Early Functional Outcomes in Low Back Pain Subjects with a Novel Interspinous Fusion Device: REFINE Study 6-Month Results.

Purpose: Lumbar interlaminar decompression with interspinous fixation is an established safe and effective treatment for spinal stenosis. Early maintenance of improvements in pain intensity and function are critical for durability of symptom relief. The purpose of this study was to investigate the efficacy of minimally invasive treatments for low back pain during the early period after treatment and their utility in setting the course for longer term success. Patients and Methods: This study utilized patient evaluations at 3- and 6-months following treatment and is part of an actively enrolling, institutional review board (IRB) approved, single-arm, multicenter, prospective, open-label 12-month study. Clinical efficacy was assessed primarily using the change from baseline in Oswestry Disability Index (ODI), Visual Analog Scale (VAS) of the back and leg pain during walking and standing, and Zurich Claudication Questionnaire (ZCQ), and secondarily using the Patient Global Impression of Change (PGIC) and Patient-Reported Outcomes Measurement Information System (PROMIS) 29 v2.1. The safety endpoints were the adverse events and reoperations or revisions at the index level(s). Results: At 6-month post-op, 76%, 62%-64%, and 64% of patients demonstrated clinical meaningful, and statistically significant improvement in their pain as defined by ZCQ, VAS (back and leg), and ODI, respectively. In addition, 78% of patients noted improvement in PGIC. Two procedure-related adverse events were noted which fully resolved without surgical intervention. Conclusion: This 6-month interim analysis at 42% enrollment of patients was conducted to determine prolonged safety and efficacy of the interspinous fusion device. Our analysis showed a sustained improvement in clinical efficacy, and safety endpoints, when compared to the 3-months evaluations, across both interventional pain and neurosurgery specialties.

Long-term efficacy of high-frequency (10 kHz) spinal cord stimulation for the treatment of painful diabetic neuropathy: 24-Month results of a randomized controlled trial.

AIMS: To evaluate the long-term efficacy of high-frequency (10 kHz) spinal cord stimulation (SCS) for treating refractory painful diabetic neuropathy (PDN). METHODS: The SENZA-PDN study was a prospective, multicenter, randomized controlled trial that compared conventional medical management (CMM) alone with 10 kHz SCS plus CMM (10 kHz SCS+CMM) in 216 patients with refractory PDN. After 6 months, participants with insufficient pain relief could cross over to the other treatment. In total, 142 patients with a 10 kHz SCS system were followed for 24 months, including 84 initial 10 kHz SCS+CMM recipients and 58 crossovers from CMM alone. Assessments included pain intensity, health-related quality of life (HRQoL), sleep, and neurological function. Investigators assessed neurological function via sensory, reflex, and motor tests. They identified a clinically meaningful improvement relative to the baseline assessment if there was a significant persistent improvement in neurological function that impacted the participant's well-being and was attributable to a neurological finding. RESULTS: At 24 months, 10 kHz SCS reduced pain by a mean of 79.9% compared to baseline, with 90.1% of participants experiencing ≥50% pain relief. Participants had significantly improved HRQoL and sleep, and 65.7% demonstrated clinically meaningful neurological improvement. Five (3.2%) SCS systems were explanted due to infection. CONCLUSIONS: Over 24 months, 10 kHz SCS provided durable pain relief and significant improvements in HRQoL and sleep. Furthermore, the majority of participants demonstrated neurological improvement. These long-term data support 10 kHz SCS as a safe and highly effective therapy for PDN. TRIAL REGISTRATION: ClincalTrials.gov Identifier, NCT03228420.

A post-market, randomized, controlled, prospective study evaluating intrathecal pain medication versus conventional medical management in the non-cancer, refractory, chronic pain population (PROSPER).

INTRODUCTION: Intrathecal therapy has been limited by non-randomized prospective studies, particularly for those suffering from non-cancer. Further, no prospective, randomized studies investigating the efficacy, safety, and utilization of intrathecal polyanalgesic consensus guidelines exist. METHODS: After IRB approval, patients were enrolled in a 1:1 fashion for intrathecal drug delivery (IDD) or conventional management (CMM), employing standard of care, excluding intrathecal drug delivery, based on the principal investigator's discretion. They were followed 3, 6, 9, and 12 months. Assessments included PROMIS 29, NPRS, and PriceMonkey. RESULTS: Seventy-nine patients were screened, 54 patients were enrolled: 26 to IDD and 28 to CMM. At 3 months, there was no measurable difference in pain improvement in either subgroups within the CMM for chronic pain-related syndromes (CPRS) or failed back and related spine disorders (FBRS). For the IDD, early and maintained benefit from the baseline was statistically achieved. Cost analysis of pump to CMM breakeven was 4.5 months. There were no adverse events related to compounded intrathecal medications. CONCLUSION: This is the first randomized prospective, multicenter study investigating the safety, cost, and efficacy of off-label medications for intrathecal therapy, as compared to conventional management, and suggests early detection of improvement, cost savings, safety of intrathecal compounded medication use, and safety and efficacy of employing the PACC guidance.

High-Frequency 10-kHz Spinal Cord Stimulation Improves Health-Related Quality of Life in Patients With Refractory Painful Diabetic Neuropathy: 12-Month Results From a Randomized Controlled Trial.

Objective: To evaluate high-frequency (10-kHz) spinal cord stimulation (SCS) treatment in refractory painful diabetic neuropathy. Patients and Methods: A prospective, multicenter randomized controlled trial was conducted between Aug 28, 2017 and March 16, 2021, comparing conventional medical management (CMM) with 10-kHz SCS+CMM. The participants had hemoglobin A1c level of less than or equal to 10% and pain greater than or equal to 5 of 10 cm on visual analog scale, with painful diabetic neuropathy symptoms 12 months or more refractory to gabapentinoids and at least 1 other analgesic class. Assessments included measures of pain, neurologic function, and health-related quality of life (HRQoL) over 12 months with optional crossover at 6 months. Results: The participants were randomized 1:1 to CMM (n=103) or 10-kHz SCS+CMM (n=113). At 6 months, 77 of 95 (81%) CMM group participants opted for crossover, whereas none of the 10-kHz SCS group participants did so. At 12 months, the mean pain relief from baseline among participants implanted with 10-kHz SCS was 74.3% (95% CI, 70.1-78.5), and 121 of 142 (85%) participants were treatment responders (≥50% pain relief). Treatment with 10-kHz SCS improved HRQoL, including a mean improvement in the EuroQol 5-dimensional questionnaire index score of 0.136 (95% CI, 0.104-0.169). The participants also reported significantly less pain interference with sleep, mood, and daily activities. At 12 months, 131 of 142 (92%) participants were "satisfied" or "very satisfied" with the 10-kHz SCS treatment. Conclusion: The 10-kHz SCS treatment resulted in substantial pain relief and improvement in overall HRQoL 2.5- to 4.5-fold higher than the minimal clinically important difference. The outcomes were durable over 12 months and support 10-kHz SCS treatment in patients with refractory painful diabetic neuropathy. Trial registration: clincaltrials.gov Identifier: NCT03228420.

Effect of High-frequency (10-kHz) Spinal Cord Stimulation in Patients With Painful Diabetic Neuropathy: A Randomized Clinical Trial.

Importance: Many patients with diabetic peripheral neuropathy experience chronic pain and inadequate relief despite best available medical treatments. Objective: To determine whether 10-kHz spinal cord stimulation (SCS) improves outcomes for patients with refractory painful diabetic neuropathy (PDN). Design, Setting, and Participants: The prospective, multicenter, open-label SENZA-PDN randomized clinical trial compared conventional medical management (CMM) with 10-kHz SCS plus CMM. Participants with PDN for 1 year or more refractory to gabapentinoids and at least 1 other analgesic class, lower limb pain intensity of 5 cm or more on a 10-cm visual analogue scale (VAS), body mass index (calculated as weight in kilograms divided by height in meters squared) of 45 or less, hemoglobin A1c (HbA1c) of 10% or less, daily morphine equivalents of 120 mg or less, and medically appropriate for the procedure were recruited from clinic patient populations and digital advertising. Participants were enrolled from multiple sites across the US, including academic centers and community pain clinics, between August 2017 and August 2019 with 6-month follow-up and optional crossover at 6 months. Screening 430 patients resulted in 214 who were excluded or declined participation and 216 who were randomized. At 6-month follow-up, 187 patients were evaluated. Interventions: Implanted medical device delivering 10-kHz SCS. Main Outcomes and Measures: The prespecified primary end point was percentage of participants with 50% pain relief or more on VAS without worsening of baseline neurological deficits at 3 months. Secondary end points were tested hierarchically, as prespecified in the analysis plan. Measures included pain VAS, neurological examination, health-related quality of life (EuroQol Five-Dimension questionnaire), and HbA1c over 6 months. Results: Of 216 randomized patients, 136 (63.0%) were male, and the mean (SD) age was 60.8 (10.7) years. Additionally, the median (interquartile range) duration of diabetes and peripheral neuropathy were 10.9 (6.3-16.4) years and 5.6 (3.0-10.1) years, respectively. The primary end point assessed in the intention-to-treat population was met by 5 of 94 patients in the CMM group (5%) and 75 of 95 patients in the 10-kHz SCS plus CMM group (79%; difference, 73.6%; 95% CI, 64.2-83.0; P < .001). Infections requiring device explant occurred in 2 patients in the 10-kHz SCS plus CMM group (2%). For the CMM group, the mean pain VAS score was 7.0 cm (95% CI, 6.7-7.3) at baseline and 6.9 cm (95% CI, 6.5-7.3) at 6 months. For the 10-kHz SCS plus CMM group, the mean pain VAS score was 7.6 cm (95% CI, 7.3-7.9) at baseline and 1.7 cm (95% CI, 1.3-2.1) at 6 months. Investigators observed neurological examination improvements for 3 of 92 patients in the CMM group (3%) and 52 of 84 in the 10-kHz SCS plus CMM group (62%) at 6 months (difference, 58.6%; 95% CI, 47.6-69.6; P < .001). Conclusions and Relevance: Substantial pain relief and improved health-related quality of life sustained over 6 months demonstrates 10-kHz SCS can safely and effectively treat patients with refractory PDN. Trial Registration: ClincalTrials.gov Identifier: NCT03228420.

10 kHz High-Frequency Spinal Cord Stimulation for Chronic Thoracic Pain: A Multicenter Case Series and a Guide for Optimal Anatomic Lead Placement.

BACKGROUND: Surgical options for thoracic pain are limited and carry significant risk and morbidity. Spinal cord stimulation has the potential to be used for treatment of thoracic pain, as it has been useful for treating multiple types of chronic pain. Conventional tonic stimulation is limited in the treatment of thoracic pain, as it can produce paresthesia that is difficult to localize. Conversely, high-frequency spinal cord stimulation (HF-SCS) does not activate dorsal column A Beta fibers and does not produce paresthesia, and thus may be more beneficial in treating thoracic back pain not manageable with tonic stimulation. OBJECTIVES: To evaluate (1) the efficacy of 10 kHz HF-SCS for patients with chronic thoracic pain; and (2) appropriate paresthesia-free lead placement and programming targets for 10 kHz HF-SCS for patients with chronic thoracic pain. STUDY DESIGN: Retrospective case series. SETTING: Multisite academic medical center or pain clinic. METHODS: A retrospective chart review was performed on 19 patients with thoracic back pain who underwent HF-SCS implantation. These patients had lead placement and stimulation between the T1-T6 vertebral levels. Outcome measures collected include location of device implant, stimulation settings, and pain scores at baseline, end of trial, and 1, 6, and 12 months postimplant. Follow-up phone calls collected information on if the patient reported functional improvement, improved sleep, or decreased pain medication usage. A Wilcoxon signed-rank test compared differences in mean pain scores across time points. RESULTS: Significantly decreased Visual Analog Scale scores were observed with 17/19 (89.5%) patients demonstrating response to therapy (> 50% reduction in pain scores). These results were sustained relative to baseline at 1, 6, and 12 months postimplant, depending on length of follow-up. Many patients also reported functional improvement (17/19), improved sleep (14/19), and reduction in use of pain medications after implantation (9/19). A total of 15/19 patients reported best relief when contacts over T1 or T2 vertebrae were used for stimulation. LIMITATIONS: This study is limited by its retrospective design. Additionally, including documentation from multiple sites may be prone to selection and abstraction bias. Data were also not available for all patients at all time points. CONCLUSIONS: HF-SCS may be a viable option for significant, long-lasting pain relief for thoracic back pain. There may also be evidence for anatomically based lead placement and programming for thoracic back pain. Randomized, controlled trials with extended follow-up are needed to further evaluate this therapy. KEY WORDS: Thoracic pain, back pain, spinal cord stimulation, high frequency, 10 kHz.

Patient perception of pain care in the United States: a 5-year comparative analysis of hospital consumer assessment of health care providers and systems.

BACKGROUND: The necessity of aggressive pain management in the hospital setting is becoming increasingly evident. It has been shown to improve patient outcomes, and is now an avenue for Medicare to assess reimbursement. In this cohort analysis, we compared the March 2008 to the December 2012 Hospital Consumer Assessment of Health Plans Survey (HCAHPS) reports in order to determine if pain management has improved in the United States after this national standardized survey was created. OBJECTIVE: To evaluate whether pain perception would improve in the 2012 report relative to the 2008 report. STUDY DESIGN: Statistical analyses were conducted with the HCAHPS report to compare pain control in regards to hospital type, hospital ownership, and individual hospitals. Using the question, "How often is your pain controlled?," T-tests were used to compare each hospital type. Hospital ownerships were assessed via analysis of variance (ANOVA) testing. T-tests were conducted to track the difference of hospital performance between the 2008 and the 2012 report. Paired management data were obtained from hospitals that participated in both reports and were assessed using paired T-tests. SETTING: This survey was administered to a random sample of adult inpatients between 48 hours and 6 weeks after discharge from any hospital reporting to Centers for Medicare and Medicaid (CMS) across the US. LIMITATIONS: Limitations of this study include response bias, recall bias, and there may be bias related to types of people likely to respond to a survey, but this is inherent to data that is collected on a voluntary response. Additionally, a 3% increase in the number of patients rating their pain as always well-controlled, while statistically significant, admittedly may not be clinically significant. In addition, the raw data collected is adjusted for the effects of patient-mix. The statistical analyses performed to derive the final quarterly HCAHPS reports are unavailable to us and therefore we cannot comment on how individual factors such as age, sex, race, and education or the interaction of the aforementioned affect responses about the patient's perception on how well their pain was controlled between 2008 and 2012. RESULTS: Two thousand three hundred and ninety five hospitals reported pain management data in both 2008 and 2012. In 2012, hospitals improved their ability to "always control a patients pain" by 3.07% (P < 0.0001) in comparison to the baseline March 2008 report, which was statistically significant. According to the 2012 data, the discrepancy in pain management between acute care hospitals and critical access hospitals was 3.33% which was statistically significant (P < 0.05). Government hospitals were shown to manage pain better at baseline, but all 3 types of ownership improved their pain scores between the 2 reports which was shown to be statistically significant (P < 0.01). DISCUSSION: The HCAHPS survey is a national public standardized report used as a way to compare care in the United States. Patient pain perception has improved between the 2008 and 2012 reports. Further studies are needed to evaluate critical care hospitals.

Leucine supplementation of drinking water does not alter susceptibility to diet-induced obesity in mice.

Branched-chain amino acids (BCAA), Leu, and the signaling pathways they regulate have been reported to either improve or worsen adiposity and insulin sensitivity. Therefore, it is unclear whether dietary supplementation of Leu would be beneficial. To help address this question, we examined the effect of adding Leu (150 mmol/L; Expt. 1 and Expt. 2) or BCAA (109 mmol/L of each; Expt. 3) to the drinking water on diet-induced obesity (induced with a 60-kJ% fat diet) in singly housed C57BL6/J male mice for at least 14 wk. Liquid and solid food intakes were evaluated weekly along with body weight. During the last few weeks, several blood samples were taken at different times for plasma glucose, total cholesterol, or Leu measurements. Metabolic rate by indirect calorimetry, locomotor activity by light beam breaking, body composition by H1-NMR, and insulin tolerance were also determined. Compared with control, supplementation did not affect body weight, food intake, oxygen consumption, locomotor activity, body composition, insulin tolerance, or total cholesterol. In fed mice, this method of Leu supplementation only increased plasma Leu by 76% when the supplemented group was compared with control. On the other hand, after overnight food deprivation, the plasma Leu did not differ between these 2 groups, even though the mice in the supplemented group had continuous access to Leu-containing water during the solid food deprivation. Taken together, the results do not provide evidence that either Leu or BCAA supplementation of drinking water ameliorates diet-induced obesity in mice, although it may improve glycemia.