Spinal Cord Stimulation Research Articles

Dorsal Column Spinal Cord Stimulation Attenuates Brain-Spine Connectivity through Locomotion and Visuospatial-Specific Area Activation in Progressive Freezing of Gait

Introduction: Freezing of gait (FOG) is a clinical phenomenon with major life impairments and significant reduction in quality of life for affected patients. FOG is a feature of Parkinson’s Disease and a hallmark of primary progressive freezing of gait (PPGF), currently reclassified as Progressive Supranuclear Palsy-progressive gait freezing (PSP-PGF). The pathophysiology of FOG and particularly PGF, which is a rare degenerative disorder with a progressive natural history of gait decline, are poorly understood. Mechanistically, changes in oscillatory activity and synchronization in frontal cortical regions, the basal ganglia, and the midbrain locomotor region have been reported, indicating that dysrhythmic oscillations and coherence could play a causal role in the pathophysiology of FOG. DBS and SCS have been tested as therapeutic neuromodulation avenues for FOG with mixed outcomes. Methods: We analyzed gait and balance in three patients with PSP-PGF who received percutaneous thoracic spinal cord stimulation (SCS) and utilized magnetoencephalography (MEG), electroencephalography (EEG), and electromyography (EMG) to evaluate functional connectivity between the brain and spine. Results: Gait and balance did not worsen over a 13-month period. This observation was accompanied by decreased beta-band spectral power in the whole brain and particularly in the basal ganglia. This was accompanied by increased functional connectivity in and between the sensorimotor cortices, basal ganglia, temporal cortex, and cerebellum, and a surge in corticomuscular coherence when SCS was paired with visual cues Conclusion: Our results suggest synergistic activity between brain and spinal circuits upon SCS for FOG in PGF, which may have implications for future brain-spine interfaces and closed-loop neuromodulation for patients with FOG.

Spinal cord stimulation induces Neurotrophin-3 to improve diabetic foot disease.

Low-extremity ischemic disease is a common complication in diabetic patients, leading to reduced quality of life and potential amputation. This study investigated the therapeutic effect of spinal cord stimulation (SCS) on patients with diabetic foot disease and a rat model of diabetic foot injury. SCS was applied to patients with diabetic foot disease, with clinical assessments performed before and after therapy. Blood levels of NGF, BDNF, and NT-3 were determined by ELISA. A rat model of diabetic foot injury was established to validate NT-3's role in SCS therapy. SCS therapy improved the condition of patients with diabetic ischemic foot disease and promoted wound healing in the rat model. NT-3 levels significantly increased after SCS therapy in both patients and rats. Recombinant NT-3 administration improved wound healing and re-vascularization in the rat model, while NT-3 neutralization abrogated SCS's therapeutic effect. SCS improves the condition of patients with diabetic ischemic foot disease by inducing NT-3 production. Both SCS and NT-3 supplementation show therapeutic potential for ameliorating diabetic foot disease.

Spinal Cord Stimulation vs Medical Management for Chronic Back and Leg Pain: A Systematic Review and Network Meta-Analysis.

Chronic back and lower extremity pain is one of the leading causes of disability worldwide. Spinal cord stimulation (SCS) aims to improve symptoms and quality of life. To evaluate the efficacy of SCS therapies compared with conventional medical management (CMM). MEDLINE, Embase, and Cochrane Library were systematically searched from inception to September 2, 2022. Selected studies were randomized clinical trials comparing SCS therapies with sham (placebo) and/or CMM or standard treatments for adults with chronic back or leg pain who had not previously used SCS. Evidence synthesis estimated odds ratios (ORs) and mean differences (MDs) and their associated credible intervals (CrI) through bayesian network meta-analysis. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline for network meta-analyses was followed. The primary outcomes were pain-related end points, including pain intensity (measured by visual analog scale) and proportion of patients achieving at least 50% pain relief (responder rate) in the back or leg. Quality of life (measured by EQ-5D index score) and functional disability (measured by the Oswestry Disability Index score) were also considered. A total of 13 studies of 1561 patients were included in the network meta-analysis comparing conventional and novel SCS therapies with CMM across the 6 outcomes of interest at the 6-month follow-up. Both conventional and novel SCS therapies were associated with superior efficacy compared with CMM in responder rates in back (conventional SCS: OR, 3.00; 95% CrI, 1.49 to 6.72; novel SCS: OR, 8.76; 95% CrI, 3.84 to 22.31), pain intensity in back (conventional SCS: MD, -1.17; 95% CrI, -1.64 to -0.70; novel SCS: MD, -2.34; 95% CrI, -2.96 to -1.73), pain intensity in leg (conventional SCS: MD, -2.89; 95% CrI, -4.03 to -1.81; novel SCS: MD, -4.01; 95% CrI, -5.31 to -2.75), and EQ-5D index score (conventional SCS: MD, 0.15; 95% CrI, 0.09 to 0.21; novel SCS: MD, 0.17; 95% CrI, 0.13 to 0.21). For functional disability, conventional SCS was superior to CMM (MD, -7.10; 95% CrI, -10.91 to -3.36). No statistically significant differences were observed for other comparisons. This systematic review and network meta-analysis found that SCS therapies for treatment of chronic pain in back and/or lower extremities were associated with greater improvements in pain compared with CMM. These findings highlight the potential of SCS therapies as an effective and valuable option in chronic pain management.

Spinal cord stimulation in a patient with an implantable cardioverter defibrillator for managing chronic chest pain: a case report and literature review.

The simultaneous use of spinal cord stimulation (SCS) and an implantable cardioverter-defibrillator (ICD) is safe and effective in selected patients with refractory chest pain. Our case highlights successful pain management with SCS without compromising ICD function. Careful patient selection, low device settings, and ongoing monitoring are crucial for achieving optimal outcomes.

A strategic approach of the management of sleep-disordered breathing in multiple system atrophy.

Multiple system atrophy (MSA) is a rare neurodegenerative disorder characterized by autonomic dysfunction associated with a combination of cerebellar, parkinsonian, or pyramidal signs. Sleep-disordered breathing (SDB) such as stridor, obstructive sleep apnea (OSA) and central sleep apnea (CSA) are common in MSA and can impact survival. Several studies have evaluated treatment modalities. However, the optimal strategy often remains unclear in these patients. This review aims to provide an overview of the current evidence on treatment of SDB in MSA. Systematic review of the current literature through combined keyword search in PubMed, Embase, the Cochrane Library and cited references: multiple system atrophy, stridor, sleep apnea syndrome, sleep-disordered breathing, Shy Drager syndrome. Twenty-nine papers were included, with a total of 681 MSA patients with SDB. Treatment modalities are: continuous positive airway pressure (CPAP); tracheostomy; tracheostomy invasive ventilation (TIV); non-invasive positive pressure ventilation (NPPV); adaptive servoventilation (ASV); vocal cord surgery; botulinum toxin injections; oral appliance therapy; cervical spinal cord stimulation; selective serotonin reuptake inhibitors (SSRIs). Conflicting results on survival are found for CPAP therapy. Tracheostomy has a proven survival benefit. Most beneficial outcomes are seen with TIV. CPAP, other types of PAP and tracheostomy can adequately control symptoms of OSA. However, CPAP may exacerbate central sleep apnea. There was a lack of sufficient data regarding ASV or NPPV. Some patients exhibit a floppy epiglottis and require a different approach. In conclusion, due to the complex characteristics of SDB in MSA, an individualized and multidisciplinary approach is mandatory.

Structural changes in the nociceptive system induced by long-term conventional spinal cord stimulation in experimental painful diabetic polyneuropathy

BackgroundClinical studies suggest that long-term conventional spinal cord stimulation (LT-SCS) for painful diabetic peripheral neuropathy (PDPN) is initially effective but may decline in efficacy over time. Preclinical studies indicate that LT-SCS alleviates mechanical hypersensitivity and enhances hind paw blood flow in PDPN rats, suggesting nociceptive system plasticity. This study hypothesized that LT-SCS induces peripheral hind paw small-fiber sprouting and reduces central protein expression of glial and P2X4 brain-derived neurotrophic factor (BDNF) pathway markers.MethodsDiabetes was induced via Streptozotocin injection in 32 rats, with 16 developing PDPN and receiving a quadrupolar lead implant. LT-SCS was applied for 4 weeks, 12 hours per day. Pain behavior was assessed using the Von Frey test for mechanical hypersensitivity and the mechanical conflict avoidance system for motivational aspects of pain. Fiber sprouting was assessed via immunohistochemical analysis of nerve fibers in the hind paw skin. Protein expression in the spinal cord was assessed using western blotting.ResultsLT-SCS increased the baseline threshold of mechanical hypersensitivity in PDPN animals, consistent with previous findings, but showed no effects on motivational aspects of pain. Hind paw tissue analysis revealed significantly increased intraepidermal nerve fiber density of PGP9.5 fibers in LT-SCS animals compared with Sham-SCS animals. Protein analysis showed significantly decreased pro-BDNF expression in LT-SCS animals compared with Sham-SCS animals.ConclusionLT-SCS induces structural changes in both peripheral and central components of the nociceptive system in PDPN animals. These changes may contribute to observed behavioral modifications, elucidating mechanisms underlying LT-SCS efficacy in PDPN management.

Relationship between reticulospinal system sensitization and proprioceptive pathways in the development of dynamic spasticity (ReProDS) post-spinal cord injury: protocol for a prospective, observational cohort study.

Dynamic spasticity (DS) is a common complication post-spinal cord injury (SCI), marked by intermittent increases in muscle tone during postural transitions or movement. Despite its prevalence, high-quality research on DS incidence, risk factors, and underlying mechanisms in SCI patients remains limited. With the growing application of spinal cord stimulation (SCS) for spasticity control, the role of proprioception in DS development has garnered attention. Additionally, advances in diffusion tensor imaging (DTI) allow for the analysis of the reticulospinal tract's (RST) role in postural control among SCI patients. However, the impact of microstructural changes in RST and proprioception on DS following SCI remains unclear. To investigate the relationship between microstructural changes in the RST and proprioceptive circuits in SCI patients, exploring their association with DS and potential predictive factors that influence recovery. This is a 12-month prospective cohort study. The neurophysiological and global functional status of the participants will be assessed. Primary outcomes include DTI indices of RST and proprioception, and spasticity assessment. Secondary outcomes include auditory startle reflex (ASR), H-reflex, shear wave velocity (SWV), overall functional status including spinal cord independence measure, gait analysis, modified Barthel Index, and the 36-item short form health survey. Data will be collected at 1, 3, 6, and 12 months after enrolment. Matched healthy controls will be measured during the same period after recruitment. This study is the first to explore the role of microstructural changes in the RST and proprioception in the assessment and prediction of DS following SCI. The findings aim to enhance theoretical understanding of SCS in spasticity management and to establish pre-treatment criteria for SCS interventions targeting motor function recovery in SCI. ChiCTR2400090724.

Local field potential-based brain-machine interface to inhibit epileptic seizures by spinal cord electrical stimulation.

This study proposes a closed-loop brain-machine interface (BMI) based on spinal cord stimulation to inhibit epileptic seizures, applying a semi-supervised machine learning approach that learns from Local Field Potential (LFP) patterns acquired on the pre-ictal (preceding the seizure) condition.
 
Approach. LFP epochs from the hippocampus and motor cortex are band-pass filtered from 1 to 13 Hz, to obtain the time-frequency representation using the continuous Wavelet transform, and successively calculate the phase lock values (PLV). As a novelty, the Z-score-based PLV normalization using both modified k-means and Davies-Bouldin's measure for clustering is proposed here. Consequently, a generic seizure's detector is calibrated for detecting seizures on the normalized PLV, and enables the spinal cord stimulation for periods of 30 s in a closed-loop, while the BMI system detects seizure events. To calibrate the proposed BMI, a dataset with LFP signals recorded on five Wistar rats during basal state and epileptic crisis was used. The epileptic crisis was induced by injecting pentylenetetrazol (PTZ). Afterwards, two experiments without/with our BMI were carried out, inducing epileptic crisis by PTZ in Wistar rats. 

Main Results. Stronger seizure events of high LFP amplitudes and long time periods were observed in the rat, when the BMI system was not used. In contrast, short-time seizure events of relative low intensity were observed in the rat, using the proposed BMI. The proposed system detected on unseen data the synchronized seizure activity in the hippocampus and motor cortex, provided stimulation appropriately, and consequently decreased seizure symptoms. 

Significance. Low-frequency LFP signals from the hippocampus and motor cortex, and cord spinal stimulation can be used to develop accurate closed-loop BMIs for early epileptic seizures inhibition, as an alternative treatment.

Functional outcomes and healthcare utilization trends in postsurgical and nonsurgical patients following high-frequency (10 kHz) spinal cord stimulation therapy

IntroductionChronic low back pain (CLBP) is the leading cause of disability in the United States and is associated with a steadily increasing burden of healthcare expenditures. Given this trend, it is essential to evaluate interventions aimed at reducing disability and optimizing healthcare utilization (HCU) in affected populations. This study investigates the impact of prior spinal surgery on functional outcomes and HCU patterns following high-frequency (10 kHz) spinal cord stimulation (SCS) therapy.MethodsThis retrospective observational study included 160 subjects who underwent implantation of a 10 kHz SCS device. Participants were divided into surgical and non-surgical cohorts for comparative analysis. Pain relief was assessed using the Numeric Rating Scale (NRS), while disability levels were evaluated using the Oswestry Disability Index (ODI). HCU was examined through the frequency of emergency department (ED) visits, outpatient visits for interventional pain procedures, and opioid consumption measured in morphine milliequivalents (MME).ResultsNo statistically significant differences were observed between the surgical and non-surgical groups regarding pain relief and disability outcomes. Additionally, ED visits and outpatient visits for interventional pain procedures did not show significant differences between the two cohorts.DiscussionThis study represents the first comparative analysis of pain, disability, and HCU trends between surgical and non-surgical populations following 10 kHz SCS therapy. The results suggest that prior spinal surgery may not substantially affect the efficacy of 10 kHz SCS therapy in terms of pain relief, disability reduction, or HCU patterns.

SURG-27. DIRECTIONALLY NON-ROTATING ELECTRIC FIELD THERAPY (DNEFT) DELIVERED THROUGH IMPLANTED ELECTRODES: A NOVEL SURGICAL PLATFORM FOR GLIOBLASTOMA IMMUNOTHERAPY

Abstract BACKGROUND While directionally rotating Tumor Treating Fields (TTF) therapy has garnered considerable clinical interest in recent years, there has been comparatively less focus on directionally non-rotating electric field therapy (dnEFT). OBJECTIVE Here, we explore dnEFT generated through implanted electrodes as a glioblastoma therapeutic platform, with the goal of facilitating clinical translation. METHODS Using custom-designed electrode arrays to study the effect of dnEFT using in vitro and in vivo glioblastoma models. RESULTS In vitro, dnEFT generated using a clinical grade spinal cord stimulator showed anti-neoplastic activity against independent glioblastoma cell lines. In support of the results obtained using the clinical grade electrode, dnEFT delivered through a customized, two-electrode array induced glioblastoma apoptosis. To characterize this effect in vivo, a custom-designed four-electrode array was fabricated such that tumor cells can be implanted into murine cerebrum through a center channel equidistant from the electrodes. After implantation with this array and luciferase expressing murine GL261 glioblastoma cells, mice were randomized to dnEFT or placebo. Relative to placebo treated mice, dnEFT reduced tumor growth (measured by bioluminescence) and prolonged survival (median survival gain of 6.5 days). Analysis of brain sections following dnEFT showed a notable increase in the accumulation of peri-tumoral macrophage/microglia with increased expression of M1 genes (IFNγ, TNFα, IL-6) and decreased expression of M2 genes (CD206, Arg, IL-10) relative to placebo tumors. CONCLUSIONS Our results suggest therapeutic potential in glioblastoma for dnEFT delivered through implanted electrodes as a novel immunotherapy platform, supporting the concept of a proof-of-principle clinical trial using commercially available deep brain stimulator electrodes.

Differential target multiplexed spinal cord stimulation in patients with Persistent Spinal Pain Syndrome Type II: a study protocol for a 12-month multicentre cohort study (DETECT)

IntroductionDifferential target multiplexed spinal cord stimulation (DTM SCS) is a new stimulation paradigm for chronic pain management with the aim of modulating glial cells and neurons in order to rebalance...

Biological and hardware-related spinal cord stimulation complications and their management: A single-center retrospective analysis of the implantation of nonrechargeable implantable pulse generators in different pain conditions

Biological and hardware-related spinal cord stimulation complications and their management: A single-center retrospective analysis of the implantation of nonrechargeable implantable pulse generators in different pain conditions

Bibliometric and visualized analysis of 2014–2024 publications on therapy for diabetic peripheral neuropathy

BackgroundThis research aimed to examine the global developing patterns in the treatment of diabetic peripheral neuropathy (DPN) using a bibliometric analysis of published literature.MethodsWe extracted publication data from papers published between 2014 and 2024 using a specific topic search in the “Web of Science Core Collection” (WoSCC) database. Various metrics, such as the number of papers, citations, authors, countries, institutions, and references, were collected for analysis. To further explore the data, CiteSpace was employed to examine co-citation patterns among authors, identify collaborative efforts between countries and institutions, and uncover emerging trends using burst keywords and reference analysis.ResultsThe study encompassed 2,488 publications that exhibited an increasing trend in annual output. Notably, the journal PAIN, the United States, the Pfizer institution, and the author Feldman, EvaL emerged as the most prolific contributors to this research domain. The term “placebo-controlled trial” was the most prominent burst keyword from 2014 to 2017, whereas “spinal cord stimulation” held this distinction in the recent 5-year span. Furthermore, the publication titled “Pharmacotherapy for neuropathic pain in adults: a systematic review and meta-analysis-2015” demonstrated the highest burst in terms of references.ConclusionThis study is the first to objectively reveal the current hotspots and trends in DPN treatment. The results indicate that drug therapy remains the primary first-line treatment for DPN and that future research on DPN treatment will likely focus on “spinal cord stimulation” and “pain management.” These findings provide valuable insights into DPN treatment.

Case report: Combined transcutaneous spinal cord stimulation and physical therapy on recovery of neurological function after spinal cord infarction

The case of a 37-year-old woman who suffered from spinal cord infarction (SI), resulting in a complete spinal cord injury (AIS A, neurological level T10), and autonomic dysfunction is presented. This study aimed to assess the effect of transcutaneous Spinal Cord Electrical Stimulation (tSCS) on improving motor, sensory, and autonomic function after SI. During the first 8 months, tSCS was applied alone, then, physical therapy (PT) was included in the sessions (tSCS+PT), until completion of 20 months. Compared to baseline, at 20 months, an increase in ISNCSCI motor (50 vs. 57) and sensory scores (light touch, 72 vs. 82; pinprick, 71 vs. 92) were observed. Neurogenic Bladder Symptoms Score (NBSS) changed from 27 at baseline to 17 at 20 months. ISAFSCI scores in sacral autonomic function improved from 0 pts (absent function) to 1 pt. (altered function) indicating better sphincter control. EMG recordings during volitional movements, including overground stepping with 80% of body weight support showed activity in gluteus medialis, tensor fascia latae, sartorius, rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius medialis, indicating a partial reversion of paralysis. RMS analysis indicated higher activity during “tSCS on” compared to “tSCS off” during overground stepping in bilateral rectus femoris (p < 0.001) and gastrocnemius medialis (p < 0.01); and unilateral biceps femoris, and tibialis anterior (p < 0.001). As this is the first report on the use of tSCS in the case of SI, future studies in a case series are warranted.

Studies of the energy characteristics of implantable spinal cord stimulators

Studies of the energy characteristics of implantable spinal cord stimulators

Painful Legs and Moving Toes Syndrome: Case Report and Review

Introduction: Painful legs and moving toes (PLMT) syndrome is a rare movement disorder characterized by defuse lower limb neuropathic pain and spontaneous abnormal, involuntary toe movements. Objective: The objective was to present a rare case of PLMT syndrome with a triggering area in an adult patient due to multilevel discogenic pathology, to make a thorough review of this disorder and to provide a practical approach to its management. Case presentation: A 59-years-old male was admitted to the neurology ward with symptoms of defuse pain in the lower-back and the right leg accompanied by involuntary movements for the right toes intensified by tactile stimulation in the right upper thigh. Magnetic resonance imaging (MRI) revealed a multilevel discogenic pathology of the lumbar and cervical spine, with myelopathy at C5-C7 level. A medication with Pregabalin 300 mg/daily significantly improved both the abnormal toe movements and the leg pain. The clinical effect was constant during the 90-day follow-up without any adverse effects. Conclusion: Painful legs and moving toes (PLMT) is a condition that greatly affects the quality of life of patients, but which still remains less known by clinicians. Spontaneous resolution is rare, and oral medications are the first-line treatment. Pregabalin is a safe and effective treatment option for PLMT that should be considered early for the management of this condition. Other medication interventions, such as botulinum toxin injections, spinal blockade, or non-pharmacological treatment options like spinal cord stimulation, and surgical decompressions, are also recommended when the conservative treatment is ineffective in well-selected patients.

Transcutaneous spinal cord stimulation neuromodulates pre- and postsynaptic inhibition in the control of spinal spasticity.

Aside from enabling voluntary control over paralyzed muscles, a key effect of spinal cord stimulation is the alleviation of spasticity. Dysfunction of spinal inhibitory circuits is considered a major cause of spasticity. These circuits are contacted by Ia muscle spindle afferents, which are also the primary targets of transcutaneous lumbar spinal cord stimulation (TSCS). We hypothesize that TSCS controls spasticity by transiently strengthening spinal inhibitory circuit function through their Ia-mediated activation. We show that 30min of antispasticity TSCS improves activity in post- and presynaptic inhibitory circuits beyond the intervention in ten individuals with traumatic spinal cord injury to normative levels established in 20 neurologically intact individuals. These changes in circuit function correlate with improvements in muscle hypertonia, spasms, and clonus. Our study opens the black box of the carryover effects of antispasticity TSCS and underpins a causal role of deficient post- and presynaptic inhibitory circuits in spinal spasticity.

Spinal cord stimulation combined with exercise in patients diagnosed with persistent spinal pain syndrome. Study protocol for a randomized control trial.

Administration of spinal cord stimulation to individuals with PSPS-T1/2 may induce supraspinal descending activation. Similarly, exercise is recognized as a fundamental aspect of spinal pain management. Studies have demonstrated its impact on neurophysiological factors, including the release of spinal and supraspinal beta-endorphins, which activate μ-opioid receptors. Therefore, the purpose of this study will be to examine the effect of SCS in combination with lumbo-pelvic stability core training on perceived low back pain, quality of life and disability in PSPS-T2 patients. A double-blind randomized clinical trial (RCT) has been designed. All participants will be randomized from a pre-set sequence. The intervention design has been elaborated from the CONSORT guidelines. This study has been registered at Clinicaltrial.gov (NCT06272539). Sample size was calculated using G Power® Sample size software (University of Düsseldorf). The calculation was based on a moderate effect size of 0.7 (partial η2 = 0.70, α = .05, power = 0.95), resulting in a total of 40 patients. Assuming a 30% dropout rate, 52 participants will be recruited in total. Two sessions per week will be scheduled for 8 weeks with a total of 16 sessions. Each work session will have a duration of 60 minutes. The exercise will be adapted according to the phases based on the results already published, limiting in each phase the degrees of flexion and extension of the spine to avoid the risk of electrode migration. Primary outcomes will be functionality, satisfaction, strength, psychosocial variables, quality of life and pain perception.

Restorative Treatments for Cervical Spinal Cord Injury, a Narrative Review.

A narrative review. To summarize relevant data from representative studies investigating upper limb restorative therapies for cervical spinal cord injury. Cervical spinal cord injury (SCI) is a debilitating condition resulting in tetraplegia, lifelong disability, and reduced quality of life. Given the dependence of all activities on hand function, patients with tetraplegia rank regaining hand function as one of their highest priorities. Recovery from cervical SCI is heterogeneous and often incomplete; currently, various novel therapies are under investigation to improve neurological function and eventually better quality of life in patients with tetraplegia. In this article, a narrative literature review was performed to identify treatment options targeting the restoration of function in patients with cervical SCI. Studies were included from available literature based on the availability of clinical data and whether they are applicable to restoration of arm and hand function in patients with cervical SCI. We describe relevant studies including indications and outcomes with a focus on arm and hand function. Different treatment modalities described include nerve transfers, tendon transfers, spinal cord stimulation, functional electrical stimulation, non-invasive brain stimulation, brain-machine interfaces and neuroprosthetics, stem cell therapy, and immunotherapy. As the authors' institution leads one of the largest clinical trials on nerve transfers for cervical SCI, we also describe how patients undergoing nerve transfers are managed and followed at our center. While complete recovery from cervical spinal cord injury may not be possible, novel therapies aimed at the restoration of upper limb motor function have made significant progress toward the realization of complete recovery.

Reoperation Rates and Risk Factors after Spinal Cord Stimulation Revision Surgery

Introduction: Spinal cord stimulation (SCS) is an effective treatment for patients with refractory chronic pain. Despite its efficacy, rates of reoperation after initial implantation of SCS remain high. While revision rates after index SCS surgeries are well reported, less is known about rates and risk factors associated with repeat reoperations. We sought to evaluate patient, clinical, and surgical characteristics associated with repeat reoperation among patients who underwent an initial SCS revision procedure. Methods: We performed a retrospective review of patients who underwent SCS revision surgery performed at a single institution between 2008 and 2022. Patients were stratified by whether they underwent a single revision (SR) or multiple revision (MR) surgeries. Multivariate logistic regression was performed to determine risk factors associated with repeat SCS revision. Kaplan-Meier survival analysis was used to compare rates of devices requiring revision across groups. Results: A total of 54 patients underwent an initial SCS revision. Of these, 15 (28%) underwent a second revision. The most common indication for revision surgery was lead migration (65%). No significant differences were observed in age, body mass index, comorbidities, lead type, and revision indication among the SR and MR groups. On multivariate adjusted analysis, only cervical lead position was significantly associated with repeat reoperation (OR 7.10, 95% CI [1.14, 44.3], p = 0.036). Time to reoperation after a single and MR SCS surgeries did not differ. Conclusions: Among patients who undergo SCS reoperation, a substantial portion requires additional revisions. Cervical lead placement may be associated with a higher risk of repeat revision surgery compared to thoracic lead positioning. Consideration of lead positioning in the decision to perform and undergo reoperation may therefore result in lower revision rates and improved clinical outcomes among SCS patients with MRs.