Incidence of Complications and Risk Factors for Nonunion After Ankle Fracture in Diabetes Mellitus.

BACKGROUND: To evaluate complications and risk factors for nonunion in patients with diabetes after ankle fracture. METHODS: We conducted a retrospective study of 139 patients with diabetes and ankle fractures followed for 1 year. We evaluated the incidence of wounds, infections, nonunions, Charcot's arthropathy, and amputations. We determined Fracture severity (unimalleolar, bimalleolar, trimalleolar), nonunion, and Charcot's arthropathy from radiographs. Nonunion was defined as a fracture that did not heal within 6 months of fracture. Analysis of variance was used to compare continuous variables, and χ2 tests to compare dichotomous variables, with α = 0.05. Logistic regression was performed with a binary variable representing nonunions as the dependent variable. RESULTS: Complications were common: nonunion (24.5%), Charcot's arthropathy (7.9%), wounds (5.2%), wound site infection (17.3%), and leg amputation (2.2%). Patients with nonunions were more likely to be male (55.9% versus 29.5%; P = .005), have sensory neuropathy (76.5% versus 32.4%; P < .001), have end-stage renal disease (17.6% versus 2.9%; P < .001), and use insulin (73.5% versus 40.1%; P < .001), ß-blockers (58.8% versus 39.0%; P = .049), and corticosteroids (26.5% versus 9.5%; P = .02). Among patients with nonunion, there was an increased risk of wounds (odds ratio [OR], 3.3; 95% confidence interval [CI], 1.46-7.73), infection (OR, 2.04; 95% CI, 0.72-5.61), amputation (OR, 7.74; 95% CI, 1.01-100.23), and long-term bracing (OR, 9.51; 95% CI, 3.8-23.8). In the logistic regression analysis, four factors were associated with fracture nonunion: dialysis (OR, 7.7; 95% CI, 1.7-35.2), insulin use (OR, 3.3; 95% CI, 1.5-7.4), corticosteroid use (OR, 4.9; 95% CI, 1.4-18.0), and ankle fracture severity (bimalleolar or trimalleolar fracture) (OR, 2.5; 95% CI, 1.1-5.4). CONCLUSIONS: These results demonstrate risk factors for nonunions: dialysis, insulin use, and fracture severity after ankle fracture in patients with diabetes.

Increased Risk of Nonunion and Charcot Arthropathy After Ankle Fracture in People With Diabetes.

The aim of this study was to evaluate the frequency of complications after an ankle fracture in patients with and without diabetes and to evaluate risk factors for nonunion. We conducted a retrospective study of 439 patients with ankle fractures (31.7% had diabetes) and followed them for 1 year or until the fracture healed. The fracture severity and determination of nonunion and Charcot arthropathy were determined from independent evaluation of radiographs by 2 members of the research team. Nonunion was defined as a fracture that did not heal within 6 months of the fracture. The majority of patients were women (67% in each group). The risk of complications was significantly higher in patients with diabetes compared with those without diabetes. The odds ratio (OR) and 95% confidence interval (CI) for nonunion was 6.5 (3.4 to 12.8); for Charcot arthropathy, 7.6 (2.3 to 21.0); for wounds, 1.8 (1.1 to 2.9); for infection, 2.8 (1.4 to 5.7); and for amputation, 6.6 (0.98 to 80.0). In the logistical regression analysis, 6 factors were associated with fracture nonunion: dialysis (7.7; 1.7 to 35.2), diabetes (3.3; 1.5 to 7.4), fracture severity (bi- and trimalleolar fractures) (4.9; 1.4 to 18.0), beta blockers (2.5; 1.1 to 5.4), steroids (3.1; 1.2 to 7.7), and infection (3.7; 1.2 to 11.3). The results of the study demonstrate the increased risk of complications after an ankle fracture among patients with diabetes, dialysis, or open fractures and those using steroids and beta blockers. Further work is needed to identify areas for risk reduction.

Does the Start of Dialysis Initiate a Period of Increased Risk of Ulceration or Amputation?

BACKGROUND: Dialysis therapy is associated with an increased incidence of lower-extremity wounds and amputations. We compared the incidence of foot ulcers and amputations before and after the start of dialysis. METHODS: We evaluated 150 consecutive diabetic patients receiving dialysis and compared the incidence of foot complications 30 months before and after initiation of hemodialysis. We used claims data for diabetes, ulceration, and dialysis and abstracted medical records to verify diagnoses and dates of ulcers and amputations. We compared initial and cumulative ulcer/amputation incidence to account for multiple events in the same person over time. We used the same formula to determine the incidence rate difference and 95% confidence intervals (CIs) to compare new ulcers and amputations during the study. RESULTS: There was no significant difference in the incidence of first foot ulcers before (91.7 per 1,000 patient-years; 95% CI, 73.7-112.3 per 1,000 patient-years) and after (82.7; 95% CI, 65.7-102.3) the start of hemodialysis. The incidence of cumulative ulcers was significantly higher before (304.0 per 1,000 patient-years; 95% CI, 270.8-340.2) compared with after (210.7 per 1,000 patient-years; 95% CI, 183.0-240.9) dialysis. There was no difference in the incidence of first amputation before (29.3 per 1,000 patient-years; 95% CI, 1 9.4-41.7 per 1,000 patient-years) and after (37.3 per 1,000 patient-years; 95% CI, 19.4-41.7 per 1,000 patient-years) dialysis or in the cumulative incidence of amputations before (61.3 per 1,000 patient-years; 95% CI, 46.7-8.4 per 1,000 patient-years) and after (58.7 per 1,000 patient-years; 95% CI, 44.5-75.5 per 1,000 patient-years) dialysis. CONCLUSIONS: There was no increase in the incidence of ulcers or amputations after beginning hemodialysis.

Amputations and foot-related hospitalisations disproportionately affect dialysis patients.

Patients with diabetes have increased risk for foot ulcers, amputations and hospitalisations. We evaluated a closed cohort of patients with diabetes and established risk factors in two high risk groups: (i) dialysis patients and (ii) patients with previous foot ulceration. We used claims data for diabetes (ICD-9 250.X), ulceration (ICD-9 707·10, 707·14 and 707·15) and dialysis (CPT 90935-90937) from the Scott and White Health Plan to identify 150 consecutive patients with diabetes on dialysis (dialysis group) and 150 patients with a history of foot ulceration (ulcer history group). We verified these diagnoses by manually reviewing corresponding electronic medical records. Each patient was provided 30 months follow-up period. The incidence of foot ulcers was the same in dialysis patients and patients with an ulcer history (210 per 1000 person-years). The amputation incidence rate was higher in dialysis patients (58·0 versus 13·3, P < 0·001). Hospital admission was common in both study groups. The incidence of hospitalisation was higher in the ulcer history group (477·3 versus 381·3, P < 0·001); however, there were more foot-related hospital admissions in the dialysis group (32·9% versus 14·0%, P < 0·001) during the 30-month evaluation period. The incidence of ulcers, amputations and all-cause hospitalisations is high in persons with diabetes and a history of foot ulceration or on dialysis treatment; however, those on dialysis treatment have disproportionately higher rates of foot-related hospitalisations. Intervention strategies to reduce the burden of diabetic foot disease must target dialysis patients as a high-risk group.

Accuracy and durability of Semmes-Weinstein monofilaments: what is the useful service life?

OBJECTIVE: To evaluate the accuracy and effective service life of commercially available Semmes-Weinstein monofilaments with repetitive loading. METHODS: We obtained 6 brands of Semmes-Weinstein monofilaments (SWM) from commercial vendors identified from the Internet and the federal registry. Five monofilaments of each brand were subjected to repeat loading cycles, allowed to rest over night and loaded again the next day. First, sets of five monofilaments were loaded 25 times for each of five days. Then sets of five monofilaments were subjected to 200 loading cycles a day for 15 days. A testing jig ensured each SWM was loaded perpendicular to a digital pressure plate. The buckling force was measured via the pressure plate to determine failure loads. Several statistical techniques were used to examine the behavior of the monofilaments over repeated loadings: time series analysis, ANOVA and nonparametric comparisons of load distributions. RESULTS: The monofilaments tested were neither precise nor accurate. The plasticity of filaments increased with repeated loadings resulting in lower bending forces. Individual and average bending forces varied widely both within and between monofilament brands. All monofilaments showed a typical material failure pattern. Initially the bending force was high but rapidly decreased and then leveled out at levels 1-2g lower than the starting values. After resting over night, the initial bending force was again high but usually not as high as the previous day and bending forces decreased and then leveled out. Most monofilaments did not start at the accepted 10-g buckling force but varied by up to 30% (p<0.01). At best, monofilaments starting at the accepted 10±1g buckling force would remain within a usable range (9-11g) for 7-9 days or to evaluate 70-90 patients. CONCLUSION: Commercially available SWM have significant variability within and between devices from different manufacturers. Their actual bending force varies widely from their designated 10g value. When used they have a short service life where the instrument is within 10% of their initial bending force which is not usually the stated 10g of force.

Impact of chronic kidney disease on survival after amputation in individuals with diabetes.

OBJECTIVE: To identify factors that influence survival after diabetes-related amputations. RESEARCH DESIGN AND METHODS: We abstracted medical records of 1,043 hospitalized subjects with diabetes and a lower-extremity amputation from 1 January to 31 December 1993 in six metropolitan statistical areas in south Texas. We identified mortality in the 10-year period after amputation from death certificate data. Diabetes was verified using World Health Organization criteria. Amputations were identified by ICD-9-CM codes 84.11-84.18 and categorized as foot, below-knee amputation, and above-knee amputation and verified by reviewing medical records. We evaluated three levels of renal function: chronic kidney disease (CKD), hemodialysis, and no renal disease. We defined CKD based on a glomerular filtration rate<60 ml/min and hemodialysis from Current Procedural Terminology (CPT) codes (90921, 90925, 90935, and 90937). We used χ2 for trend and Cox regression analysis to evaluate risk factors for survival after amputation. RESULTS: Patients with CKD and dialysis had more below-knee amputations and above-knee amputations than patients with no renal disease (P<0.01). Survival was significantly higher in patients with no renal impairment (P<0.01). The Cox regression indicated a 290% increase in hazard for death for dialysis treatment (hazard ratio [HR] 3.9, 95% CI 3.07-5.0) and a 46% increase for CKD (HR 1.46, 95% CI 1.21-1.77). Subjects with an above-knee amputation had a 167% increase in hazard (HR 2.67, 95% CI 2.14-3.34), and below-knee amputation patients had a 67% increase in hazard for death. CONCLUSIONS: Survival after amputation is lower in diabetic patients with CKD, dialysis, and high-level amputations.

Does anodyne light therapy improve peripheral neuropathy in diabetes? A double-blind, sham-controlled, randomized trial to evaluate monochromatic infrared photoenergy.

OBJECTIVE: The purpose of this study was to determine the efficacy of anodyne monochromatic infrared photo energy (MIRE) in-home treatments over a 90-day period to improve peripheral sensation and self-reported quality of life in individuals with diabetes. RESEARCH DESIGN AND METHODS: This was a double-blind, randomized, sham-controlled clinical trail. We randomly assigned 69 individuals with diabetes and a vibration perception threshold (VPT) between 20 and 45 V to two treatment groups: active or sham treatment. Sixty patients (120 limbs) completed the study. Anodyne units were used at home every day for 40 min for 90 days. We evaluated nerve conduction velocities, VPT, Semmes-Weinstein monofilaments (SWM) (4-, 10-, 26-, and 60-g monofilaments), the Michigan Neuropathy Screening Instrument (MNSI), a 10-cm visual analog pain scale, and a neuropathy-specific quality of life instrument. We used a nested repeated-measures multiple ANOVA design. Two sites (great toe and fifth metatarsal) were tested on both the left and right feet of each patient, so two feet were nested within each patient and two sites were nested within each foot. To analyze the ordinal SWM scores, we used a nonparametric factorial analysis for longitudinal data. RESULTS: There were no significant differences in measures for quality of life, MNSI, VPT, SWM, or nerve conduction velocities in active or sham treatment groups (P > 0.05). CONCLUSIONS: Anodyne MIRE therapy was no more effective than sham therapy in the treatment of sensory neuropathy in individuals with diabetes.

Reevaluating the way we classify the diabetic foot: restructuring the diabetic foot risk classification system of the International Working Group on the Diabetic Foot.

OBJECTIVE: To separately evaluate peripheral arterial occlusive disease (PAOD) and foot ulcer and amputation history in a diabetic foot risk classification to predict foot complications. RESEARCH DESIGN AND METHODS: We evaluated 1,666 diabetic patients for 27.2 +/- 4.2 months. Patients underwent a detailed foot assessment and were followed at regular intervals. We used a modified version of the International Working Group on the Diabetic Foot's (IWGDF's) risk classification to assess complications during the follow-up period. RESULTS: There were more ulcerations, infections, amputations, and hospitalizations as risk group increased (chi(2) for trend P < 0.001). When risk category 2 (neuropathy and deformity and/or PAOD) was stratified by PAOD, there were more complications in PAOD patients (P < 0.01). When risk group 3 patients (ulceration or amputation history) were separately stratified, there were more complications in subjects with previous amputation (P < 0.01). CONCLUSIONS: We propose a new risk classification that predicts future foot complications better than that currently used by the IWGDF.