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Purpose of Review: Low back pain (LBP) is a prevalent condition that is associated with diminished physical function, poor mental health outcomes, and reduced quality of life. Peripheral nerve stimulation (PNS) is an emerging modality that has been utilized to treat LBP. The primary objective of this systematic review is to appraise the level of evidence on the efficacy of PNS for treatment of LBP. Recent Findings: Twenty-nine articles were included in this systematic review, consisting of 828 total participants utilizing PNS as the primary modality for LBP and 173 participants using PNS as salvage or adjunctive therapy for LBP after SCS placement. Different modalities of PNS therapy were reported across studies, including conventional PNS systems stimulating the lumbar medial branch nerves, peripheral nerve field stimulation (PNFS), and restorative neuromuscular stimulation of the multifidus muscles. All studies consistently reported positive modest to moderate improvement in pain intensity with PNS therapy when comparing baseline pain intensity to each study's respective primary follow-up period. There was a very low GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) quality of evidence supporting this finding. Inconsistency was present in some comparative studies that demonstrated no difference between PNS therapy versus control cohorts (sham or SCS therapy alone), which therefore highlighted the potential for placebo effect. Summary: This systematic review highlights that PNS, PNFS, and neuromuscular stimulation may provide modest to moderate pain relief in patients with LBP, although evidence is currently limited due to risk of bias, clinical and methodological heterogeneity, and inconsistency in data. [ABSTRACT FROM AUTHOR]

Research in movement science aims at unravelling mechanisms and designing methods for restoring and maximizing human functional capacity, and many techniques provide access to neural adjustments (acute changes) or long-term adaptations (chronic changes) underlying changes in movement capabilities. First described by Paul Hoffmann over a century ago, when an electrical stimulus is applied to a peripheral nerve, this causes action potentials in afferent axons, primarily the Ia afferents of the muscle spindles, which recruit homonymous motor neurons, thereby causing an electromyographic response known as the Hoffmann (H) reflex. This technique is a valuable tool in the study of the neuromuscular function in humans and has provided relevant information in the neural control of movement. The large use of the H reflex in motor control research on humans relies in part to its relative simplicity. However, such simplicity masks subtleties that require rigorous experimental protocols and careful data interpretation. After highlighting basic properties and methodological aspects that should be considered for the correct use of the H-reflex technique, this brief narrative review discusses the purpose of the H reflex and emphasizes its use as a tool to assess the effectiveness of Ia afferents in discharging motor neurones. The review also aims to reconsider the link between H-reflex modulation and Ia presynaptic inhibition, the use of the H-reflex technique in motor control studies, and the effects of ageing. These aspects are summarized as recommendations for the use of the H reflex in motor control research on humans. [ABSTRACT FROM AUTHOR]

Introduction: The peripheral nervous system is an increasingly popular target for chronic pain treatment modalities. Noninvasive neuromodulation has shown promise at providing significant chronic pain relief with a much safer side effect profile. This retrospective pilot study is shaped around a noninvasive neuromodulation system over a 2-week treatment timeline. Methods: Open-label survey of chronic pain patients recruited from Veteran Affairs, orthopedic, and pain health systems. If a noninvasive neuromodulation system was prescribed the patients were then offered a 2-week follow-up survey. This voluntary survey did not affect their therapy duration or quality. This survey was designed to address similar metrics as smaller noninvasive neuromodulation studies to allow a quality comparison while giving more power with a large population size of 1511 patients. Overall pain scores (including before and after scores), satisfaction level, desire to continue therapy, medication use, effect on functional metrics (mood, sleep, sit, stand, walk, and lift), and activities of daily living (ADL) scores were assessed. Results: The results demonstrated an overall pain reduction of 46%. All functional metrics were improved throughout with the largest improvements reported in mood and sleep at over 47%. Medication use was reported as decreased or eliminated in 42% of patients. There were no adverse reactions or complications reported over the 1511 patients. Conclusion: This survey is amongst the largest population sizes every studied for noninvasive neuromodulation. Within just 2 weeks patients can see a reduction in overall pain and medication needs. Although survey studies have inherent limitations such as duration and compliance biases with such an overwhelming benefit in every category we believe that noninvasive neuromodulation therapy is a promising, safe, and cost-effective therapy. Future studies should focus on long-term follow-ups and post-therapy pain scores with a placebo group. [ABSTRACT FROM AUTHOR]

Chronic pain is a debilitating condition with a growing prevalence both in the USA and globally. The complex nature of this condition necessitates a multimodal approach to pain management that extends beyond the established pharmaceutical interventions currently employed. A variety of devices comprising both invasive and noninvasive approaches are available to patients, serving as adjuvants to existing regimens. The benefits of these interventions are notable for their lack of addiction potential, potential for patient autonomy regarding self-administration, minimal to no drug interaction, and overall relative safety. However, there remains a need for further research and more robust clinical trials to assess the true efficacy of these interventions and elucidate if there is an underlying physiological mechanism to their benefit in treating chronic pain or if their effect is predominantly placebo in nature. Regardless, the field of device-based intervention and treatment remains an evolving field with much promise for the future chronic pain management. [ABSTRACT FROM AUTHOR]

ObjectiveA novel protocol for paired associative stimulation (PAS), called high PAS, consists of high-intensity transcranial magnetic stimulation (TMS) and high-frequency peripheral nerve stimulation (PNS). High PAS was developed for spinal cord injury rehabilitation and targets plastic changes in stimulated pathways in the corticospinal tract, which improves motor function. As therapy interventions can last many weeks, it is important to fully understand the effects of high PAS, including its effect on the cardiovascular system. Heart rate variability (HRV) has been used to measure changes in both sympathetic and parasympathetic systems.MethodsWe used short-term HRV measurements to evaluate the effects of one 20-min session of high PAS on 17 healthy individuals. HRV was recorded for 5 min before (PRE), during (STIM), immediately after (POST), 30 min after (POST30), and 60 min after (POST60) the stimulation. Five participants repeated the HRV setup with sham stimulation.ResultsA significant decrease in low-frequency (LF) power (n.u.) (p = 0.002), low-frequency to high-frequency (HF) ratio (p = 0.017), in Poincaré plot [the standard deviation of RR intervals perpendicular to (SD1) and along (SD2) the line of identity SD2/SD1 ratio p

Rehabilitation approaches for individuals with neurologic conditions have increasingly shifted toward promoting neuroplasticity for enhanced recovery and restoration of function. This review focuses on exercise strategies and non-invasive neuromodulation techniques that target neuroplasticity, including transcranial magnetic stimulation (TMS), vagus nerve stimulation (VNS), and peripheral nerve stimulation (PNS). We have chosen to focus on non-invasive neuromodulation techniques due to their greater potential for integration into routine clinical practice. We explore and discuss the application of these interventional strategies in four neurological conditions that are frequently encountered in rehabilitation settings: Parkinson’s Disease (PD), Traumatic Brain Injury (TBI), stroke, and Spinal Cord Injury (SCI). Additionally, we discuss the potential benefits of combining non-invasive neuromodulation with rehabilitation, which has shown promise in accelerating recovery. Our review identifies studies that demonstrate enhanced recovery through combined exercise and non-invasive neuromodulation in the selected patient populations. We primarily focus on the motor aspects of rehabilitation, but also briefly address non-motor impacts of these conditions. Additionally, we identify the gaps in current literature and barriers to implementation of combined approaches into clinical practice. We highlight areas needing further research and suggest avenues for future investigation, aiming to enhance the personalization of the unique neuroplastic responses associated with each condition. This review serves as a resource for rehabilitation professionals and researchers seeking a comprehensive understanding of neuroplastic exercise interventions and non-invasive neuromodulation techniques tailored for specific diseases and diagnoses.

Shoulder tendinopathies produce pain and reduce functionality. The aim of this randomized clinical trial was to analyze the effects of Percutaneous electrolysis (PE), Percutaneous peripheral Nerve Stimulation (PNS) and eccentric exercise (EE) on pain (NPRS), strength, electromyographic activity, ultrasound characteristics of the tendon (echogenicity, thickness and hypervascularization) and functionality (DASH and SPADI) in individuals with supraspinatus tendinopathy. Participants (n = 50) were divided into two groups; they received 4 treatment sessions, 1 per week, of PE and PNS (n = 25) or 10 treatment sessions of TENS and US (n = 25). Both groups performed the EE program consisting of 3 sets of 10 repetitions of each of the 3 exercises, twice a day, during the 4 weeks. Follow-up was carried out at 4, 12 and 24 weeks after the start of the intervention. There are statistically significant differences in the analysis between groups (p < 0.001) in the post-treatment and follow-up measurements favorable to the PE+PNS+EE treatment on pain (NPRS), strength, supraspinatus electromyographic amplitude, ultrasound characteristics of the tendon (echogenicity, thickness and hypervascularization) and DASH and SPADI questionnaires. The combined treatment with PE, PNS and EE is an effective option in the clinical management of tendinopathies, with positive results in the short and long term on the variables studied.

ObjectiveTo evaluate the safety and effectiveness of a wrist-worn peripheral nerve stimulation device in patients with essential tremor (ET) in a single in-office session.MethodsThis was a randomized controlled study of 77 ET patients who received either treatment stimulation (N = 40) or sham stimulation (N = 37) on the wrist of the hand with more severe tremor. Tremor was evaluated before and immediately after the end of a single 40-minute stimulation session. The primary endpoint compared spiral drawing in the stimulated hand using the Tremor Research Group Essential Tremor Rating Assessment Scale (TETRAS) Archimedes spiral scores in treatment and sham groups. Additional endpoints included TETRAS upper limb tremor scores, subject-rated tasks from the Bain and Findley activities of daily living (ADL) scale before and after stimulation as well as clinical global impression-improvement (CGI-I) rating after stimulation.ResultsSubjects who received peripheral nerve stimulation did not show significantly larger improvement in the Archimedes spiral task compared to sham but did show significantly greater improvement in upper limb TETRAS tremor scores (p = 0.017) compared to sham. Subject-rated improvements in ADLs were significantly greater with treatment (49% reduction) than with sham (27% reduction; p = 0.001). A greater percentage of ET patients (88%) reported improvement in the stimulation group as compared to the sham group (62%) according to CGI-I ratings (p = 0.019). No significant adverse events were reported; 3% of subjects experienced mild adverse events.ConclusionsPeripheral nerve stimulation in ET may provide a safe, well-tolerated, and effective treatment for transient relief of hand tremor symptoms.

Corey W Hunter,1,2 Timothy R Deer,3 Mark R Jones,4 George Chiang Chien,5 Ryan S D’Souza,6 Timothy Davis,7 Erica R Eldon,2 Michael F Esposito,8 Johnathan H Goree,9 Lissa Hewan-Lowe,2 Jillian A Maloney,10 Anthony J Mazzola,2 John S Michels,4 Annie Layno-Moses,7 Shachi Patel,11 Jeanmarie Tari,1 Jacqueline S Weisbein,12 Krista A Goulding,13 Anikar Chhabra,13 Jeffrey Hassebrock,13 Chris Wie,10 Douglas Beall,14 Dawood Sayed,15 Natalie Strand10 1Ainsworth Institute of Pain Management, New York, NY, USA; 2Department of Rehabilitation & Human Performance, Icahn School of Medicine at Mount Sinai, New York, NY, USA; 3The Spine and Nerve Center of the Virginias, Charleston, WV, USA; 4Interventional Spine and Pain, Dallas, TX, USA; 5County Medical Center, Ventura, CA, USA; 6Department of Anesthesiology, Mayo Clinic, Rochester, MN, USA; 7Source Healthcare, Santa Monica, CA, USA; 8Interventional Spine and Pain Institute, Vero Beach, FL, USA; 9Department of Anesthesiology, University of Arkansas for Medical Sciences, Little Rock, AR, USA; 10Department of Anesthesiology, Division of Pain Medicine, Mayo Clinic, Phoenix, AZ, USA; 11Delmarva Pain and Spine Center, Newark, DE, USA; 12Napa Valley Orthopaedic Medical Group, Napa, CA, USA; 13Department of Orthopedic Surgery, Mayo Clinic, Phoenix, AZ, USA; 14Comprehensive Specialty Care, Oklahoma City, OK, USA; 15Department of Anesthesiology, Division of Pain Medicine, University of Kansas Medical Center, Kansas City, KS, USACorrespondence: Corey W Hunter, Email chunter@ainPain.comAbstract: Knee pain is second only to the back as the most commonly reported area of pain in the human body. With an overall prevalence of 46.2%, its impact on disability, lost productivity, and cost on healthcare cannot be overlooked. Due to the pervasiveness of knee pain in the general population, there are no shortages of treatment options available for addressing the symptoms. Ranging from physical therapy and pharmacologic agents to interventional pain procedures to surgical options, practitioners have a wide array of options to choose from – unfortunately, there is no consensus on which treatments are “better” and when they should be offered in comparison to others. While it is generally accepted that less invasive treatments should be offered before more invasive ones, there is a lack of agreement on the order in which the less invasive are to be presented. In an effort to standardize the treatment of this extremely prevalent pathology, the authors present an all-encompassing set of guidelines on the treatment of knee pain based on an extensive literature search and data grading for each of the available alternative that will allow practitioners the ability to compare and contrast each option.Keywords: knee, knee pain, genicular nerve, ablation, regenerative medicine, platelet-rich plasma, dorsal root ganglion, peripheral nerve stimulation

Chelsey M Hoffmann,1 Ryan S D’Souza,1 Jonathan M Hagedorn2 1Department of Anesthesiology and Perioperative Medicine, Division of Pain Medicine, Mayo Clinic, Rochester, MN, USA; 2Department of Pain Medicine, iSpine Pain Physicians, Maple Grove, MN, USACorrespondence: Chelsey M Hoffmann, Tel +1 507-422-6378, Fax +1 507-266-7732, Email Hoffmann.chelsey@mayo.eduObjective: To describe the team approach of an interventional pain management practice, with particular emphasis on advanced practice providers (APPs), in the selection, education, care, and management of peripheral nerve stimulation (PNS) patients.Materials and Methods: We devised an APP guide to PNS based on an in-depth search of multiple databases for studies on neuromodulation, pain management, and APPs.Results: Of 65 articles captured in the search strategy, three articles were pertinent to the topic of APP involvement in neuromodulation. More specifically, only one of the three publications on neuromodulation discussed APP involvement in PNS. This single publication was from 1995 and focused on electrical stimulation of the trigeminal ganglion using a permanent percutaneously placed electrode.Conclusion: PNS is growing in clinical indication and use for both acute and chronic pain conditions. With the increasing need for APPs in both general and specialty medicine, it is imperative that APPs are well educated on PNS. Here, we have outlined ways in which APPs can optimize the care of PNS patients and how the skillset of the APP in a PNS practice can potentially improve patient outcomes.Keywords: advanced practice provider, peripheral nerve stimulation, interventional pain management, nurse practitioner, physician assistant

Vagus nerve stimulation (VNS) has been recognized as a useful neuromodulation tool to target the central nervous system by electrical stimulation of peripheral nerves. Activation of the nucleus of the solitary tract (NTS) in the brainstem by vagal afferent nerve fibers allows for modulation of various higher order brain regions, including limbic and cerebral cortex structures. Along with neurological and psychiatric indications, clinical and preclinical studies suggest that VNS can improve memory. While the underlying mechanisms to improve memory with VNS involve brain areas, such as the prefrontal cortex and processes including alertness and arousal, here we focus on VNS-induced memory improvements related to the hippocampus, the main area implicated in memory acquisition. In addition, we detail research demonstrating that a targeted approach to VNS can modify memory outcomes and delve into the molecular mechanisms associated with these changes. These findings indicate that a greater understanding of VNS mechanisms while also considering stimulation parameters, administration site, timing in relation to training, and sex-specific factors, may allow for optimal VNS application to enhance memory.

During contact, phasic and tonic responses provide feedback that is used for task performance and perceptual processes. These disparate temporal dynamics are carried in peripheral nerves, and produce overlapping signals in cortex. Using longitudinal intrafascicular electrodes inserted into the median nerve of a nonhuman primate, we delivered composite stimulation consisting of onset and release bursts to capture rapidly adapting responses and sustained stochastic stimulation to capture the ongoing response of slowly adapting receptors. To measure the stimulation's effectiveness in producing natural responses, we monitored the local field potential in somatosensory cortex. We compared the cortical responses to peripheral nerve stimulation and vibrotactile/punctate stimulation of the fingertip, with particular focus on gamma band (30-65 Hz) responses. We found that vibrotactile stimulation produces consistently phase locked gamma throughout the duration of the stimulation. By contrast, punctate stimulation responses were phase locked at the onset and release of stimulation, but activity maintained through the stimulation was not phase locked. Using these responses as guideposts for assessing the response to the peripheral nerve stimulation, we found that constant frequency stimulation produced continual phase locking, whereas composite stimulation produced gamma enhancement throughout the stimulus, phase locked only at the onset and release of the stimulus. We describe this response as an "Appropriate Response in the gamma band" (ARg), a trend seen in other sensory systems. Our demonstration is the first shown for intracortical somatosensory local field potentials. We argue that this stimulation paradigm produces a more biomimetic response in somatosensory cortex and is more likely to produce naturalistic sensations for readily usable neuroprosthetic feedback. [ABSTRACT FROM AUTHOR]

Bioelectronic medicine can treat diseases and disorders in humans by electrically interfacing with peripheral nerves. Multielectrode cuffs can be used for selective stimulation of portions of the nerve, which is advantageous for treatment specificity. The biocompatibility and conformability of cuffs can be improved by reducing the mechanical mismatch between nerve tissue and cuffs, but selective stimulation of nerves has yet to be achieved with soft and stretchable cuff electrodes. Here, this paper reports the development of a soft and stretchable multielectrode cuff (sMEC) for selective nerve stimulation. The device is made of 50 µm thick silicone with embedded gold nanowire conductors, which renders it functional at 50% strain, and provides superior conformability for wrapping nerves. By using different stimulation protocols, high functional selectivity is achieved with the sMEC's eight stimulation electrodes in a porcine sciatic nerve model. Finite element modeling is used to predict the potential distribution within the nerve, which correlate well with the achieved stimulation results. Recent studies are showing that mechanical softness is of outermost importance for reducing foreign body response. It is therefore believed that the soft high‐performance sMEC technology is ideal for future selective peripheral nerve interfaces for bioelectronic medicine. [ABSTRACT FROM AUTHOR]

The use of stimulation of peripheral nerves to test or treat various medical disorders has been prevalent for a long time. Over the last few years, there has been growing evidence for the use of peripheral nerve stimulation (PNS) for treating a myriad of chronic pain conditions such as limb mononeuropathies, nerve entrapments, peripheral nerve injuries, phantom limb pain, complex regional pain syndrome, back pain, and even fibromyalgia. The ease of placement of a minimally invasive electrode via percutaneous approach in the close vicinity of the nerve and the ability to target various nerves have led to its widespread use and compliance. While most of the mechanism behind its role in neuromodulation is largely unknown, the gate control theory proposed by Melzack and Wall in the 1960s has been the mainstay for understanding its mechanism of action. In this review article, the authors performed a literature review to discuss the mechanism of action of PNS and discuss its safety and usefulness in treating chronic pain. The authors also discuss current PNS devices available in the market today. [ABSTRACT FROM AUTHOR]

We describe a case of left foot and ankle complex regional pain syndrome type 1 that necessitated a novel combination of a functioning dorsal root ganglion stimulation and peripheral nerve stimulation. This approach optimized pain relief, functional improvement, and avoided amputation. [ABSTRACT FROM AUTHOR]

Walking and running are based on rapid burst‐like muscle contractions. Burst‐like contractions generate a Gaussian‐shaped force profile, in which neuromuscular determinants have never been assessed. We investigated the neural and contractile determinants of the rate of force development (RFD) in burst‐like isometric knee extensions. Together with maximal voluntary force (MVF), voluntary and electrically evoked (8 stimuli at 300 Hz, octets) forces were measured in the first 50, 100, and 150 ms of burst‐like quadriceps contractions in 24 adults. High‐density surface electromyography (HDsEMG) was adopted to measure the root mean square (RMS) and muscle fiber conduction velocity (MFCV) from the vastus lateralis and medialis. The determinants of voluntary force at 50, 100, and 150 ms were assessed by stepwise multiple regression analysis. Force at 50 ms was explained by RMS (R2 = 0.361); force at 100 ms was explained by octet (R2 = 0.646); force at 150 ms was explained by MVF (R2 = 0.711) and octet (R2 = 0.061). Peak RFD (which occurred at 60 ± 10 ms from contraction onset) was explained by MVF (R2 = 0.518) and by RMS50 (R2 = 0.074). MFCV did not emerge as a determinant of RFD. Muscle excitation was the sole determinant of early RFD (50 ms), while contractile characteristics were more relevant for late RFD (≥100 ms). As peak RFD is mostly determined by MVF, it may not be more informative than MVF itself. Therefore, a time‐locked analysis of RFD provides more insights into the neuromuscular characteristics of explosive contractions. [ABSTRACT FROM AUTHOR]

Purpose of Review Headaches, especially migraines, are one of the most pervasive neurological disorders affecting up to 15.9% of the population. Current methods of migraine treatment include lifestyle changes, pharmacologic, and minimally invasive techniques such as peripheral nerve stimulation (PNS) and pericranial nerve blocks (PNB). Recent Findings PNBs are used to treat and prevent migraines and involves injection of local anesthetics with or without corticosteroids. PNBs include the greater occipital, supraorbital, supratrochlear, lesser occipital, auriculotemporal, sphenopalantine ganglion, and cervical root nerve blocks. Of the PNBs, the most extensively studied is the greater occipital nerve block (GONB) which has been shown to be an efficacious treatment for migraines, trigeminal neuralgia, hemi-crania continua, and post-lumbar puncture, post-concussive, cluster, and cervicogenic headaches but not medication overuse and chronic tension type headaches. Summary In this review, we aim to summarize the recent literature on PNBs and their efficacy in the treatment of migraines including a brief discussion of peripheral nerve stimulation. [ABSTRACT FROM AUTHOR]

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Abstract Background Neuropathic pain (NP) is characterized by abnormal activation of pain conducting pathways and manifests as mechanical allodynia and thermal hypersensitivity. Peripheral nerve stimulation is used for treatment of medically refractory chronic NP and has been shown to reduce neuroinflammation. However, whether sciatic nerve stimulation (SNS) is of therapeutic benefit to NP remains unclear. Moreover, the optimal frequency for SNS is unknown. To address this research gap, we investigated the effect of SNS in an acute NP rodent model. Methods Rats with right L5 nerve root ligation (NRL) or Sham surgery were used. Ipsilateral SNS was performed at 2 Hz, 20 Hz, and 60 Hz frequencies. Behavioral tests were performed to assess pain and thermal hypersensitivity before and after NRL and SNS. Expression of inflammatory proteins in the L5 spinal cord and the immunohistochemical alterations of spinal cord astrocytes and microglia were examined on post-injury day 7 (PID7) following NRL and SNS. The involvement of the descending pain modulatory pathway was also investigated. Results Following NRL, the rats showed a decreased pain threshold and latency on the von Frey and Hargreaves tests. The immunofluorescence results indicated hyperactivation of superficial spinal cord dorsal horn (SCDH) neurons. Both 2-Hz and 20-Hz SNS alleviated pain behavior and hyperactivation of SCDH neurons. On PID7, NRL resulted in elevated expression of spinal cord inflammatory proteins including NF-κB, TNF-α, IL-1β, and IL-6, which was mitigated by 2-Hz and 20-Hz SNS. Furthermore, 2-Hz and 20-Hz SNS suppressed the activation of spinal cord astrocytes and microglia following NRL on PID7. Activity of the descending serotoninergic pain modulation pathway showed an increase early on PID1 following 2-Hz and 20-Hz SNS. Conclusions Our results support that both 2-Hz and 20-Hz SNS can alleviate NP behaviors and hyperactivation of pain conducting pathways. We showed that SNS regulates neuroinflammation and reduces inflammatory protein expression, astrocytic gliosis, and microglia activation. During the early post-injury period, SNS also facilitates the descending pain modulatory pathway. Taken together, these findings support the therapeutic potential of SNS for acute NP.

ABSTRACT The concern about pain management in exotic mammals is increasing. However, only a few studies describe locoregional anesthesia techniques in rabbits. Thus, this report aims to describe the lumbar paravertebral block, guided by peripheral nerve stimulation, in a rabbit undergoing mid-femoral amputation. We received a one-year-old rabbit weighing 1.27kg with a history of non-union of the right femur and osteomyelitis. The animal came to us for high pelvic limb amputation. After premedication with ketamine, midazolam, and morphine, the patient was maintained under general anesthesia in a non-rebreathing circuit under spontaneous ventilation with isoflurane vaporized in 0.6 oxygen. Using a peripheral nerve stimulator, we performed the lumbar paravertebral block, positioning the needle between the L5 and L6 vertebrae and injecting 0.2mL/kg bupivacaine. The patient remained stable throughout the procedure, without the need for analgesic rescue with opioids during surgery and postoperatively. The discharge occurred after 24 hours. The lumbar paravertebral block proved efficient for trans and postoperative analgesia for high pelvic limbic amputation in rabbits.

Ramana Naidu,1 Sean Li,2 Mehul J Desai,3,4 Samir Sheth,5 Nathan D Crosby,6 Joseph W Boggs6 1California Orthopedics & Spine, Larkspur, CA, USA; 2Premier Pain Centers, Shrewsbury, NJ, USA; 3International Spine Pain & Performance Center, Washington, DC, USA; 4George Washington University, School of Medicine and Health Sciences, Washington, DC, USA; 5Sutter Roseville Pain Management, Roseville, CA, USA; 6SPR Therapeutics, Cleveland, OH, USACorrespondence: Ramana Naidu, California Orthopedics & Spine, 2 Bon Air Road #120, Larkspur, CA, 94939, USA, Tel +1 608-695-7266, Email ramonaidu@gmail.comObjective: Conventional neurostimulation typically involves a brief (eg, ≤ 10-day) trial to assess presumed effectiveness prior to permanent implantation. Low trial conversion rates and high explant rates due to inadequate pain relief highlight the need for improved patient identification strategies. The development of a 60-day percutaneous peripheral nerve stimulation (PNS) system enables evaluation of outcomes following an extended temporary treatment period of up to 60 days, that may obviate or validate the need for permanent implant. The present study provides the first real-world evidence regarding patient response throughout a 60-day PNS treatment period.Methods: Anonymized data listings were compiled from patients who underwent implantation of temporary percutaneous leads and opted-in to provide real-world data to the device manufacturer during routine interactions with device representatives throughout the 60-day treatment.Results: Overall, 30% (222/747) of patients were early responders (≥ 50% pain relief throughout treatment). Another 31% (231/747) of patients initially presented as non-responders but surpassed 50% pain relief by the end of treatment. Conversely, 32% (239/747) of patients were non-responders throughout treatment. An additional 7% (55/747) of patients initially presented as responders but fell below 50% relief by the end of the treatment period.Conclusion: An extended, 60-day PNS treatment may help identify delayed responders, providing the opportunity for sustained relief and improving access to effective PNS treatment. Compared to a conventionally short trial of ≤ 10 days, a longer 60-day PNS treatment may also help reduce explant rates by identifying delayed non-responders unlikely to benefit long-term. These scenarios support the importance of an extended 60-day temporary PNS stimulation period to help inform stepwise treatment strategies that may optimize outcomes and cost-effectiveness.Keywords: peripheral nerve stimulation, neuromodulation, 60-day PNS, chronic pain, real-world evidence

Abstract We describe a case of left foot and ankle complex regional pain syndrome type 1 that necessitated a novel combination of a functioning dorsal root ganglion stimulation and peripheral nerve stimulation. This approach optimized pain relief, functional improvement, and avoided amputation.

During contact, phasic and tonic responses provide feedback that is used for task performance and perceptual processes. These disparate temporal dynamics are carried in peripheral nerves, and produce overlapping signals in cortex. Using longitudinal intrafascicular electrodes inserted into the median nerve of a nonhuman primate, we delivered composite stimulation consisting of onset and release bursts to capture rapidly adapting responses and sustained stochastic stimulation to capture the ongoing response of slowly adapting receptors. To measure the stimulation’s effectiveness in producing natural responses, we monitored the local field potential in somatosensory cortex. We compared the cortical responses to peripheral nerve stimulation and vibrotactile/punctate stimulation of the fingertip, with particular focus on gamma band (30–65 Hz) responses. We found that vibrotactile stimulation produces consistently phase locked gamma throughout the duration of the stimulation. By contrast, punctate stimulation responses were phase locked at the onset and release of stimulation, but activity maintained through the stimulation was not phase locked. Using these responses as guideposts for assessing the response to the peripheral nerve stimulation, we found that constant frequency stimulation produced continual phase locking, whereas composite stimulation produced gamma enhancement throughout the stimulus, phase locked only at the onset and release of the stimulus. We describe this response as an “Appropriate Response in the gamma band” (ARγ), a trend seen in other sensory systems. Our demonstration is the first shown for intracortical somatosensory local field potentials. We argue that this stimulation paradigm produces a more biomimetic response in somatosensory cortex and is more likely to produce naturalistic sensations for readily usable neuroprosthetic feedback.

Maximizing analgesia is critical following joint arthroplasty because postoperative pain is a major barrier to adequate physical therapy. Continuous peripheral nerve blocks have been the mainstay for acute pain management in this population; however, this and similar techniques are limited by their duration of action. Cryoneurolysis and peripheral nerve stimulation are two methodologies used for decades to treat chronic pain. With the advent of portable ultrasound devices and percutaneous administration equipment, both procedures may now be suitable for treatment of acute pain. This article reviews these two modalities and their application to joint arthroplasty.

Percutaneous peripheral nerve stimulation (PNS) is an FDA-cleared pain treatment. Occasionally, fragments of the lead (MicroLead, SPR Therapeutics, LLC, Cleveland, OH, USA) may be retained following lead removal. Since the lead is metallic, there are associated magnetic resonance imaging (MRI) risks. Therefore, the objective of this investigation was to evaluate MRI-related issues (i.e., magnetic field interactions, heating, and artifacts) for various lead fragments.Testing was conducted using standardized techniques on lead fragments of different lengths (i.e., 50, 75, and 100% of maximum possible fragment length of 12.7 cm) to determine MRI-related problems. Magnetic field interactions (i.e., translational attraction and torque) and artifacts were tested for the longest lead fragment at 3 Tesla. MRI-related heating was evaluated at 1.5 Tesla/64 MHz and 3 Tesla/128 MHz with each lead fragment placed in a gelled-saline filled phantom. Temperatures were recorded on the lead fragments while using relatively high RF power levels. Artifacts were evaluated using T1-weighted, spin echo, and gradient echo (GRE) pulse sequences.The longest lead fragment produced only minor magnetic field interactions. For the lead fragments evaluated, physiologically inconsequential MRI-related heating occurred at 1.5 Tesla/64 MHz while under certain 3 Tesla/128 MHz conditions, excessive temperature elevations may occur. Artifacts extended approximately 7 mm from the lead fragment on the GRE pulse sequence, suggesting that anatomy located at a position greater than this distance may be visualized on MRI.MRI may be performed safely in patients with retained lead fragments at 1.5 Tesla using the specific conditions of this study (i.e., MR Conditional). Due to possible excessive temperature rises at 3 Tesla, performing MRI at that field strength is currently inadvisable.

Rheumatoid arthritis (RA) is a chronic, autoimmune inflammatory disease. Despite therapeutic advances, a significant proportion of RA patients are resistant to pharmacological treatment. Stimulation of the cervical vagus nerve is a promising alternative bioelectric neuromodulation therapeutic approach. However, recent clinical trials show cervical vagus nerve stimulation (VNS) was not effective in a significant proportion of drug resistant RA patients. Here we aim to assess if abdominal vagus nerve stimulation reduces disease severity in a collagen-induced arthritis (CIA) rat model. The abdominal vagus nerve of female Dark Agouti rats was implanted and CIA induced using collagen type II injection. VNS (1.6 mA, 200 ms pulse width, 50 ms interphase gap, 27 Hz frequency) was applied to awake freely moving rats for 3 h/day (days 11-17). At 17 days following the collagen injection, unstimulated CIA rats (n = 8) had significantly worse disease activity index, tumor necrosis factor-alpha (TNF-a) and receptor activator of NFkB ligand (RANKL) levels, synovitis and cartilage damage than normal rats (n = 8, Kruskal-Wallis: P < 0.05). However, stimulated CIA rats (n = 5-6) had significantly decreased inflammatory scores and ankle swelling (Kruskal-Wallis: P < 0.05) compared to unstimulated CIA rats (n = 8). Levels of tumor necrosis factor-alpha (TNF-a) remained at undetectable levels in stimulated CIA rats while levels of receptor activator of NFkB ligand (RANKL) were significantly less in stimulated CIA rats compared to unstimulated CIA rats (P < 0.05). Histopathological score of inflammation and cartilage loss in stimulated CIA rats were no different from that of normal (P > 0.05). In conclusion, abdominal VNS alleviates CIA and could be a promising therapy for patients with RA. [ABSTRACT FROM AUTHOR]

The direct neural stimulation of peripheral or central nervous systems has been shown as an effective tool to treat neurological conditions. The electrical activation of the nervous sensory pathway can be adopted to restore the artificial sense of touch and proprioception in people suffering from sensory‐motor disorders. The modulation of the neural stimulation parameters has a direct effect on the electrically induced sensations, both when targeting the somatosensory cortex and the peripheral somatic nerves. The properties of the artificial sensations perceived, as their location, quality and intensity are strongly dependent on the direct modulation of pulse width, amplitude and frequency of the neural stimulation. Different sensory encoding schemes have been tested in patients showing distinct effects and outcomes according to their impact on the neural activation. Here, I reported the most adopted neural stimulation strategies to artificially encode somatosensation into the peripheral nervous system. The real‐time implementation of these strategies in bionic devices is crucial to exploit the artificial sensory feedback in prosthetics. Thus, neural stimulation becomes a tool to directly communicate with the human nervous system. Given the importance of adding artificial sensory information to neuroprosthetic devices to improve their control and functionality, the choice of an optimal neural stimulation paradigm could increase the impact of prosthetic devices on the quality of life of people with sensorimotor disabilities. [ABSTRACT FROM AUTHOR]

Our objective is to present a brief history of the evolution of peripheral nerve stimulation, the current understanding of peripheral nerve stimulation mechanisms in chronic pain, peripheral nerve stimulation applications in upper extremity chronic pain conditions, and complications of peripheral nerve stimulation. The evolution of peripheral nerve stimulation from the early ages to the current status has been facilitated by discoveries in neurobehavioral mechanisms of pain, advances in technology and percutaneous lead development, and the availability of high-quality portable ultrasound units. Peripheral nerve stimulation application in managing upper extremity pain of amputated limbs, post-stroke shoulder pain, complex regional pain syndrome (CRPS), and median, ulnar, and radial neuropathies are discussed. Finally, we describe complications of peripheral nerve stimulation. The availability of ultrasound-guided peripheral nerve stimulation techniques and superior peripheral nerve stimulation technology have opened up new and minimally invasive treatment options for chronic intractable neuropathic pain of the upper extremity. Additionally, the ability to place peripheral nerve stimulation leads percutaneously without open peripheral nerve surgery expands the pool of implanting physicians, while simultaneously decreasing the risks and complications that are associated with open surgery. [ABSTRACT FROM AUTHOR]

Lower back pain (LBP) is one of the most common presenting complaints in clinical adult medical patients. While most often diagnosed as "nonspecific mechanical" in etiology, several lesser known, rarer causes of LBP exist, some of which can even cause neuropathic pain. One of these infrequent causes, cluneal neuralgia (CN), is associated most often with damage or entrapment of the cluneal nerves, particularly the superior cluneal nerve (SCN) and/or the middle cluneal nerve (MCN). These nerves supply sensation to the posterior lumbar and buttock area. However, the LBP caused by CN is often difficult to recognize because it can mimic radiculopathy or sacroiliac joint (SIJ) pain or lead to symptoms in the legs. This makes CN significantly important for clinicians and surgeons to include in their differential. A thorough history proves beneficial in the diagnostic workup, as many risk factors for CN have been reported in the literature. If a CN diagnosis is made, several effective conservative measures can alleviate patients' pain, such as nerve blocks, peripheral nerve stimulation, or high frequency thermal coagulation. Additionally, surgical treatments, such as CN release or endoscopic decompression, have resulted in fantastic patient outcomes. The purpose of the present investigation is to investigate the existing literature about CN as a cause for LBP, consider its epidemiology, discuss its pathophysiology and risk factors, elucidate its clinical presentation and diagnosis, and examine the various treatment modalities that have been reported across the world. [ABSTRACT FROM AUTHOR]

Computational models of electrical stimulation, block and recording of autonomic nerves enable analysis of mechanisms of action underlying neural responses and design of optimized stimulation parameters. We reviewed advances in computational modeling of autonomic nerve stimulation, block, and recording over the past five years, with a focus on vagus nerve stimulation, including both implanted and less invasive approaches. Few models achieved quantitative validation, but integrated computational pipelines increase the reproducibility, reusability, and accessibility of computational modeling. Model-based optimization enabled design of electrode geometries and stimulation parameters for selective activation (across fiber locations or types). Growing efforts link models of neural activity to downstream physiological responses to represent more directly the therapeutic effects and side effects of stimulation. Thus, computational modeling is an increasingly important tool for analysis and design of bioelectronic therapies., Competing Interests: Declaration of interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Objective: The multicenter, randomized, double-blinded, active-sham controlled trial (high-freQUEncy nerve block for poST amputation pain [QUEST]) was conducted to show the safety and efficacy of a novel, peripherally placed high-frequency nerve block (HFNB) system in treating chronic postamputation pain (PAP) in patients with lower limb amputations. The primary outcomes from QUEST were reported previously. This study presents the long-term, single-cross-over, secondary outcomes of on-demand HFNB treatment for chronic PAP., Materials and Methods: After the three-month randomized period, subjects in the active-sham group were crossed over to receive therapy for 12 months. Subjects self-administered HFNB therapy as needed and reported their pain (numerical rating scale [NRS]; range, 1-10) before and 30 and 120 minutes after each treatment. Pain medication use was reported throughout the study. Pain-days per week and quality of life (QOL) were assessed using the Brief Pain Inventory (BPI). Adverse events (AEs) were recorded for all subjects implanted for 12 months., Results: Of 180 subjects implanted in QUEST, 164 (91%) were included in the cross-over period, and 146 (82%) completed follow-up. By month 12, average NRS pain in the combined cohort was reduced by 2.3 ± 2.2 points (95% CI, 1.7-2.8; p < 0.0001) 30 minutes after treatment and 2.9 ± 2.4 points (95% CI, 2.2-3.6; p < 0.0001) 120 minutes after treatment. Mean pain-days per week were significantly reduced (-3.5 ± 2.7 days; p < 0.001), and subject daily opioid use was reduced by 6.7 ± 29.0 morphine equivalent dose from baseline to month 12 (p = 0.013). Mean BPI-interference scores (QOL) improved by 2.7 ± 2.7 points from baseline (p < 0.001). The incidence of nonserious AEs and serious AEs was 72% (130/180) and 42% (76/180), respectively; serious device-related AEs occurred in 15 of 180 subjects (8%)., Conclusion: Overall, HFNB delivered directly to the damaged peripheral nerve provided sustained, on-demand relief of acute PAP exacerbations, reduced opioid utilization, and improved QOL for patients with lower limb amputations with chronic PAP., Competing Interests: Conflict of Interest Leonardo Kapural reports grants and/or personal fees from Biotronik, Medtronic, Nevro, Presidio, Saluda Medical, Nalu Medical, and Gimer Medical. Erika A. Petersen reports grants and/or personal fees from Biotronik, Medtronic Neuromodulation, Nevro, Presidio Medical, Saluda, and SPR, outside the submitted work. Jason M. Schwalb reports grants from Medtronic, SetPoint, Nevro, MeiraGTX; and salary support for role as codirector of the Michigan Spine Surgery Improvement Collaborative, paid directly to employer from Blue Cross Blue Shield of Michigan, outside the submitted work. Konstantin V. Slavin reports institutional research and education grants from Medtronic, Abbott, Boston Scientific, Neuros, and Stryker; personal and institutional support from Abbott, Biotronik, Integer, Medtronic, Saluda, Stimwave, Synergia, Thermaquil, and WISE; and participation on a Data Safety Monitoring Board for Abbott and Nurami. The remaining authors reported no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objectives: Cancer pain is among the most prevalent and challenging symptoms in cancer care, with up to 95% of patients with late-stage cancer experiencing moderate-to-severe pain. Conventional pharmacologic treatments, including opioids, carry risks, and patients' conditions may be refractory to medical management or have contraindications. Neurostimulation techniques, such as spinal cord stimulation (SCS), dorsal root ganglion stimulation (DRGS), and peripheral nerve stimulation (PNS), have shown promise in treating treatment-induced cancer pain. However, a comprehensive review focusing on these techniques for cancer-induced pain alone is necessary., Materials and Methods: A comprehensive literature review was conducted using Medline, Embase, and Cochrane Library data bases, focusing on studies from 2000 onward. Inclusion criteria included interventional and observational studies reporting on SCS, DRGS, and PNS in cancer-induced pain. Studies addressing treatment-induced pain, systematic reviews, meta-analyses, and non-English studies were excluded. Data were extracted and evaluated using the Grades of Recommendation, Assessment, Development, and Evaluation system., Results: The search yielded 831 references, with 24 studies meeting the inclusion criteria. Sixteen studies focused on SCS, seven on PNS, and two cases on DRGS. SCS showed significant pain reduction, with an average decrease in numeric rating scale (NRS) scores from 8.0 to 2.2 over an average 8.4-month follow-up period. PNS also indicated substantial pain relief, with NRS scores decreasing from 8.29 to 3.04 over an average 5.2-month follow-up period. DRGS, although less studied, showed a reduction in NRS scores from 6.0 to 1.0 over an average 6.0-month follow-up period. SCS was associated with a significant reduction in opioid use, with average reported morphine equivalent daily dose (MEDD) change from 1152.2 mg to 739.7 mg over an average 5.0-month period, whereas PNS and DRGS had limited impact on opioid consumption, with no reported MEDD change., Conclusions: Our scoping review synthesizes evidence on neurostimulation interventions for treating cancer-induced pain. Current evidence suggests that interventions such as SCS, DRGS, and PNS may provide clinically meaningful pain relief in patients with cancer-induced pain. Several studies also reported improvements in functionality and quality of life. However, the level of evidence is limited owing to the lack of prospective comparative studies, clinical and methodologic heterogeneity, and small sample sizes., Competing Interests: Conflict of Interest The authors reported no conflict of interest., (Copyright © 2024 International Neuromodulation Society. Published by Elsevier Inc. All rights reserved.)

Objectives: YouTube is an important source of medical information for various medical topics and procedures. The purpose of the present study is to appraise the quality of medical information available on YouTube on the topic of peripheral nerve stimulation (PNS) for chronic pain., Materials and Methods: A total of 53 videos were appraised by four individuals using three scales for appraisal: 1) the Modified DISCERN scale, 2) the Journal of American Medical Association (JAMA) Benchmark scoring, and 3) the Global Quality Scale. Descriptive characteristics and author type of each video were recorded. The mean scores of these scales among all four reviewers based on author type were calculated. One-way analysis of variance was used to compare mean scores of the three scales among author types, and post hoc pairwise Tukey's honestly significant difference test was used to evaluate for significant differences between mean scores. Furthermore, mean scale scores of videos above and below the total average-view count and total average "thumbs ups" were calculated and compared., Results: Most videos (n = 31, 58.5%) were submitted from private practice. The mean Modified DISCERN and JAMA scores of videos by academic and society authors (M = 3.54 and 2.83, respectively) were significantly higher (p < 0.05) than the mean Modified DISCERN and JAMA scores of videos by private practice authors (M = 2.10 and 2.03, respectively). Interestingly, the mean scale scores of videos with above-average view counts were found to be lower than scores of videos with below-average view counts across all three scoring instruments., Conclusions: YouTube videos on PNS stimulation for chronic pain are low to moderate in quality. Videos from academic sources were higher in quality than were private practice videos. Furthermore, videos with above-average view counts had lower mean scores on all three instruments, suggesting most of the viewership had watched lower-quality video content., Competing Interests: Conflict of Interest The authors report no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Low back pain is a highly prevalent condition with substantial costs. Superior cluneal neuralgia is present in up to 14% of low back pain cases. This etiology of back pain is often overlooked because the symptoms of superior cluneal neuralgia manifest similarly to those of other conditions, such as radiculopathy and sacroiliac joint pain. Peripheral nerve stimulation (PNS) is an emerging pain management modality used to treat various chronic pain conditions. This retrospective study will examine the outcomes of patients who have back pain caused by neuralgia and are treated with the permanent Freedom® PNS System (Curonix LLC) at the superior cluneal nerve., Objectives: The primary objective was to examine the responder rate (proportion of patients who experienced greater than 50% relief) and changes in pain scores after the trial procedure. Secondary objectives included changes in pain scores from at least one month after permanent implantation, adverse event occurrences, changes in function and quality of life, and reductions in medication usage., Setting: This was a retrospective single-site study. All procedures were performed by the same interventional pain physician., Methods: A retrospective chart review was conducted to assess baseline and follow-up parameters. Inclusion criteria consisted of requirements that patients be 18 years or older and have a confirmed superior cluneal neuralgia diagnosis responsible for their pain presentation. Exclusion criteria included the presence of another active implanted device for pain management. The 11-point verbal rating scale (VRS) was used to assess pain scores., Results: Twenty-one patients were included in this study. All 21 responded to the trial procedure with a 77% average reduction in VRS scores. At the follow-up (mean = 11 months), 20 patients reported an average 57% reduction in pain scores with the verbal rating scale. The same proportion of patients reported improved function and quality of life. Five patients reported reduced medication usage, including one who stopped taking pain medication altogether. No complications were reported., Limitations: We were limited to the data available in the patient charts since this was a retrospective study investigating the efficacy and safety of the Freedom® PNS System for patients with refractory chronic back pain., Conclusion: When used to target the superior cluneal nerve, the Curonix Freedom® PNS System is an effective and safe treatment for neuralgia-caused chronic lower back pain resistant to conservative therapy.

Background: Dorsal root ganglion stimulation (DRGS) is an established method for treating persistent and severe pain conditions. However, performing DRGS has significant challenges. Current DRGS systems are expensive, hindering accessibility for many patients and health care systems. Additionally, placing DRGS devices requires specialized training in epidural techniques and lead anchoring methods. Technical and financial requirements also limit the clinical applicability and availability of DRGS., Objectives: This study evaluated the feasibility of a new method for rapidly delivering near- DRG stimulation in human cadavers. The method involves a fluoroscopy-guided transforaminal approach using a fully implantable, injectable electrode, and its associated delivery system., Study Design: A human cadaver feasibility study., Setting: A cadaver laboratory., Methods: In this study, 3 anesthesiologist pain physicians received training on the injectable electrode device and delivery system using spine phantom models. They then applied the device's associated implantation techniques to 2 adult male cadavers. In the first cadaver, a single injectable electrode was placed near the left L2 lumbar DRG. In the second cadaver, injectable electrodes were placed near the left L1 and L2 DRG levels, and a benchmark DRGS device was installed at the left L1 level using fluoroscopic guidance. A careful anatomical dissection was then performed for each implanted device., Results: The stimulating contacts of the injectable electrodes were accurately positioned within one mm of the DRG at the lumbar L1 and L2 levels in both cadavers. The distances of both the injectable lead and benchmark DRGS device at the L1 level were measured as one mm from the posterior aspect of the DRG., Limitations: The findings of this study are based on anatomical examinations of a limited number of human cadavers and may not fully represent living human anatomy., Conclusions: To our knowledge, this feasibility cadaver study is the first of its kind to examine the accuracy and efficiency of a fluoroscopy-guided transforaminal approach to place injectable electrodes near the DRG. These promising results suggest that this method could be a viable alternative to existing DRGS techniques, warranting further investigation into its clinical potential.

Background: Peripheral nerve stimulation (PNS) has been used for over 50 years to treat chronic pain by delivering electrical pulses through small electrodes placed near targeted peripheral nerves those outside the brain and spinal cord. Early PNS systems often required invasive neurosurgical procedures. However, since 2015, the Food and Drug Administration (FDA) approved percutaneously implanted PNS leads and neurostimulators  offering a much less invasive, non-opioid option for managing recalcitrant chronic pain. The following FDA-cleared PNS systems are commercially available in the United States for the management of chronic, intractable pain:•    Freedom® Peripheral Nerve Stimulator (PNS) System (Curonix LLC, 2017) •    StimRouter® Neuromodulation System (Bioness, now Bioventus, 2015)•    SPRINT® PNS System (SPR® Therapeutics, Inc., 2016) •    Nalu™ Neurostimulation System (Nalu Medical Inc., 2019)•    ReActiv8® Implantable Neurostimulation System (Mainstay Medical Limited, 2020) The American Society of Interventional Pain Physicians (ASIPP) has published evidence-based consensus guidelines for the application of PNS systems in managing chronic pain., Objective: The guidelines aim to provide evidence-based recommendations for the utilization of peripheral nerve stimulation (PNS) in the management of moderate to severe chronic pain. These guidelines exclude field stimulation, or sacral nerve stimulation., Methods: A multidisciplinary panel of experts in various medical and pharmaceutical fields, convened by ASIPP, reviewed the evidence, considered patient perspectives, and formulated recommendations for implantable peripheral nerve stimulation in chronic pain management. The methodology included developing key questions with evidence-based statements and recommendations. The grading of evidence and recommendations followed a modified approach described by ASIPP, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) method, and the Agency for Healthcare Research and Quality (AHRQ) strength of recommendations methods. The evidence review includes existing guidelines, systematic reviews, comprehensive reviews, randomized controlled trials (RCTs), and observational studies on the effectiveness and safety of implantable peripheral nerve stimulation in managing chronic pain. The quality of published studies was assessed using appropriate instruments for systematic reviews, RCTs, and observational studies.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 to approve 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 31 authors participated in the development of these guidelines. Of these, 23 participated in the voting process. A total of 8 recommendations were developed. Overall, 100% acceptance was obtained for 8 of 8 items. Thus, with appropriate literature review, consensus-based statements were developed for implantable peripheral nerve stimulation in chronic pain management. In preparation of these guidelines, evidence synthesis included 7 systematic reviews, 8 RCTs, and 9 observational studies covering all PNS treatments. The evidence was developed using GRADE criteria or certainty of evidence, and qualitative synthesis based on the best available evidence. The evidence level and recommendations are as follows: For implantable peripheral nerve stimulation systems following a trial or selective lumbar medial branch stimulation without a trial, the evidence is Level III or fair with moderate certainty.  Evidence Level: Fair; Strength of Recommendation: ModerateFor temporary peripheral nerve stimulation for 60 days, the evidence is Level III or fair, with moderate certainty., Evidence Level: Fair; Strength of Recommendation: ModerateBased on the available evidence, it is our recommendation to expand the existing PNS related local coverage determination (LCD) to include craniofacial pain, phantom limb pain, and nociceptive pain in the lower back as present evidence shows Level III or fair with moderate certainty., Limitations: The primary limitation of these guidelines is the paucity of the available literature., Conclusion: These evidence-based guidelines support the use of implantable peripheral nerve stimulation leads and neurostimulators in patients with moderate to severe chronic pain refractory to two or more conservative treatments. These guidelines aim to optimize patient outcomes and promote health equity through the integration of PNS technology in clinical practice.

Intercostal neuralgia is characterized by neuropathic pain along the distribution of the intercostal nerve, which can cause debilitating pain and interfere with daily activities. The literature is extremely limited in assessing the use of neuromodulation to treat trauma-induced intercostal neuralgia. This case reports a 40-year-old patient who presented with decades of refractory, long-standing thoracic pain. The pain ranged from a four out of 10 to a nine out of 10 on the numeric rating scale (NRS). The patient failed pharmacologic therapy, physical therapy, chiropractic care, injection therapy, transcutaneous electrical nerve stimulation (TENS), and spinal cord stimulation (SCS). The patient underwent a 60-day peripheral nerve stimulation (PNS) trial, which temporarily relieved the pain until it was explanted. The patient subsequently underwent placement of a permanent PNS implant, which provided between 80-100% daily pain relief at a six-month follow-up. At the two-year follow-up, the patient continued to experience sustained pain relief, had weaned from opioid medications, and returned to all desired daily activities. This case suggests that minimally invasive PNS can effectively manage pain for patients with intercostal neuralgia who fail conservative measures. Further, to our knowledge, this two-year follow-up is the longest-reported outcome in the literature for using PNS for intercostal neuralgia after traumatic injury., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Gallacher et al.)

Magnetic fields switching at kilohertz frequencies induce electric fields in the body that can cause peripheral nerve stimulation (PNS). Magnetically induced PNS, i.e. magnetostimulation, has been extensively studied below 10 kHz. It is widely characterized using a hyperbolic strength-duration curve (SDC), where the PNS thresholds monotonically decrease with frequency. The very few studies performed at higher frequencies found significant deviations from the hyperbolic SDC above ~ 25 kHz, however, those measurements are sparse and show large variability. We fill the gap in the data by measuring PNS in the head of 8 volunteers using a solenoidal coil at 16 frequencies between 200 Hz and 88.1 kHz. Contrary to the hyperbolic SDC, PNS thresholds did not decrease monotonically with frequency, but reached a minimum ~ 25 kHz. The thresholds then increased by 39% from 25 kHz to 88.1 kHz on average across subjects. Our measurements can be used for guidance and validation of neurodynamic models and to inform PNS limits of magnetic resonance imaging (MRI) gradient coils and magnetic particle imaging (MPI) systems. The observed deviation of the experimentally measured thresholds from the hyperbolic SDC calls for further study of the underlying biological mechanisms of magnetostimulation beyond 25 kHz., Competing Interests: Competing Interests Statement The author(s) declare no competing interests.

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., Competing Interests: Conflict of Interest Amitabh Gulati reports consulting for Medtronic, AIS HealthCare, Neurovasis, SPR Therapeutics, Tersera Medical, Hinge Health, Nalu Medical, and Bausch Health, outside the submitted work. Ryan S. D’Souza receives investigator-initiated research grant funding paid to his institution from Nevro Corp and Saol Therapeutics. The remaining authors reported no conflict of interest., (Copyright © 2024 International Neuromodulation Society. Published by Elsevier Inc. All rights reserved.)

Objective. To investigate the feasibility of delivering multidimensional feedback using a single channel of peripheral nerve stimulation by complementing intensity percepts with flutter frequency percepts controlled by burst period modulation. Approach. Two dimensions of a distally referred sensation were provided simultaneously: intensity was conveyed by the modulation of the pulse charge rate inside short discrete periods of stimulation referred to as bursts and frequency was conveyed by the modulation of the period between bursts. For this approach to be feasible, intensity percepts must be perceived independently of frequency percepts. Two experiments investigated these interactions. A series of two alternative forced choice tasks (2AFC) were used to investigate burst period modulation's role in intensity discernibility. Magnitude estimation tasks were used to determine any interactions in the gradation between the frequency and intensity percepts. Main results. The 2AFC revealed that burst periods can be individually differentiated as a gradable frequency percept in peripheral nerve stimulation. Participants could correctly rate a perceptual scale of intensity and frequency regardless of the value of the second, but the dependence of frequency differentiability on charge rate indicates that frequency was harder to detect with weaker intensity percepts. The same was not observed in intensity differentiability as the length of burst periods did not significantly alter intensity differentiation. These results suggest multidimensional encoding is a promising approach for increasing information throughput in sensory feedback systems if intensity ranges are selected properly. Significance. This study offers valuable insights into haptic feedback through the peripheral nervous system and demonstrates an encoding approach for neural stimulation that may offer enhanced information transfer in virtual reality applications and sensory-enabled prosthetic systems. This multidimensional encoding strategy for sensory feedback may open new avenues for enriched control capabilities., (Creative Commons Attribution license.)

Introduction: Shoulder surgeries (arthroscopic or open) are usually performed under general anesthesia or combined with regional anesthesia. Post-operative pain following shoulder surgery is usually very severe and hinders early mobility of joints and recovery; which is also a cause of mental stress for the patient. Regional anesthetic techniques are known to provide excellent pain control postoperatively, both at rest and on movement. It allows faster recovery with earlier mobilization of joints. Profound knowledge of neural innervation of the shoulder is very essential to provide successful regional anesthesia for shoulder surgeries., Case Reports: We underwent a case series of 10 patients with multiple comorbidities and were categorized as high-risk patients, posted for shoulder surgeries under regional anesthesia (PNS-guided interscalene brachial plexus block combined with suprascapular nerve block). Five out of ten patients were of the ASA 3 category, with multiple comorbidities. Shoulder surgeries (arthroscopic/open) were planned under regional anesthesia with mild sedation and resulted in better surgeon and patient satisfaction perioperatively., Conclusion: Interscalene nerve block combined with suprascapular nerve block should be considered an alternative approach to general anesthesia for shoulder surgeries. Thus sole regional anesthesia can be considered a novel approach for all types of shoulder surgeries and is significantly safer for ASA Grade III and IV patients., Competing Interests: Conflict of Interest: Nil, (Copyright: © Indian Orthopaedic Research Group.)