Healthcare Utilization (HCU) Reduction with High-Frequency (10 kHz) Spinal Cord Stimulation (SCS) Therapy.

Spinal cord stimulation (SCS) is a well-established treatment for patients with chronic pain. With increasing healthcare costs, it is important to determine the benefits of SCS in healthcare utilization (HCU). This retrospective, single-center observational study involved 160 subjects who underwent implantation of a high-frequency (10 kHz) SCS device. We focused on assessing trends in HCU by measuring opioid consumption in morphine milligram equivalents (MME), as well as monitoring emergency department (ED) and office visits for interventional pain procedures during the 12-month period preceding and following the SCS implant. Our results revealed a statistically significant reduction in HCU in all domains assessed. The mean MME was 51.05 and 26.52 pre- and post-implant, respectively. There was a 24.53 MME overall decrease and a mean of 78.2% statistically significant dose reduction (p < 0.0001). Of these, 91.5% reached a minimally clinically important difference (MCID) in opioid reduction. Similarly, we found a statistically significant (p < 0.01) decrease in ED visits, with a mean of 0.12 pre- and 0.03 post-implant, and a decrease in office visits for interventional pain procedures from a 1.39 pre- to 0.28 post-10 kHz SCS implant, representing a 1.11 statistically significant (p < 0.0001) mean reduction. Our study reports the largest cohort of real-world data published to date analyzing HCU trends with 10 kHz SCS for multiple pain etiologies. Furthermore, this is the first and only study evaluating HCU trends with 10 kHz SCS by assessing opioid use, ED visits, and outpatient visits for interventional pain procedures collectively. Preceding studies have individually investigated these outcomes, consistently yielding positive results comparable to our findings.

Durable responses at 24 months with high-frequency spinal cord stimulation for nonsurgical refractory back pain.

OBJECTIVE: The objective of this study was to evaluate the 24-month durability of pain relief, function, quality of life, and safety outcomes for patients with nonsurgical refractory back pain (NSRBP) treated with high-frequency spinal cord stimulation (SCS) within a large, national, multicenter randomized controlled trial (RCT). METHODS: Following the completion of an RCT comparing high-frequency SCS plus CMM with CMM alone for the treatment of NSRBP, patients gave additional consent for a follow-up extension to 24 months. Presented is the cohort analysis of all patients treated with high-frequency SCS following the optional crossover at 6 months. The outcomes assessed to 24 months included responder rate of ≥ 50% pain relief measured according to the visual analog scale [VAS]), disability (Oswestry Disability Index [ODI]), quality of life (EQ-5D 5-level [EQ-5D-5L]), opioid reduction. RESULTS: Of the 125 patients who received a permanent implant, 121 completed the 12-month follow-up, 101 gave additional consent for extended follow-up, and 98 completed the 24-month follow-up. At 24 months after implantation, the mean back pain VAS score was reduced by 73% and the responder rate was 82%. ODI and EQ-5D-5L both improved by at least double the minimal clinically important difference for each measure. No unexpected adverse events were observed, and the rates of serious adverse events (3.4%) and device explantations (4.8%) were low. CONCLUSIONS: The addition of high-frequency SCS to CMM in patients with NSRBP offers profound improvements at 24 months in pain, function, quality of life, and reduced opioid use. This study provides much-needed evidence to inform current clinical practice for managing patients with NSRBP.

Variables associated with nonresponders to high-frequency (10 kHz) spinal cord stimulation.

INTRODUCTION: The use of spinal cord stimulation (SCS) therapy to treat chronic pain continues to rise. Optimal patient selection remains one of the most important factors for SCS success. However, despite increased utilization and the existence of general indications, predicting which patients will benefit from neuromodulation remains one of the main challenges for this therapy. Therefore, this study aims to identify the variables that may correlate with nonresponders to high-frequency (10 kHz) SCS to distinguish the subset of patients less likely to benefit from this intervention. MATERIALS AND METHODS: This was a retrospective single-center observational study of patients who underwent 10 kHz SCS implant. Patients were divided into nonresponders and responders groups. Demographic data and clinical outcomes were collected at baseline and statistical analysis was performed for all continuous and categorical variables between the two groups to calculate statistically significant differences. RESULTS: The study population comprised of 237 patients, of which 67.51% were responders and 32.49% were nonresponders. There was a statistically significant difference of high levels of kinesiophobia, high self-perceived disability, greater pain intensity, and clinically relevant pain catastrophizing at baseline in the nonresponders compared to the responders. A few variables deemed potentially relevant, such as age, gender, history of spinal surgery, diabetes, alcohol use, tobacco use, psychiatric illness, and opioid utilization at baseline were not statistically significant. CONCLUSION: Our study is the first in the neuromodulation literature to raise awareness to the association of high levels of kinesiophobia preoperatively in nonresponders to 10 kHz SCS therapy. We also found statistically significant differences with greater pain intensity, higher self-perceived disability, and clinically relevant pain catastrophizing at baseline in the nonresponders relative to responders. It may be appropriate to screen for these factors preoperatively to identify patients who are less likely to respond to SCS. If these modifiable risk factors are present, it might be prudent to consider a pre-rehabilitation program with pain neuroscience education to address these factors prior to SCS therapy, to enhance successful outcomes in neuromodulation.

Advances in Spinal Cord Stimulation.

Neuromodulation, specifically spinal cord stimulation (SCS), has become a staple of chronic pain management for various conditions including failed back syndrome, chronic regional pain syndrome, refractory radiculopathy, and chronic post operative pain. Since its conceptualization, it has undergone several advances to increase safety and convenience for patients and implanting physicians. Current research and efforts are aimed towards novel programming modalities and modifications of existing hardware. Here we review the recent advances and future directions in spinal cord stimulation including a brief review of the history of SCS, SCS waveforms, new materials for SCS electrodes (including artificial skins, new materials, and injectable electrodes), closed loop systems, and neurorestorative devices.

A Prospective, Randomized Single-Blind Crossover Study Comparing High-Frequency 10,000 Hz and Burst Spinal Cord Stimulation.

OBJECTIVES: Although both high-frequency and burst spinal cord stimulation (SCS) have shown improved efficacy and patient satisfaction compared with conventional tonic stimulation, there are limited data directly comparing the two. This study aimed to compare both high-frequency 10,000 Hz and burst SCS in the same patients in terms of pain relief and satisfaction in those with axial back pain with or without leg pain. MATERIALS AND METHODS: This prospective, single-blind, randomized controlled trial was conducted at an outpatient pain clinic within an academic medical center. Participants were randomly allocated to one of two groups in which they trialed either burst or high-frequency 10,000 Hz SCS over five days, followed by a 24- to 48-hour washout period with no stimulation, and the alternative therapy over the remaining four days. Visual analog scale (VAS) scores were collected immediately before and after both therapy trials. Secondary end points included percentage change in VAS score and patient preference. RESULTS: Of 25 participants, those receiving burst followed by high-frequency SCS (n = 11) had a mean VAS difference of 4.73 after the first trial period and 2.86 after the second. Of those receiving high-frequency followed by burst SCS (n = 14), mean VAS difference after the first trial period was 4.00 and 1.93 after the second trial period. Four participants were withdrawn owing to lead migration. Both therapies showed statistically significant differences in pre- minus post-VAS scores and percent relief. There were no significant differences in carryover or treatment effects between the two groups. There was a statistically significant association between trial sequence and stimulator type implanted because the first stimulator trialed was more likely to be chosen. CONCLUSIONS: There were no observed differences in VAS pain score decrease when comparing burst and high-frequency 10,000 Hz SCS programming therapies. Patient preference followed an order effect, favoring the first programming therapy in the trial sequence.

Treatment of nonsurgical refractory back pain with high-frequency spinal cord stimulation at 10 kHz: 12-month results of a pragmatic, multicenter, randomized controlled trial.

OBJECTIVE: Spinal cord stimulation (SCS) at 10 kHz (10-kHz SCS) is a safe and effective therapy for treatment of chronic low-back pain. However, it is unclear from existing evidence whether these findings can be generalized to patients with chronic back pain that is refractory to conventional medical management (CMM) and who have no history of spine surgery and are not acceptable candidates for spine surgery. The authors have termed this condition "nonsurgical refractory back pain" (NSRBP) and conducted a multicenter, randomized controlled trial to compare CMM with and without 10-kHz SCS in this population. METHODS: Patients with NSRBP, as defined above and with a spine surgeon consultation required for confirmation, were randomized 1:1 to patients undergoing CMM with and without 10-kHz SCS. CMM included nonsurgical treatment for back pain, according to physicians' best practices and clinical guidelines. Primary and secondary endpoints included the responder rate (≥ 50% pain relief), disability (Oswestry Disability Index [ODI]), global impression of change, quality of life (EQ-5D-5L), and change in daily opioid use and were analyzed 3 and 6 months after randomization. The protocol allowed for an optional crossover at 6 months for both arms, with observational follow-up over 12 months. RESULTS: In total, 159 patients were randomized; 76 received CMM, and 69 (83.1%) of the 83 patients who were assigned to the 10-kHz SCS group received a permanent implant. At the 3-month follow-up, 80.9% of patients who received stimulation and 1.3% of those who received CMM were found to be study responders (primary outcome, ≥ 50% pain relief; p < 0.001). There was also a significant difference between the treatment groups in all secondary outcomes at 6 months (p < 0.001). In the 10-kHz SCS arm, outcomes were sustained, including a mean 10-cm visual analog scale score of 2.1 ± 2.3 and 2.1 ± 2.2 and mean ODI score of 24.1 ± 16.1 and 24.0 ± 17.0 at 6 and 12 months, respectively (p = 0.9). In the CMM arm, 74.7% (56/75) of patients met the criteria for crossover and received an implant. The crossover arm obtained a 78.2% responder rate 6 months postimplantation. Five serious adverse events occurred (procedure-related, of 125 total permanent implants), all of which resolved without sequelae. CONCLUSIONS: The study results, which included follow-up over 12 months, provide important insights into the durability of 10-kHz SCS therapy with respect to chronic refractory back pain, physical function, quality of life, and opioid use, informing the current clinical practice for pain management in patients with NSRBP.

Interventional Procedures for Vertebral Diseases: Spinal Tumor Ablation, Vertebral Augmentation, and Basivertebral Nerve Ablation-A Scoping Review.

Low back pain is consistently documented as the most expensive and leading cause of disability. The majority of cases have non-specific etiologies. However, a subset of vertebral diseases has well-documented pain generators, including vertebral body tumors, vertebral body fractures, and vertebral endplate injury. Over the past two decades, specific interventional procedures targeting these anatomical pain generators have been widely studied, including spinal tumor ablation, vertebral augmentation, and basivertebral nerve ablation. This scoping review summarizes safety and clinical efficacy and discusses the impact on healthcare utilization of these interventions. Vertebral-related diseases remain a top concern with regard to prevalence and amount of health care spending worldwide. Our study shows that for a subset of disorders related to the vertebrae, spinal tumor ablation, vertebral augmentation, and basivertebral nerve ablation are safe and clinically effective interventions to decrease pain, improve function and quality of life, and potentially reduce mortality, improve survival, and overall offer cost-saving opportunities.

Retrospective Analysis of Real-World Outcomes of 10 kHz SCS in Patients with Upper Limb and Neck Pain.

BACKGROUND: Patients living with chronic upper limb and neck (ULN) pain are reliant on often ineffective therapies as they face limited options for effective long-term treatment. OBJECTIVE: Prospective clinical studies have demonstrated that high-frequency spinal cord stimulation at 10 kHz (10 kHz SCS) is effective in treating chronic pain in multiple etiologies including ULN pain. This study aimed at validating the findings from clinical studies on ULN in a real-world cohort. STUDY DESIGN: A retrospective, observational review. SETTING: A multicenter review between April 2016 and August 2019. PATIENTS AND METHODS: Anonymized data were extracted from a real-world database of 47 consecutive patients aged ≥18 years of age with chronic upper limb and/or neck pain who were trialed and permanently implanted with 10 kHz SCS. Patient-reported pain relief, quality of life, function, sleep and medication use were extracted from anonymised patient records where available. Responder rates, defined as the proportion of patients with at least 50% pain relief at the end of trial and the last visit after implantation, were calculated. RESULTS: All patients reported successful response (≥50% pain relief) at the end of trial and >75% patients continued to respond to the therapy at the last follow-up period. Majority (72%) of patients reported improvement in function, about half of the patients (53%) reported improvement in sleep and one-third of the patients (36%) reported reducing their medication at last follow-up. CONCLUSION: 10 kHz SCS provides durable pain relief to patients with chronic upper limb and neck pain.

Reducing Radiation Exposure in Lumbar Transforaminal Epidural Steroid Injections with Pulsed Fluoroscopy: A Randomized, Double-blind, Controlled Clinical Trial.

BACKGROUND: Fluoroscopy-guided lumbar transforaminal epidural steroid injections (L-TFESI) result in radiation exposure that carries risks to patients, physicians, and procedural staff. OBJECTIVE: We aim to evaluate the feasibility of using pulsed fluoroscopy to safely reduce radiation exposure during L-TFESI. STUDY DESIGN: This is a prospective, double-blind, randomized controlled trial. SETTING: This study took place in a single-center, academic, outpatient interventional pain management clinic. METHODS: Patients undergoing L-TFESI were randomly assigned to either continuous mode fluoroscopy (high-dose), pulsed fluoroscopy with 8 pulses per second (medium-dose), or pulsed fluoroscopy with one pulse per second (low-dose). Data on radiation doses and other clinical and demographic factors were also collected. RESULTS: In total, 231 cases were analyzed in the high-dose group (n = 81), medium-dose group (n = 72), and low-dose group (n = 78). Mean radiation effective dose (µSv) was 121 in the high-dose group, 57.9 in the medium-dose group, and 34.8 in the low-dose group (P < 0.001). The incidence of inadequate image quality in the pulsed groups was 6% (9/150). The body mass index (BMI, mean ± SD) was significantly higher in patients with inadequate image quality (37.3 ± 7.2) than with adequate quality (30.5 ± 7.2, P = 0.005). LIMITATIONS: Radiation doses were measured using the meter on C-arm fluoroscopes rather than by direct measurement. CONCLUSIONS: The use of pulsed fluoroscopy during L-TFESI resulted in radiation dose reduction of up to 72.1% without causing any significant adverse events. Pulsed fluoroscopy should be considered as an initial fluoroscopic setting for L-TFESI to reduce radiation exposure. KEY WORDS: Radiation, epidural, fluoroscopy, injection, exposure, pulse.