Peripheral Nerve Stimulation for Pain Management: A Survey of Clinical Practice Patterns.

BACKGROUND: Clinical interest in and utilization of peripheral nerve stimulation (PNS) for treating chronic pain has significantly increased in recent years owing to its potential for providing analgesia and improved function and quality of life in comparison with pharmacologic treatments. However, the relative infancy of PNS-specific systems and limited clinical practice guidance likely contribute to significant variation in PNS utilization patterns. OBJECTIVES: We sought to conduct a survey study to characterize PNS-specific clinical practices and propose the next steps in standardizing key practices for PNS utilization. MATERIALS AND METHODS: A 19-question survey exploring PNS-relevant clinical parameters was disseminated online to pain physicians in practice. Descriptive statistics were used to summarize results. RESULTS: A total of 94 responses were collected. Regarding patient selection, most practitioners would apply PNS to treat nociceptive pain from major joint osteoarthritis (77.7%) and chronic low back pain (64.9%), but not for axial neck pain (50.0%). In contrast, most would apply PNS to treat neuropathic pain from peripheral neuralgia (94.7%), pericranial neuralgia (77.7%), and cancer-related neuropathic pain (64.9%). In treating complex regional pain syndrome, most practitioners would apply PNS before all other forms of neuraxial neuromodulation (>50% for each form). Similarly, for treating nonsurgical low back pain, most would apply PNS before neuraxial neuromodulation (>50% for each form) but not before radiofrequency ablation (19.2%). Most routinely performed nerve blocks before PNS, mainly to confirm anatomical coverage (84.0%), and regarded a 50% to 75% interquartile range as the minimum analgesic benefit required before proceeding with PNS. Regarding nerve target selection for treating complex regional pain syndrome of the wrist/hand or ankle/foot, or knee osteoarthritis, we observed a very wide variance of PNS target locations and discrete nerves. Regarding "minor" adverse events, most reported not changing PNS utilization on encountering skin/soft tissue reactions (85.1%), minor infections (76.6%), or lead migration/loss of efficacy (50.0%). In comparison, most reported reducing PNS utilization on encountering skin erosion (58.5%), major infections (58.5%), or lead fractures (41.5%). CONCLUSIONS: There is significant practice variation regarding the utilization of PNS across numerous key clinical considerations. Future research that explores the reasons driving these differences might help optimize patient selection, target selection, periprocedural management, and ultimately outcomes.

The Polyanalgesic Consensus Conference (PACC)®: Updates on Clinical Pharmacology and Comorbidity Management in Intrathecal Drug Delivery for Cancer Pain.

INTRODUCTION: The International Neuromodulation Society convened a multispecialty group of physicians based on expertise with international representation to establish evidence-based guidance on using intrathecal drug delivery in chronic pain treatment. This Polyanalgesic Consensus Conference (PACC)® project's scope is to provide evidence-based guidance for clinical pharmacology and best practices for intrathecal drug delivery for cancer pain. MATERIALS AND METHODS: Authors were chosen on the basis of their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches using Medline, EMBASE, Cochrane CENTRAL, BioMed Central, Web of Science, Google Scholar, PubMed, Current Contents Connect, Meeting Abstracts, and Scopus from 2017 (when the PACC last published guidelines) to the present. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations were based on the strength of evidence, and when evidence was scant, recommendations were based on expert consensus. RESULTS: The PACC evaluated the published literature and established evidence- and consensus-based expert opinion recommendations to guide best practices in treating cancer pain. Additional guidance will occur as new evidence is developed in future iterations of this process. CONCLUSIONS: The PACC recommends best practices regarding the use of intrathecal drug delivery in cancer pain, with an emphasis on managing the unique disease and patient characteristics encountered in oncology. These evidence- and consensus-based expert opinion recommendations should be used as a guide to assist decision-making when clinically appropriate.

Computed Tomographic Characterization for Basivertebral Nerve Ablation Utilizing a Radiofrequency Multitined Expandable Electrode.

Background: A growing body of clinical evidence has demonstrated that intraosseous minimally invasive basivertebral nerve (BVN) ablation results in significant and durable improvements in vertebrogenic back pain. Thus, it is important to develop, refine and validate new and additional devices to accomplish this procedure. Methods: Using reconstructions of 31 patient computed tomography (CT) scans of the lumbosacral spine (L1-S1), the primary objective was to simulate the intravertebral placement of a novel multitined expandable electrode in bipolar configuration at the targeted ablation site and determine if the proper trajectories could be achieved in order for the device tips to be in the correct position for lesion formation at the BVN plexus. Successful device deployment required that the distance between tips was between 10 mm and 20 mm. Results: The mean distances between device tips ranged from 11.35 mm (L5) to 11.87 mm (L3), and there were no statistically significance differences across the six vertebral levels (F = 0.72, p = 0.61). The percentage of successful intraosseous device placements within the tip distance acceptable range (≥ 10 mm to ≤ 20 mm) was 90% (162 of 180), with no tip-to-tip distances > 20 mm. There was a notable association between decreasing vertebral level and mean degree of angulation between contralateral devices ranging from 50.90° at L1 to 91.51° at S1, and the difference between across the six vertebral levels was significant (F = 89.5, p < 0.01). Conclusion: Feasibility evidence is provided from real world CT imaging data that validates using the multitined electrode for proper intraosseous placement within the vertebral body to effectively ablate the BVN plexus.

Management of Refractory Cancer Pain with Intrathecal Drug Delivery and Spinal Cord Stimulation.

Background: Intrathecal pumps (ITPs) are indicated for refractory cancer pain and decrease systemic opioid requirements. While not yet indicated for cancer pain, spinal cord stimulators (SCSs) are used off-label for cancer pain, with increasing evidence of their efficacy. Materials and Methods: A retrospective chart review was conducted of patients who underwent both ITP and at least SCS trial for cancer pain. Primary outcomes were pain numeric rating scale (NRS) and daily morphine equivalents (MEQs). Results: Seventeen patients were identified. Both ITP and SCS were associated with significant decreases in pain ratings at the 3-month follow-up, but this decrease became nonsignificant subsequently. ITP, but not SCS, was associated with a significant decrease in MEQ. Conclusions: ITP and SCS may both provide efficacy for cancer pain, but the opioid-sparing effects of SCS may be limited. ITP and SCS may potentially be complementary in their ability to provide relief from cancer-related pain.

Effectiveness of Hybrid Form Impulse Therapy (HFIT) Compared to Traditional Transcutaneous Electronic Nerve Stimulation (TENS) in Patients with Chronic Low Back and Knee Pain: A Randomized Controlled Trial.

Purpose: Physical therapy (PT) and conservative care are recommended first-line treatments for musculoskeletal (MSK) pain. While essential to high-quality care, these solutions often do not provide immediate or sufficient pain relief. Traditional transcutaneous electronic nerve stimulation (TENS) devices are often recommended; however, there is mixed evidence behind their effectiveness. A novel approach called hybrid form impulse therapy (HFIT) incorporates a priming pulse with a traditional TENS pulse width and frequency. This randomized controlled trial (RCT) aimed to compare the effectiveness of HFIT versus traditional TENS versus usual care among members of a digital MSK program. Patients and Methods: A three-arm RCT comparing HFIT versus TENS versus usual care was conducted. A total of 325 people with chronic back or knee pain who were members of a digital MSK program consisting of PT-guided exercise therapy, education, and coaching were randomized. Outcomes including pain, function, anxiety, and depression were examined at 1, 2, and 4 weeks (primary endpoint). Engagement was measured through exercise therapy (ET) sessions completed. Unadjusted and adjusted logistic generalized estimating equations were conducted. Results: Adjusted per-protocol results at 4 weeks showed significantly lower odds of achieving pain improvement for both TENS (OR: 0.42, 95% CI: [0.19, 0.92]) and usual care (OR: 0.35, 95% CI: [0.17, 0.72]) groups, compared to HFIT group. Both HFIT and usual care users had significantly higher engagement than the TENS users (p=0.026 and p=0.002, respectively). No adverse events were reported throughout the study. Conclusion: More participants of a digital MSK program who were randomized to the HFIT group experienced meaningful pain improvement at 4 weeks than participants who used TENS and usual care. HFIT can be an effective, non-pharmaceutical solution for relief as a complement to first-line treatments for patients with chronic back and knee pain.

Safety and Efficacy of Surgical Implantation of Intrathecal Drug Delivery Pumps in Patients With Cancer With Refractory Pain.

BACKGROUND AND OBJECTIVES: Pain management in patients with cancer is a critical issue in oncology palliative care as clinicians aim to enhance quality of life and mitigate suffering. Most patients with cancer experience cancer-related pain, and 30%-40% of patients experience intractable pain despite maximal medical therapy. Intrathecal pain pumps (ITPs) have emerged as an option for achieving pain control in patients with cancer. Owing to the potential benefits of ITPs, we sought to study the long-term outcomes of this form of pain management at a cancer center. METHODS: We retrospectively reviewed medical records of all adult patients with cancer who underwent ITP placement at a tertiary comprehensive cancer center between 2013 and 2021. Baseline characteristics, preoperative and postoperative pain control, and postoperative complication rate data were collected. RESULTS: A total of 193 patients were included. We found that the average Numerical Rating Scale (NRS) score decreased significantly by 4.08 points (SD = 2.13, P < .01), from an average NRS of 7.38 (SD = 1.64) to an average NRS of 3.27 (SD = 1.66). Of 185 patients with preoperative and follow-up NRS pain scores, all but 9 experienced a decrease in NRS (95.1%). The median overall survival from time of pump placement was 3.62 months (95% CI: 2.73-4.54). A total of 42 adverse events in 33 patients were reported during the study period. The 1-year cumulative incidence of any complication was 15.6% (95% CI: 10.9%-21.1%) and for severe complication was 5.7% (95% CI: 3.0%-9.7%). Eleven patients required reoperation during the study period, with a 1-year cumulative incidence of 4.2% (95% CI: 2.0%-7.7%). CONCLUSION: Our study demonstrates that ITP implantation for the treatment of cancer-related pain is a safe and effective method of pain palliation with a low complication rate. Future prospective studies are required to determine the optimal timing of ITP implantation.

Case Series of Multicontact Peripheral Nerve Stimulation in the Transversus Abdominis Plane for Chronic Abdominal Wall Pain.

OBJECTIVES: Managing abdominal pain can be difficult. This is due to the nonspecific nature of the pain, the multiple etiologies, and the different mechanisms underlying this type of pain. Abdominal wall pain in particular poses its own challenges. Traditionally, chronic abdominal wall pain has been managed with nonopioid analgesics, and in severe cases, opioid therapy has been considered. For patients with chronic abdominal wall pain refractory to medication management, peripheral nerve blocks and spinal cord stimulation also have been trialed with some success. In this study, we present a case series in patients with chronic abdominal wall pain who were treated with a multicontact peripheral nerve stimulation (PNS) system in the transversus abdominis plane (TAP). MATERIALS AND METHODS: This was a single-center, retrospective case series. Data were included from adults with chronic abdominal wall pain whose symptoms were refractory to standard medical management and who underwent a multicontact PNS system placement in the TAP. RESULTS: Four patients met the inclusion criteria. All four patients underwent a multicontact PNS trial lead placement in the TAP. One patient reported no benefit from the trial. The remaining three patients underwent a permanent multicontact PNS system placement in the TAP. CONCLUSIONS: In patients with chronic abdominal wall pain whose symptoms are refractory to conservative medical management, PNS may be an alternative treatment option. As the use of PNS for chronic abdominal wall pain and other fascial planes continues to develop, additional research is necessary to determine optimal placements and specific stimulation parameters.

Novel Implantation Technique for Thoracoabdominal Peripheral Nerve Stimulation via a Transversus Abdominal Plane Approach for Treatment of Chronic Abdominal Pain.

Background: Chronic abdominal pain (CAP) is a common and challenging to treat condition with a global prevalence of up to 25%. Despite extensive evaluation, approximately 40% of patients with CAP have an unknown diagnosis. Medications may be ineffective, and surgery is rarely indicated. Interventional treatment including sympathetic blocks, sympathetic neurolysis, and transversus abdominal plane (TAP) blocks may be an option, but their efficacy can wane over time. Neuromodulation has emerged as an option for these patients, as there is evidence of success with dorsal column spinal cord and dorsal root ganglion (DRG) stimulation. Peripheral nerve stimulation (PNS) may be an alternative option, particularly in higher risk patients or in patients for whom neuraxial access may be unsafe or too technically challenging. Thoracoabdominal nerve peripheral nerve stimulation via a TAP approach may be more specifically targeted in comparison to dorsal column or DRG stimulation. In this short report, we detail a technique that the authors have successfully used for thoracoabdominal nerve PNS via a TAP approach for management of CAP. Methods: This article describes a novel medial to lateral ultrasound guided thoracoabdominal nerve PNS via a TAP approach technique for lead placement and implantation. Results: A medial to lateral ultrasound guided TAP approach as described to successfully implant percutaneous thoracoabdominal nerve PNS leads for management of CAP. Conclusion: The thoracoabdominal nerve PNS via a TAP approach lead placement technique noted in this report has been used as a means for management of CAP utilizing peripheral neuromodulation. Here, we present a short report detailing a potential technique for PNS utilization for management of CAP. Further studies are needed to validate the safety and efficacy of this therapy modality, although the authors have found it to be a viable management option for patients with medically refractory neuropathic CAP.

Ultrasound-guided fascial plane blocks for post-breast surgery pain syndrome.

INTRODUCTION: Persistent pain following breast surgery is common and may be challenging to treat. In patients refractory to conservative treatments, ultrasound-guided fascial plane blocks of thoracic nerves can be a useful option. RESULTS: This type of neuro blockade technique provides advantages in terms of safety and efficacy that are convenient for physicians managing refractory and complex cases of post-breast surgery syndrome. CONCLUSION: This technical review aims to present an up-to-date summary of the most common ultrasound-guided fascial plane blocks for chronic pain in post-breast surgery patients, provide a detailed technical description of each intervention, and propose preferred injections based on the anatomical location of the pain.

Interventional pain management in cancer patients-a scoping review.

BACKGROUND: Pain is the most prevalent symptom in cancer patients. To improve pain care, World Health Organization (WHO) Pain ladder was introduced in 1986 as a template for choosing pain medications in oncological settings. Since then, advancements in oncological treatments have improved the survival of cancer patients, requiring prolonged analgesia in various treatment stages. Additionally, there have been newer challenges in pain management with opioid epidemic and associated opioid use disorders. This has shifted the focus from WHO Pain Ladder and brought new importance to the rapidly evolving realm of interventional pain modalities for cancer pain management. This article reviews such interventional pain and minimally invasive neurosurgical options for pain management in cancer patients. METHODS: Systemic literature search in PubMed, Cochrane, and Embase. This included review articles, randomized controlled trials, non-randomized clinical trials (RCTs), and case series. RESULTS: A large array of interventional pain modalities are available for oncological pain management. These modalities carry relatively lower risk and provide effective analgesia while reducing concerns related to opioid use disorder. They target various areas in the anatomical and physiological pain pathways and provide more focused options for pain management at various stages of cancer and survivorship. Additionally, with improved sterile techniques, better imaging modalities, and growing technical and clinical expertise, interventional pain modalities offer a safe and often more efficacious method of pain management nowadays. Procedural modalities like intrathecal (IT) pumps, neuromodulation, kyphoplasty, and newer more targeted ablative techniques are now increasingly finding more roles and indications in cancer population. CONCLUSIONS: Interventional pain techniques are rapidly evolving and have become an integral part of cancer pain management. They can provide an additional option for cancer pain management, and can help reduce opioid consumption, and associated opioid side effects. With improvement in imaging modalities, procedural techniques, hardware, and infection control, they have a good safety profile and provide a rapid and efficacious approach for cancer pain management. This review articles aims to provide a basic understanding of various interventional pain modalities, their indications, efficacy, safety data, and associated complications.

Opioids and immune checkpoint inhibitors differentially regulate a common immune network in triple-negative breast cancer.

Background: Opioids are the primary analgesics for cancer pain. Recent clinical evidence suggests opioids may counteract the effect of immune checkpoint inhibition (ICI) immunotherapy, but the mechanism for this interaction is unknown. The following experiments study how opioids and immunotherapy modulate a common RNA expression pathway in triple negative breast cancer (TNBC), a cancer subtype in which immunotherapy is increasingly used. This study identifies a mechanism by which opioids may decrease ICI efficacy, and compares ketamine, a non-opioid analgesic with emerging use in cancer pain, for potential ICI interaction. Methods: Tumor RNA expression and clinicopathologic data from a large cohort with TNBC (N=286) was used to identify RNA expression signatures of disease. Various drug-induced RNA expression profiles were extracted from multimodal RNA expression datasets and analyzed to estimate the RNA expression effects of ICI, opioids, and ketamine on TNBC. Results: We identified a RNA expression network in CD8+ T-cells that was relevant to TNBC pathogenesis and prognosis. Both opioids and anti-PD-L1 ICI regulated RNA expression in this network, suggesting a nexus for opioid-ICI interaction. Morphine and anti-PD-L1 therapy regulated RNA expression in opposing directions. By contrast, there was little overlap between the effect of ketamine and anti-PD-L1 therapy on RNA expression. Conclusions: Opioids and ICI may target a common immune network in TNBC and regulate gene expression in opposing fashion. No available evidence supports a similar interaction between ketamine and ICI.

Pain Education and Knowledge (PEAK) Consensus Guidelines for Neuromodulation: A Proposal for Standardization in Fellowship and Training Programs.

The need to be competent in neuromodulation is and should be a prerequisite prior to completing a fellowship in interventional pain medicine. Unfortunately, many programs lack acceptable candidates for these advanced therapies, and fellows may not receive adequate exposure to neuromodulation procedures. The American Society of Pain and Neuroscience (ASPN) desires to create a consensus of experts to set a minimum standard of competence for neurostimulation procedures, including spinal cord stimulation (SCS), dorsal root ganglion stimulation (DRG-S), and peripheral nerve stimulation (PNS). The executive board of ASPN accepted nominations for colleagues with excellence in the subject matter of neuromodulation and physician education. This diverse group used peer-reviewed literature and, based on grading of evidence and expert opinion, developed critical consensus guides for training that all accredited fellowship programs should adopt. For each consensus point, transparency and recusal were used to eliminate bias, and an author was nominated for evidence grading oversight and bias control. Pain Education and Knowledge (PEAK) Consensus Guidelines for Neuromodulation sets a standard for neuromodulation training in pain fellowship training programs. The consensus panel has determined several recommendations to improve care in the United States for patients undergoing neuromodulation. As neuromodulation training in the United States has evolved dramatically, these therapies have become ubiquitous in pain medicine. Unfortunately, fellowship programs and the Accreditation Council for Graduate Medical Education (ACGME) pain program requirements have not progressed training to match the demands of modern advancements. PEAK sets a new standard for fellowship training and presents thirteen practice areas vital for physician competence in neuromodulation.

Intrathecal Drug Delivery Systems for Cancer Pain Control: Insights on Current Contemporary Practices in the US.

OBJECTIVES: Among patients with cancer with moderate to severe, intractable pain, intrathecal drug delivery using an intrathecal drug delivery system (IDDS) offers effective pain control. In this study, we evaluate the trends of IDDS therapy among patients with cancer, associated comorbidities, complications, and outcomes, using a large representative US administrative inpatient data base. MATERIALS AND METHODS: The Nationwide Inpatient Sample (NIS) data base contains data from 48 states and the District of Columbia. The NIS was used to identify patients with cancer who underwent IDDS implantation between 2016 and 2019. Patients with cancer with intrathecal pumps for the treatment of chronic pain were identified using administrative codes. Baseline demographics, hospital characteristics, type of cancer associated with IDDS implantation, palliative care encounters, hospitalization costs, length of stay, and prevalence of bone pain were evaluated in the study. RESULTS: A total of 22,895 (0.32%) individuals with hospital admission for IDDS surgery were included for analysis among 7.06 million individuals with cancer in the final cohort. The IDDS cohort consisted of patients predominantly in the 65-to-79 years age group (40.49%), female sex (50.42%), and Caucasian ethnicity (75.82%). The top five cancers in patients receiving IDDS were lung (27.15%), colorectal (24.9%), liver (16.44%), bone (8.01%), and liver (7.99%) cancer. In addition, the length of stay was six days (interquartile range [IQR] four-nine days) and the median cost of hospital admission was $29,062 (IQR $19,413-$42,261) in the patients who received an IDDS. These factors were greater than those in patients without IDDS. CONCLUSIONS: A very few patients with cancer received IDDS in the US during the study period. Despite recommendations supporting its use, there are significant racial and socioeconomic disparities in IDDS use.

Cannabinoids as a Potential Alternative to Opioids in the Management of Various Pain Subtypes: Benefits, Limitations, and Risks.

INTRODUCTION: Pain is a global phenomenon encompassing many subtypes that include neuropathic, musculoskeletal, acute postoperative, cancer, and geriatric pain. Traditionally, opioids have been a mainstay pharmacological agent for managing many types of pain. However, opioids have been a subject of controversy with increased addiction, fatality rates, and cost burden on the US healthcare system. Cannabinoids have emerged as a potentially favorable alternative or adjunctive treatment for various types of acute and chronic pain. This narrative review seeks to describe the efficacy, risks, and benefits of cannabinoids as an adjunct or even potential replacement for opioids in the treatment of various subtypes of pain. METHODS: In June of 2022, we performed a comprehensive search across multiple databases for English-language studies related to the use of cannabinoids in the treatment of various types pain: neuropathic pain, musculoskeletal pain, acute postoperative pain, cancer pain, and geriatric pain. Data from meta-analyses, systematic reviews, and randomized control trials (RCTs) were prioritized for reporting. We sought to focus our reported analysis on more recent literature as well as include older relevant studies with particularly notable findings. RESULTS: There is conflicting evidence for the use of cannabinoids in the management of pain. While cannabinoids have shown efficacy in treating specific chronic pain subtypes such as neuropathic pain, fibromyalgia pain, and geriatric pain, they do not show as clear benefit in acute postoperative and the majority of musculoskeletal pain syndromes. Data trends towards cannabinoids having a positive effect in treating cancer pain, but results are not as conclusive. To date, there is a paucity of data comparing cannabinoids directly to opioids for pain relief. Overall, the side effects of cannabinoids appear to be relatively mild. However, there is still potential for addiction, altered brain development, psychiatric comorbidities, and drug-drug interactions. CONCLUSION: Cannabinoids may be effective in specific subtypes of pain, but current evidence and guidelines do not yet support its use as the first-line treatment for any type of acute or chronic pain. Rather, it may be considered a good adjunct or alternative for patients who have failed more typical or conservative measures. Additional studies are needed with standardized forms of cannabinoids, route of delivery, and dosing for greater-powered analysis. Providers must weigh the individualized patient risks, benefits, and concurrent medication list in order to determine whether cannabinoids are appropriate for a patient's pain treatment plan.

A practical access for fluoroscopically-guided percutaneous sacroplasty: Case report.

BACKGROUND: Sacral metastases represent the lowest percentage of invasion to the spine, however, as chemotherapy treatments progress, the cancer survival rate has become higher, and the percentage of sacral metastases has increased. Treatment options for sacrum metastases are surgery, radiotherapy, and minimally invasive techniques such as sacroplasty and radiofrequency ablation. Knowing the repercussions that advancing the needle anteriorly (viscera) or medially (sacral roots) can have during the sacroplasty we are describing a technique to perform c-arm sacroplasty in coaxial vision, to identify the anterior sacral cortical bone that is in the limits of the pelvic viscera as well as the sacral foraminal line. CASE PRESENTATION: In the current report, we present a 75-year-old male patient with prostate cancer metastatic to S1, S2, S3 and iliac, with severe lumbar axial pain VAS 8/10. With a caudal tilt between 35-45 degrees until aligning the sacrum in a coaxial view, a 11-gauge Jamshidi needle is advanced from s3 to s1. The trajectory of the needle during the procedure is corroborated in AP and lateral, S1 is cemented, and the needle is withdrawn to cement S2 and S3. After the sacroplasty with the coaxial access, the patient reported VAS 1-2/10. CONCLUSIONS: It is important to offer an adequate quality of life to patients with sacral fractures, whether associated with cancer or sacral insufficiency fractures (SIF). Sacroplasty, being a recently described technique, can be a very viable option for these patients, that's why it is important to have safe and reliable techniques to complement the approach of this minimally invasive technique.The coaxial access may be a safe and practical way to perform sacroplasty in these patients.

Exceptional Cases of Spinal Cord Stimulation for the Treatment of Refractory Cancer-Related Pain.

OBJECTIVES: Cancer pain has traditionally been managed with opioids, adjuvant medications, and interventions including injections, neural blockade, and intrathecal pump (ITP). Spinal cord stimulation (SCS), although increasingly used for conditions such as failed back surgery syndrome and complex regional pain syndrome, is not currently recommended for cancer pain. However, patients with cancer-related pain have demonstrated benefit with SCS. We sought to better characterize these patients and the benefit of SCS in exceptional cases of refractory pain secondary to progression of disease or evolving treatment-related complications. MATERIALS AND METHODS: This was a single-center, retrospective case series at a tertiary cancer center. Adults ≥18 years old with active cancer and evolving pain secondary to disease progression or treatment, whose symptoms were refractory to systemic opioids, and who underwent SCS trial followed by percutaneous implantation between 2016 and 2021 were included. Descriptive statistics included mean, SD, median, and interquartile range (IQR). RESULTS: Eight patients met the inclusion criteria. The average age at SCS trial was 60.0 (SD: ±11.6) years, and 50% were men. Compared with baseline, the median (IQR) change in pain score by numeric rating scale (NRS) after trial was -3 (2). At an average of 14 days after implant, the median (IQR) change in NRS and daily oral morphine equivalents were -2 (3.5) and -126 mg (1095 mg), respectively. At a median of 63 days after implant, the corresponding values were -3 (0.75) and -96 mg (711 mg). There was no significant change in adjuvant therapies after SCS implantation at follow-up. Six patients were discharged within two days after implantation. Two patients were readmitted for pain control within the follow-up period. CONCLUSIONS: In patients with cancer-related pain, SCS may significantly relieve pain, reduce systemic daily opioid consumption, and potentially decrease hospital length of stay and readmission for pain control. It may be appropriate to consider an SCS trial before ITP in select cases of cancer-related pain.

Controversies in intrathecal drug delivery for cancer pain.

Pain and suffering related to cancer are challenging issues that continue to deserve consideration for treatment optimization. Advances in analgesic management and control of the underlying cancer have improved symptom management, yet many patients still suffer from uncontrolled pain. Intrathecal drug delivery has an established role in the management of refractory cancer pain, but there are significant knowledge gaps in our understanding and application of this therapy. This review addresses several areas of controversy, including the importance of intrathecal catheter tip location, the necessity of an intrathecal trial and the role of intrathecal ziconotide and local anesthetics. In each area, the evidence is discussed, with an emphasis on presenting practical clinical guidance and highlighting deficiencies in our knowledge that are worthy of future investigation.

Ultrasound-Guided Peripheral Nerve Blocks: A Practical Review for Acute Cancer-Related Pain.

PURPOSE OF REVIEW: Ultrasound-guided regional techniques, including catheter-based approaches, are a subset of interventional therapies that have gained interest as an option for managing acute cancer-related pain. The authors sought to review the available published evidence and to discuss practical recommendations for expanding access to such therapies. RECENT FINDINGS: In a MEDLINE/Pubmed search of ultrasound-guided peripheral nerve blocks and peripheral nerve catheters for specific anatomic targets, a total of 28 case reports and case series were identified. Included studies described improved analgesia and reduced opioid requirements with highly variable duration of effect. Current level of evidence remains limited. Pain is a symptom that markedly impacts the quality of life of cancer patients and ultrasound-guided regional techniques are a promising therapeutic option albeit with a limited evidence base. Practical recommendations offered for coordinating access to such therapies in the inpatient, emergency department, and outpatient settings may expand interest and facilitate higher quality research.

Application of the novel Nalu™ Neurostimulation System for peripheral nerve stimulation.

Peripheral nerve stimulation is an established treatment modality for chronic neuropathic pain. Over the last decade, with the advent of innovative devices and delivery platforms, peripheral nerve stimulation has evolved from invasive open surgeries to image-guided, minimally invasive percutaneous procedures. The authors hereby present a novel device, the Nalu™ Neurostimulation System (Nalu Medical, CA, USA), which has established its advantages in providing predictable and reliable peripheral nerve stimulation therapy for chronic neuropathic pain management. This novel device is effective in treating chronic pain conditions such as post-herniorrhaphy pain syndrome, intercostal neuralgia, post-laminectomy syndrome, and complex regional pain syndrome and holds great promise for the treatment of peripheral neuropathic pain.

Chronic nerve pain is a debilitating condition that can affect quality of life and functioning. The Nalu™ Neurostimulation System (Nalu Medical, CA, USA) provides long-term pain relief without medications. There are numerous devices currently available that can be utilized to block pain signals using small wires. This system is unique because the wires placed over affected nerves are powered by an external battery that does not require permanent surgical implantation. Pain after hernia surgery, back surgery, hip surgery and knee surgery, as well as nerve pain can be effectively managed by this system.