This investigation evaluates the effects of diabetes on the mechanical properties of human bone, specifically, the tibia. Seven diabetic and seven nondiabetic human (male) cadaveric distal tibiae were used in this study. The average age of the diabetic cadaveric samples was 51 years (range, 46–61 years), and the average age of the nondiabetic cadaveric samples was 75 years (range, 67–85 years). Three-point bending tests for strength and stiffness were performed on a small sample of each distal tibia. Each specimen was loaded at a constant rate until failure. From the recorded curve of load versus displacement, the ultimate and yield strength of bone and the bending modulus of bone were calculated. The diabetic samples were generally weaker than the older, nondiabetic samples, but no statistically significant differences were found in the elastic modulus (P = .29), yield strength (P = .90), ultimate strength (P = .46), and fracture toughness (P = .78), leading to speculation that diabetes has an effect similar to that of aging on the musculoskeletal system. (J Am Podiatr Med Assoc 96(2): 91–95, 2006)
One hundred eighty-seven type 2 diabetic patients without a history of foot ulceration were followed for a mean period of 3.6 years to investigate the incidence of foot ulceration in a diabetes cohort and to analyze risk factors for foot ulceration by multivariate means. During the study, 10 subjects developed 18 forefoot ulcerations. In multivariate logistic regression, significant predictors for foot ulceration were an elevated vibration perception threshold (VPT) (relative risk [RR] = 25.4), an increased plantar pressure (RR = 6.3), and daily alcohol intake (RR = 5.1). This is the first prospective study to demonstrate plantar pressure and daily alcohol intake as predictors of foot ulceration among patients without previous ulceration. Further, VPT could be confirmed as the strongest predictor for foot ulceration, and it was clearly demonstrated that the more pronounced severity of complications occurred among subjects with elevated VPT. (J Am Podiatr Med Assoc 91(7): 343-350, 2001)
Diabetes mellitus is a predisposing factor for onychomycosis (OM). A high frequency of nonfungal onychodystrophy (OD) is also alleged, although information on the prevalence of specific nail changes is scant. We evaluated the prevalence and types of nail changes in a cohort of diabetic patients with fungal and nonfungal OD.
During a 6-month period, inpatients with diabetes mellitus were screened for foot and toenail changes. Demographic, social, and clinical data were recorded, as was information concerning foot and toenail care. Fungal infection was confirmed by mycologic examination and by histologic analysis of nail clippings.
Of the 82 patients included, 65 (79.3%) had nail changes, and 34 of these 65 patients (52.3%) were diagnosed as having OM. The most frequently observed nail signs were subungual hyperkeratosis, onycholysis, yellow discoloration, and splinter hemorrhages, each seen in more than 25% of the patients. Tinea pedis and superficial pseudoleukonychia were observed more frequently in the OM group (P < .05). Conversely, prominent metatarsal heads and history of nail trauma were more frequent in patients with nonfungal OD (P < .05).
Physicians who care for diabetic patients should not ignore nail changes. Fungal and nonfungal OD are common and should be addressed in the global evaluation of the feet to help prevent breaks in the skin barrier and subsequent bacterial infections and ulcers.
Background: An open-label, noncomparative study was conducted to assess the safety and efficacy of ciclopirox 8% nail lacquer topical solution in patients with type 2 diabetes mellitus.
Methods: Forty-nine diabetic patients with distal subungual onychomycosis were treated once daily for 48 weeks with ciclopirox 8% nail lacquer, a topical nail solution approved for the treatment of patients with mild-to-moderate onychomycosis.
Results: Treatment resulted in clinical improvement in 63.4% of patients. Most patients (85.7%) had a mycologic outcome of improvement or cure, with 54.3% attaining mycologic cure. Consideration of mycologic and clinical outcomes generated a treatment outcome of improvement, success, or cure in 84.4% of patients. Moreover, patients experienced improvement in the diseased area of the nail (63.4%), nail surface (56.1%), nail color (48.8%), and nail thickness (65.9%). Ciclopirox 8% nail lacquer was safe, with treatment-related adverse events limited to infection in one patient, which resolved in 15 days; the patient completed the study. No treatment-related serious adverse events were observed.
Conclusion: Ciclopirox 8% nail lacquer is a safe and effective treatment for distal subungual onychomycosis in patients with type 2 diabetes mellitus receiving insulin or oral hypoglycemic therapy. (J Am Podiatr Med Assoc 97(3): 195–202, 2007)
In this study of people with diabetes mellitus and peripheral neuropathy, it was found that the feet of patients with a history of hallux ulceration were more pronated and less able to complete a single-leg heel rise compared with the feet of patients with a history of ulceration elsewhere on the foot. The range of active first metatarsophalangeal joint dorsiflexion was found to be significantly lower in the affected foot. Ankle dorsiflexion, subtalar joint range of motion, and angle of gait differed from normal values but were similar to those found in other studies involving diabetic subjects and were not important factors in the occurrence of hallux ulceration. These data indicate that a more pronated foot type is associated with hallux ulceration in diabetic feet. Further studies are required to evaluate the efficacy of footwear and orthoses in altering foot posture to manage hallux ulceration. (J Am Podiatr Med Assoc 96(3): 189–197, 2006)
Toe pressures and the toe brachial index (TBI) represent possible screening tools for peripheral arterial disease; however, limited evidence is available regarding their reliability. The aim of this study was to determine intratester and intertester reliability of toe systolic pressure and the TBI in participants with and without diabetes performed by podiatric physicians.
Two podiatric physicians performed toe and brachial pressure measurements on 80 participants, 40 with and 40 without diabetes, during two testing sessions using photoplethysmography and Doppler probe. Intraclass correlation coefficients (ICCs) and 95% limits of agreement were determined.
In people with diabetes, intratester reliability of toe pressure measurement was excellent for both testers (ICCs, 0.84 and 0.82). Reliability of the TBI was good (ICCs, 0.72 and 0.75) and brachial pressure fair (ICCs, 0.43 and 0.55). The intertester reliability of toe pressure (ICC, 0.82) and the TBI (ICC, 0.80) was excellent. Intertester reliability of brachial pressure was reduced in people with diabetes (ICC, 0.49). In age-matched participants, intratester reliability of toe pressure measurement was excellent for both testers (ICCs, 0.83 and 0.87), and reliability of the TBI (ICCs, 0.74 and 0.80) and brachial pressure (ICCs, 0.73 and 0.78) was good to excellent. Intertester reliability of toe pressure (ICC, 0.84), the TBI (ICC, 0.81), and brachial pressure (ICC, 0.77) was excellent.
Toe pressures and the TBI demonstrated excellent reliability in people with and without diabetes and can be an effective component of lower-extremity vascular screening. However, wide limits of agreement relative to blood pressure values for both cohorts indicate that results should be interpreted with caution.
Metabolic disorders are known to alter the mechanical properties of tendons. We sought to evaluate the prevalence of asymptomatic Achilles tendon enthesopathic changes in patients with type 2 diabetes mellitus (T2DM) without peripheral neuropathy.
We recruited 43 patients with T2DM and 40 controls. Neuropathy was excluded with the Michigan Neuropathy Scoring Instrument. Bilateral ultrasonography of the Achilles tendon enthesis was performed.
Patients with T2DM had a higher prevalence of hypoechogenicity (26.7% versus 2.5%; P = .0001), entheseal thickening (24.4% versus 8.7%; P = .007), and enthesophytes (74.4% versus 57.5%; P = .02). No differences were found in the number of patients with erosions (1.2% versus 0%; P > .99), cortical irregularities (11.6% versus 3.7%; P = .09), bursitis (5.8% versus 3.7%; P = .72), or tears (2.3% versus 1.2%; P > .99). The mean ± SD sum of abnormalities was higher in patients with T2DM (1.5 ± 1.1 versus 0.7 ± 0.6; P < .0001), as was the percentage of bilateral involvement (72.1% versus 45.0%; P = .01). Mean ± SD thickness did not differ between patients and controls (4.4 ± 1.1 mm versus 4.2 ± 0.8 mm; P = .07).
According to our data, there is an elevated prevalence of asymptomatic Achilles tendon enthesopathic changes in patients with T2DM independent of peripheral neuropathy.
Diabetes-related lower limb amputations (LLAs) are a major complication that can be reduced by employing multidisciplinary center frameworks such as the Toe and Flow model (TFM). In this study, we investigate the LLAs reduction efficacy of the TFM compared to the standard of care (SOC) in the Canadian health-care system.
We retrospectively reviewed the anonymized diabetes-related LLA reports (2007-2017) in Calgary and Edmonton metropolitan health zones in Alberta, Canada. Both zones have the same provincial health-care coverage and similar demographics; however, Calgary operates based on the TFM while Edmonton with the provincial SOC. LLAs were divided into minor and major amputation cohorts and evaluated using the chi-square test, linear regression. A lower major LLAs rate was denoted as a sign for higher efficacy of the system.
Although LLAs numbers remained relatively comparable (Calgary: 2238 and Edmonton: 2410), the Calgary zone had both significantly lower major (45%) and higher minor (42%) amputation incidence rates compared to the Edmonton zone. The increasing trend in minor LLAs and decreasing major LLAs in the Calgary zone were negatively and significantly correlated (r = -0.730, p = 0.011), with no significant correlation in the Edmonton zone.
Calgary's decreasing diabetes-related major LLAs and negative correlation in the minor-major LLAs rates compared to its sister zone Edmonton, provides support for the positive impact of the TFM. This investigation includes support for a modernization of the diabetes-related limb preservation practice in Canada by implementing TFMs across the country to combat major LLAs.
The relationship between hyperglycemia and adverse outcomes after surgery has been widely documented. Long-term glucose control has been recognized as a risk factor for postoperative complications. In the foot and ankle literature, long-term glycemic control as a potential perioperative risk factor is not well studied. Our goal was to investigate whether hemoglobin A1c (HbA1c) level was independently associated with postoperative complications in a retrospective cohort study.
Three hundred twenty-two patients with a diagnosis of diabetes mellitus were enrolled in the study to assess risk factors associated with postoperative foot and ankle surgery complications.
Bivariate analyses showed that HbA1c level and having at least one comorbidity were associated with postoperative infections. However, after adjusting for other covariates, the only significant factor was HbA1c level, with each increment of 1% increasing the odds of infection by a factor of 1.59 (95% confidence interval [CI], 1.28–1.99). For postoperative wound-healing complications, bivariate analyses showed that body mass index, having at least one comorbidity, and HbA1c level were significant factors. After adjusting for other covariates, the only significant factors for developing postoperative wound complications were having at least one comorbidity (odds ratio, 2.03; 95% CI, 1.22–3.37) and HbA1c level (each 1% increment) (odds ratio, 1.25; 95% CI, 1.02–1.53).
In this retrospective study, HbA1c level had the strongest association with postoperative foot and ankle surgery complications in patients with diabetes.
First-line therapy for diabetic patients presenting with intermittent claudication includes supervised exercise programs to improve walking distance. However, exercise comes with a variety of barriers and may be contraindicated in certain conditions. The aim of this study was to evaluate whether calf muscle electrostimulation improves claudication distance.
A prospective, one-group, pretest-posttest study design was used on 40 participants living with type 2 diabetes mellitus, peripheral artery disease (ankle brachial pressure index, <0.90), and calf muscle claudication. Calf muscle electrostimulation of varying frequencies (1–250 Hz) was prescribed on both limbs for 1-hour daily sessions for 12 consecutive weeks. The absolute claudication distance (ACD) was measured at baseline and after the intervention.
The recruited cohort (30 men and ten women; mean age, 71 years; mean ankle brachial pressure index, 0.70) registered a mean ± SD baseline ACD of 333.71 ± 208 m. After a mean ± SD of 91.68 ± 6.23 days of electrical stimulation, a significant mean ± SD increase of 137 ± 136 m in the ACD (P = .001, Wilcoxon signed rank test) was registered. Improvement was found to be sex independent, but age was negatively correlated with proportion of improvement (r = –0.361; P = .011, Pearson correlation test).
Electrical stimulation of varying frequencies on ischemic calf muscles significantly increased the maximal walking capacity in claudicants with type 2 diabetes. This therapeutic approach should be considered in patients with impaired exercise tolerance or as an adjunct treatment modality.