The impact of scrambler therapy on pain and quality of life for chemotherapy-induced peripheral neuropathy: A pilot study

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating disturbance among patients who received chemotherapy, with no effective treatment available. Scrambler therapy (ST) is a noninvasive treatment capable of improving multiple quality-of-life symptoms beyond pain. We aimed to evaluate the efficacy of ST for pain and nonpain symptoms related to CIPN.

METHODS

Ten patients with moderate to severe CIPN symptoms for >3 months were enrolled in a single-arm trial of ST for 10 daily sessions. CIPN-related symptoms were measured throughout the treatment period and up to 6 months thereafter.

RESULTS

The worst pain was reduced by 6 months (p = 0.0039). QST demonstrated the greatest improvement in pressure of 60 g (p = 0.308, Cohen's d = 0.42) and cold temperature threshold of 2.5°C (p = 0.9375, Cohen's d = 0.51) in the gastrocnemius area. Symptoms of numbness, tingling, trouble walking, and disturbed sleep had significant improvements at 6 months. Pain medication use decreased by 70% at the end of treatment and by 42% at 6 months. Patient satisfaction was high (82%) and no adverse events with ST treatment were reported.

CONCLUSIONS

The results of this pilot trial support the use of ST by demonstrating improvement in multiple domains of quality of life for CIPN patients during an extended follow-up of 6 months. However, further large-scale studies are needed to confirm our findings.

Scrambler Therapy for Patients With Complex Regional Pain Syndrome: A Case Series

Complex regional pain syndrome is a chronic debilitating pain disorder that is difficult to manage, in part due to its heterogeneous clinical presentation and lack of clearly defined pathophysiology. Patients usually require a multidisciplinary approach to treatment, which can entail pharmacotherapy, physical therapy, behavioral therapy, and interventional pain procedures, such as sympathetic nerve blocks, spinal cord stimulation, and dorsal root ganglion stimulation. However, many patients continue to experience pain refractory to these multimodal strategies. Scrambler therapy (ST) is a noninvasive method of neuromodulation that is applied through cutaneous electrodes, and can alleviate chronic neuropathic pain by stimulating C-fibers and replacing endogenous pain signals with synthetic non-nociceptive signals. Although the use of ST has been reported for several types of refractory central and peripheral neuropathic pain, there is a paucity of data regarding the use of ST for complex regional pain syndrome. We present two patients with complex regional pain syndrome of the right lower extremity, who each underwent ST and experienced significant pain relief and improvement in function and quality of life.

Complex Regional Pain Syndrome: Evidence-Based Advances in Concepts and Treatments

PURPOSE OF REVIEW

This review presents the most current information about the epidemiology of complex regional pain syndrome (CRPS), classification and diagnostic criteria, childhood CRPS, subtypes, pathophysiology, conventional and less conventional treatments, and preventive strategies.

RECENT FINDINGS

CRPS is a painful disorder with multifactorial pathophysiology. The data describe sensitization of the central and peripheral nervous systems, inflammation, possible genetic factors, sympatho-afferent coupling, autoimmunity, and mental health factors as contributors to the syndrome. In addition to conventional subtypes (type I and type II), cluster analyses have uncovered other proposed subtypes. Prevalence of CRPS is approximately 1.2%, female gender is consistently associated with a higher risk of development, and substantial physical, emotional, and financial costs can result from the syndrome. Children with CRPS seem to benefit from multifaceted physical therapy leading to a high percentage of symptom-free patients. The best available evidence along with standard clinical practice supports pharmacological agents, physical and occupational therapy, sympathetic blocks for engaging physical restoration, steroids for acute CRPS, neuromodulation, ketamine, and intrathecal baclofen as therapeutic approaches. There are many emerging treatments that can be considered as a part of individualized, patient-centered care. Vitamin C may be preventive. CRPS can lead to progressively painful sensory and vascular changes, edema, limb weakness, and trophic disturbances, all of which substantially erode healthy living. Despite some progress in research, more comprehensive basic science investigation is needed to clarify the molecular mechanisms of the disease so that targeted treatments can be developed for better outcomes. Incorporating a variety of standard therapies with different modes of action may offer the most effective analgesia. Introducing less conventional approaches may also be helpful when traditional treatments fail to provide sufficient improvement.

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 noncancer neuropathic pain: a focused review

PURPOSE OF REVIEW

Therapeutic methods for neuropathic are limited; available drugs can be inadequate or have adverse effects that compromise quality of life. Interest has grown in alternatives to pharmacologic therapy for neuropathic pain. We present a focused review of the literature about the relatively novel noninvasive, nonpharmacologic electrocutaneous nerve stimulation technique called scrambler therapy for treating noncancer neuropathic pain.

RECENT FINDINGS

Neuromodulation techniques targeting peripheral sites have changed rapidly in recent years. Several clinical studies have demonstrated the analgesic effect of scrambler therapy after 10 sessions of treatment for various types of pain. Although scrambler therapy was originally used for cancer pain, its indications have broadened to postoperative pain, chemotherapy-induced peripheral neuropathy, postherpetic neuralgia, low back pain, diabetic neuropathy, complex regional pain syndrome and central pain syndrome. That said, some of the studies are controversial owing to their small sample size, lack of appropriate scrambler therapy protocol and possible lack of experience of the operators.

SUMMARY

We present the historical perspective, mechanism of action and trial outcomes of scrambler therapy, representing an avenue for managing neuropathic pain without drugs. Well designed phase II/III clinical trials must be conducted to confirm the positive findings reported using scrambler therapy technology. If validated, scrambler therapy could be a game changer.

Efficacy and Effectiveness of Physical Agent Modalities in Complex Regional Pain Syndrome Type I: A Scoping Review

Complex regional pain syndrome type I (CRPS-I) is a rare condition with huge variability in triggering factors and clinical scenarios. The complexity of the pathophysiology of this condition fosters the proposal of several therapeutic options with different mechanisms of action in both research and clinical practice. An interdisciplinary and multimodal approach, including pharmacological and non-pharmacological interventions, particularly physical therapy, is recommended by international guidelines, but the benefits and harms of available interventions are poorly known. In this scoping review, the clinical rationale for use of physical agent modalities for patients with CRPS-I will be presented. We found 10 studies addressing the role of electromagnetic field therapy, electrotherapy, and laser therapy. Our findings suggest that physical therapy modalities, in particular transcutaneous electrical nerve stimulation (TENS) and pulsed electromagnetic field therapy (PEMF), may contribute to reduce pain and improve function in patients with CRPS-1.

Scrambler therapy: A ray of hope for refractory chemotherapy-induced peripheral neuropathy

Scrambler therapy (ST) is a novel noninvasive modality for treatment of chronic neuropathic and cancer pain using 5 artificial neurons. The principle with Scrambler Therapy is that synthetic "non-pain" information is transmitted by C fiber surface receptors. Chemotherapy-induced peripheral neuropathy can markedly deteriorate patient's quality of life and can also negatively affect compliance with the anticancer treatment. Chronic neuropathic pain presents a therapeutic challenge if resistant to pharmacological management opioids and other types of treatments. We have described here successful use of scrambler therapy in three cases of chemotherapy-induced peripheral neuropathy.

Mechanism-specific rehabilitation management of complex regional pain syndrome: Proposed recommendations from evidence synthesis

STUDY DESIGN

Narrative review.

INTRODUCTION

There are a variety of treatments with demonstrated effectiveness for the management of complex regional pain syndrome (CRPS). However given the variability in symptom presentation in this population, therapists may be unsure what treatments would be most effective for individual clients.

PURPOSE OF THE STUDY

To present a brief synthesis of the literature and propose a rehabilitation version of a mechanism-specific management algorithm to guide personalized treatment of CRPS.

METHODS

A systematic search of the literature was conducted to identify all randomized controlled trials, systematic reviews, and clinical practice guidelines addressing rehabilitation of CRPS. Results were reviewed independently by 2 reviewers and final selection of articles was reached by consensus, Data was extracted using standardized forms, and a single rater gave quality ratings. Both reviewers then used the extracted data to present a synthesis of the evidence categorized by the proposed mechanisms of effect.

RESULTS

A total of 111 articles were retrieved and reviewed for inclusion; 49 were selected for data extraction. A synthesis of the key recommendations was compiled into a rehabilitation-specific version of the mechanism-based management algorithm proposed by Gierthmühlen et al (2014).

CONCLUSIONS

Consideration of mechanism-appropriate rehabilitation interventions may assist therapists to select the most appropriate and effective treatments from the body of evidence supporting rehabilitation of CRPS.

Successful Treatment of Scar Pain with Scrambler Therapy

Scar pain from thoracotomy, hepatectomy, or similar operations is distressing and difficult to treat. Scrambler Therapy is a novel form of superficial neuromodulation that has been effective in treating different types of neuropathic pain. We report here two cases of dramatic relief from disabling scar pain with one or two sessions of Scrambler Therapy.

A Pilot Randomized Sham-Controlled Trial of MC5-A Scrambler Therapy in the Treatment of Chronic Chemotherapy-Induced Peripheral Neuropathy (CIPN)

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) affects 30% to 40% of patients with cancer with long-lasting disability. Scrambler therapy (ST) appeared to benefit patients in uncontrolled trials, so we performed a randomized sham-controlled Phase II trial of ST.

METHODS

The primary end point was "average pain" after 28 days on the Numeric Rating Scale. Each received ten 30-minute sessions of ST on the dermatomes above the painful areas, or sham treatment on the back, typically at L3-5 where the nerve roots would enter the spinal cord. Outcomes included the Brief Pain Inventory (BPI)-CIPN and the EORTC CIPN-20 scale. Patients were evaluated before treatment (day 0), day 10, and days 28, 60, and 90.

RESULTS

Data regarding pain as a primary outcome were collected for 33 of the 35 patients. There were no significant differences between the sham and the "real" ST group at day 10, 28, 60, or 90, for average pain, the BPI, or EORTC CIPN-20. Individual responses were noted during the ST treatment on the real arm, but most dissipated by day 30. There was improvement in the sensory subscale of the CIPN-20 at 2 months in the "real" group (P = .14). All "real" patients wanted to continue treatment if available.

DISCUSSION

We observed no difference between sham and real ST CIPN treatment. Potential reasons include at least the following: ST does not work; the sham treatment had some effect; small sample size with heterogeneous patients; misplaced electrodes on an area of nonpainful but damaged nerves; or a combination of these factors.

Inside the Scrambler Therapy, a Noninvasive Treatment of Chronic Neuropathic and Cancer Pain: From the Gate Control Theory to the Active Principle of Information

Scrambler therapy (ST) is an electro-analgesia therapy for the noninvasive treatment of chronic neuropathic and cancer pain based on a new generation of medical device that uses 5 artificial neurons and is based on a novel theoretical model the differs from gate control theory. The active principle with Scrambler Therapy is such that synthetic "non-pain" information is transmitted by C fiber surface receptors. This is a different theoretical mechanism than the traditional electric stimulation of A-Beta fibers to produce paresthesia and/or block the conduction of nerve fibers to produce an analgesic effect, that is, via TENS (transcutaneous electrical nerve stimulation) machines. Scrambler therapy was developed to treat chronic neuropathic pain and cancer pain resistant to opioids and other types of treatments. The goal of Scrambler Therapy is to eliminate pain during treatment and allow for long-lasting analgesia after a series of 10 to 12 consecutive treatments performed over a 2-week period. The aim of this review is to clarify the underlying theory of Scrambler Therapy and describe the appropriate usage method that maximizes its effectiveness while reducing bias and deepen the explanation of the artificial neuron technology associated with Scrambler Therapy.

Scrambler therapy efficacy and safety for neuropathic pain correlated with chemotherapy-induced peripheral neuropathy in adolescents: A preliminary study

PURPOSE

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of chemotherapy, in need of effective treatment. Preliminary data support the efficacy of scrambler therapy (ST), a noninvasive cutaneous electrostimulation device, in adults with CIPN. We test the efficacy, safety, and durability of ST for neuropathic pain in adolescents with CIPN.

PATIENTS AND METHODS

We studied nine pediatric patients with cancer and CIPN who received ST for pain control. Each patient received 45-min daily sessions for 10 consecutive days as a first step, but some of them required additional treatment.

RESULTS

Pain significantly improved comparing Numeric Rate Scale after 10 days of ST (9.22 ± 0.83 vs. 2.33 ± 2.34; P < 0.001) and at the end of the optimized cycle (EOC) (9.22 ± 0.83 vs. 0.11 ± 0.33, P < 0.001). The improvement in quality of life was significantly reached on pain interference with general activity (8.67 ± 1.66 vs. 3.33 ± 2.12, P < 0.0001), mood (8.33 ± 3.32 vs. 2.78 ± 2.82, P < 0.0005), walking ability (10.00 vs. 2.78 ± 1.22, P < 0.0001), sleep (7.56 ± 2.24 vs. 2.67 ± 1.41, P < 0.001), and relations with people (7.89 ± 2.03 vs. 2.11 ± 2.03, P < 0.0002; Lansky score 26.7 ± 13.2 vs. 10 days of ST 57.8 ± 13.9, P < 0.001; 26.7 ± 13.2 vs. EOC 71.1 ± 16.2, P < 0.001).

CONCLUSION

Based on these preliminary data, ST could be a good choice for adolescents with CIPN for whom pain control is difficult. ST caused total relief or dramatic reduction in CIPN pain and an improvement in quality of life, durable in follow-up. It caused no detected side effects, and can be retrained successfully. Further larger studies should be performed to confirm our promising preliminary data in pediatric patients with cancer.

Scrambler Therapy for the Treatment of Chronic Central Pain: A Case Report

Central pain syndromes affect several million people worldwide. A 52-year-old woman had central pain manifest as burning pain from her left foot to the knee for 12 years after treatment for a medullary cavernoma diagnosed after a right-sided brainstem bleeding episode. All this time, her baseline pain was 5-6/10 with spikes to 9-10/10 during activity. She underwent 10 daily Scrambler (Calmare) Therapy treatments (GEOMC, Inc, Seoul, Korea) with reduction in her pain from 9-10/10 to 0-0.5/10, then 5 more sessions a month later. Her baseline pain stayed at 2/10 at 140 days with spikes only to 5/10, and no additional medications. Scrambler (Calmare) Therapy deserves further study in central pain.

Scrambler Therapy for the Treatment of Chronic Post-Mastectomy Pain (cPMP)

Chronic post-mastectomy pain (cPMP), including post-lumpectomy pain, is common with no established ways of treatment. We treated three consecutive patients referred with cPMP with scrambler therapy (ST), a non-invasive electrical neurocutaneous stimulation. Treatment was given across the area of pain following the dermatomes for 45 minutes daily, for several consecutive days until relief, and then was repeated as needed. The ST MC5A device synthesizes 16 different waveforms that resemble action potentials, delivered to the surface receptors of the c-fibers, to send “non-pain” information along the damaged pathways to reduce central sensitization. All three had marked (over 75%) and sustained (months) reduction of allodynia, hyperalgesia, and pain. All reported marked improvements in their quality of life and normal function. One woman was able to stop chronic opioid use. No side effects were observed.

Scrambler therapy is a promising way to relieve cancer and other types of neuropathic pain, and may be helpful in cPMP. Further prospective trials are warranted.