Spinal Cord Stimulation Trial Research Articles

Network Meta-analysis and Economic Evaluation of Neurostimulation Interventions for Chronic Non-surgical Refractory back Pain.

Different types of spinal cord stimulation (SCS) have now been evaluated for the management of chronic non-surgical refractory back pain (NSRBP). A direct comparison between the different types of SCS or between closed-loop SCS with conventional medical management (CMM) for patients with NSRBP has not been previously conducted, and therefore, their relative effectiveness and cost-effectiveness remain unknown. The aim of this study was to perform a systematic review, network meta-analysis (NMA) and economic evaluation of closed-loop SCS compared with fixed-output SCS and CMM for patients with NSRBP. Databases were searched to 8th September 2023. Randomised controlled trials of SCS for NSRBP were included. Results of studies were combined using fixed-effect NMA models. A cost-utility analysis was performed from the perspective of the UK National Health Service with results reported as incremental cost per quality-adjusted life-year (QALY). Closed-loop SCS resulted in statistically and clinically significant reductions in pain intensity (mean difference [MD] 32.72 [95% CrI 15.69-49.78]) and improvements in secondary outcomes compared to fixed-output SCS at 6-months follow-up. Compared to CMM, both closed-loop and fixed-output SCS result in statistically and clinically significant reductions in pain intensity (closed-loop SCS vs. CMM MD 101.58 [95% CrI 83.73-119.48]; fixed-output SCS versus CMM MD 68.86 [95% CrI 63.43-74.31]) and improvements in secondary outcomes. Cost-utility analysis shows that closed-loop SCS dominates fixed-output SCS and CMM, and fixed-output SCS also dominates CMM. Current evidence shows that closed-loop and fixed-output SCS provide more benefits and are cost-saving compared to CMM for patients with NSRBP.

10 kHz stimulation as rescue therapy for spinal cord stimulation trial failure or loss of efficacy: A retrospective study.

Spinal cord stimulation (SCS) is currently used for the management of pain of different origin, and since its inception, many waveforms have been developed. Some patients experience no pain relief already during SCS trial, while other patients go through a loss of efficacy due to habituation after a variable period of satisfying pain control. Our retrospective study represents the first report exploring the potential role of 10 kHz stimulation as rescue therapy for patients who did not benefit not only from conventional stimulation but even from other waveforms during SCS trial or follow-up. This study was conducted in Germany; we retrospectively enrolled patients with no pain relief during SCS trial or with loss of efficacy of other waveforms over time; and we recorded visual analogic scale (VAS), Oswestry Disability Index (ODI), and daily opioid consumption expressed as morphine milligram equivalents (MME), right before and 12 months after the switching to 10 kHz simulation. The rate of successful switching to 10 kHz stimulation was comparable in patients enrolled during the SCS trial and during the follow-up (43% vs. 40%, respectively); notably, the highest rate of failed rescue was recorded in case of persistent spinal pain syndrome (PSPS) II. Patients who responded to the switching showed a significant improvement in VAS and ODI after 12 months of treatment compared to baseline (3.6 ± 1.0 vs. 8.2 ± 0.9, p < 0.00001 and 34.0 ± 7.8 vs. 64.3 ± 8.7, p < 0.0001, respectively), whereas there was no reduction in the consumption of opioids in terms of MME (3 (0-16) vs. 5 (0-8.75), p = 0.1003). Rescue therapy with 10 kHz stimulation could be an important strategy to avoid SCS explant in both patients non-responsive during trial or experiencing a loss of efficacy during the years with other waveforms.

Impact of psychosocial factors on the success of neuromodulation treatment for patients with persistent pain

IntroductionSignificant interindividual variability in spinal cord stimulation (SCS) outcomes exists. Due to its high cost and risks of complications, criteria to guide patient selection for SCS trials and their outcomes...

Exploratory evaluation of spinal cord stimulation with dynamic pulse patterns: a promising approach to improve stimulation sensation, coverage of pain areas, and expected pain relief.

The societal burden of chronic pain and the contribution-in-part to the opioid crisis, is a strong motivation to improve and expand non-addictive treatments, including spinal cord stimulation (SCS). For several decades standard SCS has consisted in delivery of tonic pulses with static parameter settings in frequency, pulse width, and amplitude. These static parameters have limited ability to personalize the quality of paresthesia, the dermatomal coverage, and thus may affect SCS efficacy. Further, static settings may contribute to the build-up of tolerance or loss of efficacy of the therapy over time in some patients. We conducted an acute exploratory study to evaluate the effects of SCS using time-dynamic pulses as compared to time-static (conventional tonic) stimulation pulses, with the hypotheses that dynamic pulse SCS may enable beneficial tailoring of the sensation and the patient's expectation for better pain relief with SCS. During a single clinic visit, consented subjects undergoing a standard SCS trial had their implanted leads temporarily connected to an investigational external stimulator capable of delivering time-static and six categories of time-dynamic pulse sequences, each characterized by continuously varying a stimulation parameter. Study subjects provided several assessments while blinded to the stimulation pattern, including: drawing of paresthesia maps, descriptions of sensation, and ratings for comfort and helpfulness to pain relief. Even without optimization of the field location, a majority of subjects rated sensations from dynamic stimulation as better or equal to that of static stimulation for comfortableness and for helpfulness to pain relief. The initial data showed a gender and/or pain dermatomal location related preference to a stimulation pattern. In particular, female subjects and subjects with pain at higher dermatomes tended to rank the sensation from dynamic stimulation better. Dynamic stimulation produced greater pain coverage without optimization; in 70% (9/13) of subjects, maximal pain coverage was achieved with a dynamic stimulation pattern. There was also greater variety in the words used by patients to describe stimulation sensation in the free text and free form verbal descriptions associated with dynamic stimulation. With the same electrode configuration and comparable parameter settings, acute SCS using dynamic pulses produced more positive ratings, expanded paresthesia coverage, and greater variation in sensation as compared to SCS using static pulses, suggesting that dynamic stimulation has the potential to improve capabilities of SCS for the treatment of chronic pain. Further study is warranted. This study was registered at ClinicalTrials.gov under ID NCT02988713, November 2016 (URL: https://clinicaltrials.gov/ct2/show/NCT02988713).

Recovery of Volitional Motor Control and Overground Walking in Participants With Chronic Clinically Motor Complete Spinal Cord Injury: Restoration of Rehabilitative Function With Epidural Spinal Stimulation (RESTORES) Trial-A Preliminary Study.

Spinal cord injury (SCI) is damage to any part of the spinal cord resulting in paralysis, bowel and/or bladder incontinence, and loss of sensation and other bodily functions. Current treatments for chronic SCI are focused on managing symptoms and preventing further damage to the spinal cord with limited neuro-restorative interventions. Recent research and independent clinical trials of spinal cord stimulation (SCS) or intensive neuro-rehabilitation including neuro-robotics in participants with SCI have suggested potential malleability of the neuronal networks for neurological recovery. We hypothesize that epidural electrical stimulation (EES) delivered via SCS in conjunction with mental imagery practice and robotic neuro-rehabilitation can synergistically improve volitional motor function below the level of injury in participants with chronic clinically motor-complete SCI. In our pilot clinical RESTORES trial (RESToration Of Rehabilitative function with Epidural spinal Stimulation), we investigate the feasibility of this combined multi-modal approach in restoring volitional motor control and achieving independent overground locomotion in participants with chronic motor complete thoracic SCI. Secondary aims are to assess the safety of this combination therapy including the off-label SCS usage as well as improving functional outcome measures. To our knowledge, this is the first clinical trial that investigates the combined impact of this multi-modal EES and rehabilitation strategy in participants with chronic motor complete SCI. Two participants with chronic motor-complete thoracic SCI were recruited for this pilot trial. Both participants have successfully regained volitional motor control below their level of SCI injury and achieved independent overground walking within a month of post-operative stimulation and rehabilitation. There were no adverse events noted in our trial and there was an improvement in post-operative truncal stability score. Results from this pilot study demonstrates the feasibility of combining EES, mental imagery practice and robotic rehabilitation in improving volitional motor control below level of SCI injury and restoring independent overground walking for participants with chronic motor-complete SCI. Our team believes that this provides very exciting promise in a field currently devoid of disease-modifying therapies.

Spinal cord stimulation for chronic pain treatment following sacral chordoma resection: illustrative case.

Cancer-related or postoperative pain can occur following sacral chordoma resection. Despite a lack of current recommendations for cancer pain treatment, spinal cord stimulation (SCS) has demonstrated effectiveness in addressing cancer-related pain. A 76-year-old female with a sacral chordoma underwent anterior osteotomies and partial en bloc sacrectomy. She subsequently presented with chronic pain affecting both buttocks and posterior thighs and legs, significantly impeding her daily activities. She underwent a staged epidural SCS paddle trial and permanent system placement using intraoperative neuromonitoring. The utilization of percutaneous leads was not viable because of her history of spinal fluid leakage, multiple lumbosacral surgeries, and previous complex plastic surgery closure. The patient reported a 62.5% improvement in her lower-extremity pain per the modified Quadruple Visual Analog Scale and a 50% improvement in the modified Pain and Sleep Questionnaire 3-item index during the SCS trial. Following permanent SCS system placement and removal of her externalized lead extenders, she had an uncomplicated postoperative course and reported notable improvements in her pain symptoms. This case provides a compelling illustration of the successful treatment of chronic pain using SCS following radical sacral chordoma resection. Surgeons may consider this treatment approach in patients presenting with refractory pain following spinal tumor resection.

Defining the Boundaries of Patient Perception in Spinal Cord Stimulation Programming

ObjectivesRecent developments in spinal cord stimulation (SCS) programming have initiated new modalities of imperceptible stimulation. However, the boundaries of sensory perception are not well defined. The BEnchtop NEuromodulation Following endIng of Trial study aimed to create a map of perceptual threshold responses across a broad range of SCS parameters and programming to inform subperception therapy design. Materials and MethodsThis multicenter study was conducted at seven US sites. A total of 43 patients with low back and/or leg pain who completed a percutaneous commercial SCS trial were enrolled. Test stimulation was delivered through trial leads for approximately 90 minutes before removal. SCS parameters, including amplitude, frequency, pulse width (PW), electrode configuration, cycling, and multifrequency stimulation were varied during testing. Paresthesia threshold (PT), comfort level (CL), perceptual coverage area, and paresthesia quality (through patient selection of keywords) were collected. Differences were evaluated with analysis of variance followed by post hoc multiple comparisons using t-tests with Bonferroni correction. ResultsPT was primarily determined by PW and was insensitive to frequency for constant frequency stimulation (range: 20 Hz–10 kHz; F(1284) = 69.58, p < 0.0001). For all tests, CL was approximately 25% higher than PT. The dominant variable that influenced paresthesia quality was frequency. Sensations described as comfortable and tingling were most common for frequencies between 60 Hz and 2.4 kHz; unpleasant sensations were generally more common outside this range. Increasing distance between active electrodes from 7 mm to 14 mm, or cycling the SCS waveform at 1 Hz, decreased PT (p < 0.0001). Finally, PT for a low-frequency stimulus (ie, 60 Hz) was unaffected by mixing with a sub-PT high-frequency stimulus. ConclusionsIn contrast to previous work investigating narrower ranges, PW primarily influenced PT, independently of frequency. Paresthesia quality was primarily influenced by pulse frequency. These findings advance our understanding of SCS therapy and may be used to improve future novel neuromodulation paradigms.

Efficacy of high-frequency spinal cord stimulation for fibromyalgia syndrome in two cases: case reports

BackgroundReports on the effectiveness of spinal cord stimulation (SCS) for the alleviation of fibromyalgia syndrome (FMS) pain are scarce. We report two cases of effective high-frequency SCS at 1000 Hz against upper- and lower-limb pain in patients with FMS.Case presentationTwo women with widespread pain were diagnosed with FMS and the pain gradually worsened. A 1-week SCS trial was conducted in each patient. In both cases, the patients complained of unpleasant sensations during 10-Hz SCS. However, the pain was alleviated after 1000-Hz stimulation without irritation. Therefore, leads and a generator were implanted, after which they felt almost no pain. Moreover, the dose of the oral medication could be reduced and the patients returned to their daily lives.ConclusionSCS at 1000 Hz may effectively treat pain associated with FMS. Therefore, performing an SCS trial for patients with FMS with intractable pain might be worthwhile.

Procedural education for cancer-related pain in Pain Medicine fellowships: a national program survey

IntroductionCancer-related pain is ubiquitous. Targeted procedural interventions may be an important and underutilized method for improving cancer-related pain and quality of life. The goal of this study was to determine...

Multiphase Spinal Cord Stimulation in Participants With Chronic Back or Leg Pain: Results of the BENEFIT-02 Randomized Clinical Trial

ObjectiveThis study aimed to assess the safety and effectiveness of a new charge-distributed multiphase stimulation paradigm during an extended spinal cord stimulation (SCS) trial. Materials and MethodsThis prospective, multicenter, randomized, single-blind, feasibility study included participants with chronic low back and/or leg pain and baseline numerical rating scale (NRS) for overall pain intensity ≥6. After a successful commercial SCS trial, participants were randomized to multiphase SCS therapy A (approximately 600–1500 Hz) or B (approximately 300–600 Hz), delivered via an investigational external pulse generator and existing leads during an 11-to-12–day testing period. Primary end points were mean NRS change from baseline to final in-office visit for each multiphase therapy and between therapies. Secondary end points included mean NRS change from end of commercial trial to final study visit and incidence of device-related adverse events (AEs). Additional measures included patient-reported outcomes collected at home through electronic watches and written diaries. Power usage was compared between multiphase and commercial therapies. ResultsA total of 122 participants initiated a commercial trial; 77 were randomized to a multiphase arm, and 65 completed the study. Reductions in mean NRS scores from baseline to final study visit were significant for multiphase therapy A and B (−4.3 and −4.7, respectively; both p < 0.0001). There was no statistically significant difference in mean NRS reduction or percent pain relief between multiphase therapies. In an additional analysis, 63.9% of participants reported greater pain relief with multiphase than with commercial SCS therapy in the at-home setting. On average, multiphase required less power than did commercial devices. One non–serious device-related AE was reported, and no infections occurred during the extended trial. ConclusionsMultiphase SCS effectively reduced pain in participants with chronic low back and/or leg pain during a trial, with no unanticipated device-related AEs reported. Future studies should evaluate long-term effectiveness of multiphase stimulation. Clinical Trial RegistrationThe Clinicaltrials.gov registration number for the study is NCT03594266.

Radiographic lead migration in percutaneous spinal cord stimulator trials

IntroductionLead migration during spinal cord stimulator (SCS) trials is relatively neglected in the literature and presents a different set of challenges compared with fully implanted leads. There is no consensus...

Differential target multiplexed spinal cord stimulation using a paddle-type lead placed at the appropriate site for neuropathic pain after spinal cord injury in patients with past spinal surgical histories: study protocol for an exploratory clinical trial

BackgroundNeuropathic pain after spinal cord injury (SCI), both traumatic and non-traumatic, is refractory to various treatments. Spinal cord stimulation (SCS) is one of the neuromodulation therapies for neuropathic pain, although SCS has insufficient efficacy for neuropathic pain after SCI. The reasons are presumed to be inappropriate locations of SCS leads and conventional tonic stimulation itself does not have a sufficient analgesic effect for the pain. In patients with past spinal surgical histories, the cylinder-type leads are likely to be placed on the caudal side of the SCI because of surgical adhesions. Differential target multiplexed (DTM) stimulation is one of the latest new stimulation patterns that is superior to conventional stimulation.MethodsA single-center, open-label, randomized, two-way crossover trial is planned to investigate the efficacy of SCS using DTM stimulation placing a paddle lead at the appropriate site for neuropathic pain after SCI in patients with spinal surgical histories. The paddle-type lead delivers energy more efficiently than a cylinder-type lead. This study consists of two steps: SCS trial (first step) and SCS system implantation (second step). The primary outcome is rates of achieving pain improvement with more than 33% reduction 3 months after SCS system implantation. The secondary outcomes are to be evaluated as follows: (1) effectiveness of DTM and tonic stimulations during the SCS trial; (2) changes of assessment items from 1 to 24 months; (3) relationships between the result of the SCS trial and the effects 3 months after SCS system implantation; (4) preoperative factors associated with a long-term effect, defined as continuing for more than 12 months; and (5) whether gait function improves from 1 to 24 months.DiscussionA paddle-type lead placed on the rostral side of SCI and using DTM stimulation may provide significant pain relief for patients with intractable neuropathic pain after SCI in patients with past spinal surgical histories.Trial registrationJapan Registry of Clinical Trials (jRCT) jRCT 1042220093. Registered on 21 November 2022, and last modified on 6 January 2023. jRCT is approved as a member of the Primary Registry Network of WHO ICTRP.

ID: 218213 Successful Spinal Cord Stimulator Trial in the Visually Impaired

A 72-year-old gentleman was referred to the chronic pain clinic after being deemed a non-surgical candidate for a multilevel lumbar fusion per orthopedic spine surgery. His past medical history is notable for coronary artery disease, diabetes mellitus, obstructive sleep apnea, and blindness in bilateral eyes. The patient has been suffering for years from lower back pain, without red flag symptoms, and had failed multiple treatment modalities, including bilateral sacroiliac joint injections, L3-4, L4-5, and L5-S1 facet blocks. Although he is capable of performing most of his activities of daily living, his blindness unfortunately has been a barrier to both surgical interventions and pain management therapy. After consultation with a chronic pain physician, he was offered a spinal cord stimulator trial. With direct communication between the patient and the spinal cord stimulator company representative, a remote-less algorithm was able to be programmed that allowed for successful mapping of target nerves generating 80% efficacy in pain therapy. A thorough literature review demonstrated a lack of research focus in neuromodulation for patients with disabilities. With tailored guidance this patient achieved adequate pain relief which significantly improved his quality of life during the trial phase. The patient is determined to undergo a permanent spinal cord stimulator placement soon. This case report outlines a successful neuromodulation trial in a visually impaired patient. Ultimately, there is still work to be done to ensure advancements in pain medicine are accessible to all patients regardless of disabilities.

ID: 202060 Successful Spinal Cord Stimulator Trials in Two Patients With Scoliosis

Adult spinal deformity is associated with chronic pain and decreased health-related quality of life. Scoliosis is an abnormal lateral curvature of the spine. Spinal cord stimulation (SCS) may be a good option for scoliosis patients given the neuropathic pain from modification of foramen size due to curvature. Scoliosis can be impactful when performing percutaneous SCS lead placements because the approach relies on radiographic identification of anatomical landmarks. There can be nonalignment of radiographic and electrophysiologic midlines of the spinal cord in spinal deformities, and this deviation can result in SCS failure (1). There are few previous reports on SCS lead placements in patients with scoliosis. We report 2 cases in which SCS trials were successfully performed in the setting of scoliosis.

ID: 207794 Hematoma Complications After Spinal Cord Stimulation Trials and Implantations: A Meta-Analysis

Spinal cord stimulation (SCS) has been successful in the treatment of many chronic pain disorders, including failed back surgery syndrome, angina pectoris, complex regional pain syndrome, peripheral vascular disease, diabetic neuropathy, and nonsurgical low back pain. Although major complications are rare, the consequences can be devastating. For example, epidural hematomas can result in paralysis and typically require urgent surgery to prevent permanent neurologic damage. The aim of this study was to perform a meta-analysis to identify the incidence of neuraxial and non-neuraxial hematomas after SCS trials and implantations.

ID: 220996 Use of Remote Physiological Monitoring to Track Patient Well-Being During the SCS Trial

Spinal cord stimulation (SCS) for chronic intractable back pain is often prescribed after a successful trial period in which a patient demonstrates a sufficient reduction in pain intensity. Currently, the decision of whether to recommend a patient for permanent implant relies upon one or two snapshots from a subjective rating scale (e.g., Numerical Rating Scale, Percent Pain Reduction, Visual Analog Scale). However, subjective rating scales are subject to variability from un-controlled external sources [1]. Additionally, chronic pain is a complex multi-dimensional struggle, and resolution of symptoms may also be manifest via improvements to mental, physical, and social well-being [2]. This research demonstrates proof-of-concept for a remote monitoring system to track and report patient well-being using objective physiologic data collected before, during, and after the SCS trial period.

ID: 215948 Characterization of Real-World Clinical Outcomes in DTM SCS Trials via a Digital Health Platform

Differential Target MultiplexedTM (DTMTM) spinal cord stimulation (SCS) paradigm has been studied via a multicenter randomized clinical trial. Using the Medtronic CareGuideProTM (CGP) digital health platform, we present the real-world evidence (RWE) of DTMTM SCS Trial journey and clinical outcomes.

ID: 223293 Review of Trial to Permanent Outcomes and Explantation Using Spinal Cord Stimulation in VHA

The science of neuromodulation has made many great advances in the recent past. Despite a variety of improvements in technology, usability, ease of use there continues to exist a failure rate leading to surgical explantation of the device.(1) As technology has provided a clear benefit for the field , there continues to remain the elusive goal of optimal patient selection. The causes of explantation have ranged from biologic complications, hardware complications, the need for complex MRI scans , mental health reasons , loss of efficacy, complications, the need for complex MRI scans, mental health issues prior to spinal cord stimulator (SCS) trials.(2,3) It is this last reason , the lack of efficacy due to patient factors which is lacking appropriate evidence. (4) We hypothesized that in our VA population, many of which have been implanted elsewhere, explants may be related to lack of screening for symptoms and/or radiographic evidence of spinal stenosis prior to SCS trial and implant. Given the surgical risk and expense we wanted to use the best evidence to select Veteran patients who would benefit from SCS technology.

ID: 206170 Spinal Cord Stimulator Leads Migrate During Trials Regardless of Anchoring Technique

A spinal cord stimulator (SCS) trial is essential to identify patients who may benefit from the therapy, determine optimal stimulation configuration, and establish the lead position for the permanent implant. During the trial, lead migration is associated with numerous negative consequences, including inadequate programming, false-negative lack of efficacy, and suboptimal lead placement at the time of the permanent implantation. As such, it is critical to define the ideal technique for securing leads to limit migration.

ID: 220962 Inpatient Spinal Cord Stimulation Trial in Patient With Metastatic Colon Cancer Hospitalized for Pain Control

A 55-year-old female with metastatic colon cancer with a soft tissue mass at S1 extending into the vertebral body and posterior epidural space and neuroforamina at L5-S1 was hospitalized for severe lumbar back and bilateral radicular pain. She was initially managed inpatient with escalating dosing of opioid pain medication with minimal improvement of her symptoms. She was unable to ambulate more than 2-3 steps secondary to weakness and pain.