver ions, are now widely used in wound management.

OBJECTIVES

To evaluate the effects of silver-containing dressings and topical agents on infection rates and healing of diabetes related foot ulcers.

SEARCH STRATEGY

Searches were made of the Cochrane Wounds Group Specialised Register (August 2005), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library Issue 3 2005) MEDLINE (1966 to October week 2 2004), EMBASE (1980 to October week 2 2004) and CINAHL (1982 to October week 2 2004). The Journal of Wound Care (Volume 12/13 Issues 1-10) was hand-searched. Manufacturers, researchers and local and international wound groups were contacted in order to identify unpublished trials. Web sites for wound groups and World Wide Wounds (www.worldwidewounds.com) were searched.

SELECTION CRITERIA

Randomised controlled trials and non-randomised controlled clinical trials were considered for inclusion. Studies were included if they involved participants with Type 1 or Type 2 diabetes and related foot ulcers, met the requirements for randomisation, allocation and concealment where appropriate, and compared the intervention with a placebo or a sham dressing, an alternative non silver based dressing or no dressing, and reported outcomes that represent healing rate or infection.

DATA COLLECTION AND ANALYSIS

Two authors independently evaluated the papers identified by the search strategy against the inclusion criteria but identified no trials eligible for inclusion in the review. It was not possible to perform planned subgroup and sensitivity analysis in the absence of data. In future, if eligible trials become available, a random effects model will be applied for meta-analysis in the presence of statistical heterogeneity (estimated using the I(2) statistic). Dichotomous outcomes will be reported as risk ratios with 95% confidence intervals (CI), and continuous outcomes as weighted mean differences (WMD) with 95% CI. Statistical significance will be set at P value < 0.05 for all outcomes and the magnitude of the effect will be estimated by calculating the number needed to treat (NNT) with 95% CI.

MAIN RESULTS

No studies were identified that met with the inclusion criteria

AUTHORS' CONCLUSIONS

Despite the widespread use of dressings and topical agents containing silver for the treatment of diabetic foot ulcers, no randomised trials or controlled clinical trials exist that evaluate their clinical effectiveness. Trials are needed to determine clinical and cost-effectiveness and long term outcomes including adverse events.