The Neurostimulation Appropriateness Consensus Committee (NACC)®: Recommendations for Spinal Cord Stimulation Long-Term Outcome Optimization and Salvage Therapy.

INTRODUCTION: The International Neuromodulation Society (INS) has recognized a need to establish best practices for optimizing implantable devices and salvage when ideal outcomes are not realized. This group has established the Neurostimulation Appropriateness Consensus Committee (NACC)® to offer guidance on matters needed for both our members and the broader community of those affected by neuromodulation devices. MATERIALS AND METHODS: The executive committee of the INS nominated faculty for this NACC® publication on the basis of expertise, publications, and career work on the issue. In addition, the faculty was chosen in consideration of diversity and inclusion of different career paths and demographic categories. Once chosen, the faculty was asked to grade current evidence and along with expert opinion create consensus recommendations to address the lapses in information on this topic. RESULTS: The NACC® group established informative and authoritative recommendations on the salvage and optimization of care for those with indwelling devices. The recommendations are based on evidence and expert opinion and will be expected to evolve as new data are generated for each topic. CONCLUSIONS: NACC® guidance should be considered for any patient with less-than-optimal outcomes with a stimulation device implanted for treating chronic pain. Consideration should be given to these consensus points to salvage a potentially failed device before explant.

Complex Regional Pain Syndrome: Evidence-Based Advances in Concepts and Treatments.

PURPOSE OF REVIEW: This review presents the most current information about the epidemiology of complex regional pain syndrome (CRPS), classification and diagnostic criteria, childhood CRPS, subtypes, pathophysiology, conventional and less conventional treatments, and preventive strategies. RECENT FINDINGS: CRPS is a painful disorder with multifactorial pathophysiology. The data describe sensitization of the central and peripheral nervous systems, inflammation, possible genetic factors, sympatho-afferent coupling, autoimmunity, and mental health factors as contributors to the syndrome. In addition to conventional subtypes (type I and type II), cluster analyses have uncovered other proposed subtypes. Prevalence of CRPS is approximately 1.2%, female gender is consistently associated with a higher risk of development, and substantial physical, emotional, and financial costs can result from the syndrome. Children with CRPS seem to benefit from multifaceted physical therapy leading to a high percentage of symptom-free patients. The best available evidence along with standard clinical practice supports pharmacological agents, physical and occupational therapy, sympathetic blocks for engaging physical restoration, steroids for acute CRPS, neuromodulation, ketamine, and intrathecal baclofen as therapeutic approaches. There are many emerging treatments that can be considered as a part of individualized, patient-centered care. Vitamin C may be preventive. CRPS can lead to progressively painful sensory and vascular changes, edema, limb weakness, and trophic disturbances, all of which substantially erode healthy living. Despite some progress in research, more comprehensive basic science investigation is needed to clarify the molecular mechanisms of the disease so that targeted treatments can be developed for better outcomes. Incorporating a variety of standard therapies with different modes of action may offer the most effective analgesia. Introducing less conventional approaches may also be helpful when traditional treatments fail to provide sufficient improvement.

Review of the Current State of Urine Drug Testing in Chronic Pain: Still Effective as a Clinical Tool and Curbing Abuse, or an Arcane Test?

PURPOSE OF REVIEW: Therapeutic use, misuse, abuse, and diversion of controlled substances in managing chronic non-cancer pain remain a major concern for physicians, the government, payers, and patients. The challenge remains finding effective diagnostic tools that can be clinically validated to eliminate or substantially reduce the abuse of controlled prescription drugs, while still assuring the proper treatment of those patients in pain. Urine drug testing still remains an important means of adherence monitoring, but questions arise as to its relevance and effectiveness. This review examines the role of UDT, determines its utility in current clinical practice, and investigates its relevance in current chronic pain management. RECENT FINDINGS: A review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Literature was searched from year 2000 to present examining the relevance and role of UDT in monitoring chronic opioid therapy along with reliability and accuracy, appropriate use, overuse, misuse, and abuse. There are only a limited number of reviews and investigations on UDT, despite the fact that clinicians who prescribe controlled medications for chronic states commonly are expected to utilize UDT. Therefore, despite highly prevalent use, there is a limited publication base from which to draw in this present study. Regardless of experience or training background, physicians and healthcare providers can much more adequately assess opioid therapy with the aid of UDT, which often requires confirmatory testing by a laboratory for clinical and therapeutic prescribing decisions. It has become a strongly recommended aspect of pain care with controlled substances locally, regionally, and nationally. Incorporating UDT for all patients in whom chronic opioid therapy is undertaken is consistent with state and national guidelines and best practice strategies. Practice standards vary as to the frequency of UDT locally, regionally, and nationally, however.

The Neuromodulation Appropriateness Consensus Committee on Best Practices for Dorsal Root Ganglion Stimulation.

INTRODUCTION: The Neuromodulation Appropriateness Consensus Committee (NACC) is dedicated to improving the safety and efficacy of neuromodulation and thus improving the lives of patients undergoing neuromodulation therapies. With continued innovations in neuromodulation comes the need for evolving reviews of best practices. Dorsal root ganglion (DRG) stimulation has significantly improved the treatment of complex regional pain syndrome (CRPS), among other conditions. Through funding and organizational leadership by the International Neuromodulation Society (INS), the NACC reconvened to develop the best practices consensus document for the selection, implantation and use of DRG stimulation for the treatment of chronic pain syndromes. METHODS: The NACC performed a comprehensive literature search of articles about DRG published from 1995 through June, 2017. A total of 2538 article abstracts were then reviewed, and selected articles graded for strength of evidence based on scoring criteria established by the US Preventive Services Task Force. Graded evidence was considered along with clinical experience to create the best practices consensus and recommendations. RESULTS: The NACC achieved consensus based on peer-reviewed literature and experience to create consensus points to improve patient selection, guide surgical methods, improve post-operative care, and make recommendations for management of patients treated with DRG stimulation. CONCLUSION: The NACC recommendations are intended to improve patient care in the use of this evolving therapy for chronic pain. Clinicians who choose to follow these recommendations may improve outcomes.

Nanotechnology: A Promising New Paradigm for the Control of Pain.

Objective: The objective of this article is to critically review both preclinical and clinical studies that focus on the use of nanotechnology for both acute and chronic pain management, surveying both diagnostic and therapeutic applications. The article also provides information on nanotechnology for pain practitioners, so that they may better understand how this technology works and how it may be applied to their day-to-day clinical practice. Study Design: Narrative review. Methods: The Pubmed NCBI and EMBASE databases were utilized to review published reports of in vivo and clinical studies that focus on using nanotechnology for pain management applications in both the acute and chronic pain settings. Results: Articles were screened by title, abstract, and full article review. They were then analyzed by specific clinical indications, and appropriate data were presented based on a critical analysis of those articles. Conclusions: As the development of nanomedical applications in acute and chronic pain management continues, medical practitioners should consider their growing potential to enhance the care of patients who are consistently living with pain. Current barriers to implementation include manufacturing scale-up for commercial viability, long-term nanoparticle toxicity considerations, and high cost for successful passage through clinical trials. These challenges will need to be overcome with ongoing translational research efforts in collaboration with industry and government bodies such as the Food and Drug Administration (FDA).

Spinal Cord Stimulation for Treating Chronic Pain: Reviewing Preclinical and Clinical Data on Paresthesia-Free High-Frequency Therapy.

BACKGROUND: Traditional spinal cord stimulation (SCS) requires that paresthesia overlaps chronic painful areas. However, the new paradigm high-frequency SCS (HF-SCS) does not rely on paresthesia. STUDY DESIGN: A review of preclinical and clinical studies regarding the use of paresthesia-free HF-SCS for various chronic pain states. METHODS: We reviewed available literatures on HF-SCS, including Nevro's paresthesia-free ultra high-frequency 10 kHz therapy (HF10-SCS). Data sources included relevant literature identified through searches of PubMed, MEDLINE/OVID, and SCOPUS, and manual searches of the bibliographies of known primary and review articles. OUTCOME MEASURES: The primary goal is to describe the present developing conceptions of preclinical mechanisms of HF-SCS and to review clinical efficacy on paresthesia-free HF10-SCS for various chronic pain states. RESULTS: HF10-SCS offers a novel pain reduction tool without paresthesia for failed back surgery syndrome and chronic axial back pain. Preclinical findings indicate that potential mechanisms of action for paresthesia-free HF-SCS differ from those of traditional SCS. CONCLUSIONS: To fully understand and utilize paresthesia-free HF-SCS, mechanistic study and translational research will be very important, with increasing collaboration between basic science and clinical communities to design better trials and optimize the therapy based on mechanistic findings from effective preclinical models and approaches. Future research in these vital areas may include preclinical and clinical components conducted in parallel to optimize the potential of this technology.

Review of Recent Advances in Peripheral Nerve Stimulation (PNS).

Peripheral nerve stimulation (PNS) for the treatment of chronic pain has become an increasingly important field in the arena of neuromodulation, given the ongoing advances in electrical neuromodulation technology since 1999 permitting minimally invasive approaches using an percutaneous approach as opposed to implantable systems. Our review aims to provide clinicians with the recent advances and studies in the field, with specific emphasis on clinical data and indications that have been accumulated over the last several years. In addition, we aim to address key basic science studies to further emphasize the importance of translational research outcomes driving clinical management.

Applying JIT principles to resident education to reduce patient delays: a pilot study in an academic medical center pain clinic.

OBJECTIVES: This study investigated the effect on patient waiting times, patient/doctor contact times, flow times, and session completion times of having medical trainees and attending physicians review cases before the clinic session. The major hypothesis was that review of cases prior to clinic hours would reduce waiting times, flow times, and use of overtime, without reducing patient/doctor contact time. DESIGN: Prospective quality improvement. SETTING: Specialty pain clinic within Johns Hopkins Outpatient Center, Baltimore, MD, United States. PARTICIPANTS: Two attending physicians participated in the intervention. Processing times for 504 patient visits are involved over a total of 4 months. INTERVENTION: Trainees were assigned to cases the day before the patient visit. Trainees reviewed each case and discussed it with attending physicians before each clinic session. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary measures were activity times before and after the intervention. These were compared and also used as inputs to a discrete event simulation to eliminate differences in the arrival process as a confounding factor. RESULTS: The average time that attending physicians spent teaching trainees while the patient waited was reduced, but patient/doctor contact time was not significantly affected. These changes reduced patient waiting times, flow times, and clinic session times. CONCLUSIONS: Moving some educational activities ahead of clinic time improves patient flows through the clinic and decreases congestion without reducing the times that trainees or patients interact with physicians.

Dynamic Pain Phenotypes are Associated with Spinal Cord Stimulation-Induced Reduction in Pain: A Repeated Measures Observational Pilot Study.

OBJECTIVE: Spinal cord stimulation (SCS) has become a widely used treatment option for a variety of pain conditions. Substantial variability exists in the degree of benefit obtained from SCS and patient selection is a topic of expanding interest and importance. However, few studies have examined the potential benefits of dynamic quantitative sensory testing (QST) to develop objective measures of SCS outcomes or as a predictive tool to help patient selection. Psychological characteristics have been shown to play an important role in shaping individual differences in the pain experience and may aid in predicting responses to SCS. Static laboratory pain-induction measures have also been examined in their capacity for predicting SCS outcomes. METHODS: The current study evaluated clinical, psychological and laboratory pain measures at baseline, during trial SCS lead placement, as well as 1 month and 3 months following permanent SCS implantation in chronic pain patients who received SCS treatment. Several QST measures were conducted, with specific focus on examination of dynamic models (central sensitization and conditioned pain modulation [CPM]) and their association with pain outcomes 3 months post SCS implantation. RESULTS: Results suggest few changes in QST over time. However, central sensitization and CPM at baseline were significantly associated with clinical pain at 3 months following SCS implantation, controlling for psycho/behavioral factors and pain at baseline. Specifically, enhanced central sensitization and reduced CPM were associated with less self-reported pain 3 months following SCS implantation. CONCLUSIONS: These findings suggest a potentially important role for dynamic pain assessment in individuals undergoing SCS, and hint at potential mechanisms through which SCS may impart its benefit.

Review of the Uses of Vagal Nerve Stimulation in Chronic Pain Management.

Recent human and animal studies provide growing evidence that vagal nerve stimulation (VNS) can deliver strong analgesic effects in addition to providing therapeutic efficacy in the treatment of refractory epilepsy and depression. Analgesia is potentially mediated by vagal afferents that inhibit spinal nociceptive reflexes and transmission and have strong anti-inflammatory properties. The purpose of this review is to provide pain practitioners with an overview of VNS technology and limitations. It specifically focuses on clinical indications of VNS for various chronic pain syndromes, including fibromyalgia, pelvic pain, and headaches. We also present potential mechanisms for VNS modulation of chronic pain by reviewing both animal and human studies.

Emerging innovation in pain medicines.

The treatment of pain remains a critical, unmet public health challenge. According to the CDC, in 2021, an estimated 20.9% of US adults (51.6 million people) endured chronic pain, and 6.9% (17.1 million people) endured high-impact chronic pain. Additionally, the impact of the social determinants of health on pain treatment are beginning to emerge. Treating pain addresses its control and relief, enhancing patient outcomes and quality of life. However, current treatment options have limitations, creating a significant need for innovative solutions. This raises the role of innovation in identifying new pain medicines. Thus, the clinical development of novel pain medicines is an unmet need to address public health worldwide.

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Adapting and Evaluating a Theory-Driven, Non-Pharmacological Intervention to Self-Manage Pain.

BACKGROUND: The existing literature has limited detail on theory-driven interventions, particularly in pain studies. We adapted Bandura's self-efficacy framework toward a theory-driven, non-pharmacological intervention using auricular point acupressure (APA) and evaluated participants' perceptions of this intervention on their pain self-management. APA is a non-invasive modality based on auricular acupuncture principles. METHODS: We mapped our study intervention components according to Bandura's key sources of self-efficacy (performance accomplishments, vicarious experience, verbal persuasion, and emotional arousal) to facilitate the self-management of pain. Through a qualitative study design, we conducted virtual interviews at one and three months after a 4-week APA intervention among 23 participants using purposive sampling to describe their experiences in managing their pain based on our theory-driven APA intervention. RESULTS: Using thematic analyses, we found four themes: the enhanced self-management of pain, improved pain outcomes, the feasibility of technology, and the sustainability of APA. CONCLUSIONS: Describing how interventions are mapped according to the elements of theoretical frameworks can help to guide intervention development, advance science and knowledge development, and promote the implementation of interventions. As such, using Bandura's self-efficacy theory as a foundation for the APA intervention, APA was found to be feasible and sustainable, improving self-management, pain intensity, and pain-related outcomes. Participants provided recommendations for the further improvement of this theory-driven intervention.

Multicenter, randomized, controlled comparative-effectiveness study comparing virtual reality to sedation and standard local anesthetic for pain and anxiety during epidural steroid injections.

Background: The use of sedation during interventional procedures has continued to rise resulting in increased costs, complications and reduced validity during diagnostic injections, prompting a search for alternatives. Virtual reality (VR) has been shown to reduce pain and anxiety during painful procedures, but no studies have compared it to a control and active comparator for a pain-alleviating procedure. The main objective of this study was to determine whether VR reduces procedure-related pain and other outcomes for epidural steroid injections (ESI). Methods: A randomized controlled trial was conducted in 146 patients undergoing an ESI at 6 hospitals in Thailand and the United States. Patients were allocated to receive immersive VR with local anesthetic, sedation with midazolam and fentanyl plus local anesthetic, or local anesthetic alone. The primary outcome was procedure-related pain recorded on a 0-10 scale. Other immediate-term outcome measures were pain from a standardized subcutaneous skin wheal, procedure-related anxiety, ability to communicate, satisfaction, and time to discharge. Intermediate-term outcome measures at 4 weeks included back and leg pain scores, function, and success defined as a ≥2-point decrease in average leg pain coupled with a score ≥5/7 on a Patient Global Impression of Change scale. Findings: Procedure-related pain scores with both VR (mean 3.7 (SD 2.5)) and sedation (mean 3.2 (SD 3.0)) were lower compared to control (mean 5.2 (SD 3.1); mean differences -1.5 (-2.7, -0.4) and -2.1 (-3.3, -0.9), respectively), but VR and sedation scores did not significantly differ (mean difference 0.5 (-0.6, 1.7)). Among secondary outcomes, communication was decreased in the sedation group (mean 3.7 (SD 0.9)) compared to the VR group (mean 4.1 (SD 0.5); mean difference 0.4 (0.1, 0.6)), but neither VR nor sedation was different than control. The trends favoring sedation and VR over control for procedure-related anxiety and satisfaction were not statistically significant. Post-procedural recovery time was longer for the sedation group compared to both VR and control groups. There were no meaningful intermediate-term differences between groups except that medication reduction was lowest in the control group. Interpretation: VR provides comparable benefit to sedation for procedure-related pain, anxiety and satisfaction, but with fewer side effects, superior communication and a shorter recovery period. Funding: Funded in part by grants from MIRROR, Uniformed Services University of the Health Sciences, U.S. Dept. of Defense, grant # HU00011920011. Equipment was provided by Harvard MedTech, Las Vegas, NV.

Perioperative Management of Antiplatelet and Anticoagulant Therapy in Patients Undergoing Interventional Techniques: 2024 Updated Guidelines from the American Society of Interventional Pain Physicians (ASIPP).

BACKGROUND: The frequency of performance of interventional techniques in chronic pain patients receiving anticoagulant and antiplatelet therapy continues to increase. Understanding the importance of continuing chronic anticoagulant therapy, the need for interventional techniques, and determining the duration and discontinuation or temporary suspension of anticoagulation is crucial to avoiding devastating complications, primarily when neuraxial procedures are performed. Anticoagulants and antiplatelets target the clotting system, increasing the bleeding risk. However, discontinuation of anticoagulant or antiplatelet drugs exposes patients to thrombosis risk, which can lead to significant morbidity and mortality, especially in those with coronary artery or cerebrovascular disease. These guidelines summarize the current peer reviewed literature and develop consensus-based guidelines based on the best evidence synthesis for patients receiving anticoagulant and antiplatelet therapy during interventional procedures. STUDY DESIGN: Review of the literature and development of guidelines based on best evidence synthesis. OBJECTIVES: To provide a current and concise appraisal of the literature regarding the assessment of bleeding and thrombosis risk during interventional techniques for patients taking anticoagulant and/or antiplatelet medications. METHODS: Development of consensus guidelines based on best evidence synthesis included review of the literature on bleeding risks during interventional pain procedures, practice patterns, and perioperative management of anticoagulant and antiplatelet therapy. A multidisciplinary panel of experts developed methodology, risk stratification based on best evidence synthesis, and management of anticoagulant and antiplatelet therapy. It also included risk of cessation of anticoagulant and antiplatelet therapy based on a multitude of factors. Multiple data sources on bleeding risk, practice patterns, risk of thrombosis, and perioperative management of anticoagulant and antiplatelet therapy were identified. The relevant literature was identified through searches of multiple databases from 1966 through 2023. In the development of consensus statements and guidelines, we used a modified Delphi technique, which has been described to minimize bias related to group interactions. Panelists without a primary conflict of interest voted on approving specific guideline statements. Each panelist could suggest edits to the guideline statement wording and could suggest additional qualifying remarks or comments as to the implementation of the guideline in clinical practice to achieve consensus and for inclusion in the final guidelines, each guideline statement required at least 80% agreement among eligible panel members without primary conflict of interest. RESULTS: A total of 34 authors participated in the development of these guidelines. Of these, 29 participated in the voting process. A total of 20 recommendations were developed. Overall, 100% acceptance was obtained for 16 of 20 items. Total items were reduced to 18 with second and third round voting. The final results were 100% acceptance for 16 items (89%). There was disagreement for 2 statements (statements 6 and 7) and recommendations by 3 authors. These remaining 2 items had an acceptance of 94% and 89%. The disagreement and dissent were by Byron J. Schneider, MD, with recommendation that all transforaminals be classified into low risk, whereas Sanjeeva Gupta, MD, desired all transforaminals to be in intermediate risk. The second disagreement was related to Vivekanand A. Manocha, MD, recommending that cervical and thoracic transforaminal to be high risk procedures.Thus, with appropriate literature review, consensus-based statements were developed for the perioperative management of patients receiving anticoagulants and antiplatelets These included the following: estimation of the thromboembolic risk, estimation of bleeding risk, and determination of the timing of restarting of anticoagulant or antiplatelet therapy.Risk stratification was provided classifying the interventional techniques into three categories of low risk, moderate or intermediate risk, and high risk. Further, on multiple occasions in low risk and moderate or intermediate risk categories, recommendations were provided against cessation of anticoagulant or antiplatelet therapy. LIMITATIONS: The continued paucity of literature with discordant recommendations. CONCLUSION: Based on the review of available literature, published clinical guidelines, and recommendations, a multidisciplinary panel of experts presented guidelines in managing interventional techniques in patients on anticoagulant or antiplatelet therapy in the perioperative period. These guidelines provide a comprehensive assessment of classification of risk, appropriate recommendations, and recommendations based on the best available evidence.

Evidence-Based Clinical Practice Guidelines on Regenerative Medicine Treatment for Chronic Pain: A Consensus Report from a Multispecialty Working Group.

Purpose: Injectable biologics have not only been described and developed to treat dermal wounds, cardiovascular disease, and cancer, but have also been reported to treat chronic pain conditions. Despite emerging evidence supporting regenerative medicine therapy for pain, many aspects remain controversial. Methods: The American Society of Pain and Neuroscience (ASPN) identified the educational need for an evidence-based guideline on regenerative medicine therapy for chronic pain. The executive board nominated experts spanning multiple specialties including anesthesiology, physical medicine and rehabilitation, and sports medicine based on expertise, publications, research, and clinical practice. A steering committee selected preliminary questions, which were reviewed and refined. Evidence was appraised using the United States Preventive Services Task Force (USPSTF) criteria for evidence level and degree of recommendation. Using a modified Delphi approach, consensus points were distributed to all collaborators and each collaborator voted on each point. If collaborators provided a decision of "disagree" or "abstain", they were invited to provide a rationale in a non-blinded fashion to the committee chair, who incorporated the respective comments and distributed revised versions to the committee until consensus was achieved. Results: Sixteen questions were selected for guideline development. Questions that were addressed included type of injectable biologics and mechanism, evidence in treating chronic pain indications (eg, tendinopathy, muscular pathology, osteoarthritis, intervertebral disc disease, neuropathic pain), role in surgical augmentation, dosing, comparative efficacy between injectable biologics, peri-procedural practices to optimize therapeutic response and quality of injectate, federal regulations, and complications with mitigating strategies. Conclusion: In well-selected individuals with certain chronic pain indications, use of injectable biologics may provide superior analgesia, functionality, and/or quality of life compared to conventional medical management or placebo. Future high-quality randomized clinical trials are warranted with implementation of minimum reporting standards, standardization of preparation protocols, investigation of dose-response associations, and comparative analysis between different injectable biologics.

Quality-of-life scores in neurogenic thoracic outlet syndrome patients undergoing first rib resection and scalenectomy.

OBJECTIVE: First rib resection and scalenectomy (FRRS) has been shown to improve short-term quality of life (QOL) in the treatment of neurogenic thoracic outlet syndrome (NTOS). Long-term benefits are not well studied but are believed to decrease over time. Our objective was to evaluate long-term NTOS outcomes using validated QOL instruments. METHODS: We identified 162 NTOS patients aged ≥18 years treated by FRRS from 2003 to 2010 after they had not responded to conservative management. The patients were mailed three surveys to assess QOL (Short-Form 12 [SF-12], Brief Pain Inventory [BPI], and Cervical Brachial Symptom Questionnaire [CBSQ]), with five total outcomes measures including the SF-12 Physical Component Score (PCS), SF-12 Mental Component Score (MCS), BPI severity, BPI interference, and CBSQ score. Demographic and clinical data were extracted from patient records. Each FRRS was categorized based on postoperative clinical assessment as successful, failed, or leading to recurrent symptoms. RESULTS: Survey yield was 53.7% (n = 87) with mean follow-up of 44.7 months (range, 12.4-91.9 months). There was no significant difference in QOL scores associated with long-term compared with short-term follow-up. Significantly poorer scores on all instruments were associated with comorbid chronic pain syndromes, opioid use, and unfavorable clinical assessment (P < .05). Significantly poorer scores on select instruments were associated with smoking (BPI both; P < .02), age ≥40 years (SF-12 PCS, BPI interference, CBSQ; P < .03), neck and/or shoulder disease (SF-12 both, BPI both; P < .01), postoperative injections (BPI both, CBSQ; P < .05), and complications (SF-12 PCS, CBSQ; P < .05). A positive preoperative scalene block was not significantly associated with long-term QOL scores. CONCLUSIONS: The QOL after FRRS shows no significant difference with longer follow-up. Clinical assessment reflects patient-reported outcomes and can gauge postoperative improvement. Patient factors, particularly comorbidities and opioid use, are more predictive of long-term QOL than is preoperative scalene block and should also be considered when selecting patients for surgical intervention.

Does pain score in response to a standardized subcutaneous local anesthetic injection predict epidural steroid injection outcomes in patients with lumbosacral radiculopathy? A prospective correlational study.

OBJECTIVE: Epidural steroid injections (ESI) are the most commonly performed pain procedures. Despite numerous studies, controversy continues to surround their effectiveness. The purpose of this study is to determine whether a standard, clinical local anesthetic injection can predict outcomes for ESI. STUDY DESIGN: In this multicenter study, 103 patients received two ESI 2 weeks apart. Prior to their first injection, subjects rated the pain intensity of a standardized subcutaneous (SQ) injection of lidocaine prior to the full dose. Numerical rating scale pain scores were correlated with leg and back pain relief, and functional improvement, through 3-month follow-up. OUTCOME MEASURES: A composite successful outcome was predetermined to be a ≥2-point decrease in leg pain score, coupled with a positive global perceived effect. RESULTS: A small but significant relationship was found between SQ pain score and reduction in leg (r = -0.21, 95% CI -0.38 to -0.04; P = 0.03) and back pain (r = -0.22, 95% CI -0.36 to -0.07; P = 0.03). Subjects with a positive outcome at 1 month had a mean SQ pain score of 2.5 (SD 1.9) vs 4.1 (SD 2.7) in those with a negative outcome (P = 0.04). Subjects with SQ pain scores <4/10 had lower leg and back pain scores than those with pain scores ≥4 at 1-month (mean 3.2, SD 2.6 vs 5.1, SD 2.7 for leg, P < 0.01; mean 3.7, SD 2.6 vs 5.0, SD 3.0 for back, P = 0.02) and 3-month (mean 3.8, SD 2.7 vs 5.2, SD 3.1 for leg, P = 0.01; mean 4.0, SD 2.6 vs 4.9, SD 3.1 for back; P = 0.14) follow-up. CONCLUSIONS: The results of this study found a weak positive correlation between SQ pain scores and treatment results. Further research should consider whether pain perception in conjunction with other variables might prove to be a reliable predictor for ESI and other procedural outcomes.

Complementary and alternative treatments for chronic pelvic pain.

Chronic pelvic pain (CPP) is a significant clinical entity that affects both men and women alike. The etiologies of CPP are multifactorial, and treatments are myriad. Complementary and Alternative Medicine (CAM) refers to non-allopathic health systems, and its use is popular in the United States. In particular, several recent studies have investigated the efficacy of various CAM practices in the treatment of CPP. The authors systematically evaluated recent literature in this area by searching the PubMed database for English-language studies published between January 2007 and August 2012.

The Sigma Enigma: A Narrative Review of Sigma Receptors.

The sigma-1 and sigma-2 receptors were first discovered in the 1960s and were thought to be a form of opioid receptors initially. Over time, more was gradually learned about these receptors, which are actually protein chaperones, and many of their unique or unusual properties can contribute to a range of important new therapeutic applications. These sigma receptors translocate in the body and regulate calcium homeostasis and mitochondrial bioenergetics and they also have neuroprotective effects. The ligands to which these sigma receptors respond are several and dissimilar, including neurosteroids, neuroleptics, and cocaine. There is controversy as to their endogenous ligands. Sigma receptors are also involved in the complex processes of cholesterol homeostasis and protein folding. While previous work on this topic has been limited, research has been conducted in multiple disease states, such as addiction, aging. Alzheimer's disease, cancer, psychiatric disorders, pain and neuropathic pain, Parkinson's disease, and others. There is currently increasing interest in sigma-1 and sigma-2 receptors as they provide potential therapeutic targets for many disease indications.

Scrambler Therapy for Patients With Complex Regional Pain Syndrome: A Case Series.

Complex regional pain syndrome is a chronic debilitating pain disorder that is difficult to manage, in part due to its heterogeneous clinical presentation and lack of clearly defined pathophysiology. Patients usually require a multidisciplinary approach to treatment, which can entail pharmacotherapy, physical therapy, behavioral therapy, and interventional pain procedures, such as sympathetic nerve blocks, spinal cord stimulation, and dorsal root ganglion stimulation. However, many patients continue to experience pain refractory to these multimodal strategies. Scrambler therapy (ST) is a noninvasive method of neuromodulation that is applied through cutaneous electrodes, and can alleviate chronic neuropathic pain by stimulating C-fibers and replacing endogenous pain signals with synthetic non-nociceptive signals. Although the use of ST has been reported for several types of refractory central and peripheral neuropathic pain, there is a paucity of data regarding the use of ST for complex regional pain syndrome. We present two patients with complex regional pain syndrome of the right lower extremity, who each underwent ST and experienced significant pain relief and improvement in function and quality of life.