The Visualization of Biofilms in Chronic Diabetic Foot Wounds Using Routine Diagnostic Microscopy Methods

Diabetic foot wounds are commonly colonised by taxonomically diverse microbial communities and may additionally be infected with specific pathogens. Since biofilms are demonstrably less susceptible to antimicrobial agents than are planktonic bacteria, and may be present in chronic wounds, there is increasing interest in their aetiological role. In the current investigation, the presence of structured microbial assemblages in chronic diabetic foot wounds is demonstrated using several visualization methods. Debridement samples, collected from the foot wounds of diabetic patients, were histologically sectioned and examined using bright-field, fluorescence, and environmental scanning electron microscopy and assessed by quantitative differential viable counting. All samples (n = 26) harboured bioburdens in excess of 5 log10 CFU/g. Microcolonies were identified in 4/4 samples by all three microscopy methods, although bright-field and fluorescence microscopy were more effective at highlighting putative biofilm morphology than ESEM. Results in this pilot study indicate that bacterial microcolonies and putative biofilm matrix can be visualized in chronic wounds using florescence microscopy and ESEM, but also using the simple Gram stain

Altered joint moment strategy during stair walking in diabetes patients with and without peripheral neuropathy

© 2016 The Authors. Aim: To investigate lower limb biomechanical strategy during stair walking in patients with diabetes and patients with diabetic peripheral neuropathy, a population known to exhibit lower limb muscular weakness. Methods: The peak lower limb joint moments of twenty-two patients with diabetic peripheral neuropathy and thirty-nine patients with diabetes and no neuropathy were compared during ascent and descent of a staircase to thirty-two healthy controls. Fifty-nine of the ninety-four participants also performed assessment of their maximum isokinetic ankle and knee joint moment (muscle strength) to assess the level of peak joint moments during the stair task relative to their maximal joint moment-generating capabilities (operating strengths). Results: Both patient groups ascended and descended stairs slower than controls (p < 0.05). Peak joint moments in patients with diabetic peripheral neuropathy were lower (p < 0.05) at the ankle and knee during stair ascent, and knee only during stair descent compared to controls. Ankle and knee muscle strength values were lower (p < 0.05) in patients with diabetic peripheral neuropathy compared to controls, and lower at knee only in patients without neuropathy. Operating strengths were higher (p < 0.05) at the ankle and knee in patients with neuropathy during stair descent compared to the controls, but not during stair ascent. Conclusion: Patients with diabetic peripheral neuropathy walk slower to alter gait strategy during stair walking and account for lower-limb muscular weakness, but still exhibit heightened operating strengths during stair descent, which may impact upon fatigue and the ability to recover a safe stance following postural instability

Altered leverage around the ankle in people with diabetes: A natural strategy to modify the muscular contribution during walking?

Diabetes patients display gait alterations compared to controls including a higher metabolic cost of walking. This study aimed to investigate whether differences in external moment arm (ExtMA) and effective mechanical advantage (EMA) at the ankle in diabetes patients could partly explain the increased cost of walking compared to controls. Thirty one non-diabetic controls (Ctrl); 22 diabetes patients without peripheral neuropathy (DM) and 14 patients with moderate/severe diabetic peripheral neuropathy (DPN) underwent gait analysis using a motion analysis system and force plates. The internal Achilles tendon moment arm length was determined using magnetic resonance imaging during weight-bearing and ExtMA was calculated using gait analysis. A greater value (P<0.01) for the EMA at the ankle was found in the DPN (0.488) and DM (0.46) groups compared to Ctrl (0.448). The increased EMA was mainly caused by a smaller ExtMA in the DPN (9.63cm; P<0.01) and DM (10.31cm) groups compared to Ctrl (10.42cm) These findings indicate that the ankle plantarflexor muscles would need to generate lower forces to overcome the external resistance during walking compared to controls. Our findings do not explain the previously observedhigher metabolic cost of walking in the DM and DPN groups, but uncover a new mechanism through which patients with diabetes and particularly those with DPN reduce the joint moment at the ankle during walking: by applying the ground reaction force more proximally on the foot, or at an angle directed more towards the ankle, thereby increasing the EMA and reducing the ankle joint moment

A new approach to identifying the effect of diabetic peripheral neuropathy on the ability to drive safely

© 2020 The Authors The purpose of this study was to estimate the potential for impaired driving performance in current drivers with diabetic peripheral neuropathy compared to healthy controls. We analysed, using a driving simulator, three important aspects of driving - use of the accelerator pedal, steering wheel and eye-steering coordination - to test for any differences, and then to integrate these findings to identify a unique pattern of changes in people driving with diabetic peripheral neuropathy. Patients with diabetic peripheral neuropathy displayed differences in use of the accelerator pedal compared to healthy control drivers (p < 0.05) which could be a direct consequence of their sensorimotor impairment due to diabetic peripheral neuropathy. Drivers with DPN used the more extreme high and low positions of the pedal to a greater extent than the Control group who exhibited a more graded use of the accelerator pedal over the mid-range. Eye-steering coordination was also different in drivers with diabetic peripheral neuropathy (p < 0.05) and, as it improved during the second drive, becoming closer to healthy drivers’ values, the occasional loss of control experienced during driving reduced. These insights demonstrate that diabetic peripheral neuropathy affects multiple aspects of driving performance suggesting the need for an integrated approach to evaluate the potential for driving safely in this population

Benefits, Challenges, and Potential Utility of a Gait Database for Diabetes Patients

Gait analysis is a useful tool in understanding movement impairments, which impact on patient well-being. The use of gait analysis in patients with diabetes has led to improvements in health care including the treatment and prevention of ulceration and development of targeted exercise interventions. The current convention when analyzing gait is to address specific complications of diabetes, controlling for potential influencing conditions within a study sample to understand the effects of the few specific complications chosen for analysis. Databases allow for the storage of data in a structured format, allowing easy access to large quantities of data in a consistent, comparable manner. A database of gait analyses of patients with diabetes has the potential to include far greater sample sizes for statistical analyses, allowing multiple influencing factors to be assessed simultaneously, and relationships identified between multiple influencing factors. However, a database of this type would encounter ethical and methodological challenges in its implementation, which are discussed. This article introduces some of the potential benefits, challenges, and utility of a gait database for diabetes patients. We highlight that, whereas the creation of a database within this clinical population would be a complex process both ethically and practically, huge potential benefits could be gained, overcoming some of the limitations faced by traditional isolated gait analysis studies

Do patients with diabetic neuropathy use a higher proportion of their maximum strength when walking?

Diabetic patients have an altered gait strategy during walking and are known to be at high risk of falling, especially when diabetic peripheral neuropathy is present. This study investigated alterations to lower limb joint torques during walking and related these torques to maximum strength in an attempt to elucidate why diabetic patients are more likely to fall. 20 diabetic patients with moderate/severe peripheral neuropathy (DPN), 33 diabetic patients without peripheral neuropathy (DM), and 27 non-diabetic controls (Ctrl) underwent gait analysis using a motion analysis system and force plates to measure kinetic parameters. Lower limb peak joint torques and joint work done (energy expenditure) were calculated during walking. The ratio of peak joint torques and individual maximum joint strengths (measured on a dynamometer) was then calculated for 59 of the 80 participants to yield the ‘operating strength’ for those participants. During walking DM and DPN patients showed significantly reduced peak torques at the ankle and knee. Maximum joint strengths at the knee were significantly less in both DM and DPN groups than Ctrls, and for the DPN group at the ankle. Operating strengths were significantly higher at the ankle in the DPN group compared to the Ctrls. These findings show that diabetic patients walk with reduced lower limb joint torques; however due to a decrement in their maximum ability at the ankle and knee, their operating strengths are higher. This allows less reserve strength if responding to a perturbation in balance, potentially increasing their risk of falling