D’Souza, Ryan S.

Objective Peripheral nerve stimulation (PNS) is an emerging neuromodulation modality, yet there remains limited data highlighting its long-term effectiveness. The objective of this study was to report real-world data on pain intensity and opioid consumption after temporary and permanent PNS for chronic pain up to 24 months postimplantation. Methods A retrospective study was conducted on all patients who received PNS implants at a multi-centered enterprise between January 1, 2014 and February 24, 2022. The two co-primary outcomes were: (1) change in pain intensity (11-point Numerical Rating Scale) from baseline to 12 months postimplant; and (2) comparison of the change in pain intensity between temporary and permanent PNS cohorts 12 months postimplant. Results 126 patients were included in this analysis. Pain intensity significantly decreased 12 months postimplant in the overall cohort (mean difference (MD) −3.0 (95% CI −3.5 to −2.4), p<0.0001). No significant difference in this reduction was identified between temporary and permanent PNS cohorts (MD 0.0 (95% CI −1.1 to 1.0), p=1.00) 12 months postimplantation. Pain intensity significantly decreased in the overall, temporary, and permanent cohorts at all secondary time points (3, 6, and 24 months). No change in daily opioid consumption was observed at 6 and 12 months postimplant in the overall cohort. Conclusion This study found that both temporary and permanent PNS may be effective for reducing pain intensity in patients with chronic pain up to 24 months postimplantation, although no changes in opioid consumption were observed. The decrease in pain intensity was comparable between patients receiving temporary versus permanent implants, highlighting that temporary PNS may achieve long-lasting clinical benefits. However, given the substantial loss to follow-up, further large-scale studies are needed to solidify conclusions about the efficacy of PNS.

Abstract Background Gabapentin, a widely prescribed medication for various neuropathic pain conditions, has demonstrated efficacy in managing diverse neurological disorders. While conventional side effects are well‐documented, a growing body of evidence suggests the existence of atypical side effects, necessitating comprehensive exploration. This paper aims to systematically review and summarize the literature on the atypical side effects of gabapentin, shedding light on manifestations beyond the conventional spectrum. Methods A systematic review was conducted, encompassing peer‐reviewed articles published up to the knowledge cutoff date in November 2023. Databases, specifically PubMed, were searched for relevant studies, focusing on atypical side effects such as myoclonus, ataxia, pediatric aggression, respiratory depression, pneumonia, pregnancy complications, sleep interference, encephalopathy, peripheral edema, suicidal ideation, dyskinesia, anorgasmia, and myopathy. Inclusion criteria comprised studies with a focus on gabapentin‐related atypical side effects, published in recognized journals and involving human subjects. Results The review identified a spectrum of atypical side effects associated with gabapentin use, ranging from neurological manifestations like myoclonus and ataxia to behavioral changes such as pediatric aggression and suicidal ideation. Additionally, respiratory complications, pregnancy‐related issues, sleep disturbances, and rare complications like encephalopathy and myopathy were observed. Literature synthesis provided insights into the incidence, clinical presentation, and potential mechanisms underlying these atypical side effects. Conclusion This comprehensive review highlights the diverse range of atypical side effects associated with gabapentin use, expanding beyond conventional knowledge. Healthcare practitioners must be cognizant of these manifestations, recognizing their potential impact on patient well‐being. As clinical decision‐making relies on a thorough understanding of a medication's side effect profile, this review contributes to enhancing awareness and fostering informed practices in the prescription and management of gabapentin. Further research is warranted to elucidate the mechanisms and risk factors associated with these atypical side effects, refining our understanding of gabapentin's safety profile.

Background The efficacy of spinal cord stimulation (SCS) in chronic pain studies is traditionally assessed by pain scores, which do not reflect the multidimensional nature of pain perception. Despite the evidence of SCS’s influence on emotional functioning comprehensive assessments of its effect remain lacking. Objective To assess changes in emotional and psychosocial functioning in patients who underwent SCS implantation for chronic pain. Evidence review Ovid MEDLINE, EMBASE, PsychINFO, Cochrane CENTRAL and Scopus databases were searched for original peer-reviewed publications reporting emotional functioning after SCS. The primary outcomes were a pooled mean difference (MD) in anxiety, depression, global functioning, mental well-being and pain catastrophizing at 12 months. The Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) was used to determine the quality of evidence. Findings Thirty-two studies were included in the primary analysis. Statistically significant improvements were observed in anxiety (MD −2.16; 95% CI −2.84 to −1.49; p<0.001), depression (MD −4.66; 95% CI −6.26 to −3.06; p<0.001), global functioning (MD 20.30; 95% CI 14.69 to 25.90; p<0.001), mental well-being (MD 4.95; 95% CI 3.60 to 6.31; p<0.001), and pain catastrophizing (MD −12.09; 95% CI −14.94 to −9.23; p<0.001). Subgroup analyses revealed differences in Global Assessment of Functioning and mental well-being based on study design and in depression based on waveform paradigm. Conclusion The results highlight the statistically and clinically significant improvements in emotional and psychosocial outcomes in patients with chronic pain undergoing SCS therapy. However, these results need to be interpreted with caution due to the very low certainty of evidence per the GRADE criteria. PROSPERO registration CRD42023446326.

Well-established guidelines and checklists for authors, reviewers, and readers of systematic reviews and scoping reviews are readily available. However, the availability of such for narrative reviews is lacking, including, but not limited to, field-specific guidelines in the field of anesthesia and pain medicine. In this brief article, we review the differences between the major types of reviews, followed by a more detailed description of narrative reviews that clearly differentiates them from other types of reviews. We include a recommended checklist that will aid producers, editors, reviewers, and consumers of narrative reviews as well as examples specific to the field of anesthesia and pain medicine. It is the hope that the guidelines recommended here will aid producers, editors, reviewers, and consumers of narrative reviews in anesthesia and pain medicine, including Regional Anesthesia & Pain Medicine. Adherence to such should help differentiate between narrative reviews and other types of reviews as well as provide consistency in what elements are necessary to include in a narrative review in the field of anesthesia and pain medicine.

AbstractBackgroundLumbar medial branch nerve radiofrequency ablation (LRFA) is an interventional procedure used to treat chronic lumbar facet joint pain. Because the medial branch nerves also innervate the multifidus muscle, it has been proposed that LRFA may pose a risk of multifidus atrophy and/or dysfunction. However, the quality and level of evidence to answer this clinical question have not been established. Therefore, this review aimed to systematically appraise the literature to discern whether the prevailing evidence substantiates the hypothesis in question.MethodsA systematic review compliant with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines was performed to evaluate the quality and level of evidence of studies reporting functional and/or structural changes in the multifidus muscle following LRFA.ResultsOnly five cohort studies met inclusion criteria. Two studies assessed changes in multifidus function following LRFA with confirmed denervation at electromyography and significant reduction in multifidus shear modulus with ultrasound shear wave elastography. Of the four studies that evaluated changes in multifidus structure with magnetic resonance imaging following LRFA, two demonstrated a decrease in cross‐sectional area or an increase in fat infiltration, one demonstrated no change, and one revealed an apparent increase. Given the destructive nature attributed to LRFA, some degree of multifidus atrophy and/or dysfunction may be plausible, albeit with a very low certainty that relies on a restricted body of literature of modest quality and with a presence of high bias.ConclusionThere is a paucity of studies discussing the potential association between LRFA and multifidus atrophy and/or dysfunction. In light of the shortage of high‐quality studies and the absence of standardized protocols to assess both changes in the structure and function of the multifidus subsequent to LRFA, there is a pressing need for more prospective studies with a high methodological rigor to comprehensively address and answer this enduring debate in clinical practice.

Abstract Objectives Lumbar spine surgery is a common procedure for treating disabling spine‐related pain. In recent decades, both the number and cost of spine surgeries have increased despite technological advances and modification in surgical technique. For those patients that have continued uncontrolled back and/or lower extremity pain following lumbar spine surgery, spinal cord stimulation (SCS) has emerged as a viable treatment option. However, the impact of lumbar spine surgical history remains largely unstudied. Specifically, the current study considers the impact of number of prior lumbar spine surgeries on pain relief outcomes following SCS implantation. Materials and Methods We queried the electronic medical record of five separate pain practices for all patients who have undergone a SCS implant between January 1, 2017, and March 1, 2020. Inclusion criteria consisted of any patients with an SCS implant who underwent a prior lumbar spine surgery. The primary outcome was the mean calculated percentage pain relief in patients based on number of prior lumbar spine surgeries. Results There was a total of 1974 total SCS implant cases identified across five separate pain clinics. There was no difference in mean calculated pain relief in patients with one prior spine surgery versus those with two or more prior spine surgeries (28.2% vs. 25.8%, adjusted β‐coefficient –3.1, 95% CI –8.9 to 2.7, p = 0.290). Similarly, when analyzing number of spine surgeries as a continuous variable, there was no association between number of spine surgeries and calculated pain relief (adjusted β‐coefficient –1.5, 95% CI –4.0 to 1.1, p = 0.257). Additionally, after patients were stratified based on waveform, there was no association between number of prior lumbar spine surgeries (analyzed both as a categorical and continuous variable) and calculated percentage pain relief. Conclusions This multicentered retrospective study found that there was no significant difference in pain scores in individuals who received SCS following one or more lumbar spine surgeries. Additionally, the waveform of the SCS device had no statistically significant impact on post‐operative pain scores following one or more lumbar spine surgeries.

Summary Non‐steroidal anti‐inflammatory drugs (NSAIDs) are one of the mainstays of multimodal pain management. While effective for acute pain control, recent pre‐clinical evidence has raised concerns regarding an association between NSAIDs and chronic pain and potential opioid use. Our objective was to explore the association between peri‐operative use of prescription NSAIDs and the need for continued opioid prescriptions lasting 90–180 days in previously opioid‐naïve patients undergoing total knee arthroplasty. A database of health claims in the USA was used to identify all opioid‐naïve adult patients who underwent primary knee arthroplasty between January 2010 and October 2021. We evaluated the magnitude of association between peri‐operative prescription NSAID claims and claims for opioids at 90 days postoperatively using multivariable logistic regression models. Secondary outcomes included: the magnitude of association between peri‐operative NSAID prescription and claims for opioids at 180 days postoperatively; and identifying other potential factors associated with opioid claims at 90 days postoperatively. After risk adjustment using multivariable logistic regression models in the 789,736‐patient cohort, the adjusted odds ratio (95%CI) for a continuous claim of opioids at 90 and 180 days postoperatively among patients with a peri‐operative NSAID prescription within 30 days was 1.32 (1.30–1.35), p < 0.001; and 1.12 (1.10–1.15), p < 0.001, respectively. This estimate of effect remained robust at 90 days after accounting for known potential confounders, including pre‐existing knee pain and acute postoperative pain severity. Similar analysis of other pain medications (e.g. paracetamol) did not detect such an association. This population‐based cohort study suggests that peri‐operative prescription NSAID use may be associated with continued opioid prescription claims at 90 and 180 days after knee arthroplasty, even after adjusting for other observed covariates for continuous opioid claims. These novel findings can inform clinical decision‐making for post‐surgical pain management, risk–benefit discussions with patients and future research.