Disparities in Access to Spasticity Chemodenervation Specialists in the United States: A Retrospective Cross-Sectional Study.

OBJECTIVE: The aim of the study is to explore variations in access to spasticity chemodenervation specialists across several geographical, ethnic, racial, and population density factors. DESIGN: This is a retrospective cross-sectional study on Medicare Provider Utilization and Payment Data. Providers with substantial adult spasticity chemodenervation practices were included. Ratios were assessed across geographical regions as well as hospital referral regions. A multivariate linear regression model for the top 100 hospital referral regions by beneficiary population was created, using backward stepwise selection to eliminate variables with P values > 0.10 from final model. RESULTS: A total of 566 providers with spasticity chemodenervation practices were included. Unadjusted results showed lower access in nonurban versus urban areas in the form of higher patient:provider ratios (83,106 vs. 51,897). Access was also lower in areas with ≥25% Hispanic populations (141,800 vs. 58,600). Multivariate linear regression results showed similar findings with urban hospital referral regions having significantly lower ratios (-45,764 [ P = 0.004] vs. nonurban) and areas with ≥25% Hispanic populations having significantly higher ratios (+96,249 [ P = 0.003] vs. <25% Hispanic areas). CONCLUSIONS: Patients in nonurban and highly Hispanic communities face inequities in access to chemodenervation specialists. The Medicare data set analyzed only includes 12% of the US patient population; however, this elderly national cross-sectional cohort represents a saturated share of patients needing access to spasticity chemodenervation therapy. Future studies should venture to confirm whether findings are limited to this specialization, and strategies to improve access for these underserved communities should be explored.

Risk Stratification and Cardiac Sympathetic Activity Assessment Using Myocardial [123I] MIBG Imaging in Renal Denervation. / Estratificação de Risco e Avaliação da Atividade Simpática Cardíaca Utilizando Imagem Miocárdica com [123I] MIBG na Denervação Renal.

Hyperactivation of the sympathetic nervous system plays a central role in the pathophysiology of hypertension. The aim of this study was to assess cardiac sympathetic activity and investigate the role of myocardial123I-labelled meta-iodo benzyl guanidine ([123I] MIBG) scintigraphy in cardiovascular risk stratification of patients with resistant hypertension treated with renal denervation (RDN). Eighteen patients were included in this prospective study (mean age 56 ± 10 years old, 27.8% females). Transthoracic echocardiogram, general blood analysis and myocardial ([123I] MIBG scintigraphy were performed before and six-months after RDN. A patient was considered a responder (R) if a drop ≥ 5mmHg on mean systolic ambulatory blood pressure (BP) monitoring was observed at the six-month follow-up. 66.7% of patients were R (drop in systolic BP of 20.6 ± 14.5mmHg, vs minus 8 ± 11.6mmHg in non-responders (NR), p=0.001). Early heart-mediastinum ratio (HMR) was significantly lower at baseline in the R group (1.6 ± 0.1 vs 1.72 ± 0.1, p<0.02) but similar at six months. Considering both instants in time, the R group had lower early HMR values than the NR group (p<0.05). Both the late HMR and the washout rate were identical and no significant correlation between response to RDN or any MIBG imaging index was found. Renal denervation effectively lowered blood pressure in the majority of patients but [123I] MIBG was not useful in predicting the response. However, there was evidence of sympathetic overdrive and, both early and late HMR were overall reduced, probably putting this population at a higher risk of adverse events.

A hiperativação do sistema nervoso simpático desempenha um papel central na fisiopatologia da hipertensão. O objetivo deste estudo foi avaliar a atividade simpática cardíaca e investigar o papel da cintigrafia miocárdica com metaiodobenzilguanidina com 123I ([123I] MIBG) na estratificação de risco cardiovascular de pacientes com hipertensão resistente tratados com denervação renal (DR). Dezoito pacientes foram incluídos neste estudo prospectivo (média de idade de 56 ± 10 anos, 27,8% mulheres). Ecocardiograma transtorácico, análise geral do sangue e cintilografia miocárdica com [(123I) MIBG] foram realizados antes e seis meses após a DR. Um paciente era considerado respondedor (R) se uma diminuição ≥ 5 mmHg na pressão arterial sistólica (PAS) média ambulatorial fosse observada no seguimento de seis meses. 66,7% dos pacientes foram R (diminuição na PAS de 20,6 ± 14,5 mmHg, vs. menos 8 ± 11,6 mmHg em não-respondedores (NR), p = 0,001). A relação coração-mediastino (RCM) inicial foi significativamente menor na linha basal no grupo R (1,6 ± 0,1 vs. 1,72 ± 0,1, p <0,02), mas semelhante em seis meses. Considerando os dois momentos no tempo, o grupo R teve valores iniciais de RCM mais baixos do que o grupo NR (p <0,05). Tanto o RCM tardio quanto a taxa de washout foram idênticos e nenhuma correlação significativa entre a resposta à DR ou qualquer índice de imagem com MIBG foi encontrada. A denervação renal efetivamente reduziu a pressão arterial na maioria dos pacientes, mas a imagem com [123I] MIBG não foi útil na previsão da resposta. Entretanto, houve evidência de overdrive do sistema nervoso simpático e, tanto a RCM inicial quanto tardia estavam reduzidas em geral, provavelmente colocando essa população em um risco maior de eventos adversos.

Assessment of arterial stiffness to predict blood pressure response to renal sympathetic denervation.

BACKGROUND: Recent trials support the efficacy of renal sympathetic denervation (RDN) to reduce blood pressure (BP). Nevertheless, about one third of patients are considered non-responders to RDN. Previous retrospective analyses suggest arterial stiffness could predict BP response to RDN. AIMS: We prospectively assessed the potential of invasive pulse wave velocity (iPWV) to predict BP response to RDN. Additionally, we aimed to establish non-invasive models based on arterial stiffness to predict BP response to RDN. METHODS:  iPWV, magnetic resonance imaging-based markers of arterial stiffness and the carotid-femoral pulse wave velocity were recorded prior to RDN in patients with treatment resistant hypertension. Changes in daytime BP after 3 months were analysed according to the prespecified iPWV cut-off (14.4 m/s). Regression analyses were used to establish models for non-invasive prediction of BP response. Results were compared to iPWV as reference and were then validated in an external patient cohort. RESULTS: Eighty patients underwent stiffness assessment before RDN. After 3 months, systolic 24h and daytime BP were reduced by 13.6±9.8 mmHg and 14.7±10.6 mmHg in patients with low iPWV, versus 6.2±13.3 mmHg and 6.3±12.8 mmHg in those with high iPWV (p<0.001 for both). Upon regression analysis, logarithmic ascending aortic distensibility and systolic baseline BP independently predicted BP change at follow-up. Both were confirmed in the validation cohort. CONCLUSIONS:  iPWV is an independent predictor for BP response after RDN. In addition, BP change prediction following RDN using non-invasive measures is feasible. This could facilitate patient selection for RDN treatment.

Equivalent Outcomes of Lumbar Therapeutic Facet Joint Nerve Blocks and Radiofrequency Neurotomy: Comparative Evaluation of Clinical Outcomes and Cost Utility.

BACKGROUND: Chronic low back pain secondary to facet joint pathology is prevalent in 27% to 40% of selected populations using controlled comparative local anesthetic blocks. Lumbar facet joint nerve blocks and radiofrequency neurotomy are the most common interventional procedures for lower back pain. Nonetheless, questions remain regarding the effectiveness of each modality. Moreover, there is no agreement in reference to superiority or inferiority of lumbar facet joint nerve blocks when compared with radiofrequency neurotomy. Centers for Medicare and Medicaid Services (CMS) and almost all payers prefer radiofrequency ablation. Both procedures have been extensively studied with randomized controlled trials, systematic reviews, and cost utility analysis. OBJECTIVE: To assess the clinical outcomes and cost utility of therapeutic lumbar facet joint nerve blocks (lumbar facet joint nerve blocks with L5 dorsal ramus block) compared with radiofrequency neurotomy in managing chronic low back pain of facet joint origin. STUDY DESIGN: A retrospective, case-control, comparative evaluation of outcomes and cost utility. SETTING: The study was conducted in an interventional pain management practice, a specialty referral center, a private practice setting in the United States. METHODS: The study was performed utilizing the Strengthening the Reporting of Observational Studies in Epidemiology Analysis (STROBE) criteria. Only the patients meeting the diagnostic criteria of facet joint pain by means of comparative, controlled diagnostic local anesthetic blocks were included.The main outcome measure was pain relief measured by the Numeric Rating Scale (NRS) evaluated at 3, 6, and 12 months. Significant improvement was defined as at least 50% improvement in pain relief. Cost utility was calculated utilizing direct payment data for the procedures with the addition of estimated indirect costs over a period of one year based on highly regarded surgical literature and previously published interventional pain management literature. RESULTS: A total of 326 patients met the inclusion criteria with 99 patients receiving lumbar facet joint nerve blocks (lumbar facet joint nerve blocks with L5 dorsal ramus block) and 227 receiving lumbar radiofrequency neurotomy. Forty-eight patients in the facet joint nerve block group and 148 patients in the radiofrequency group completed one-year follow-up. Patients experienced significant improvement in both groups from baseline to 12 months with significant pain relief (≥ 50%) Significant pain relief was recorded in 100%, 99%, and 79% of the patients in the facet joint nerve block group, whereas, it was 100%, 74%, and 65% in the radiofrequency neurotomy group at the 3, 6, and 12 month follow-up, with a significant difference at 6 months. Cost utility analysis showed average costs for quality-adjusted life year (QALY) of $4,664 for lumbar facet joint nerve blocks and $5,446 for lumbar radiofrequency neurotomy. Twelve patients (12%) in the lumbar facet joint nerve block group and 79 patients (35%) in the lumbar radiofrequency group were converted to other treatments, either due to side effects or inadequate relief. CONCLUSION: This study shows similar outcomes of therapeutic lumbar facet joint nerve blocks when compared with radiofrequency neurotomy as indicated by significant pain relief and cost utility.

Outcomes of Cervical Therapeutic Medial Branch Blocks and Radiofrequency Neurotomy: Clinical Outcomes and Cost Utility are Equivalent.

BACKGROUND: Cervical facet joint pain is often managed with either cervical radiofrequency neurotomy, cervical medial branch blocks, or cervical intraarticular injections. However, the effectiveness of each modality continues to be debated. Further, there is no agreement in reference to superiority or inferiority of facet joint nerve blocks compared to radiofrequency neurotomy, even though cervical facet joint radiofrequency neurotomy has been preferred by many and in fact, has been mandated by the Centers for Medicare and Medicaid Services (CMS), except when radiofrequency cannot be confirmed. Each procedure has advantages and disadvantages in reference to clinical utility, outcomes, cost utility, and side effect profile. However, comparative analysis has not been performed thus far in the literature in a clinical setting. STUDY DESIGN: A retrospective, case-control, comparative evaluation of outcomes and cost utility. SETTING: The study was conducted in an interventional pain management practice, a specialty referral center, a private practice setting in the United States. OBJECTIVE: To evaluate the clinical outcomes and cost utility of therapeutic medial branch blocks with radiofrequency neurotomy in managing chronic neck pain of facet joint origin. METHODS: The study was performed utilizing Strengthening the Reporting of Observational Studies in Epidemiology Analysis (STROBE) criteria. Only the patients meeting the diagnostic criteria of facet joint pain by means of comparative, controlled diagnostic local anesthetic blocks were included.The main outcome measure was pain relief measured by Numeric Rating Scale (NRS) evaluated at 3, 6, and 12 months. Significant improvement was defined as at least 50% improvement in pain relief. Cost utility was calculated with direct payment data for the procedures with addition of estimated indirect costs over a period of one year based on highly regarded surgical literature and previously published interventional pain management literature. RESULTS: Overall, 295 patients met inclusion criteria with 132 patients receiving cervical medial branch blocks and 163 patients with cervical radiofrequency neurotomy. One hundred and seven patients in the cervical medial branch group and 105 patients in the radiofrequency group completed one year follow-up. There was significant improvement in both groups from baseline to 12 months with pain relief and proportion of patients with >= 50% pain relief. Average relief of each procedure for cervical medial branch blocks was 13 to 14 weeks, whereas for radiofrequency neurotomy, it was 20 to 25 weeks. Significant pain relief was recorded in 100%, 94%, and 81% of the patients in the medial branch blocks group, whereas it was 100%, 69%, and 64% in the radiofrequency neurotomy group at 3, 6, and 12 month follow-up, with significant difference at 6 and 12 months.Cost utility analysis showed average cost for quality-adjusted life year (QALY) of $4,994 for cervical medial branch blocks compared to $5,364 for cervical radiofrequency neurotomy. Six of 132 patients (5%) in the cervical medial branch group and 53 of 163 (33%) patients in the cervical radiofrequency neurotomy group were converted to other treatments, either due to side effects (6 patients or 4%) or inadequate relief (47 patients or 29%). CONCLUSION: In this study, outcomes of cervical therapeutic medial branch blocks compared to radiofrequency neurotomy demonstrated significantly better outcomes with significant pain relief with similar costs for both treatments over a period of one year.

Suspensory ligament size does not change after plantar fasciotomy and neurectomy of the deep branch of the lateral plantar nerve by ultrasonographic assessment.

OBJECTIVE: To determine the short-term effect of plantar fasciotomy and neurectomy (PFN) of the deep branch of the lateral plantar nerve on the proximal suspensory ligament (PSL) cross-sectional area (CSA) in horses with hindlimb proximal suspensory desmopathy (PSD). STUDY DESIGN: Analytical, observational, cohort study. SAMPLE POPULATION: Twenty-one horses. METHODS: Records of horses with chronic PSD treated by PFN were included if a preoperative ultrasonographic examination was available and at least one postoperative ultrasonographic examination. One masked observer measured the ultrasonographic cross-sectional area (CSA) of the PSL. Intraobserver reliability was determined by repeatedly measuring a subset of ultrasonographic images (n = 127). Two masked observers measured the cross-sectional area of the proximal suspensory ligament (PSL-CSA) on preoperative proton density (PD)-weighted transverse high field magnetic resonance images (n = 19 horses) . Agreements for PSL-CSA between preoperative ultrasonographic and MRI measures and between the two magnetic resonance imaging (MRI) observers were assessed. Follow up considered the horses' ability to return to exercise and their owners' satisfaction. RESULTS: The reliability of the ultrasonographic measurement of the PSL-CSA was excellent. Agreement between ultrasonographic assessment and MRI assessment of PSL-CSA was good. No difference was detected between preoperative (median, interquartile range; oblique-incidence, 2.07, 1.72-2.55; on-incidence, 2.23, 1.98-2.65) and postoperative (oblique-incidence, 2.08, 1.80-2.74; on-incidence, 2.28, 2.01-2.74) PSL-CSAs. At a median of 12 months (4-33 months), 16/20 (80%) owners reported the horse was "better" and 15/20 (75%) functioned at or above preoperative levels. CONCLUSION: Ultrasonographic measurement of the PSL-CSA was reproducible and in good agreement with MRI measurement. The PSL-CSA was not influenced by PFN. CLINICAL SIGNIFICANCE: The PSL-CSA cannot be used to guide return to function.

Ultrasound-Guided Injection Treatments Versus Surgical Neurectomy for Morton Neuroma: A Cost-Effectiveness Analysis.

BACKGROUND. Morton neuroma is a common, painful disorder of the foot with multiple treatment options of varying cost and effectiveness. OBJECTIVE. The aim of this study was to determine the most cost-effective treatment pathway for symptomatic Morton neuromas when conservative management has failed. METHODS. An incremental cost-utility analysis was performed comparing a direct to surgical neurectomy strategy with three selective injection strategies in which one or more ultrasound-guided injection therapies was tried first before surgery for patients who did not respond to treatment. The three selective injection strategies were selective steroid injection, selective alcohol injection, and selective steroid/alcohol injection in which both steroid injections and alcohol sclerosing injections were trialed successively before surgical neurectomy. The direct-to-surgery approach was compared with the three different selective injection strategies and with a no-treatment strategy in a decision-analytic model for a hypothetical group of patients with symptomatic Morton neuroma in whom conservative management had failed. Model parameters, including treatment costs, effectiveness, complication rates, and health utility states, were estimated from the literature, reimbursement databases, and expert opinion. The outcome was cost per quality-adjusted life year (QALY) with a time horizon of 3 years. A societal cost perspective was adopted with a willingness-to-pay threshold of $100,000/QALY. Sensitivity analyses for key model parameters were performed. RESULTS. For the base input values, the steroid/alcohol selective injection strategy was dominant and yielded an incremental cost-effectiveness ratio of $4401.61/QALY compared with no treatment. The probabilistic sensitivity analysis supported this strategy in 74% of 10,000 simulated trials. Results were robust with low sensitivity to most input parameters. However, when the probability of successful alcohol injection treatment dropped below 40%, the steroid selective injection strategy became most cost-effective. CONCLUSION. A trial of ultrasound-guided injection therapies for Morton neuroma is a cost-effective strategy compared with proceeding directly to surgical neurectomy. CLINICAL IMPACT. Ultrasound-guided injection therapies are indicated as first-line treatment of patients with symptomatic Morton neuromas when conservative management fails.

Skin biopsy and quantitative sensory assessment in an Italian cohort of ATTRv patients with polyneuropathy and asymptomatic carriers: possible evidence of early non-length dependent denervation.

AIM: Study of intraepidermal nerve fiber density (IENFD) by skin biopsy represents a promising tool in the evaluation of patients with ATTRv polyneuropathy (ATTRv-PN). Herein, we retrospectively analyze intraepidermal innervation and quantitative sensory test (QST) data from an Italian cohort of Italian ATTRv-PN patients and asymptomatic carriers aimed to provide insights into early nerve pathological and functional changes in this disease. METHODS: IENFD and QST data of 14 ATTRv-PN patients and 14 asymptomatic carriers were retrospectively analyzed together with clinical and paraclinical data such as disease stage and severity, neuropathic pain scales, and sural SNAP amplitude. RESULTS: Given an estimated time to the predicted age of onset of symptomatic disease of 20.27 + / - 7.9 years, small nerve fiber loss seems to be unexpectedly early in carriers. Moreover, carriers showed skin denervation at the proximal (thigh) site, suggesting a non-length-dependent neuropathic process. IENFD at ankle correlated with disease severity and other paraclinical variables such as sural nerve potential amplitude and QST parameters. Patients at earlier stages of the disease did not show significant differences in ankle IENFD compared with asymptomatic carriers, but significant differences in terms of QST parameters, small fiber neuropathy symptoms, and neuropathic pain. CONCLUSIONS: Skin biopsy can disclose an early non-length-dependent small fiber loss in ATTRv-PN and, together with QST, could provide a useful insight disease onset and progression.

Estratificação de Risco e Avaliação da Atividade Simpática Cardíaca Utilizando Imagem Miocárdica com [123I] MIBG na Denervação Renal / Risk Stratification and Cardiac Sympathetic Activity Assessment Using Myocardial [123I] MIBG Imaging in Renal Denervation

Resumo A hiperativação do sistema nervoso simpático desempenha um papel central na fisiopatologia da hipertensão. O objetivo deste estudo foi avaliar a atividade simpática cardíaca e investigar o papel da cintigrafia miocárdica com metaiodobenzilguanidina com 123I ([123I] MIBG) na estratificação de risco cardiovascular de pacientes com hipertensão resistente tratados com denervação renal (DR). Dezoito pacientes foram incluídos neste estudo prospectivo (média de idade de 56 ± 10 anos, 27,8% mulheres). Ecocardiograma transtorácico, análise geral do sangue e cintilografia miocárdica com [(123I) MIBG] foram realizados antes e seis meses após a DR. Um paciente era considerado respondedor (R) se uma diminuição ≥ 5 mmHg na pressão arterial sistólica (PAS) média ambulatorial fosse observada no seguimento de seis meses. 66,7% dos pacientes foram R (diminuição na PAS de 20,6 ± 14,5 mmHg, vs. menos 8 ± 11,6 mmHg em não-respondedores (NR), p = 0,001). A relação coração-mediastino (RCM) inicial foi significativamente menor na linha basal no grupo R (1,6 ± 0,1 vs. 1,72 ± 0,1, p <0,02), mas semelhante em seis meses. Considerando os dois momentos no tempo, o grupo R teve valores iniciais de RCM mais baixos do que o grupo NR (p <0,05). Tanto o RCM tardio quanto a taxa de washout foram idênticos e nenhuma correlação significativa entre a resposta à DR ou qualquer índice de imagem com MIBG foi encontrada. A denervação renal efetivamente reduziu a pressão arterial na maioria dos pacientes, mas a imagem com [123I] MIBG não foi útil na previsão da resposta. Entretanto, houve evidência de overdrive do sistema nervoso simpático e, tanto a RCM inicial quanto tardia estavam reduzidas em geral, provavelmente colocando essa população em um risco maior de eventos adversos.

Abstract Hyperactivation of the sympathetic nervous system plays a central role in the pathophysiology of hypertension. The aim of this study was to assess cardiac sympathetic activity and investigate the role of myocardial123I-labelled meta-iodo benzyl guanidine ([123I] MIBG) scintigraphy in cardiovascular risk stratification of patients with resistant hypertension treated with renal denervation (RDN). Eighteen patients were included in this prospective study (mean age 56 ± 10 years old, 27.8% females). Transthoracic echocardiogram, general blood analysis and myocardial ([123I] MIBG scintigraphy were performed before and six-months after RDN. A patient was considered a responder (R) if a drop ≥ 5mmHg on mean systolic ambulatory blood pressure (BP) monitoring was observed at the six-month follow-up. 66.7% of patients were R (drop in systolic BP of 20.6 ± 14.5mmHg, vs minus 8 ± 11.6mmHg in non-responders (NR), p=0.001). Early heart-mediastinum ratio (HMR) was significantly lower at baseline in the R group (1.6 ± 0.1 vs 1.72 ± 0.1, p<0.02) but similar at six months. Considering both instants in time, the R group had lower early HMR values than the NR group (p<0.05). Both the late HMR and the washout rate were identical and no significant correlation between response to RDN or any MIBG imaging index was found. Renal denervation effectively lowered blood pressure in the majority of patients but [123I] MIBG was not useful in predicting the response. However, there was evidence of sympathetic overdrive and, both early and late HMR were overall reduced, probably putting this population at a higher risk of adverse events.

Cost-effectiveness of Radiofrequency Denervation for Zygapophyseal Joint Pain.

BACKGROUND: Chronic pain is a leading cause of disability. Radiofrequency denervation (RFD) is effective when performed according to guidelines for patients with correctly diagnosed zygapophyseal joint pain (ZJP). However, the cost-effectiveness of this method has not been fully explored. OBJECTIVE: The aim of this study was to analyze whether RFD is cost-effective for ZJP from a societal perspective. STUDY DESIGN: Cost effectiveness study based on an observational study. SETTING: An interventional pain management clinic in central Sweden. METHODS: Patients - This cost-effectiveness study was performed for all patients (n = 873) assessed between 2010 and 2016 at a specialized interventional pain clinic in Sweden. Those diagnosed with ZJP (n = 331, 37.9%) were treated with RFD and followed up for 1 year after the RFD. Using data collected from national registers, we determined the health care costs, medication costs, the patients' time and travel costs, and the patients' ability to work. The effects of RFD on quality-adjusted life years (QALY) and cost/QALY gained were calculated. RESULTS: On average, patients reported very low health-related quality of life (HRQoL; EQ-5D index: 0.212). After RFD, HRQoL increased significantly to 0.530 (P < 0.0001). Drug consumption and specialized health care consumption were reduced by 54% and 81%, respectively, and the cost/QALY gained from a societal perspective was 221,324 Swedish krona (USD ~26,008). The sensitivity analysis showed that the treatment was cost-effective in all scenarios evaluated, using the patients as their own controls. The cost/QALY gained from a health care perspective was 72,749 Swedish krona (USD ~8,548). LIMITATIONS: The results are based on data collected at one center. The results need to be compared with those from pain rehabilitation programs and should be confirmed using data from other centers. CONCLUSIONS: Patients referred for RFD in Sweden report extremely low HRQoL. HRQoL significantly increased following RFD in patients with ZJP. Medications and health care consumption decreased after RFD. RFD was cost-effective, and the sensitivity analysis yielded stable results in different scenarios. Therefore, RFD is a cost-effective treatment that meets the Swedish National Board of Health and Welfare criteria for a high priority treatment. TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (NCT01835704) with Protocol ID SE-Dnr-2012-446-31M-1.  https://clinicaltrials.gov/ct2/show/NCT01835704.

Facial Nerve Neurophysiologic Assessment in Vestibular Schwannoma Removal with Transcanal Approach: A Pilot Clinical Study.

BACKGROUND: The transcanal transpromontorial approach has been introduced to remove vestibular schwannomas. As with other techniques, preservation of the facial nerve (FN) is challenging. This pilot study described FN outcomes of patients preoperatively and postoperatively assessed with electromyography (EMG) and blink reflex (BR). METHODS: Between September 2017 and December 2018, 10 patients (5 men; 5 women; mean age, 59.8 years; age range, 25-77 years) underwent removal of vestibular schwannoma via the transcanal transpromontorial approach. FN assessment using EMG/BR and clinical evaluation with the House-Brackmann (HB) grading scale was performed preoperatively and 2 months postoperatively. If facial impairment was present postoperatively, further analysis was performed 6 months after surgery. RESULTS: All 10 patients had normal FN function on preoperative EMG/BR. After 2 months, 4 patients had normal FN function on EMG/BR, 4 patients showed a slight delay of FN responses, 1 patient had moderate dysfunction, and 1 patient had consistent damage. After 6 months, among the 6 patients with a pathologic neurophysiologic study, consistent EMG/BR improvement was shown, with complete recovery in 3 cases. At the last follow-up, 8 patients had HB grade I, 1 patient had HB grade II, and 1 patient had HB grade III in 1, showing progression toward healing in 9 of 10 cases. CONCLUSIONS: The transcanal transpromontorial approach is an effective procedure for vestibular schwannoma removal. EMG/BR represents an objective evaluation method to verify FN recovery after surgery and confirms the low impact of this surgical procedure on the FN.

Terminology and Legislation referring to Percutaneous Facet Procedures to Treat Low Back Pain in Brazil ­ Current Status

Incongruities in the terminology and in the Brazilian legislation about percutaneous facet procedures (PFPs) for the treatment of chronic lower back pain are frequently the subject of litigations between health professionals and supplementary healthcare providers. The Brazilian Hierarchical Classification of Medical Procedures (CBHPM, in the Portuguese acronym) describes four types of PFPs, while the Brazilian Unified Supplementary Health Terminology (TUSS, in the Portuguese acronym) describes five distinct lumbar PFPs, which correlate with the ones described on the List of Procedures and Events in Health, created by the Brazilian National Agency of Supplementary Health (ANS, in the Portuguese acronym). In the present paper, we review the terminology of the procedures, proposing the unification of the terminology and the abolition of redundancies in the tables. Finally, we developed a single terminology proposal for the PFPs based on their complexity and objectives to be used for the treatment of lower back pain.

Cost-Effectiveness of Radiofrequency Denervation for Patients With Chronic Low Back Pain: The MINT Randomized Clinical Trials.

OBJECTIVES: To evaluate the cost-effectiveness of radiofrequency denervation when added to a standardized exercise program for patients with chronic low back pain. METHODS: An economic evaluation was conducted alongside 3 pragmatic multicenter, nonblinded randomized clinical trials (RCTs) in The Netherlands with a follow up of 52 weeks. Eligible participants were included between January 1, 2013, and October 24, 2014, and had chronic low back pain; a positive diagnostic block at the facet joints (n = 251), sacroiliac (SI) joints (n = 228), or a combination of facet joints, SI joints, and intervertebral discs (n = 202); and were unresponsive to initial conservative care. Quality-adjusted life-years (QALYs) and societal costs were measured using self-reported questionnaires. Missing data were imputed using multiple imputation. Bootstrapping was used to estimate statistical uncertainty. RESULTS: After 52 weeks, no difference in costs between groups was found in the facet joint or combination RCT. The total costs were significantly higher for the intervention group in the SI joint RCT. The maximum probability of radiofrequency denervation being cost-effective when added to a standardized exercise program ranged from 0.10 in the facet joint RCT to 0.17 in the SI joint RCT irrespective of the ceiling ratio, and 0.65 at a ceiling ratio of €30 000 per QALY in the combination RCT. CONCLUSIONS: Although equivocal among patients with symptoms in a combination of the facet joints, SI joints, and intervertebral discs, evidence suggests that radiofrequency denervation combined with a standardized exercise program cannot be considered cost-effective from a societal perspective for patients with chronic low back pain originating from either facet or SI joints in a Dutch healthcare setting.

Update of Utilization Patterns of Facet Joint Interventions in Managing Spinal Pain from 2000 to 2018 in the US Fee-for-Service Medicare Population.

BACKGROUND: Interventional techniques for managing spinal pain, from conservative modalities to surgical interventions, are thought to have been growing rapidly. Interventional techniques take center stage in managing chronic spinal pain. Specifically, facet joint interventions experienced explosive growth rates from 2000 to 2009, with a reversal of these growth patterns and in some settings, a trend of decline after 2009. OBJECTIVES: The objectives of this assessment of utilization patterns include providing an update of facet joint interventions in managing chronic spinal pain in the fee-for-service (FFS) Medicare population of the United States from 2000 to 2018. STUDY DESIGN: The study was designed to assess utilization patterns and variables of facet joint interventions in managing chronic spinal pain from 2000 to 2018 in the FFS Medicare population in the United States. METHODS: Data for the analysis were obtained from the master database from the Centers for Medicare & Medicaid Services (CMS) physician/supplier procedure summary from 2000 to 2018. RESULTS: Facet joint interventions increased 1.9% annually and 18.8% total from 2009 to 2018 per 100,000 FFS Medicare population compared with an annual increase of 17% and overall increase of 309.9% from 2000 to 2009. Lumbosacral facet joint nerve block sessions or visits decreased at an annual rate of 0.2% from 2009 to 2018, with an increase of 15.2% from 2000 to 2009. In contrast, lumbosacral facet joint neurolysis sessions increased at an annual rate of 7.4% from 2009 to 2018, and the utilization rate also increased at an annual rate of 23.0% from 2000 to 2009. The proportion of lumbar facet joint blocks sessions to lumbosacral facet joint neurolysis sessions changed from 6.7 in 2000 to 1.9 in 2018. Cervical and thoracic facet joint injections increased at an annual rate of 0.5% compared with cervicothoracic facet neurolysis sessions of 8.7% from 2009 to 2018. Cervical facet joint injections increased to 4.9% from 2009 to 2018 compared with neurolysis procedures of 112%. The proportion of cervical facet joint injection sessions to neurolysis sessions changed from 8.9 in 2000 to 2.4 in 2018. LIMITATIONS: This analysis is limited by inclusion of only the FFS Medicare population, without adding utilization patterns of Medicare Advantage plans, which constitutes almost 30% of the Medicare population. The utilization data for individual states also continues to be sparse and may not be accurate. CONCLUSIONS: Utilization patterns of facet joint interventions increased 1.9% per 100,000 Medicare population from 2009 to 2018. This results from an annual decline of - 0.2% lumbar facet joint injection sessions but with an increase of facet joint radiofrequency sessions of 7.4%. KEY WORDS: Interventional techniques, facet joint interventions, facet joint nerve blocks, facet joint neurolysis.

Cooled radiofrequency ablation of the genicular nerves for chronic pain due to osteoarthritis of the knee: a cost-effectiveness analysis based on trial data.

BACKGROUND: For patients with painful knee osteoarthritis, long-term symptomatic relief may improve quality of life. Cooled radiofrequency ablation (CRFA) has demonstrated significant improvements in pain, physical function and health-related quality of life compared with conservative therapy with intra-articular steroid (IAS) injections. This study aimed to establish the cost-effectiveness of CRFA compared with IAS for managing moderate to severe osteoarthritis-related knee pain, from the US Medicare system perspective. METHODS: We conducted a cost-effectiveness analysis utilizing efficacy data (Oxford Knee Scores) from a randomized, crossover trial on CRFA (NCT02343003), which compared CRFA with IAS out to 6 and 12 months, and with IAS patients who subsequently crossed over to receive CRFA after 6 months. Outcomes included health benefits (quality-adjusted life-years [QALYs]), costs and cost-effectiveness (expressed as cost per QALY gained). QALYs were estimated by mapping Oxford Knee Scores to the EQ-5D generic utility measure using a validated algorithm. Secondary analyses explored differences in the settings of care and procedures used in-trial versus real-world clinical practice. RESULTS: CRFA resulted in an incremental QALY gain of 0.091 at an incremental cost of $1711, equating to a cost of US$18,773 per QALY gained over a 6-month time horizon versus IAS. Over a 12-month time horizon, the incremental QALY gain was 0.229 at the same incremental cost, equating to a cost of US$7462 per QALY gained versus IAS. Real-world cost assumptions resulted in modest increases in the cost per QALY gained to a maximum of US$21,166 and US$8296 at 6 and 12 months, respectively. Sensitivity analyses demonstrated that findings were robust to variations in efficacy and cost parameters. CONCLUSIONS: CRFA is a highly cost-effective treatment option for patients with osteoarthritis-related knee pain, compared with the US$100,000/QALY threshold typically used in the US.

Prospective Clinical Trial Comparing Trapezial Denervation With Trapeziectomy for the Surgical Treatment of Arthritis at the Base of the Thumb.

BACKGROUND: Trapeziectomy is considered to be the "gold standard" procedure for first carpometacarpal joint (first CMCJ) osteoarthritis. First CMCJ denervation offers the potential benefit of a shorter procedure with bone and joint preservation and swift postoperative rehabilitation. This trial aimed to compare functional outcomes, patient satisfaction, quality of life, and cost effectiveness following these treatments. METHODS: This study was a prospective clinical trial commencing December 2005 to November 2013. A range of functional outcomes assessments were used preoperatively at 6 and 12 mo and 5 y after surgery. These included measurements of strength/motion, visual analogue score, Michigan Hand Outcomes and the European Quality of Life-5 Dimensions questionnaires. Data were analyzed using a two-sample t-test and Mann-Whitney test. RESULTS: A total of 45 patients were studied of 55 recruited. Age ranged from 41 to 72 (mean = 59). Thirty-five patients underwent denervation and 10 initially had trapeziectomy. Nine patients were converted to trapeziectomy within an average of 6 to 12 mo. There was no significant difference in the functional outcomes at different points of follow-ups. Similarly, there was no significant difference in the time of return to work or cost effectiveness. Denervation achieved a success rate of just above 70%, whereas no revisions were required for the trapeziectomy group. CONCLUSIONS: There was no difference between the two treatments. First CMCJ denervation does not appear to be superior to trapeziectomy. However, the advantage of rapid rehabilitation makes it more favored by patients but at the expense of 30% reoperation rate. LEVEL OF EVIDENCE: Level II.

Assessment of metal concentrations in the SOD1G93A mouse model of amyotrophic lateral sclerosis and its potential role in muscular denervation, with particular focus on muscle tissue.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is among the most common of the motor neuron diseases, and arguably the most devastating. During the course of this fatal neurodegenerative disorder, motor neurons undergo progressive degeneration. The currently best-understood animal models of ALS are based on the over-expression of mutant isoforms of Cu/Zn superoxide dismutase 1 (SOD1); these indicate that there is a perturbation in metal homeostasis with disease progression. Copper metabolism in particular is affected in the central nervous system (CNS) and muscle tissue. METHODS: This present study assessed previously published and newly gathered concentrations of transition metals (Cu, Zn, Fe and Se) in CNS (brain and spinal cord) and non-CNS (liver, intestine, heart and muscle) tissues from transgenic mice over-expressing the G93A mutant SOD1 isoform (SOD1G93A), transgenic mice over-expressing wildtype SOD1 (SOD1WT) and non-transgenic controls. RESULTS: Cu accumulates in non-CNS tissues at pre-symptomatic stages in SOD1G93A tissues. This accumulation represents a potentially pathological feature that cannot solely be explained by the over-expression of mSOD1. As a result of the lack of Cu uptake into the CNS there may be a deficiency of Cu for the over-expressed mutant SOD1 in these tissues. Elevated Cu concentrations in muscle tissue also preceded the onset of symptoms and were found to be pathological and not be the result of SOD1 over-expression. CONCLUSIONS: It is hypothesized that the observed Cu accumulations may represent a pathologic feature of ALS, which may actively contribute to axonal retraction leading to muscular denervation, and possibly significantly contributing to disease pathology. Therefore, it is proposed that the toxic-gain-of-function and dying-back hypotheses to explain the molecular drivers of ALS may not be separate, individual processes; rather our data suggests that they are parallel processes.

Clinical assessment of diode laser-assisted endoscopic intrasphenoidal vidian neurectomy in the treatment of refractory rhinitis.

For chronic rhinitis that is refractory to medical therapy, surgical intervention such as endoscopic vidian neurectomy (VN) can be used to control the intractable symptoms. Lasers can contribute to minimizing the invasiveness of ENT surgery. The aim of this retrospective study is to compare in patients who underwent diode laser-assisted versus traditional VN in terms of operative time, surgical field, quality of life, and postoperative complications. All patients had refractory rhinitis with a poor treatment response to a 6-month trial of corticosteroid nasal sprays and underwent endoscopic VN between November 2006 and September 2015. They were non-randomly allocated into either a cold instrument group or a diode laser-assisted group. Vidian nerve was excised with a 940-nm continuous wave diode laser through a 600-µm silica optical fiber, utilizing a contact mode with the power set at 5 W. A visual analog scale (VAS) was used to grade the severity of the rhinitis symptoms for quality of life assessment before the surgery and 6 months after. Of the 118 patients enrolled in the study, 75 patients underwent cold instrument VN and 43 patients underwent diode laser-assisted VN. Patients in the laser-assisted group had a significantly lower surgical field score and a lower postoperative bleeding rate than those in the cold instrument group. Changes in the VAS were significant in preoperative and postoperative nasal symptoms in each group. The application of diode lasers for vidian nerve transection showed a better surgical field and a lower incidence of postoperative hemorrhage. Recent advancements in laser application and endoscopic technique has made VN safer and more effective. We recommend this surgical approach as a reliable and effective treatment for patients with refractory rhinitis.

Pulmonary vein isolation with concomitant renal artery denervation is associated with reduction in both arterial blood pressure and atrial fibrillation burden: Data from implantable cardiac monitor.

BACKGROUND: Renal artery denervation (RDN) has provided incremental atrial fibrillation (AF) suppression after pulmonary vein isolation (PVI) in patients with AF in the setting of drug-resistant hypertension. OBJECTIVE: To assess the relationship between changes of mean blood pressure (BP) and AF recurrences/AF burden after PVI combined with RDN. METHODS: All patients from two randomized studies with symptomatic paroxysmal AF and/or persistent AF and resistant hypertension who underwent PVI-only (n=37) or PVI with RDN (n=39), and implantable cardiac monitor (ICM) implantation were eligible for this study. Mixed-effects linear models were used to investigate the effect of RDN on mean BP and mean AF burden and associations between the two during the 12-month follow-up. RESULTS: Concomitant RDN was associated with a significant reduction in both mean AF burden (2.43 [95% CI: 1.76-3.09] % vs 6.95 [95% CI: 5.44-8.45] %) and mean BP (104 [95% CI: 103-106] mm Hg vs 112 [95% CI: 110-113] mm Hg). Decrease in mean BP was positively correlated with decline in mean AF burden: reduction of 5-10 mm Hg was accompanied by a 7.0% decreased mean AF burden, with greater reduction (up to 20 mm Hg) associated with on average 17.7% lower mean AF burden. CONCLUSIONS: Renal artery denervation when added to PVI decreases AF recurrences, AF burden, and mean BP. Reduction in mean BP is associated with both AF burden and recurrences. Further large-scale studies are needed to define the mechanistic pathway(s) of the antiarrhythmic effects of RDN.