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OBJECTIVE This study investigated the effects of vibrating insoles on dynamic balance and gait quality during level and stair walking and explored the influence of vibration type and frequency in individuals with diabetic peripheral neuropathy (DPN). RESEARCH DESIGN AND METHODS Twenty-two men with DPN were assessed for gait quality and postural and dynamic balance during walking and stair negotiation using a motion capture system and force plates across seven vibratory insole conditions (Vcs) versus a control (Ctrl) condition (insole without vibration). Vibration was applied during standing and walking tasks, and 15-min rest-stop periods without vibration were interposed between conditions. Repeated measures test conditions were randomized. The primary outcomes were gait speed and dynamic balance. RESULTS Gait speed during walking significantly improved in all Vcs compared with Ctrl (P < 0.005), with Vc2, Vc4, and Vc6 identified as the most effective. Gait speed increased (reflecting faster walking) during stair ascent and descent in Vc2 (Ctrl vs. Vc2 for ascent 0.447 ± 0.180 vs. 0.517 ± 0.127 m/s; P = 0.037 and descent 0.394 ± 0.170 vs. 0.487 ± 0.125 m/s; P = 0.016), Vc4 (Ctrl vs. Vc4 for ascent 0.447 ± 0.180 vs. 0.482 ± 0.197 m/s; P = 0.047 and descent 0.394 ± 0.170 vs. 0.438 ± 0.181 m/s; P = 0.017), and Vc6 (Ctrl vs. Vc6 for ascent 0.447 ± 0.180 vs. 0.506 ± 0.179 m/s; P = 0.043 and descent 0.394 ± 0.170 vs. 0.463 ± 0.159 m/s; P = 0.026). Postural balance improved during quiet standing with eyes closed in Vc2, Vc4, Vc6, and Vc7 (P < 0.005). CONCLUSIONS Vibrating insoles are an effective acute strategy for improving postural balance and gait quality during level walking and stair descent in individuals with DPN. These benefits are particularly evident when the entire plantar foot surface is stimulated.

Background and Objectives: Barefoot peak plantar pressures (PPPs) are elevated in diabetes patients with neuropathic foot ulcer (DFU) history; however, there is limited reported evidence for a causative link between high barefoot PPP and DFU risk. We aimed to determine, using a simple mat-based methodology, the site-specific, barefoot PPP critical threshold that will identify a plantar site with a previous DFU. Materials and Methods: In a cross-sectional study, barefoot, site-specific PPPs were measured with normal gait for patients with DFU history (n = 21) and healthy controls (n = 12), using a validated carbon footprint system. For each participant, PPP was recorded at twelve distinct plantar sites (1st–5th toes, 1st–5th metatarsal heads (MTHs), midfoot and heel), per right and left foot, resulting in the analysis of n = 504 distinct plantar sites in the diabetes group, and n = 288 sites in the control group. Receiver operator characteristic curve analysis determined the optimal critical threshold for sites with DFU history. Results: Median PPPs for the groups were: diabetes sites with DFU history (n = 32) = 5.0 (3.25–7.5) kg/cm2, diabetes sites without DFU history (n = 472) = 3.25 (2.0–5.0) kg/cm2, control sites (n = 288) = 2.0 (2.0–3.25) kg/cm2; (p < 0.0001). Diabetes sites with elevated PPP (>6 kg/cm2) were six times more likely to have had DFU than diabetes sites with PPP ≤ 6 kg/cm2 (OR = 6.4 (2.8–14.6, 95% CI), p < 0.0001). PPP > 4.1 kg/cm2 was determined as the optimal critical threshold for identifying DFU at a specific plantar site, with sensitivity/specificity = 100%/79% at midfoot; 80%/65% at 5th metatarsal head; 73%/62% at combined midfoot/metatarsal head areas. Conclusions: We have demonstrated, for the first time, a strong, site-specific relationship between elevated barefoot PPP and previous DFU. We have determined a critical, highly-sensitive, barefoot PPP threshold value of >4.1 kg/cm2, which may be easily used to identify sites of previous DFU oc

Aims To prospectively explore the association between sedentary time (SED-time) and the development of diabetic foot ulcer (DFU) in people with diabetic peripheral neuropathy (DPN). Methods 175 DPN individuals who attended the annual evaluation for the SAMBA Study (2012–2019) were included. Main outcome measure was the first diagnosis of DFU. SED-time was measured by the PAS 2.1 questionnaire. Nerve function was evaluated by nerve conduction studies. Vascular function was assessed by Ankle-brachial index (ABI) and pedal pulses. Foot deformity and skin dryness were examined by visual inspection. Results 62 participants (35.5%) developed a DFU during the study. SED-time was significantly higher in people who developed DFUs (12.8 ± 3.0 vs 9.4 ± 3.1 h/day). Logistic regression showed that among several nervous (motor amplitude, OR 0.33, 95% CI, 0.18–0.60; sensory amplitude, 0.85, 0.77–0.94) and vascular parameters (ABI, 0.23, 0.1–0.61; pedal pulses, 2.81, 0.12–0.63) and foot characteristics (deformity, 2.63, 1.30–5.32; skin dryness, 2.04, 0.95–4.37), SED-time was one of the strongest variables contributing to the development of DFUs (2.95, 1.45–6.44). Conclusions SED-time is an independent predictor of the risk of DFU in people with DPN. The monitoring of SED-time with strategies aimed at reducing it should be included in the standard care of diabetic patients.

Aims High plantar pressure is a major risk factor in the development of diabetic foot ulcers (DFUs) and recent evidence shows plantar pressure feedback reduces DFU recurrence. This study investigated whether continued use of an intelligent insole system by patients at high-risk of DFUs causes a reduction in plantar pressures. Methods Forty-six patients with diabetic peripheral neuropathy and previous DFU were randomised to intervention (IG) or control groups (CG). Patients received an intelligent insole system, consisting of pressure-sensing insoles and digital watch. Patients wore the device during all daily activity for 18-months or until ulceration, and integrated pressure was recorded continuously. The device provided high-pressure feedback to IG only via audio-visual-vibrational alerts. High-pressure parameters at the whole foot, forefoot and rearfoot were compared between groups, with multilevel binary logistic regression analysis. Results CG experienced more high-pressure bouts over time than IG across all areas of the foot (P < 0.05). Differences between groups became apparent >16 weeks of wearing the device. Conclusions Continuous plantar pressure feedback via an intelligent insole system reduces number of bouts of high-pressure in patients at high-risk of DFU. These findings suggest that patients were learning which activities generated high-pressure, and pre-emptively offloading to avoid further alerts.

OBJECTIVE To assess the diagnostic utility of corneal confocal microscopy (CCM) for diabetic peripheral neuropathy (DPN) and the risk factors for corneal nerve loss. RESEARCH DESIGN AND METHODS A total of 490 participants, including 72 healthy control subjects, 149 with type 1 diabetes, and 269 with type 2 diabetes, underwent detailed assessment of peripheral neuropathy and CCM in relation to risk factors. RESULTS Corneal nerve fiber density (CNFD) (P <0.0001 and P <0.0001), corneal nerve fiber branch density (CNBD) (P <0.0001 and P <0.0001), and corneal nerve fiber length (CNFL) (P <0.0001 and P = 0.02) were significantly lower in patients with type 1 and type 2 diabetes compared with control subjects. CNFD (P <0.0001), CNBD (P <0.0001), and CNFL (P <0.0001) were lower in type 1 diabetes compared with type 2 diabetes. Receiver operating characteristic curve analysis for the diagnosis of DPN demonstrated a good area under the curve for CNFD of 0.81, CNBD of 0.74, and CNFL of 0.73. Multivariable regression analysis showed a significant association among reduced CNFL with age (beta = -0.27, P = 0.007), HbA(1c) (beta = -1.1; P = 0.01), and weight (beta = -0.14; P = 0.03) in patients with type 2 diabetes and with duration of diabetes (beta = -0.13; P = 0.02), LDL cholesterol (beta = 1.8, P = 0.04), and triglycerides (beta = -2.87; P = 0.009) in patients with type 1 diabetes. CONCLUSIONS CCM identifies more severe corneal nerve loss in patients with type 1 diabetes compared with type 2 diabetes and shows good diagnostic accuracy for DPN. Furthermore, the risk factors for a reduction in corneal nerve fiber length differ between type 1 and type 2 diabetes.