Treatment of Déjerine-Roussy syndrome pain with scrambler therapy

The Use of Scrambler Therapy in Treating Chronic Pain Syndromes: A Systematic Review

BACKGROUND

Scrambler therapy (ST) is a noninvasive method of transcutaneous neuromodulation that has 510(K) clearance from the United States Food and Drug Administration for treating acute pain, postoperative pain, and intractable chronic pain. Since its inception, ST has been used to treat many chronic pain syndromes in a variety of patient populations. We synthesized the available literature for ST to delineate its overall evidence basis.

MATERIALS AND METHODS

We performed a systematic review based on conventional Preferred Reporting Items for Systematic Reviews and Meta-Analyses methods by surveying multiple data sources from January 1950 through October 2021. Two review authors, independently and in a standardized, unblinded fashion, conducted a systematic review to identify relevant studies and extract the necessary outcome measures. A conservative search strategy was implemented to identify all ST studies for the treatment of chronic pain syndromes. Primary outcome parameters collected were analgesic benefit, adverse effects, and other metrics such as sensorimotor testing.

RESULTS

A total of 21 studies met the final criteria for study inclusion and comprised randomized controlled trials (n = 8), prospective observational studies (n = 10), and retrospective cohort studies (n = 3). Nearly all the reported studies explored the use of ST for the treatment of neuropathic pain, with chemotherapy-induced peripheral neuropathy being the most studied condition. Most studies were limited by small cohorts but reported ST being safe, well tolerated, and providing clinically meaningful pain reduction. The duration of posttreatment follow-up ranged from ten to 14 days (concordant with completion of typical ST protocols) to three months. Secondary benefits such as medication reduction and improvement of sensory and motor symptoms were noted by some studies.

CONCLUSIONS

ST is regarded as a safe intervention with potential for significant analgesic benefit for neuropathic pain conditions. Although the available evidence is most robust for treating chemotherapy-induced peripheral neuropathy, ST has also been shown to be effective in treating other neuropathic pain syndromes. Evidence for ST use in nociceptive pain conditions is limited but appears promising. The favorable safety profile and increasing evidence basis for ST warrant more extensive recognition and consideration for use in clinical care.

Safety of Scrambler Therapy: A Systematic Review of Complications and Adverse Effects

OBJECTIVE

The objective was to qualitatively synthesize all reported cases of complications, adverse effects, side effects, or harms arising from the use of scrambler therapy (ST).

METHODS AND DESIGN

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The PubMed, Embase, Scopus, Web of Science, United States National Library of Medicine clinical trials registry, and Cochrane Central Register of Controlled Trials databases were searched from database inception to December 10, 2021. Case reports/series, abstracts, retrospective studies, and prospective studies (e.g., open-label trials, randomized controlled trials) pertaining to ST and any description of a complication, adverse effect, side effect, or harm were screened. The search protocol was developed a priori and registered via the International Prospective Register of Systematic Reviews (PROSPERO ID: CRD42021291838).

RESULTS

A total of six RCTs, 19 prospective open-label trials, and 11 case series / case reports met the inclusion criteria, comprising 1,152 total patients. Two patients experienced contact dermatitis, and one patient reported minor ecchymosis that resolved without intervention. This yielded a composite complication rate of 0.26% (3/1,152). There were zero reported serious adverse events.

CONCLUSIONS

When used in accordance with the treatment protocols described by the United States Food and Drug Administration and device manual, ST is associated with a reported composite complication rate that is orders of magnitude lower than those of invasive neuromodulation devices. ST neuromodulation is a safe alternative for patients who cannot undergo invasive neuromodulation device implantation because of either risk or preference.

Scrambler Therapy for the Treatment of Multiple System Atrophy-Parkinsonian Subtype Pain: A Case Report

The management of pain in patients with multiple system atrophy (MSA) is often inadequate, and treatments commonly result in adverse effects. A 63-year-old man with the parkinsonian subtype of MSA presented with bilateral neck, shoulder, upper extremity, lower extremity, and low back pain of 6 years' duration. His baseline pain was 5 of 10 with flares to 10 of 10. After 4 35-minute scrambler therapy (ST) treatments, his pain was reduced to 0 of 10. His pain relief after 4 ST sessions lasted for 6 weeks. No complications or adverse effects occurred. ST deserves further study for patients with atypical parkinsonism.

Use of Scrambler Therapy in the Treatment of Amyloidosis Neuropathic Pain

Background: Scrambler therapy (ST) is a relatively new neuromodulation technique that is useful in treatment of medication-resistant pain syndromes, including chemotherapy-induced peripheral neuropathy and other chronic pain syndromes. Amyloidosis commonly leads to peripheral neuropathy, and although the mechanism is unclear, it is possibly related to amyloid deposits on the nerve. Case Presentation: In this case presentation, we describe the novel use of ST for a patient with 13 years of neuropathic pain related to amyloidosis and worsened by chemotherapy. The patient reported bilateral hand pain with burning and aching and bilateral numbness on the soles of her feet. Her upper extremities were treated with 4 days of 40 minute ST treatment sessions providing reduction in her pain scores to zero. Discussion: Current therapy for amyloid peripheral neuropathy aims at treating the underlying condition, and then medical management with gabapentinoids. This is first case presentation showing successful treatment with ST.