Electric Stimulation as an Effective Adjunctive Therapy for Diabetic Foot Ulcer: A Meta-analysis of Randomized Controlled Trials

Molecular immunological mechanisms of impaired wound healing in diabetic foot ulcers (DFU), current therapeutic strategies and future directions

Diabetic foot ulcer (DFU) is a foremost cause of amputation in diabetic patients. Consequences of DFU include infections, decline in limb function, hospitalization, amputation, and in severe cases, death. Immune cells including macrophages, regulatory T cells, fibroblasts and other damage repair cells work in sync for effective healing and in establishment of a healthy skin barrier post-injury. Immune dysregulation during the healing of wounds can result in wound chronicity. Hyperglycemic conditions in diabetic patients influence the pathophysiology of wounds by disrupting the immune system as well as promoting neuropathy and ischemic conditions, making them difficult to heal. Chronic wound microenvironment is characterized by increased expression of matrix metalloproteinases, reactive oxygen species as well as pro-inflammatory cytokines, resulting in persistent inflammation and delayed healing. Novel treatment modalities including growth factor therapies, nano formulations, microRNA based treatments and skin grafting approaches have significantly augmented treatment efficiency, demonstrating creditable efficacy in clinical practices. Advancements in local treatments as well as invasive methodologies, for instance formulated wound dressings, stem cell applications and immunomodulatory therapies have been successful in targeting the complex pathophysiology of chronic wounds. This review focuses on elucidating the intricacies of emerging physical and non-physical therapeutic interventions, delving into the realm of advanced wound care and comprehensively summarizing efficacy of evidence-based therapies for DFU currently available.

The effect of high-voltage monophasic pulsed current on diabetic ulcers and their potential pathophysiologic factors: A systematic review and meta-analysis

The present review was conducted to determine the efficacy of high-voltage monophasic pulsed current (HVMPC) in treating diabetic ulcers, assess its effect on skin lesions with each of the pathophysiologic factors potentially contributing to diabetic ulcers, evaluate its safety, and identify treatment parameters. Electronic search of PubMed, Scopus, PEDro and Google Scholar databases was conducted. The revised tool for assessing risk of bias in randomised trials (RoB 2), the risk of bias in non-randomised studies-of interventions (ROBINS-I) and the Joanna Briggs Institute (JBI) critical appraisal tool were used to assess risk of bias and methodological quality. Overall quality of evidence was determined using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) principles. Thirty-two studies matched the eligibility criteria, and included 1061 patients with 1103 skin lesions of selected aetiologies; 12 randomised controlled trials were included in quantitative synthesis. HVMPC plus standard wound care (SWC) likely increased the probability of complete wound healing of pressure ulcers (PrUs) compared with sham/no stimulation plus SWC; relative risk (RR) 2.08; 95% CI: [1.42, 3.04], p = 0.0002; I²  = 0%, p = 0.61; eight studies, 358 ulcers. Although conclusive evidence regarding the effect of HVMPC on diabetic ulcers was not found, collateral evidence might suggest a potential benefit. Direct evidence, with moderate certainty, may support its efficacy in treating PrUs, albeit few adverse reactions were reported. Other observations, moreover, might indicate that this efficacy may not be limited to PrUs. Nonetheless, several aspects remain to be clarified for safe and effective application of electrical stimulation for wound healing.

Home-Based Electrical Stimulation to Accelerate Wound Healing-A Double-Blinded Randomized Control Trial

BACKGROUND

Electrical stimulation (E-Stim) may offer a unique adjunctive treatment to heal complicated diabetic foot ulcers (DFU). Our primary goal is to examine the effectiveness of daily home-based E-Stim therapy to speed-up wound healing.

METHODS

Patients with chronic DFUs and mild to severe peripheral arterial disease (PAD) were recruited and randomized to either control (CG) or intervention (IG) groups. The IG received 1-hour home-based E-Stim therapy on daily basis for 4 weeks (4W). E-Stim was delivered through electrical pads placed above the ankle joint using a bio-electric stimulation technology (BEST^®) platform (Tennant Biomodulator^® PRO). The CG was provided with an identical but non-functional device for the same period. The primary outcome included wound area reduction at 4W from baseline (BL).

RESULTS

Thirty-eight patients were recruited and 5 were removed due to non-compliance or infection, leaving 33 participants (IG, n = 16; CG, n =17). At 4W, the IG showed a significant wound area reduction of 22% (BL: 7.4 ± 8.5 cm² vs 4W: 5.8 ± 8.0 cm², P = 0.002). Average of wound area was unchanged in the CG (P = 0.982). The self-report adherence to daily home-therapy was 93.9%.

CONCLUSIONS

Daily home-based E-Stim provides early results on the feasibility, acceptability, and effectiveness of E-Stim as an adjunctive therapy to speed up wound healings in patients with chronic DFU and mild to severe PAD.

Effect of electrical stimulation on patients with diabetes-related ulcers: a systematic review and meta-analysis

BACKGROUND

This study aimed to systematically review the literature to better understand the efficacy of electrical stimulation (ES) for the treatment of patients with diabetes-related ulcers.

METHODS

We searched the Embase, Medline, and Cochrane Library databases through July 31, 2021. Original trials for ES treatment of patients with diabetes-related ulcers with placebo or standard care as the control group were included. The primary outcomes were ulcer area reduction and healing rates. Meta-analyses were performed to compare the standardized mean difference (SMD) in the percentage of ulcer reduction and risk ratio of non-healing rates between ES treatment and placebo or standard care. We used the Revised Cochrane risk-of-bias tool for randomized trials to assess the risk of bias for each included article. Funnel plots and Egger's test were used to assess publication bias.

RESULTS

Compared to placebo or standard care, ES had a significant benefit for the treatment of patients with diabetes-related ulcers in terms of percentage of ulcer reduction (SMD = 2.56, 95% CI: 1.43-3.69; P < 0.001 (Q-test), I² = 93.9%) and ulcer healing rates [risk ratio of non-healing rates for the ES group was 0.72 (95% CI: 0.54-0.96; P = 0.38 (Q-test), I² = 2.3%)]. Two, four, and three of the included studies were categorized into low risk of bias, some concerns, and high risk of bias, respectively. No publication bias was found.

CONCLUSIONS

Based on the findings of this meta-analysis, ES could be used to treat patients with diabetes-related ulcers. ES treatment was effective for ulcer area reduction and ulcer healing, although it had a high heterogeneity level among the included studies. Pulsed current ES has the potential benefit of increasing ulcer healing compared to direct current ES. Further large-scale clinical trials are needed to define the adverse events and potentiators of ES in the treatment of patients with diabetes-related ulcers.