Jeff G. van Baal

Effect of Custom-made Footwear on Foot Ulcer Recurrence in Diabetes: A multicenter randomized controlled trial

OBJECTIVE Custom-made footwear is the treatment of choice to prevent foot ulcer recurrence in diabetes. This footwear primarily aims to offload plantar regions at high ulcer risk. However, ulcer recurrence rates are high. We assessed the effect of offloading-improved custom-made footwear and the role of footwear adherence on plantar foot ulcer recurrence. RESEARCH DESIGN AND METHODS We randomly assigned 171 neuropathic diabetic patients with a recently healed plantar foot ulcer to custom-made footwear with improved and subsequently preserved offloading (∼20% peak pressure relief by modifying the footwear) or to usual care (i.e., nonimproved custom-made footwear). Primary outcome was plantar foot ulcer recurrence in 18 months. Secondary outcome was ulcer recurrence in patients with an objectively measured adherence of ≥80% of steps taken. RESULTS On the basis of intention-to-treat, 33 of 85 patients (38.8%) with improved footwear and 38 of 86 patients (44.2%) with usual care had a recurrent ulcer (relative risk −11%, odds ratio 0.80 [95% CI 0.44–1.47], P = 0.48). Ulcer-free survival curves were not significantly different between groups (P = 0.40). In the 79 patients (46% of total group) with high adherence, 9 of 35 (25.7%) with improved footwear and 21 of 44 (47.8%) with usual care had a recurrent ulcer (relative risk −46%, odds ratio 0.38 [0.15–0.99], P = 0.045). CONCLUSIONS Offloading-improved custom-made footwear does not significantly reduce the incidence of plantar foot ulcer recurrence in diabetes compared with custom-made footwear that does not undergo such improvement, unless it is worn as recommended.

Surgical Treatment of the Infected Diabetic Foot

Foot infections are common in the diabetic patient. Early recognition, proper assessment, and prompt intervention are vital. A combination of surgery and antibiotics is mandatory in virtually all foot infections. The aim of surgery is 2-fold: first, to control the infection, and second, to attempt to salvage the leg. The eventual goal is always to preserve a functional limb. Foot deformities resulting from surgery may cause reulceration and a high morbidity. The surgical treatment of the infection largely consists of draining of pus and removal of all necrotic and infected tissue. Frequently, revascularization of the foot is needed to save the limb; thus, there must be a close cooperation with the vascular surgical service. The surgeon must have a thorough knowledge of foot anatomy and must be familiar with the defects in wound healing that are caused by diabetes. The outcome of surgery mainly depends on the skill, care, and experience of the surgeon. The best results are achieved within a multidisciplinary setting.

Plantar pressure relief in the diabetic foot using forefoot offloading shoes

PURPOSE Forefoot offloading shoes (FOS) are commonly used in clinical practice for treatment of plantar forefoot ulcers in the diabetic foot. The aim of this study was to assess the offloading efficacy of four different FOS models in comparison with a cast shoe and control shoe. METHODS In-shoe plantar pressures were measured during walking in each of the six footwear conditions in 24 neuropathic diabetic patients at high risk for plantar foot ulceration. For each of six foot regions, peak pressure, pressure-time integral, and force-time integral were calculated. Load transfer diagrams were developed to assess the footwear mechanisms of action. Perceived walking comfort was measured using a visual analogue scale (VAS). All comparisons between conditions were tested at P<0.05. RESULTS Peak pressures and pressure-time integrals at the metatarsal heads and hallux regions were significantly reduced (by 38-58%) in all FOS models when compared with the control shoe. The FOS also relieved metatarsal head peak pressure to a significantly larger extent than the cast shoe (approximately 20%). The load transfer diagrams showed a major transfer of approximately 40% of forefoot load to the midfoot explaining the offloading efficacy of the FOS. Perceived walking comfort was significantly lower in the FOS (VAS score 2.7-5.9) when compared with the control shoe (VAS 8.2) and cast shoe (VAS 6.8). CONCLUSIONS The data showed that all FOS models were effective in their primary goal, relieving forefoot pressure in at-risk neuropathic diabetic patients. Therefore, these shoes may be effective in offloading and healing plantar forefoot ulcers, although the low comfort scores should be considered as this may potentially affect adherence to treatment.

Predictors of Lower-Extremity Amputation in Patients With an Infected Diabetic Foot Ulcer

OBJECTIVE Infection commonly complicates diabetic foot ulcers and is associated with a poor outcome. In a cohort of individuals with an infected diabetic foot ulcer, we aimed to determine independent predictors of lower-extremity amputation and the predictive value for amputation of the International Working Group on the Diabetic Foot (IWGDF) classification system and to develop a risk score for predicting amputation. RESEARCH DESIGN AND METHODS We prospectively studied 575 patients with an infected diabetic foot ulcer presenting to 1 of 14 diabetic foot clinics in 10 European countries. RESULTS Among these patients, 159 (28%) underwent an amputation. Independent risk factors for amputation were as follows: periwound edema, foul smell, (non)purulent exudate, deep ulcer, positive probe-to-bone test, pretibial edema, fever, and elevated C-reactive protein. Increasing IWGDF severity of infection also independently predicted amputation. We developed a risk score for any amputation and for amputations excluding the lesser toes (including the variables sex, pain on palpation, periwound edema, ulcer size, ulcer depth, and peripheral arterial disease) that predicted amputation better than the IWGDF system (area under the ROC curves 0.80, 0.78, and 0.67, respectively). CONCLUSIONS For individuals with an infected diabetic foot ulcer, we identified independent predictors of amputation, validated the prognostic value of the IWGDF classification system, and developed a new risk score for amputation that can be readily used in daily clinical practice. Our risk score may have better prognostic accuracy than the IWGDF system, the only currently available system, but our findings need to be validated in other cohorts.

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.

Plantar pressure in off-loading devices used in diabetic ulcer treatment

Four off‐loading devices used for the treatment of diabetic forefoot ulcers were compared: a custom‐molded insole shoe, a cast MABAL shoe, a prefabricated pneumatic walking brace, and a bivalved total contact cast (BTCC). It was anticipated that all devices would significantly reduce forefoot plantar pressure compared with a control shoe. Sixteen healthy volunteers participated. Plantar pressures were evaluated using the Pedar system, while walking speed was determined using an optoelectric timer. Peak pressure (PP) of ten plantar areas and pressure–time integral for the first metatarsal area were analyzed statistically using a repeated measures analysis of variance. Forefoot pressures were significantly reduced compared with the control shoe for all devices (p<0.001). PP was most reduced (by 65.8%) for the BTCC, and pressure–time integral was most reduced for the BTCC and cast MABAL shoe. Small but significant differences between devices in walking speed (p<0.05) could not explain the substantial PP differences between the different devices. Although all off‐loading devices resulted in a significant reduction of forefoot plantar pressure, devices differed significantly in the magnitude of pressure reduction. Further research will have to reveal the level of off‐loading sufficient for effective treatment of diabetic ulcers.

Infrared thermal imaging for automated detection of diabetic foot complications.

Background: Although thermal imaging can be a valuable technology in the prevention and management of diabetic foot disease, it is not yet widely used in clinical practice. Technological advancement in infrared imaging increases its application range. The aim was to explore the first steps in the applicability of high-resolution infrared thermal imaging for noninvasive automated detection of signs of diabetic foot disease. Methods: The plantar foot surfaces of 15 diabetes patients were imaged with an infrared camera (resolution, 1.2 mm/pixel): 5 patients had no visible signs of foot complications, 5 patients had local complications (e.g., abundant callus or neuropathic ulcer), and 5 patients had diffuse complications (e.g., Charcot foot, infected ulcer, or critical ischemia). Foot temperature was calculated as mean temperature across pixels for the whole foot and for specified regions of interest (ROIs). Results: No differences in mean temperature >1.5 °C between the ipsilateral and the contralateral foot were found in patients without complications. In patients with local complications, mean temperatures of the ipsilateral and the contralateral foot were similar, but temperature at the ROI was >2 °C higher compared with the corresponding region in the contralateral foot and to the mean of the whole ipsilateral foot. In patients with diffuse complications, mean temperature differences of >3 °C between ipsilateral and contralateral foot were found. Conclusions: With an algorithm based on parameters that can be captured and analyzed with a high-resolution infrared camera and a computer, it is possible to detect signs of diabetic foot disease and to discriminate between no, local, or diffuse diabetic foot complications. As such, an intelligent telemedicine monitoring system for noninvasive automated detection of signs of diabetic foot disease is one step closer. Future studies are essential to confirm and extend these promising early findings.

Health-Related Quality of Life Predicts Major Amputation and Death, but Not Healing, in People With Diabetes Presenting With Foot Ulcers: The Eurodiale Study

OBJECTIVE Low health-related quality of life (HRQoL) has been consistently reported to be associated with poor prognosis for a variety of health outcomes in various settings. We aimed to evaluate whether HRQoL in patients presenting with new diabetic foot ulcers (DFUs) has prognostic significance for ulcer healing, major amputation, and death. RESEARCH DESIGN AND METHODS We followed 1,088 patients with new DFUs presenting for treatment at one of the 14 centers in 10 European countries participating in the Eurodiale (European Study Group on Diabetes and the Lower Extremity) study, prospectively until healing (76.9%), major amputation (4.6%), or death (6.4%) up to a maximum of 1 year. At baseline, patient and ulcer characteristics were recorded as well as EQ-5D, a standardized instrument consisting of five domains and a visual analog scale for use as a measure of HRQoL. The prognostic influence of the EQ-5D domains was evaluated in multivariable Cox regression analyses on the time-to-event data, adjusting for baseline clinical characteristics of the ulcer and comorbidities. RESULTS While predictive effects of HRQoL, adjusted for possible confounders, were absent for healing, decreased HRQoL, especially in the physical domains, was statistically significant for major amputation (mobility, self-care, usual activities) and death (self-care, usual activities, pain/discomfort). CONCLUSIONS Low HRQoL appears to be predictive for major amputation and death, but high HRQoL does not increase healing. Future studies into the influence of HRQoL on ulcer outcome are important in attempts to decrease treatment failure and mortality.

Diagnostic Values for Skin Temperature Assessment to Detect Diabetes-Related Foot Complications

BACKGROUND Skin temperature assessment is a promising modality for early detection of diabetic foot problems, but its diagnostic value has not been studied. Our aims were to investigate the diagnostic value of different cutoff skin temperature values for detecting diabetes-related foot complications such as ulceration, infection, and Charcot foot and to determine urgency of treatment in case of diagnosed infection or a red-hot swollen foot. MATERIALS AND METHODS The plantar foot surfaces of 54 patients with diabetes visiting the outpatient foot clinic were imaged with an infrared camera. Nine patients had complications requiring immediate treatment, 25 patients had complications requiring non-immediate treatment, and 20 patients had no complications requiring treatment. Average pixel temperature was calculated for six predefined spots and for the whole foot. We calculated the area under the receiver operating characteristic curve for different cutoff skin temperature values using clinical assessment as reference and defined the sensitivity and specificity for the most optimal cutoff temperature value. Mean temperature difference between feet was analyzed using the Kruskal-Wallis tests. RESULTS The most optimal cutoff skin temperature value for detection of diabetes-related foot complications was a 2.2°C difference between contralateral spots (sensitivity, 76%; specificity, 40%). The most optimal cutoff skin temperature value for determining urgency of treatment was a 1.35°C difference between the mean temperature of the left and right foot (sensitivity, 89%; specificity, 78%). CONCLUSIONS Detection of diabetes-related foot complications based on local skin temperature assessment is hindered by low diagnostic values. Mean temperature difference between two feet may be an adequate marker for determining urgency of treatment.

The effect of flexor tenotomy on healing and prevention of neuropathic diabetic foot ulcers on the distal end of the toe

BackgroundFlexor tenotomy is a minimally invasive surgical alternative for the treatment of neuropathic diabetic foot ulcers on the distal end of the toe. The influence of infection on healing and time to heal after flexor tenotomy is unknown. Flexor tenotomy can also be used as a prophylactic treatment. The effectiveness as a prophylactic treatment has not been described before.MethodsA retrospective study was performed with the inclusion of all consecutive flexor tenotomies from one hospital between January 2005 and December 2011.ResultsFrom 38 ulcers, 35 healed (92%), with a mean time to heal of 22 ± 26 days. The longest duration for healing was found for infected ulcers that were penetrating to bone (35 days; p = .042). Cases of prophylactic flexor tenotomies (n=9) did not result in any ulcer or other complications during follow-up.ConclusionsThe results of this study suggest that flexor tenotomy may be beneficial for neuropathic diabetic foot ulcers on the distal end of the toe, with a high healing percentage and a short mean time to heal. Infected ulcers that penetrated to bone took a significantly longer time to heal. Prospective research, to confirm the results of this retrospective study, should be performed.