Electrical Stimulation for the Treatment of Pain and Muscle Rehabilitation

MEDLINE, EMBASE, Twenty studies met inclusion criteria. Outcomes were ADL (primary), functional motor ability (secondary) and other motor outcomes (tertiary). Quality assessment was determined using GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria. In 6 studies, no significant benefit of FES was found for objective ADL measures (FES group participants = 67). A significant benefit on ADLs was demonstrated in an analysis of three studies where FES was initiated on average within 2 months post-stroke (n=32). No significant ADL improvements were seen in 3 studies where FES was initiated more than 1 year after stroke (n=35). Quality assessment using GRADE found very low-quality evidence in all analyses due to heterogeneity, low participant numbers and lack of blinding. Meta-analyses gave rise to certain limitations. including but not limited to the utilization of many different measurement instruments and only a minority were employed by more than a few studies, as well as inadequate participant blinding in most studies. The authors concluded that FES is a promising therapy which could play a part in future stroke rehabilitation. There is a need for high quality large-scale randomized controlled trials of upper limb FES after stroke to draw firm conclusions regarding its efficacy or its optimum therapeutic window (2017). part by Walk Test, Timed Go Test, Status (EDSS) and Composite score. QOL using the 36 (SF-36). Improvements seen in the Test, Timed and and Go tests. but in but The physical and health sub-scores and the total and seen in comparison of TMARP alone on quadriceps muscle strength, functional mobility, and pain in military service members after a combat-related lower extremity amputation. In total, 44 participants with a unilateral transtibial amputation were randomly assigned to the TMARP plus NMES (n=23) or to TMARP alone (n=21). Both groups received 12 weeks of the traditional amputee rehabilitation, including pre- and post-prosthetic training. Those in the NMES group also received 12 weeks of NMES. Participants were tested at 3-week intervals during the study for muscle strength and pain. For functional measures, they were tested after receiving their prosthesis and at study completion (weeks 6 and 12). In both groups, residual limb quadriceps muscle strength and pain severity improved from baseline to 12 weeks. The NMES plus TMARP group showed greater strength than the TMARP alone group at 3 weeks, before receiving the prosthesis. However, 6 weeks post-prosthesis, there was no group difference in the residual limb strength. weeks and leg research NMES recovery. and physical function in patients with knee osteoarthritis. The review included eight RCTs that that compared PEMF of various parameters and treatment regimens with placebo. The studies involved 421 patients of similar age, sex ratio, and body mass index. All the included studies were determined by the reviewers to have a low or moderate risk of bias. The limitations noted by the authors included the small number of RCTs and sample size available for review, the inclusion of only articles published in English and that there was significant heterogeneity in the meta-analysis of the visual analogue scale (VAS) for pain. The authors concluded that PEMF is beneficial for improving physical function of the knee joint despite not having any advantage in treating pain or stiffness. They recommend further RCTs to confirm their findings and to determine the optimal frequency, intensity, treatment regimen and duration of PEMF therapy. for PNS for pain: ReActiv8 Implantable Neurostimulation System for Treating Chronic Pain (2021), Sprint Peripheral Nerve Stimulation System for Treating Peripheral Nerve Pain (2020), StimRouter Neuromodulation System for Treating Peripheral Nerve Pain (2020), and StimQ Peripheral Nerve Stimulator System for Treating Peripheral Nerve Pain (2018). All of these reports indicate that the evidence is inconclusive since there are too few data. Gilligan et al (2021) conducted a randomized double-blinded, sham-controlled clinical trial at 26 specialist pain centers to determine the safety and efficacy of an implantable, restorative neurostimulator, the ReActiv8 Implantable Neurostimulation System. This study included 240 participants with refractory mechanical chronic low back pain (LBP) with an impaired multifidus control who continued with LBP despite >90 days of medical management and at least one attempt of physical therapy. The participants were implanted and randomized using a permuted block scheme for each investigational site to the therapeutic group (N=102) or the sham control group (N=102). All participants received stimulation, either therapeutic or low-level sham, twice a day for 120 days. After the primary endpoint, all reported outcomes were unblinded and all participants received therapeutic stimulation. All study participants were evaluated through 1 year for long-term outcomes and adverse events. The authors reported that 64% of participants had a 50% or greater improvement in their LBP, mean disability improved by 51% from borderline “severe” to “minimal” and that 18 of the 65 participants who were on opioids at baseline discontinued their use. They also reported a 4% serious adverse events rate, including 6 pocket infections requiring system removal. The authors concluded that this study provided important insights and design considerations for future neuromodulation trials. In a prospective, multicenter single-arm case series on the effect of PNS on treating chronic axial back pain, Gilmore et al (2021), determined that percutaneous PNS may provide a promising first-line neurostimulation treatment option. The study included 81 participants and was conducted across a variety of clinical care settings. All participants were implanted with percutaneous open-coil PNS leads which were then connected to the SPRINT PNS System. The of percutaneous PNS for neuropathic following amputation. Twenty-eight lower extremity amputees with postamputation pain were enrolled in the study. Subjects underwent ultrasound-guided implantation of PNS leads and were randomized to receive PNS or placebo for 4 weeks. The placebo group then crossed over and all subjects received PNS for four additional weeks. The primary efficacy endpoint evaluated the proportion of subjects reporting ≥50% pain reduction during weeks 1-4. A significantly greater proportion of subjects receiving PNS (n=7/12, 58%, p=0.037) demonstrated ≥50% reductions in average postamputation pain during weeks 1-4 compared with subjects receiving placebo (n=2/14, 14%). Two subjects were excluded from efficacy analysis due to eligibility changes. Significantly greater proportions of PNS subjects also reported ≥50% reductions in pain (n=8/12, 67%, p=0.014) and pain interference (n=8/10, 80%, p=0.003) after 8 weeks of therapy compared with subjects receiving placebo (pain: n=2/14, 14%; pain interference: n=2/13, 15%). The investigators concluded that this study demonstrates that percutaneous PNS therapy may provide enduring clinically significant pain relief and improve disability in patients with chronic neuropathic postamputation pain. Study limitations included small sample size, short follow-up period (4 weeks.), no significant difference in opioid usage reductions between groups, even though the PNS therapy group had greater absolute and percent reductions in average opioid usage. study participants. The participants were randomized into the treatment group (n=26) or the placebo-control group (n=26). Participants wore the electrodes with the active or placebo microcurrent treatment for three consecutive hours per day and abstained from pain or anti-inflammatory medications throughout the four-week study. Daily text reminders were sent to use the device. This method demonstrated high compliance as it required participants to respond with an affirmative response or repetitive reminder texts would be sent until confirmation of compliance was achieved. The authors reported the study showed a trend in increased function that correlated well with a decrease in pain, especially in the 3 rd week, and decreased effusion on musculoskeletal ultrasound imaging over the first two weeks in the active MENS group versus the placebo group. Limitations noted by the authors include the small number of participants, the use of the Lower Extremity Function Scale (LEFS) as it appeared to not be sensitive enough in this population to capture changes in function, and the lack of long-term follow-up. They concluded that MENS decreased knee pain and increased function and that it may be an alternative or be used with a pharmacological approach for people with acute knee pain. The authors recommend future studies evaluate the effect MENS has on edema via musculoskeletal ultrasound elastography, the effect different dosages of MENS have in the perception of specific acute knee pain and function, longer term follow-up to observe post-Electrical A retrospective, case-control study by Shetty et al (2020) showed that a higher percentage of adult patients treated in their facility with adjuvant frequency-specific microcurrent (FSM) in addition to physical rehabilitation for low back pain (LBP) had significantly improved pain and disability when compared to patients in a control group who chose not receive FSM. In their study, they retrospectively reviewed data from the records of 213 patients (167 with LBP and 46 with neck pain) who received FSM in addition to their personalized therapy program along with the records of 78 patients (61 with LBP and 17 with neck pain) who only received their personalized therapy program. Each patient’s rehabilitation protocol was varied and personalized based on their severity of pain and response to movement testing. All patients underwent a minimum rehabilitation treatment of 30 days and a maximum of 90 days with a minimum of 6 supe