Randomized Controlled Trial Comparing the Effects of Far-Infrared Emitting Ceramic Fabric Shirts and Control Polyester Shirts on Transcutaneous PO2.

Our aim was to confirm earlier studies showing tcPO2 to be higher under clothing made with polyethylene terephalate (PET) fabric containing ceramic particles (CEL) compared to standard PET fabric. In previous studies PET garments were donned first to avoid possible persistent effects from ceramic particles. This study randomized donning sequence to avoid bias. METHODS: Subjects were randomized to don either PET shirts first (PETF n=73) or CEL first (CELF n=80), switching garments after 90 minutes. Skin temperature (ST), arterial oxygen saturation (O2sat), and tcPO2 were measured every 30 minutes. RESULTS: Baseline ST and O2 sat were nearly identical in the two groups. Baseline tcPO2 was modestly higher in the CELF group than with PETF: 66.4 ± 18.9 vs. 63.9 ± 18.8 mmHg (n.s). Independent of donning sequence, tcPO2 measurements 90 minutes after wearing CEL were 6.7% higher than after 90 minutes wearing PET (p<0.0003). Sequence analysis found tcPO2 in PETF subjects to gradually rise before and after switching garments, but tcPO2 fell immediately after switching garments in CELF subjects. PETF baseline O2sat of 98.1 ± 1.3 increased insignificantly after 90 minutes, and then increased further to 98.6 ± 0.8 after wearing CEL ninety minutes (p=0.0001). CELF baseline O2sat of 97.9 ± 1.7 increased to 98.5 ± 1.1 90 minutes after donning CEL (p=0.0002) and fell to 98.3 ± 1.0 ninety minutes after switching to PET (p=0.0033). CONCLUSIONS: The ability of ceramic-embedded fabric to induce higher tcPO2 measurements is not due to sequence bias.

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

BACKGROUND: Prevention of foot ulcers in patients with diabetes is extremely important to help reduce the enormous burden of foot ulceration on both patient and health resources. A comprehensive analysis of reported interventions is not currently available, but is needed to better inform caregivers about effective prevention. The aim of this systematic review is to investigate the effectiveness of interventions to prevent first and recurrent foot ulcers in persons with diabetes who are at risk for ulceration. METHODS: The available medical scientific literature in PubMed, EMBASE, CINAHL and the Cochrane database was searched for original research studies on preventative interventions. Both controlled and non-controlled studies were selected. Data from controlled studies were assessed for methodological quality by two independent reviewers. RESULTS: From the identified records, a total of 30 controlled studies (of which 19 RCTs) and another 44 non-controlled studies were assessed and described. Few controlled studies, of generally low to moderate quality, were identified on the prevention of a first foot ulcer. For the prevention of recurrent plantar foot ulcers, multiple RCTs with low risk of bias show the benefit for the use of daily foot skin temperature measurements and consequent preventative actions, as well as for therapeutic footwear that demonstrates to relieve plantar pressure and that is worn by the patient. To prevent recurrence, some evidence exists for integrated foot care when it includes a combination of professional foot treatment, therapeutic footwear and patient education; for just a single session of patient education, no evidence exists. Surgical interventions can be effective in selected patients, but the evidence base is small. CONCLUSION: The evidence base to support the use of specific self-management and footwear interventions for the prevention of recurrent plantar foot ulcers is quite strong, but is small for the use of other, sometimes widely applied, interventions and is practically nonexistent for the prevention of a first foot ulcer and non-plantar foot ulcer.

Interventions in the management of infection in the foot in diabetes: a systematic review.

The expert panel on diabetic foot infection (DFI) of the International Working Group on the Diabetic Foot conducted a systematic review seeking all published reports relating to any type of treatment for infection of the foot in persons with diabetes published as of 30 June 2014. This review, conducted with both PubMed and EMBASE, was used to update an earlier one undertaken on 30 June 2010 using the same search string. Eligible publications included those that had outcome measures reported for both a treated and a control population that were managed either at the same time, or as part of a before-and-after case design. We did not include studies that contained only information related to definition or diagnosis, but not treatment, of DFI. The current search identified just seven new articles meeting our criteria that were published since the 33 identified with the previous search, making a total of 40 articles from the world literature. The identified articles included 37 randomised controlled trials (RCTs) and three cohort studies with concurrent controls, and included studies on the use of surgical procedures, topical antiseptics, negative pressure wound therapy and hyperbaric oxygen. Among the studies were 15 RCTs that compared outcomes of treatment with new antibiotic preparations compared with a conventional therapy in the management of skin and soft tissue infection. In addition, 10 RCTs and 1 cohort study compared different treatments for osteomyelitis in the diabetic foot. Results of comparisons of different antibiotic regimens generally demonstrated that newly introduced antibiotic regimens appeared to be as effective as conventional therapy (and also more cost-effective in one study), but one study failed to demonstrate non-inferiority of a new antibiotic compared with that of a standard agent. Overall, the available literature was both limited in both the number of studies and the quality of their design. Thus, our systematic review revealed little evidence upon which to make recommendations for treatment of DFIs. There is a great need for further well-designed trials that will provide robust data upon which to make decisions about the most appropriate treatment of both skin and soft tissue infection and osteomyelitis in diabetic patients.

The microbiome of diabetic foot osteomyelitis.

The purpose of this investigation was to evaluate the diversity of bacteria in diabetic foot osteomyelitis using a 16S rRNA sequencing approach and to compare the results with conventional culture techniques. In this prospective observational study, we obtained 34 bone samples from patients admitted to our hospital with a moderate-severe diabetic foot infection. We analysed the distribution of the 16S rRNA gene sequences in the bone samples, using an Illumina MiSeq Personal Sequencer. We compared the genera that were detected with the cultured pathogens in the bone samples with conventional techniques. In the 23 samples that had positive results with both techniques, Staphylococcus, Corynebacterium, Streptococcus and Propionibacterium spp. were detected in 20, 18, 13 and 11 samples, respectively. Significantly more anaerobes were detected with 16S rRNA sequencing compared to conventional techniques (86.9 % vs. 23.1 %, p = 0.001) and more Gram-positive bacilli were present (78.3 % vs. 3.8 %, p < 0.001). Staphylococcus spp. were identified in all of the sequenced bone samples that were negative with conventional techniques. Mixed genera were present in 83.3 % (5 of 6) of the negative samples. Anaerobic and fastidious organisms may play a more significant role in osteomyelitis than previously reported. Further studies with larger populations are needed in order to fully understand the clinical importance of the microbial diversity of diabetic foot osteomyelitis.

A systematic review of the effectiveness of interventions in the management of infection in the diabetic foot.

The International Working Group on the Diabetic Foot expert panel on infection conducted a systematic review of the published evidence relating to treatment of foot infection in diabetes. Our search of the literature published prior to August 2010 identified 7517 articles, 29 of which fulfilled predefined criteria for detailed data extraction. Four additional eligible papers were identified from other sources. Of the total of 33 studies, 29 were randomized controlled trials, and four were cohort studies. Among 12 studies comparing different antibiotic regimens in the management of skin and soft-tissue infection, none reported a better response with any particular regimen. Of seven studies that compared antibiotic regimens in patients with infection involving both soft tissue and bone, one reported a better clinical outcome in those treated with cefoxitin compared with ampicillin/sulbactam, but the others reported no differences between treatment regimens. In two health economic analyses, there was a small saving using one regimen versus another. No published data support the superiority of any particular route of delivery of systemic antibiotics or clarify the optimal duration of antibiotic therapy in either soft-tissue infection or osteomyelitis. In one non-randomized cohort study, the outcome of treatment of osteomyelitis was better when the antibiotic choice was based on culture of bone specimens as opposed to wound swabs, but this study was not randomized, and the results may have been affected by confounding factors. Results from two studies suggested that early surgical intervention was associated with a significant reduction in major amputation, but the methodological quality of both was low. In two studies, the use of superoxidized water was associated with a better outcome than soap or povidone iodine, but both had a high risk of bias. Studies using granulocyte-colony stimulating factor reported mixed results. There was no improvement in infection outcomes associated with hyperbaric oxygen therapy. No benefit has been reported with any other intervention, and, overall, there are currently no trial data to justify the adoption of any particular therapeutic approach in diabetic patients with infection of either soft tissue or bone of the foot.

Expert opinion on the management of infections in the diabetic foot.

This update of the International Working Group on the Diabetic Foot incorporates some information from a related review of diabetic foot osteomyelitis (DFO) and a systematic review of the management of infection of the diabetic foot. The pathophysiology of these infections is now well understood, and there is a validated system for classifying the severity of infections based on their clinical findings. Diagnosing osteomyelitis remains difficult, but several recent publications have clarified the role of clinical, laboratory and imaging tests. Magnetic resonance imaging has emerged as the most accurate means of diagnosing bone infection, but bone biopsy for culture and histopathology remains the criterion standard. Determining the organisms responsible for a diabetic foot infection via culture of appropriately collected tissue specimens enables clinicians to make optimal antibiotic choices based on culture and sensitivity results. In addition to culture-directed antibiotic therapy, most infections require some surgical intervention, ranging from minor debridement to major resection, amputation or revascularization. Clinicians must also provide proper wound care to ensure healing of the wound. Various adjunctive therapies may benefit some patients, but the data supporting them are weak. If properly treated, most diabetic foot infections can be cured. Providers practising in developing countries, and their patients, face especially challenging situations.

Functional status of persons with diabetes-related lower-extremity amputations.

OBJECTIVE: It is reasonable to predict that diabetes-related lower-extremity amputations have a detrimental impact on quality of life. However, we are unaware of any study in the medical literature describing the functional level of diabetic patients with amputations. The objective of this study was to evaluate amputations among diabetic patients and to determine the functional level of these patients with the Sickness Impact Profile (SIP). RESEARCH DESIGN AND METHODS: We enrolled 124 patients with diabetes. Case subjects (n = 35) were defined as patients who had undergone amputation of the lower-extremity, and control subjects (n = 89) were defined as patients who had not undergone amputation. Study participants received a standard history and physical examination. RESULTS: Both the physical dimension scores (33.5 +/- 14.9 vs. 22.3 +/- 14.7, P < 0.001) and the total SIP scores (27.6 +/- 9.9 vs. 22.5 +/- 10.3, P = 0.013) were significantly higher for amputees. However, the psychosocial dimension scores were not significantly different between case and control subjects (14.9 +/- 8.9 vs. 15.2 +/- 10.0, P > 0.05). Post hoc analysis showed that the group of patients who had undergone transtibial amputation had a significantly higher total impairment score than patients who had not undergone amputation (P = 0.039). This is in contrast to patients with toe or midfoot amputations, for whom total impairment scores were not significantly higher than those for the control subjects. Interestingly, bilateral amputees did not have significantly higher scores on either SIP dimension compared with unilateral amputees. CONCLUSIONS: These findings exemplify the detrimental physical and psychosocial health status of patients with diabetes-related lower-extremity amputation.

Effectiveness of the diabetic foot risk classification system of the International Working Group on the Diabetic Foot.

OBJECTIVE: To evaluate the effectiveness of a diabetic foot risk classification system by the International Working Group on the Diabetic Foot to predict clinical outcomes. RESEARCH DESIGN AND METHODS: A total of 225 diabetic patients were initially evaluated as part of a prospective case-control study at the University of Texas Health Science Center at San Antonio. Complete records were available for 213 patients for follow-up evaluation after 29 months. Upon enrollment, subjects were stratified into four risk groups based on the presence of risk factors according to the consensus of the International Working Group on the Diabetic Foot. Group 0 consisted of subjects without neuropathy, group 1 consisted of patients with neuropathy but without deformity or peripheral vascular disease (PVD), group 2 consisted of subjects with neuropathy and deformity or PVD, and group 3 consisted of patients with a history of foot ulceration or a lower-extremity amputation. RESULTS: Upon enrollment, patients in higher-risk groups had longer duration of diabetes, worse glycemic control, vascular and neuropathic variables, and more systemic complications of diabetes. During 3 years of follow-up, ulceration occurred in 5.1, 14.3, 18.8, and 55.8% of the patients in groups 0, 1, 2, and 3, respectively (linear-by-linear association, P < 0.001). All amputations were found in Groups 2 and 3 (3.1 and 20.9%, P < 0.001). CONCLUSIONS: The foot risk classification of the International Working Group on the Diabetic Foot predicts ulceration and amputation and can function as a tool to prevent lower-extremity complications of diabetes.

Electric stimulation as an adjunct to heal diabetic foot ulcers: a randomized clinical trial.

OBJECTIVE: To evaluate high-voltage, pulse-galvanic electric stimulation as an adjunct to healing diabetic foot ulcers. DESIGN: Randomized, double-blind, placebo-controlled pilot trial. SETTING: University medical center. PATIENTS: Forty patients with diabetic foot ulcers, consecutively sampled. Twenty patients each assigned to treatment and placebo groups. Five patients (2 treated, 3 placebo) withdrew because of severe infection. INTERVENTIONS: Electric stimulation through a microcomputer every night for 8 hours. The placebo group used identical functioning units that delivered no current. Additional wound care consisted of weekly débridements, topical hydrogel, and off-loading with removable cast walkers. Patients were followed for 12 weeks or until healing, whichever occurred first. MAIN OUTCOME MEASURES: Proportion of wounds that healed during the study period. Compliance with use of device (in hr/wk), rate of wound healing, and time until healing. RESULTS: Sixty-five percent of the patients healed in the group treated with stimulation, whereas 35% healed with placebo (p = .058). After stratification by compliance, a significant difference was identified among compliant patients in the treatment group (71% healed), noncompliant patients in the treatment group (50% healed), compliant patients in the placebo group (39% healed), and noncompliant patients in the placebo group (29% healed, linear-by-linear association = 4.32, p = .038). There was no significant difference in compliance between the 2 groups. CONCLUSION: Electric simulation enhances wound healing when used in conjunction with appropriate off-loading and local wound care.

Off-loading the diabetic foot wound: a randomized clinical trial.

OBJECTIVE: To compare the effectiveness of total-contact casts (TCCs), removable cast walkers (RCWs), and half-shoes to heal neuropathic foot ulcerations in individuals with diabetes. RESEARCH DESIGN AND METHODS: In this prospective clinical trial, 63 patients with superficial noninfected, nonischemic diabetic plantar foot ulcers were randomized to one of three off-loading modalities: TCC, half-shoe, or RCW. Outcomes were assessed at wound healing or at 12 weeks, whichever came first. Primary outcome measures included proportion of complete wound healing at 12 weeks and activity (defined as steps per day). RESULTS: The proportions of healing for patients treated with TCC, RCW, and half-shoe were 89.5, 65.0, and 58.3%, respectively. A significantly higher proportion of patients were healed by 12 weeks in the TCC group when compared with the two other modalities (89.5 vs. 61.4%, P = 0.026, odds ratio 5.4, 95% CI 1.1-26.1). There was also a significant difference in survival distribution (time to healing) between patients treated with a TCC and both an RCW (P = 0.033) and half-shoe (P = 0.012). Patients were significantly less active in the TCC (600.1 +/- 320.0 daily steps) compared with the half-shoe (1,461.8 +/- 1,452.3 daily steps, P = 0.04). There was no significant difference in the average number of steps between the TCC and the RCW (767.6 +/- 563.3 daily steps, P = 0.67) or the RCW and the half-shoe (P = 0.15). CONCLUSIONS: The TCC seems to heal a higher proportion of wounds in a shorter amount of time than two other widely used off-loading modalities, the RCW and the half-shoe.

Systemic hyperbaric oxygen therapy: lower-extremity wound healing and the diabetic foot.

OBJECTIVE: To document peer-reviewed medical publications that have reported on hyperbaric oxygen (HBO) therapy as an adjunct to standard lower-extremity wound care, focusing on publications dealing with the diabetic foot. RESEARCH DESIGN AND METHODS: A review of the medical literature was conducted using MEDLINE. Research articles involving HBO treatment and the diabetic foot were critiqued to identify factors that may have been a source of bias. RESULTS: Of the published reports on human studies, seven involved diabetes-related foot pathology. Five of these studies, two of which were randomized, included a control group that did not receive HBO therapy The controlled diabetic foot studies included an average of 28 subjects in the HBO therapy group (range 10-62) and an average of 16.2 subjects in the non-HBO control group (range 5-33). Most of the published reports have several potential sources of bias, including, but not limited to, inadequate evaluation of comorbid conditions relevant to wound healing, small sample size, and poor documentation of wound size or severity. Four of the seven reports involving the diabetic foot were published by a group of researchers at the University of Milan between 1987 and 1996. CONCLUSIONS: Additional randomized placebo-controlled clinical trials in large diabetic populations would further lend credence to the presumption that HBO therapy improves clinical outcomes. Given the relatively high cost of this treatment modality, perhaps a more acute awareness of the medical literature would reduce the economic burden that HBO therapy imposes on care providers that are financially at risk.

Reliability of digital videometry and acetate tracing in measuring the surface area of cutaneous wounds.

PURPOSE: The purpose of this study was to evaluate the reliability of digital videometry and acetate tracing in the measurement of cutaneous wound area. METHODS: Four clinicians used both digital videometry and acetate tracing to measure five wounds that were artificially created on a cadaver specimen. In addition, the clinicians used an analog centimeter ruler to determine a rough estimate of the area of each wound. The wounds were measured a total of five times with each measurement instrument using a non-sequential repeat measures design. Associations between the three wound measurement techniques were examined with Pearson correlation coefficients. In addition, intraclass correlation coefficients (ICC) were calculated for each pair of the three measurement techniques. RESULTS: Correlation between the measurement systems for all raters combined yielded Pearson r-values of 0.93 for ruler and acetate, 0.95 for ruler and digital and 0.97 for acetate and digital. Furthermore, the average measure ICC between acetate and digital was 0.94, between acetate and ruler was 0.76 and between digital and ruler was 0.57. CONCLUSION: These results suggest that wound area measurements obtained using digital videometry and acetate tracing are very similar and both techniques can be used interchangeably in either clinical or research settings.

Effects of diabetes mellitus on the biomechanical properties of human ankle cartilage.

Metabolic changes attributable to diabetes mellitus affect numerous organ systems in the body. For example, patients with diabetes have an increased number of musculoskeletal injuries and afflictions compared with patients without diabetes and experience more morbidity associated with injury and treatment. Although diabetes also may afflict articular cartilage, no studies have shown a conclusive link between diabetes and cartilage structural integrity. The objective of this study was to obtain and compare the intrinsic material properties of human ankle articular cartilage from patients with diabetes and those without diabetes. These biomechanical properties (aggregate modulus, Poisson's ratio, shear modulus, and permeability) were found to differ significantly between specimens from patients with diabetes and patients without diabetes. Specifically, cartilage from patients with diabetes was significantly softer and more permeable than cartilage from control subjects. For example, in the central portion of the talus, cartilage from patients with diabetes had a 38% smaller aggregate modulus, 37% smaller shear modulus, and 111% larger permeability than did tissue from patients without diabetes. These results provide evidence that joint pathologic processes in patients with diabetes may be associated with compromised structural integrity of articular cartilage.

Diabetes-related lower-extremity amputations disproportionately affect Blacks and Mexican Americans.

BACKGROUND: We sought to identify the age-adjusted incidence of lower-extremity amputation (LEA) in Mexican Americans, blacks, and non-Hispanic whites with diabetes in south Texas. METHODS: We summarized medical records for hospitalizations for LEAs for 1993 in six metropolitan statistical areas in south Texas. RESULTS: Age-adjusted incidence per 10,000 patients with diabetes was 146.59 in blacks, 60.68 in non-Hispanic whites, and 94.08 in Mexican Americans. Of the patients, 47% of amputees had a history of amputation, and 17.7% were hospitalized more than once during 1993. Mexican Americans had more diabetes-related amputations (85.9%) than blacks (74.7%) or non-Hispanic whites (56.3%). CONCLUSIONS: This study is the first to identify the incidence of diabetes-related lower-extremity amputations in minorities using primary data. Minorities had both a higher incidence and proportion of diabetes-related, LEAs compared with non-Hispanic whites. Public health initiatives and national strategies, such as Healthy People 2000 and 2010, need to specifically focus on high-risk populations and high-risk geographic areas to decrease the frequency of amputation and reamputation.

Causal pathways for incident lower-extremity ulcers in patients with diabetes from two settings.

OBJECTIVE: To determine the frequency and constellations of anatomic, pathophysiologic, and environmental factors involved in the development of incident diabetic foot ulcers in patients with diabetes and no history of foot ulcers from Manchester, U.K., and Seattle, Washington, research settings. RESEARCH DESIGN AND METHODS: The Rothman model of causation was applied to the diabetic foot ulcer condition. The presence of structural deformities, peripheral neuropathy, ischemia, infection, edema, and callus formation was determined for diabetic individuals with incident foot ulcers in Manchester and Seattle. Demographic, health, diabetes, and ulcer data were ascertained for each patient. A multidisciplinary group of foot specialists blinded to patient identity independently reviewed detailed abstracts to determine component and sufficient causes present and contributing to the development of each patient's foot ulcer. A modified Delphi process assisted the group in reaching consensus on component causes for each patient. Estimates of the proportion of ulcers that could be ascribed to each component cause were computed. RESULTS: From among 92 study patients from Manchester and 56 from Seattle, 32 unique causal pathways were identified. A critical triad (neuropathy, minor foot trauma, foot deformity) was present in > 63% of patient's causal pathways to foot ulcers. The components edema and ischemia contributed to the development of 37 and 35% of foot ulcers, respectively. Callus formation was associated with ulcer development in 30% of the pathways. Two unitary causes of ulcer were identified, with trauma and edema accounting for 6 and < 1% of ulcers, respectively. The majority of the lesions were on the plantar toes, forefoot, and midfoot. CONCLUSIONS: The most frequent component causes for lower-extremity ulcers were trauma, neuropathy, and deformity, which were present in a majority of patients. Clinicians are encouraged to use proven strategies to prevent and decrease the impact of modifiable conditions leading to foot ulcers in patients with diabetes.

The benefit of electrical stimulation to enhance perfusion in persons with diabetes mellitus.

The purpose of this study was to evaluate the effect of galvanic electrical stimulation on vascular perfusion in diabetic patients. Nineteen subjects with diabetes were enrolled. Eleven subjects (57.9%) were diagnosed with impaired peripheral perfusion based upon their initial transcutaneous oximetry values (< 40 mm Hg). The subjects were studied over a 2-day period. On the 1st day, one foot was electrically stimulated for four 60-minute periods by an external electrical stimulation device. Vascular perfusion of both feet was assessed before and after the sessions of electrical stimulation. On the 2nd day, no electrical stimulation was applied and noninvasive vascular measurements were repeated. For the 1st hour, transcutaneous oxygen pressure was measured continuously during stimulation at the lateral aspect of the leg. Subsequently, perfusion between the periods of stimulation was measured on the dorsum of the foot with both transcutaneous oximetry and laser Doppler flowmetry after each stimulation period. In the group with impaired peripheral perfusion, a significant rise in tissue oxygenation as compared to the control measurements was measured during the first 5 minutes of stimulation (p < .040). For those without vascular disease (TcpO2 > 40 mm Hg) however, there was not a significant increase compared to baseline (p = .280). After the periods of stimulation, the stimulated feet did not show any higher perfusion levels than the control feet. Patterns in perfusion during the day, as measured by laser Doppler flowmetry, were similar in the tested feet and in the controls. These data suggest that external subsensory electrical stimulation induces a transient rise in skin perfusion in persons with diabetes and impaired peripheral perfusion.

The effect of increased weight on peak pressures: implications for obesity and diabetic foot pathology.

The purpose of this study was to determine if increased weight contributes to increased mean peak plantar foot pressures when foot function, deformity, and structure are controlled. Ten male and nine female volunteers without sensory neuropathy or other systemic disease were evaluated in the study. Using a repeated measures design, peak plantar foot pressures were compared using the Novel Pedar in-shoe pressure measurement system under three conditions. Baseline measurements were made while volunteers wore the standard test footwear, a thin-soled rubber oxford sneaker. The second and third test conditions involved pressure measurements with an additional 9.1 kg (20 lb) and 18.2 kg (40 lb), respectively, of weight evenly distributed in pockets on the front and back of a workout vest. There was a significant increase in mean peak plantar foot pressures under the metatarsal heads, heel, and midfoot for each incremental increase of weight (baseline vs. 9.1 kg, p < .05; 9.1 kg vs. 18.2 kg, p < .05). The authors conclude that increases in weight increased plantar foot pressures for the first metatarsal, lesser metatarsal, midfoot, and heel regions in both men and women.