Five-Year Longitudinal Follow-up of Restorative Neurostimulation Shows Durability of Effectiveness in Patients With Refractory Chronic Low Back Pain Associated With Multifidus Muscle Dysfunction.

BACKGROUND: Adults with refractory, mechanical chronic low back pain associated with impaired neuromuscular control of the lumbar multifidus muscle have few treatment options that provide long-term clinical benefit. This study hypothesized that restorative neurostimulation, a rehabilitative treatment that activates the lumbar multifidus muscles to overcome underlying dysfunction, is safe and provides relevant and durable clinical benefit to patients with this specific etiology. MATERIALS AND METHODS: In this prospective five-year longitudinal follow-up of the ReActiv8-B pivotal trial, participants (N = 204) had activity-limiting, moderate-to-severe, refractory, mechanical chronic low back pain, a positive prone instability test result indicating impaired multifidus muscle control, and no indications for spine surgery. Low back pain intensity (10-cm visual analog scale [VAS]), disability (Oswestry Disability Index), and quality of life (EuroQol's "EQ-5D-5L" index) were compared with baseline and following the intent-to-treat principle, with a supporting mixed-effects model for repeated measures that accounted for missing data. RESULTS: At five years (n = 126), low back pain VAS had improved from 7.3 to 2.4 cm (-4.9; 95% CI, -5.3 to -4.5 cm; p < 0.0001), and 71.8% of participants had a reduction of ≥50%. The Oswestry Disability Index improved from 39.1 to 16.5 (-22.7; 95% CI, -25.4 to -20.8; p < 0.0001), and 61.1% of participants had reduction of ≥20 points. The EQ-5D-5L index improved from 0.585 to 0.807 (0.231; 95% CI, 0.195-0.267; p < 0.0001). Although the mixed-effects model attenuated completed-case results, conclusions and statistical significance were maintained. Of 52 subjects who were on opioids at baseline and had a five-year visit, 46% discontinued, and 23% decreased intake. The safety profile compared favorably with neurostimulator treatments for other types of back pain. No lead migrations were observed. CONCLUSION: Over a five-year period, restorative neurostimulation provided clinically substantial and durable benefits with a favorable safety profile in patients with refractory chronic low back pain associated with multifidus muscle dysfunction. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is NCT02577354; registration date: October 15, 2016; principal investigator: Christopher Gilligan, MD, Brigham and Women's Hospital, Boston, MA, USA. The study was conducted in Australia (Broadmeadow, New South Wales; Noosa Heads, Queensland; Welland, South Australia; Clayton, Victoria), Belgium (Sint-Niklaas; Wilrijk), The Netherlands (Rotterdam), UK (Leeds, London, Middlesbrough), and USA (La Jolla, CA; Santa Monica, CA; Aurora, CO; Carmel, IN; Indianapolis, IN; Kansas City, KS; Boston, MA; Royal Oak, MI; Durham, NC; Winston-Salem, NC; Cleveland, OH; Providence, RI; Spartanburg, SC; Spokane, WA; Charleston, WV).

Treating Chronic, Intractable Pain with a Miniaturized Spinal Cord Stimulation System: 1-Year Outcomes from the AUS-nPower Study During the COVID-19 Pandemic.

Purpose: Spinal cord stimulation (SCS) is a highly effective treatment for chronic neuropathic pain. Despite recent advances in technology, treatment gaps remain. A small SCS system with a miniaturized implantable pulse generator (micro-IPG; <1.5 cm3 in volume) and an externally worn power source may be preferred by patients who do not want a large, implanted battery. We report here the long-term outcomes from the first-in-human study evaluating the safety and performance of a new neurostimulation system. Patients and Methods: This was a prospective, multi-center, open-label, single-arm study to evaluate this SCS system, in the treatment of chronic, intractable leg and low-back pain. Consented subjects who passed screening continued on to the long-term phase of the study. One-year, patient-reported outcomes (PRO's) such as pain (Numeric Rating Scale, NRS), functional disability, quality of life, and mood were captured. Results: Twenty-six (26) evaluable subjects with permanent implants were included in this analysis. The average leg pain NRS score decreased from 6.8 ± 1.2 at baseline to 1.1 ± 1.2 at the end of the study (p < 0.001), while the average low-back pain NRS score decreased from 6.8 ± 1.2 to 1.5 ± 1.2 (p < 0.001). The responder rate (proportion with ≥50% pain relief) was 91% in the leg(s) and 82% in the low back. There were significant improvements in functional disability (Oswestry Disability Index) and in mood (Beck Depression Inventory), demonstrating a 46% and 62% improvement, respectively (p < 0.001). Eleven-point Likert scales demonstrated the wearable to be very comfortable and very easy to use. Conclusion: There were considerable challenges conducting a clinical study during the COVID-19 pandemic, such as missed study programming visits. Nevertheless, subjects had significant PRO improvements through 1-year. The small size of the implanted device, along with a proprietary waveform, may allow for improved SCS outcomes and a drop in incidence of IPG-pocket pain.

Early Experience With a Novel Miniaturized Spinal Cord Stimulation System for the Management of Chronic Intractable Pain of the Back and Legs.

INTRODUCTION: A novel, spinal cord stimulation (SCS) system with a battery-free miniaturized implantable pulse generator (IPG) was used in this feasibility study. The system uses an external power source that communicates bidirectionally with the IPG (< 1.5 cm3). Human factors, subject comfort, and effects on low back and leg pain were evaluated in this first-in-human study. MATERIALS AND METHODS: A prospective, multicenter, open-label clinical trial was initiated to evaluate the safety and performance of a novel miniaturized stimulator in the treatment of chronic, intractable leg and low-back pain. Eligible subjects were recruited for the study and gave consent. Subjects who passed the screening/trial phase (defined as ≥ 50% decrease in pain) continued to the long-term implant phase and were followed up at predefined time points after device activation. Interim clinical and usability outcomes were captured and reported at 90 days. RESULTS: Results of 22 subjects who chose a novel pulsed stimulation pattern therapy using the battery-free IPG (< 1.5 cm3) are described here. At 90-days follow-up, the average pain reduction was 79% in the leg (n = 22; p < 0.0001) and 76% in the low back (n = 21; p < 0.0001) compared with baseline. Responder rates (≥ 50% pain relief) at 90 days were 86% in leg pain (19/22) and 81% in low-back pain (17/21). Subjects rated the level of comfort of the external wearable power source to be 0.41 ± 0.73 at 90 days on an 11-point rating scale (0 = very comfortable, 10 = very uncomfortable). DISCUSSION: These interim results from the ongoing study indicate the favorable efficacy and usability of a novel, externally powered, battery-free SCS IPG (< 1.5 cm3) for leg and low-back pain. Study subjects wore the external power source continuously and found it comfortable, and the system provided significant pain relief. These preliminary findings warrant further investigation. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is ACTRN12618001862235.

A Novel Pulsed Stimulation Pattern in Spinal Cord Stimulation: Clinical Results and Postulated Mechanisms of Action in the Treatment of Chronic Low Back and Leg Pain.

OBJECTIVES: The aim of this article is to discuss the possible mechanisms of action (MOAs) and results of a pilot study of a novel, anatomically placed, and paresthesia-independent, neurostimulation waveform for the management of chronic intractable pain. MATERIALS AND METHODS: A novel, multilayered pulsed stimulation pattern (PSP) that comprises three temporal layers, a Pulse Pattern layer, Train layer, and Dosage layer, was developed for the treatment of chronic intractable pain. During preliminary development, the utility was evaluated of anatomical PSP (aPSP) in human subjects with chronic intractable pain of the leg(s) and/or low back, compared with that of traditional spinal cord stimulation (T-SCS) and physiological PSP. The scientific theory and testing presented in this article provide the preliminary justification for the potential MOAs by which PSP may operate. RESULTS: During the pilot study, aPSP (n = 31) yielded a greater decrease in both back and leg pain than did T-SCS (back: -60% vs -46%; legs: -63% vs -43%). In addition, aPSP yielded higher responder rates for both back and leg pain than did T-SCS (61% vs 48% and 78% vs 50%, respectively). DISCUSSION: The novel, multilayered approach of PSP may provide multimechanistic therapeutic relief through preferential fiber activation in the dorsal column, optimization of the neural onset response, and use of both the medial and lateral pathway through the thalamic nuclei. The results of the pilot study presented here suggest a robust responder rate, with several subjects (five subjects with back pain and three subjects with leg pain) achieving complete relief from PSP during the acute follow-up period. These clinical findings suggest PSP may provide a multimechanistic, anatomical, and clinically effective management for intractable chronic pain. Because of the limited sample size of clinical data, further testing and long-term clinical assessments are warranted to confirm these preliminary findings.

Long-Term Outcomes of Restorative Neurostimulation in Patients With Refractory Chronic Low Back Pain Secondary to Multifidus Dysfunction: Two-Year Results of the ReActiv8-B Pivotal Trial.

BACKGROUND: Impaired neuromuscular control and degeneration of the multifidus muscle have been linked to the development of refractory chronic low back pain (CLBP). An implantable restorative-neurostimulator system can override the underlying multifidus inhibition by eliciting episodic, isolated contractions. The ReActiv8-B randomized, active-sham-controlled trial provided effectiveness and safety evidence for this system, and all participants received therapeutic stimulation from four months onward. OBJECTIVE: This study aimed to evaluate the two-year effectiveness of this restorative neurostimulator in patients with disabling CLBP secondary to multifidus muscle dysfunction and no indications for spine surgery. MATERIALS AND METHODS: Open-label follow-up of 204 participants implanted with a restorative neurostimulation system (ReActiv8, Mainstay Medical, Dublin, Ireland) was performed. Pain intensity (visual analog scale [VAS]), disability (Oswestry disability index [ODI]), quality-of-life (EQ-5D-5L), and opioid intake were assessed at baseline, six months, one year, and two years after activation. RESULTS: At two years (n = 156), the proportion of participants with ≥50% CLBP relief was 71%, and 65% reported CLBP resolution (VAS ≤ 2.5 cm); 61% had a reduction in ODI of ≥20 points, 76% had improvements of ≥50% in VAS and/or ≥20 points in ODI, and 56% had these substantial improvements in both VAS and ODI. A total of 87% of participants had continued device use during the second year for a median of 43% of the maximum duration, and 60% (34 of 57) had voluntarily discontinued (39%) or reduced (21%) opioid intake. CONCLUSIONS: At two years, 76% of participants experienced substantial, clinically meaningful improvements in pain, disability, or both. These results provide evidence of long-term effectiveness and durability of restorative neurostimulation in patients with disabling CLBP, secondary to multifidus muscle dysfunction. CLINICAL TRIAL REGISTRATION: The study is registered on clinicaltrials.gov with identifier NCT02577354.

Three-Year Durability of Restorative Neurostimulation Effectiveness in Patients With Chronic Low Back Pain and Multifidus Muscle Dysfunction.

BACKGROUND: Restorative neurostimulation is a rehabilitative treatment for patients with refractory chronic low back pain (CLBP) associated with dysfunction of the lumbar multifidus muscle resulting in impaired neuromuscular control. The ReActiv8-B randomized, sham-controlled trial provided evidence of the effectiveness and safety of an implanted, restorative neurostimulator. The two-year analysis previously published in this journal demonstrated accrual of clinical benefits and long-term durability. OBJECTIVE: Evaluation of three-year effectiveness and safety in patients with refractory, disabling CLBP secondary to multifidus muscle dysfunction and no indications for spine surgery. MATERIALS AND METHODS: Prospective, observational follow-up of the 204 implanted trial participants. Low back pain visual analog scale (VAS), Oswestry Disability Index (ODI), EuroQol quality of life survey, and opioid intake were assessed at baseline, six months, and one, two, and three years after activation. The mixed-effects model repeated measures approach was used to provide implicit imputations of missing data for continuous outcomes and multiple imputation for proportion estimates. RESULTS: Data were collected from 133 participants, and 16 patients missed their three-year follow-up because of coronavirus disease restrictions but remain available for future follow-up. A total of 62% of participants had a ≥ 70% VAS reduction, and 67% reported CLBP resolution (VAS ≤ 2.5cm); 63% had a reduction in ODI of ≥ 20 points; 83% had improvements of ≥ 50% in VAS and/or ≥ 20 points in ODI, and 56% had these substantial improvements in both VAS and ODI. A total of 71% (36/51) participants on opioids at baseline had voluntarily discontinued (49%) or reduced (22%) opioid intake. The attenuation of effectiveness in the imputed (N = 204) analyses was relatively small and did not affect the statistical significance and clinical relevance of these results. The safety profile remains favorable, and no lead migrations have been observed to date. CONCLUSION: At three years, 83% of participants experienced clinically substantial improvements in pain, disability, or both. The results confirm the long-term effectiveness, durability, and safety of restorative neurostimulation in patients with disabling CLBP associated with multifidus muscle dysfunction. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is NCT02577354.

Historic redlining in Columbus, Ohio associated with stroke prevalence.

BACKGROUND: Racial disparities exist in stroke and stroke outcomes. In an ecologic study, using the Home Owners' Loan Corporation (HOLC) "redlining" scores, as indicator of historic racialized lending practices, we hypothesized that census tracts with high historic redlining are associated with higher stroke prevalence. METHODS: Weighted historic redlining scores (HRS) were calculated using the proportion of 1930s HOLC residential security grades contained within 2010 census tract boundaries of Columbus, Ohio. Stroke prevalence (adults >=18) was obtained at the census tract-level from the CDC's 500 Cities Project. Sociodemographic census tract level data (American Community Survey 2014-2018) were considered mediators in the causal association between historic redlining and stroke prevalence and were not controlled for in regression analysis. HRS and stroke prevalence associations were evaluated with and without adjustment for proportion of census tract 65 years and older. RESULTS: Census tracts in the highest quartile of HRS (greater redlining) had 1.73% higher stroke prevalence compared to those in the lowest quartile (95% CI:0.41,3.05) adjusting for proportion 65 years and older. No other interquartile differences were observed. CONCLUSIONS: Historic redlining practices are a form of structural racism that established geographic systems of disadvantage and consequently, poor health outcomes. Our findings demonstrate disparate stroke prevalence by degree of historic redlining in census tracts across Columbus, Ohio.

Low-dose mesenchymal stem cell therapy for discogenic pain: safety and efficacy results from a 1-year feasibility study.

Aim: To evaluate safety and efficacy of low dose autologous adipose-derived mesenchymal stem cells (ADMSCs) for treatment of disc degeneration resulting in low back pain (LBP). Methods: Nine participants with chronic LBP originating from single-level lumbar disc disease underwent intradiscal injection of 10 million ADMSCs with optional repetition after 6 months. Results: No unexpected or serious adverse events were recorded. Seven (78%) of participants reported reductions in pain 12 months after treatment. Five (56%) reported increased work capacity. Three (33%) reduced analgesic medication. Improvements in EQ-5D and Oswestry disability index results were observed. MRI demonstrated no further disc degeneration and improvements to annular fissures and disc protrusions. Conclusion: This study provides initial evidence of safety and efficacy of ADMSCs for discogenic LBP.

An implantable restorative-neurostimulator for refractory mechanical chronic low back pain: a randomized sham-controlled clinical trial.

ABSTRACT: Chronic low back pain can be caused by impaired control and degeneration of the multifidus muscles and consequent functional instability of the lumbar spine. Available treatment options have limited effectiveness and prognosis is unfavorable. We conducted an international randomized, double-blind, sham-controlled trial at 26 multidisciplinary centers to determine safety and efficacy of an implantable, restorative neurostimulator designed to restore multifidus neuromuscular control and facilitate relief of symptoms (clinicaltrials.gov identifier: NCT02577354). Two hundred four eligible participants with refractory mechanical (musculoskeletal) chronic LBP and a positive prone instability test indicating impaired multifidus control were implanted and randomized to therapeutic (N = 102) or low-level sham (N = 102) stimulation of the medial branch of the dorsal ramus nerve (multifidus nerve supply) for 30 minutes twice daily. The primary endpoint was the comparison of responder proportions (≥30% relief on the LBP visual analogue scale without analgesics increase) at 120 days. After the primary endpoint assessment, participants in the sham-control group switched to therapeutic stimulation and the combined cohort was assessed through 1 year for long-term outcomes and adverse events. The primary endpoint was inconclusive in terms of treatment superiority (57.1% vs 46.6%; difference: 10.4%; 95% confidence interval, -3.3% to 24.1%, P = 0.138). Prespecified secondary outcomes and analyses were consistent with a modest but clinically meaningful treatment benefit at 120 days. Improvements from baseline, which continued to accrue in all outcome measures after conclusion of the double-blind phase, were clinically important at 1 year. The incidence of serious procedure- or device-related adverse events (3.9%) compared favorably with other neuromodulation therapies for chronic pain.

Durability of the Therapeutic Effect of Restorative Neurostimulation for Refractory Chronic Low Back Pain.

OBJECTIVES: The purpose of the ongoing follow-up of ReActiv8-A clinical trial is to document the longitudinal benefits of episodic stimulation of the dorsal ramus medial branch and consequent contraction of the lumbar multifidus in patients with refractory mechanical chronic low back pain (CLBP). We report the four-year outcomes of this trial. MATERIALS AND METHODS: ReActiv8-A is a prospective, single-arm trial performed at nine sites in the United Kingdom, Belgium, and Australia. Eligible patients had disabling CLBP (low back pain Numeric Rating Scale [NRS] ≥6; Oswestry Disability Index [ODI] ≥25), no indications for spine surgery or spinal cord stimulation, and failed conventional management including at least physical therapy and medications for low back pain. Fourteen days postimplantation, stimulation parameters were programmed to elicit strong, smooth contractions of the multifidus, and participants were given instructions to activate the device for 30-min stimulation-sessions twice daily. Annual follow-up through four years included collection of NRS, ODI, and European Quality of Life Score on Five Dimensions (EQ-5D). Background on mechanisms, trial design, and one-year outcomes were previously described. RESULTS: At baseline (N = 53) (mean ± SD) age was 44 ± 10 years; duration of back pain was 14 ± 11 years, NRS was 6.8 ± 0.8, ODI 44.9 ± 10.1, and EQ-5D 0.434 ± 0.185. Mean improvements from baseline were statistically significant (p < 0.001) and clinically meaningful for all follow-ups. Patients completing year 4 follow-up, reported mean (±standard error of the mean) NRS: 3.2 ± 0.4, ODI: 23.0 ± 3.2, and EQ-5D: 0.721 ± 0.035. Moreover, 73% of participants had a clinically meaningful improvement of ≥2 points on NRS, 76% of ≥10 points on ODI, and 62.5% had a clinically meaningful improvement in both NRS and ODI and 97% were (very) satisfied with treatment. CONCLUSIONS: In participants with disabling intractable CLBP who receive long-term restorative neurostimulation, treatment satisfaction remains high and improvements in pain, disability, and quality-of-life are clinically meaningful and durable through four years.

The legacy of structural racism: Associations between historic redlining, current mortgage lending, and health.

Structural racism, which is embedded in past and present operations of the U.S. housing market, is a fundamental cause of racial health inequities. We conducted an ecologic study to 1) examine historic redlining in relation to current neighborhood lending discrimination and three key indicators of societal health (mental health, physical health, and infant mortality rate (IMR)) and 2) investigate sustained lending disinvestment as a determinant of current neighborhood health in one of the most hypersegregated metropolitan areas in the United States, Milwaukee, Wisconsin. We calculated weighted historic redlining scores from the proportion of 1930s Home Owners' Loan Corporation residential security grades contained within 2010 census tract boundaries. We combined two lending indicators from 2018 Home Mortgage Disclosure Act data to capture current neighborhood lending discrimination: low lending occurrence and high cost loans (measured via loan rate spread). Using historic redlining score and current lending discrimination, we created a 4-level hierarchical measure of lending trajectory. In Milwaukee neighborhoods, greater historic redlining was associated with current lending discrimination (OR = 1.73, 95%CI: 1.16, 2.58) and increased prevalence of poor physical health (ß = 1.34, 95%CI: 0.40, 2.28) and poor mental health (ß = 1.26, 95%CI: 0.51, 2.01). Historic redlining was not associated with neighborhood IMR (ß = -0.48, 95%CI: -2.12, 1.15). A graded association was observed between lending trajectory and health: neighborhoods with high sustained disinvestment had worse physical and mental health than neighborhoods with high investment (poor physical health: ß = 5.33, 95%CI: 3.05, 7.61; poor mental health: ß = 4.32, 95%CI: 2.44, 6.20). IMR was highest in 'disinvested' neighborhoods (ß = 5.87, 95%CI: 0.52, 11.22). Our findings illustrate ongoing legacies of government sponsored historic redlining. Structural racism, as manifested in historic and current forms of lending disinvestment, predicts poor health in Milwaukee's hypersegregated neighborhoods. We endorse equity focused policies that dismantle and repair the ways racism is entrenched in America's social fabric.

Social Inequities in Urban Heat and Greenspace: Analyzing Climate Justice in Delhi, India.

Climate change and rapid urbanization currently pose major challenges for equitable development in megacities of the Global South, such as Delhi, India. This study considers how urban social inequities are distributed in terms of burdens and benefits by quantifying exposure through an urban heat risk index (UHRI), and proximity to greenspace through the normalized difference vegetation index (NDVI), at the ward level in Delhi. Landsat derived remote sensing imagery for May and September 2011 is used in a sensitivity analysis of varying seasonal exposure. Multivariable models based on generalized estimating equations (GEEs) reveal significant statistical associations (p < 0.05) between UHRI/NDVI and several indicators of social vulnerability. For example, the proportions of children (ß = 0.922, p = 0.024) and agricultural workers (ß = 0.394, p = 0.016) are positively associated with the May UHRI, while the proportions of households with assets (ß = -1.978, p = 0.017) and households with electricity (ß = -0.605, p = 0.010) are negatively associated with the May UHRI. In contrast, the proportions of children (ß = 0.001, p = 0.633) and agricultural workers (ß = 0.002, p = 0.356) are not significantly associated with the May NDVI, while the proportions of households with assets (ß = 0.013, p = 0.010) and those with electricity (ß = 0.008, p = 0.006) are positively associated with the May NDVI. Our findings emphasize the need for future research and policies to consider how socially vulnerable groups are inequitably exposed to the impact of climate change-related urban heat without the mitigating effects of greenspace.

Dorsal Root Ganglion Stimulation Is Paresthesia-Independent: A Retrospective Study.

INTRODUCTION: Neuromodulation is an important tool for achieving pain relief in otherwise-intractable neuropathic pain conditions. Dorsal root ganglion (DRG) stimulation, in which primary sensory neurons are stimulated prior to their entry into the spinal canal, provides treatment with high levels of dermatomal specificity and can provide advantages compared to conventional spinal cord stimulation. Although DRG stimulation can produce perceptible paresthesias, many patients operate their systems at subthreshold amplitudes that do not elicit this sensation. Pain relief both with and without paresthesia was investigated in this retrospective analysis. MATERIALS AND METHODS: A retrospective review of all qualifying permanent DRG stimulation systems at a single center over more than a three-year period was completed. Pain (0-10 numeric rating scale) was assessed at baseline, at the end of the trial, and after three, six, and twelve months of treatment. Patients were categorized based on their usage of the stimulator at amplitudes that either did or did not produce paresthesias. RESULTS: Of the 39 patients, 34 (87%) reported having no-paresthesias at any of the follow-up visits. Average pain relief was 73.9% after the trial period and 63.1% after 12 months of treatment. The responder rate (50% or better pain relief) after three months of treatment was more than 80%. Exploratory subgroup analyses showed that similar degrees of pain relief were achieved in numerous body regions and with various pain etiologies. The five patients who reported paresthesias during treatment had pain relief similar to those of the group that did not experience paresthesias. DISCUSSION: Clinically significant and sustained pain relief over more than a period of 12 months was achieved with DRG stimulation programmed at amplitudes below the perceptual level. Thus, the reported analgesia was paresthesia-independent. That good clinical outcomes were observed independent of the generation of paresthesia in DRG stimulation suggests several mechanisms of action, including the inhibition of supraspinal regions involved in somatic paresthesia sensation. The retrospective results presented here posit that future prospective study of DRG stimulation delivered at below the threshold of perceptible paresthesias is warranted.

Incorporating Continuity in a 7-On 7-Off Hospitalist Model and the Correlation With Patient Handoffs and Length of Stay.

Little research in hospital medicine examines the effects of hospitalist continuity on patient outcomes. This study implemented a novel staffing model with approximately half of rounding teams starting their 7-day workweek on Monday and the others on Friday. Teams admitted their own patients on their first 4 days with additional nighttime admissions handed off to those teams. No admissions were given to teams on their last 3 days. Length of stay was significantly reduced from 6.34 days in 2015 to 5.7 days in 2016 (P < .002) with a significant decrease in handoffs. There was an increase in odds ratio of death (1.37, SE = .128) with each additional hospitalist involved in a patient's care while adjusting for year and number of patient diagnoses (P < .001). There was no statistical difference in charges, 30-day readmissions, or mortality between years.

Sickle Cell Trait and Sudden Death.

Sickle cell trait has long been considered a benign condition but continues to be the leading cause of death in young African Americans in military basic training and civilian organized sports. There continues to be a great deal of controversy surrounding sickle cell trait and its association with exercise-related morbidity and sudden death. Even though sickle cell trait has a high prevalence among African Americans, many clinicians believe the potential adverse consequences should have been mitigated by actions such as universal screening in the USA at birth for sickle hemoglobin, National Collegiate Athletic Association (NCAA) rule changes, and changes in the US Military boot camp system. Sudden death due to periods of extreme physical exertion continues to occur in individuals with sickle cell trait.

New Therapy for Refractory Chronic Mechanical Low Back Pain-Restorative Neurostimulation to Activate the Lumbar Multifidus: One Year Results of a Prospective Multicenter Clinical Trial.

OBJECTIVES: The purpose of the international multicenter prospective single arm clinical trial was to evaluate restorative neurostimulation eliciting episodic contraction of the lumbar multifidus for treatment of chronic mechanical low back pain (CMLBP) in patients who have failed conventional therapy and are not candidates for surgery or spinal cord stimulation (SCS). MATERIALS AND METHODS: Fifty-three subjects were implanted with a neurostimulator (ReActiv8, Mainstay Medical Limited, Dublin, Ireland). Leads were positioned bilaterally with electrodes close to the medial branch of the L2 dorsal ramus nerve. The primary outcome measure was low back pain evaluated on a 10-Point Numerical Rating Scale (NRS). Responders were defined as subjects with an improvement of at least the Minimal Clinically Important Difference (MCID) of ≥2-point in low back pain NRS without a clinically meaningful increase in LBP medications at 90 days. Secondary outcome measures included Oswestry Disability Index (ODI) and Quality of Life (QoL; EQ-5D). RESULTS: For 53 subjects with an average duration of CLBP of 14 years and average NRS of 7 and for whom no other therapies had provided satisfactory pain relief, the responder rate was 58%. The percentage of subjects at 90 days, six months, and one year with ≥MCID improvement in single day NRS was 63%, 61%, and 57%, respectively. Percentage of subjects with ≥MCID improvement in ODI was 52%, 57%, and 60% while those with ≥MCID improvement in EQ-5D was 88%, 82%, and 81%. There were no unanticipated adverse events (AEs) or serious AEs related to the device, procedure, or therapy. The initial surgical approach led to a risk of lead fracture, which was mitigated by a modification to the surgical approach. CONCLUSIONS: Electrical stimulation to elicit episodic lumbar multifidus contraction is a new treatment option for CMLBP. Results demonstrate clinically important, statistically significant, and lasting improvement in pain, disability, and QoL.

Peripheral Nerve Field Stimulation Therapy for Patients With Thoracic Pain: A Prospective Study.

OBJECTIVE: Relative to the number of patients suffering chronic lumbar and cervical pain, fewer patients suffer persistent thoracic pain. Consequently there is less literature, with smaller sample sizes, reporting treatment of this cohort. Here, we assess peripheral nerve field stimulation (PNfS) as a potential treatment for chronic thoracic pain. MATERIALS AND METHODS: This study included 20 consecutive chronic thoracic pain sufferers that responded successfully to PNfS trial. The patients were subsequently implanted with permanent eight-contact electrode linear percutaneous leads within their major area of pain. Patients were followed up at 12 months for outcome reporting. All 20 patients were considered in the statistical analysis, despite removal of three devices prior to follow up. RESULTS: The average baseline pre-treatment Numerical Pain Rating Scale (NPRS) score was 7.75 ± 1.4. Following PNfS, the mean NPRS score was 2.25 ±2.14, reflecting a significant average improvement of 5.5 ± 3.31. Three patients were explanted prior to follow up: the first gained excellent thoracic pain relief but pain at the Implantable Pulse Generator (IPG) site could not be overcome, the second achieved excellent pain relief but the PNfS was removed due to recurrent infection and in the final instance, the intervention offered only poor relief and the device removed. CONCLUSION: PNfS is an effective intervention for intractable disabling thoracic pain, offering sustained and worthwhile pain relief, for the overwhelming majority of the cohort. This may be especially true when considering a combined treatment approach of PNfS and analgesic use to manage remnant pain.

High Frequency Spinal Cord Stimulation at 10 kHz for the Treatment of Chronic Pain: 6-Month Australian Clinical Experience.

BACKGROUND: High frequency spinal cord stimulation at 10 kHz (HF10 therapy) represents a prominent advance in spinal cord stimulation (SCS) therapy, having demonstrated enhanced efficacy in patients with back and leg pain and pain relief without paresthesia that is sustained at 24 months post implant. OBJECTIVE: To report on the effectiveness HF10 SCS therapy for a wide range of intractable pain conditions in clinical practice. STUDY DESIGN: Retrospective investigation of 256 patients who trialed HF10 SCS for chronic intractable pain of various etiologies. SETTING: Three Australian pain clinics. METHODS: Two hundred fifty-six patients trialed HF10 SCS with view of a permanent implant if successful. Pain distributions included back + leg, back only, head ± neck, and neck ± arm/shoulder. About 30% of patients had previously failed traditional low-frequency paresthesia-based stimulation, while the remaining cohort were either highly refractory to treatment or not recommended by the pain physician for traditional SCS. Pain scores (numerical pain rating scale - NPRS) and functional outcome measures (Oswestry Disability Index - ODI; and activity tolerance times) were assessed at baseline, post-trial, and at 3 and 6 months post-implant as available in the medical records. RESULTS: Of the 256 patients, 189 (73%) reported a positive trial and were implanted. Patients with back + leg pain demonstrated the highest trial success rate (81%). A mean reduction in pain, among those for whom data were available, of 50% was sustained up to 6 months post-implant across the entire patient population. Sixty-eight percent of patients who failed traditional SCS reported a positive trial and mean pain relief at 6 months was 49% (P < 0.001). An 8.6 point reduction in ODI (21%) at 6 months and improved sitting, standing, and walking tolerances were also reported. LIMITATIONS: As data was collected retrospectively, missing data points were unavoidable; this was primarily due to inconsistent data collection and patients being lost to follow-up. Patient populations were diverse and a control group was not appropriate in this setting. CONCLUSIONS: These retrospective results demonstrate a significant advancement for patients suffering with chronic intractable pain and are consistent with recently published clinical results for HF10 SCS. HF10 SCS appears to be a viable, paresthesia-free alternative to traditional SCS, with high trial success rates, demonstrated effectiveness in a range of pain distributions including those typically difficult to treat with traditional SCS, and the possibility to restore pain control in patients who have previously failed traditional SCS. KEY WORDS: Spinal cord stimulation, high frequency stimulation, HF10, paresthesia-free stimulation, back pain, leg pain, cervical pain, neuromodulation.

Improved Pain Relief With Burst Spinal Cord Stimulation for Two Weeks in Patients Using Tonic Stimulation: Results From a Small Clinical Study.

OBJECTIVES: Conventional spinal cord stimulation (SCS) delivers a tonic waveform with consistent stream of pulses; burst delivers groups of pulses separated by short pulse-free periods. The current study compared the short-term safety and efficacy of burst with tonic stimulation in subjects already receiving SCS. MATERIALS AND METHODS: At 4 IRB-approved sites, 22 subjects previously implanted with an SCS device for intractable, chronic pain gave informed consent and received burst stimulation for 14 days. Subjects reported average daily Visual Analog Scale (VAS) for overall, trunk, and limb pain using tonic stimulation and after 7 and 14 days of burst stimulation. Thoughts about pain were assessed using the Pain Catastrophizing Scale. Areas of paresthesia were assessed during tonic and burst stimulation using body maps. Assessment of patient satisfaction and preferred stimulation occurred after 14 days of burst. RESULTS: Average daily overall VAS reduced 46% from a mean of 53.5 (±20.2) mm during tonic SCS to 28.5 (±18.1) mm during burst (p < 0.001); trunk and limb VAS scores were also reduced by 33% and 51%, respectively. During burst, 16 subjects (73%) reported no paresthesia, 5 (23%) reported a reduction, and 1 (4%) reported increased paresthesia. After 14 days, 21 subjects (95%) reported being very satisfied or satisfied with burst. Burst was preferred by 20 subjects (91%), tonic by 1 (5%), and 1 (5%) reported no preference. Better pain relief was the most common reason cited for preference. CONCLUSIONS: A majority of subjects reported improved pain relief using burst compared with tonic stimulation. Most subjects experienced less paresthesia during burst and preferred burst citing better pain relief.