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The Executive Council of the International Society of Biomechanics has initiated and overseen the commemorations of the Society's 50th Anniversary in 2023. This included multiple series of lectures at the ninth World Congress of Biomechanics in 2022 and XXIXth Congress of the International Society of Biomechanics in 2023, all linked to special issues of International Society of Biomechanics' affiliated journals. This special issue of the Journal of Applied Biomechanics is dedicated to the biomechanics of the neuromusculoskeletal system. The reader is encouraged to explore this special issue which comprises 6 papers exploring the current state-of the-art, and future directions and roles for neuromusculoskeletal biomechanics. This editorial presents a very brief history of the science of the neuromusculoskeletal system's 4 main components: the central nervous system, musculotendon units, the musculoskeletal system, and joints, and how they biomechanically integrate to enable an understanding of the generation and control of human movement. This also entails a quick exploration of contemporary neuromusculoskeletal biomechanics and its future with new fields of application. [ABSTRACT FROM AUTHOR]

Objective: This pilot study aims to evaluate the combined impact of peripheral nerve mobilization (PNM) and virtual reality (VR) game-based gait training on gait parameters in chronic anterior cerebral artery (ACA) stroke patients. Methods: Eight chronic ACA stroke patients were randomized into experimental (PNM + VR) and control (conventional exercises) groups. Interventions were conducted for 45 min per session, five times a week, over 4 weeks. Gait parameters were measured using the OpenPose-based Markerless Gait Analysis System. Results: Both groups showed significant improvements in post-intervention measurements. The control group exhibited a mean increase in gait speed from 0.46 m/s to 0.62 m/s (p < 0.001), while the intervention group showed improvements from 0.41 m/s to 0.54 m/s (p < 0.001). Between-group analyses revealed significant differences in gait parameters post-intervention (p < 0.05). Conclusion: PNM and VR game-based gait training emerge as effective interventions for enhancing gait parameters in ACA stroke rehabilitation. [ABSTRACT FROM AUTHOR]

Simple Summary: Perineural invasion (PNI) is the infiltration of cancer cells into peripheral nerves and is recognized as potential cancer metastasis. The presence of PNI has been extensively studied as a prognostic factor in head and neck squamous cell carcinoma (HNSCC) recently. The aim of this study was to quantitatively assess the prognostic value of PNI in HNSCC. From the results of the systematic review and meta-analysis, we confirmed that PNI is an independent prognostic factor in HNSCC. Specifically, HNSCC patients with PNI have worse survival, and are more likely to relapse locally, regionally, and distantly compared to those without PNI. We hope that these findings can serve as a basis for consideration of PNI as an indicator for more advanced pathological stages and more intensive clinical management for HNSCC patients. The aim of this study was to conduct a comprehensive review of the predictive significance of PNI in HNSCC survival outcomes. A systematic search was conducted across multiple databases, and all studies published in the last decade were screened (Research Registry ID: reviewregistry1853). The included studies were assessed using the Quality in Prognosis Studies tool. Survival outcome data were extracted, combined, and presented as hazard ratios (HR) with a 95% confidence interval (CI). Totally, 74 studies encompassing 27,559 patients were analyzed and revealed a cumulative occurrent rate of 30% for PNI in HNSCC. PNI+ HNSCC patients had a worse overall survival (HR: 1.91, 95% CI: 1.71–2.13), disease-specific survival (HR: 1.79, 95% CI: 1.55–2.07), disease-free survival (HR: 1.82, 95% CI: 1.69–1.96), local recurrence (HR: 2.54, 95% CI: 1.93–3.33), locoregional recurrence (HR: 2.27, 95% CI: 1.82–2.82), locoregional relapse free survival (HR: 1.77, 95% CI: 1.28–2.45), distant metastasis (HR: 1.82, 95% CI: 1.34–2.48), and distant metastasis-free survival (HR: 2.97, 95% CI: 1.82–4.85) compared to those PNI– patients. The available evidence unequivocally establishes PNI as a critical prognostic factor for worse survival in HNSCC patients. [ABSTRACT FROM AUTHOR]

Physiological measures are often used to assess the mental state of human operators in supervisory process control tasks. However, the diversity of research approaches creates a heterogeneous landscape of empirical evidence. To map existing evidence and provide guidance to researchers and practitioners, this paper systematically reviews 109 empirical studies that report relationships between peripheral nervous system measures and mental state dimensions (e.g. mental workload, mental fatigue, stress, and vigilance) of interest. Ocular and electrocardiac measures were the most prominent measures across application fields. Most studies sought to validate such measures for reliable assessments of cognitive task demands and time on task, with measures of pupil size receiving the most empirical support. In comparison, less research examined the utility of physiological measures in predicting human task performance. This approach is discussed as an opportunity to focus on operators' individual response to cognitive task demands and to advance the state of research. Physiological measures can provide the basis for dynamic operator assistance in supervisory process control tasks. This review synthesises the existing evidence, highlighting both the aggregated empirical support and the heterogeneity of the results. To advance the status quo, a larger emphasis on physiological measures as predictors of operator performance is needed. Abbreviations: HF/E: Human factors and ergonomics; CNS: Central nervous system; PNS: Peripheral nervous system; HR: Heart rate; HRV: Heart rate variability; IBI: Interbeat interval; AVNN: Average of RR intervals; SDRR: Standard deviation of RR intervals; CVRR: Coefficient of variation in RR intervals; RMSSD: Root mean square of successive; pNNX: Percentage of successive RR intervals; MAD: Median absolute deviation; LF: Power of the low-frequency; MF: Power of the mid-frequency; HF: Power of the high-frequency; TP: Total power. [ABSTRACT FROM AUTHOR]

Acupuncture, a therapeutic treatment defined as the insertion of needles into the body at specific points (ie, acupoints), has growing in popularity world-wide to treat various diseases effectively, especially acute and chronic pain. In parallel, interest in the physiological mechanisms underlying acupuncture analgesia, particularly the neural mechanisms have been increasing. Over the past decades, our understanding of how the central nervous system and peripheral nervous system process signals induced by acupuncture has developed rapidly by using electrophysiological methods. However, with the development of neuroscience, electrophysiology is being challenged by calcium imaging in view field, neuron population and visualization in vivo. Owing to the outstanding spatial resolution, the novel imaging approaches provide opportunities to enrich our knowledge about the neurophysiological mechanisms of acupuncture analgesia at subcellular, cellular, and circuit levels in combination with new labeling, genetic and circuit tracing techniques. Therefore, this review will introduce the principle and the method of calcium imaging applied to acupuncture research. We will also review the current findings in pain research using calcium imaging from in vitro to in vivo experiments and discuss the potential methodological considerations in studying acupuncture analgesia. [ABSTRACT FROM AUTHOR]

Objective: The diagnosis of acute inflammatory demyelinating polyradiculoneuropathy (AIDP) is based mainly on motor nerve conduction studies (NCSs), which may lead to inconclusive results, especially early in the course of the disease. The present study aimed to evaluate sensory NCSs as an additional tool to aid the identification of this illness. Materials and Methods: We retrospectively evaluated the sensory and motor nerve conduction findings of patients with AIDP and compared them with laboratory controls. The sensitivity and specificity of the NCS parameters and sural sparing pattern (SSP) were also assessed. The NCS patterns were categorized as normal, abnormal, and no response. The association of sensory nerve action potential (SNAP) amplitude patterns and effect of the timing of the electrodiagnostic examination on sensory and motor NCS patterns were analyzed. Results: The most sensitive sensory nerve conduction findings were reduced ulnar (79.3%) and median (75.9%) SNAP amplitudes, which were more sensitive than the compound muscle action potential amplitudes and forearm motor nerve conduction velocities of these nerves. Employing ulnar SNAP for SSP identification was more useful than using the median SNAP. The timing of the electrodiagnostic studies did not affect the patterns of the sensory nerve conduction parameters. Conclusion: The reduction in the median and ulnar SNAP amplitudes along with SSP, with the ulnar SNAP amplitude used for comparison, is beneficial for diagnosing AIDP regardless of the timing of the electrodiagnostic examination. [ABSTRACT FROM AUTHOR]

Background/Aim: Hashimoto thyroiditis (HT) is a common autoimmune thyroid disease that may have systemic effects on any organ, including the inner ear. Increased frequency of autoimmune thyroid disease in patients with Meniere's disease and benign paroxysmal positional vertigo (BPPV) has been found, and autoimmunity was implicated in the etiopathogenesis of both diseases. The aim of this study was to evaluate vestibular functions and the effect of levothyroxine (LT4) therapy in patients with Hashimoto's thyroiditis. Methods: The study included 61 men and women with HT diagnosis (group I: 31 patients who did not receive treatment; group II: 31 patients on LT4 treatment) and 30 healthy individuals (control group) between 18 and 60 years of age. Free T3, free T4, TSH, anti-TPO, and anti-Tg levels of all individuals were measured, and Cervical vestibular evoked myogenic potentials (cVEMPs), ocular vestibular evoked potentials (oVEMP), and video head impulse test (vHIT)tests were performed. Results: In the cVEMP results, a 20% VEMP wave was not obtained in the group with HT on LT4 treatment. However, no significant difference was found in the statistical results between the groups. There was no significant difference in vHIT and oVEMP tests between groups. Vestibular tests of patients with hypothyroidism (TSH >4.9) were compared with those of euthyroid patients. The altered frequency in the cervical VEMP test of the left ear was higher in hypothyroid patients (P=0.042). The oVEMP test results were similar for both ears in both groups. The groups were similar in terms of VOR gain in the vHIT test. Conclusion: In euthyroid HT patients, vestibular tests were normal. Progression of vestibular dysfunction might be induced by hypothyroidism rather than autoimmune thyroid diseases. [ABSTRACT FROM AUTHOR]

BACKGROUND: Outcomes of targeted muscle reinnervation (TMR) and regenerative peripheral nerve interface (RPNI) in the oncologic population are limited. We sought to examine the safety and effectiveness of TMR and RPNI in controlling postamputation pain in the oncologic population. STUDY DESIGN: A retrospective cohort study of consecutive patients who underwent oncologic amputation followed by immediate TMR or RPNI was conducted from November 2018 to May 2022. The primary study outcome was postamputation pain, assessed using the Numeric Pain Scale and Patient-Reported Outcomes Measurement Information System (PROMIS) for residual limb pain (RLP) and phantom limb pain (PLP). Secondary outcomes included postoperative complications, tumor recurrence, and opioid use. RESULTS: Sixty-three patients were evaluated for a mean follow-up period of 11.3 months. The majority of patients (65.1%) had a history of previous limb salvage. At final follow-up, patients had an average Numeric Pain Scale score for RLP of 1.3 ± 2.2 and for PLP, 1.9 ± 2.6. The final average raw PROMIS measures were pain intensity 6.2 ± 2.9 (T-score 43.5), pain interference 14.6 ± 8.3 (T-score 55.0), and pain behavior 39.0 ± 22.1 (T-score 53.4). Patient opioid use decreased from 85.7% preoperatively to 37.7% postoperatively and morphine milligram equivalents decreased from a mean of 52.4 ± 53.0 preoperatively to 20.2 ± 38.4 postopera-tively. CONCLUSIONS: In the oncologic population TMR and RPNI are safe surgical techniques associated with significant reductions in RLP, PLP, and improvements in patient-reported outcomes. This study provides evidence for the routine incorporation of TMR and RPNI in the multidisciplinary care of oncologic amputees. [ABSTRACT FROM AUTHOR]

Background and Aims: Several widely used medications, with a relevant efficacy profile, are toxic to the peripheral nervous system and an even larger number of agents are suspected to be neurotoxic. There are concerns about the use of these drugs in patients with Charcot–Marie–Tooth disease (CMT), a hereditary motor and sensory neuropathy. This review provides evidence‐based updated recommendations on this clinically relevant topic. Methods: A systematic review of the available studies/reports written in English was performed from July to September 2022 including in the search string all reported putative neurotoxic drugs. Results: The results of our systematic review provide evidence‐based support for the statement that use of vincristine, and possibly paclitaxel, can occasionally induce an atypical, and more severe, course of drug‐related peripheral neurotoxicity in CMT patients. It is therefore reasonable to recommend caution in the use of these compounds in CMT patients. However, no convincing evidence for a similar recommendation could be found for all other drugs. Interpretation: It is important that patients with CMT are not denied effective treatments that may prolong life expectancy for cancer or improve their health status if affected by non‐oncological diseases. Accurate monitoring of peripheral nerve function in CMT patients treated with any neurotoxic agent remains mandatory to detect the earliest signs of neuropathy worsening and atypical clinical courses. Neurologists monitoring CMT patients as part of their normal care package or for natural history studies should keep detailed records of exposures to neurotoxic medications and support reporting of accelerated neuropathy progression if observed. [ABSTRACT FROM AUTHOR]

Data on nerve excursion is crucial to inform clinical assessment and treatment using neurodynamic tests and neural mobilization. To synthesize evidence on peripheral nerves longitudinal and transverse excursion in response to joint movement in both asymptomatic and symptomatic individuals and to determine whether there are significant differences between them. Studies were sought using Pubmed, Physiotherapy Evidence Database (PEDro), Academic Search Complete, Scopus, ScienceDirect, Web of Science, and Scielo. Two reviewers independently screened titles and abstracts, assessed full reports, extracted information on studies' characteristics, and assessed their methodological quality. A qualitative synthesis of data was performed. Thirty-one articles were included (19 on nerves of the upper limb and 12 on nerves of the lower limb), of which 21 reported on asymptomatic participants only and 10 compared symptomatic and asymptomatic participants. Longitudinal excursion in asymptomatic participants reached up to 50.2 mm and transverse excursion 4.3 mm. Eight (out of 10) studies found significant differences for nerve excursion between symptomatic and asymptomatic participants for diverse clinical conditions. Nerve excursion varies in response to different combinations of joint movement, positioning of adjacent joints, distance to moving joint and nerve, and needs to be considered in neural testing and mobilization. [ABSTRACT FROM AUTHOR]

The article focuses on 33rd annual meeting of the publisher featuring educational seminar related to tissue engineering, symposium on peripheral nerve regeneration, and luncheon seminar on autoimmune nodopathies.

Vitamin D has come up as a pluripotent biochemical modulator of several systemic functions including its wellestablished musculoskeletal effects functioning as well as other key roles in nervous, cardiac, immune, vascular, and endocrinological systems. It undergoes metabolic activation in the skin, liver, and kidneys to exert its systemic actions primarily through Vitamin D receptor-mediated gene expression. In recent times, the involvement of Vitamin D has been documented in the regulation of neurotrophins, neural differentiation, and maturation, and the synthesis of neuromodulators including acetylcholine, dopamine, and gamma-aminobutyric acid. Clinical studies have also highlighted the involvement of Vitamin D in neurological disorders, thereby underscoring its potential in the clinical management of such disorders. Further, research is required to determine the multipronged roles of Vitamin D and its molecular pathways in neurophysiology for the potential prevention and treatment of neurological dysfunction. [ABSTRACT FROM AUTHOR]

The peripheral nervous system of the octopus is among the most complex of any animal. In each arm, hundreds of serial ganglia form a central core of nervous tissue processing sensory input, issuing motor commands, and exchanging information with the central brain. 1 , 2 , 3 , 4 , 5 In addition to the central cord, there are two other types of neural elements: fine intramuscular nerve cords (INCs) 6 , 7 and small sucker ganglia at the base of each sucker. 2 , 6 , 8 , 9 Connections between these different elements and the structural organization of the arm nervous system remain poorly understood, despite decades of interest and a more recent explosion of studies of the cephalopod nervous system. 8 , 10 , 11 , 12 , 13 , 14 , 15 Here, we use serial blockface electron microscopy to reconstruct large volumes of an arm from Octopus bocki at the base and toward the tip, mapping connections between the various neural elements and their relationship to the muscle and skin. We show that the ganglia follow an alternating mirror-image pattern along the arm, where the left or right-sided location of successive suckers determines ganglionic orientation. We also describe previously unrecognized patterns in (1) continuity of oblique connectives between the INCs that encircle the arm; (2) repeatable structures of the major blood vessel branches and nerve connectives within each ganglion; (3) clustering of rare, unusually large neurons within the cell body layers; and (4) division of the cortex into repeating columns. These new findings from the first 3DEM reconstruction of the arm should greatly facilitate future studies of octopus neurobiology, particularly sensori-motor integration and arm control., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Cerebrospinal fluid (CSF) is responsible for maintaining brain homeostasis through nutrient delivery and waste removal for the central nervous system (CNS). Here, we demonstrate extensive CSF flow throughout the peripheral nervous system (PNS) by tracing distribution of multimodal 1.9-nanometer gold nanoparticles, roughly the size of CSF circulating proteins, infused within the lateral cerebral ventricle (a primary site of CSF production). CSF-infused 1.9-nanometer gold transitions from CNS to PNS at root attachment/transition zones and distributes through the perineurium and endoneurium, with ultimate delivery to axoplasm of distal peripheral nerves. Larger 15-nanometer gold fails to transit from CNS to PNS and instead forms "dye-cuffs," as predicted by current dogma of CSF restriction within CNS, identifying size limitations in central to peripheral flow. Intravenous 1.9-nanometer gold is unable to cross the blood-brain/nerve barrier. Our findings suggest that CSF plays a consistent role in maintaining homeostasis throughout the nervous system with implications for CNS and PNS therapy and neural drug delivery.

As the incidence of extensively drug-resistant tuberculosis is increasing, more cases of linezolid-induced peripheral neuropathy are being noted. It is challenging to treat. In this case report, we describe the successful management of this painful neuropathy using a multimodal multidisciplinary approach. [ABSTRACT FROM AUTHOR]

During nervous system development, axons navigate complex environments to reach synaptic targets. Early extending axons must interact with guidance cues in the surrounding tissue, while later extending axons can interact directly with earlier "pioneering" axons, "following" their path. In Caenorhabditis elegans, the AVG neuron pioneers the right axon tract of the ventral nerve cord. We previously found that aex-3,a rab-3 guanine nucleotide exchange factor, is essential for AVG axon navigation in a nid-1 mutant background and that aex-3might be involved in trafficking of UNC-5, a receptor for the guidance cue UNC-6/netrin. Here, we describe a new gene in this pathway: ccd-5,a putative cdk-5 binding partner. ccd-5 mutants exhibit increased navigation defects of AVG pioneer as well as interneuron and motor neuron follower axons in a nid-1 mutant background.We show that ccd-5 acts in a pathway with cdk-5, aex-3,and unc-5.Navigationdefectsof follower interneuron and motoneuron axons correlate with AVG pioneer axon defects. This suggests that ccd-5 mostly affects pioneer axon navigation and that follower axon defects are largely a secondary consequence of pioneer navigation defects. To determine the consequences for nervous system function, we assessed various behavioral and movement parameters. ccd-5 single mutants have no significant movement defects, and nid-1 ccd-5 double mutants are less responsive to mechanosensory stimuli compared with nid-1 single mutants. These surprisingly minor defects indicate either a high tolerance for axon guidance defects within the motor circuit and/or an ability to maintain synaptic connections among commonly misguided axons. [ABSTRACT FROM AUTHOR]

We determined whether sensorimotor peripheral nerve (PN) function was associated with physical activity (PA) in older men. The Osteoporotic Fractures in Men Study Pittsburgh, PA, site (n = 328, age 78.8 ± 4.7 years) conducted PN testing, including: peroneal motor and sural sensory nerve conduction (latencies, amplitudes: CMAP and SNAP for motor and sensory amplitude, respectively), 1.4g/10g monofilament (dorsum of the great toe), and neuropathy symptoms. ANOVA and multivariate linear regression modeled PN associations with PA (Physical Activity Scale for the Elderly [PASE] and SenseWear Armband). After multivariable adjustment, better motor latency was associated with higher PASE scores (160.5 ± 4.8 vs. 135.6 ± 6.7, p < .01). Those without versus with neuropathy symptoms had higher PASE scores (157.6 ± 5.3 vs. 132.9 ± 7.1, p < .01). Better versus worse SNAP was associated with slightly more daily vigorous activity (9.5 ± 0.8 vs. 7.3 ± 0.7, p = .05). Other PN measures were not associated with PA. Certain PN measures were associated with lower PA, suggesting a potential pathway for disability. [ABSTRACT FROM AUTHOR]

Patients with transthyretin amyloid polyneuropathy (ATTR‐PN) show decreased motor and sensory nerve amplitudes and conduction. Electrophysiological changes over time may be sensitive indicators of progression. This analysis from the Transthyretin Amyloidosis Outcomes Survey (THAOS) assessed longitudinal changes in nerve conduction as signals of neurologic disease progression in patients with hereditary ATTR (ATTRv) amyloidosis. Patients with ATTRv in THAOS with recorded nerve conduction values were included (data cut‐off: January 6, 2020); changes in nerve amplitude and velocity over time were assessed. Patients (n = 1389) were 45.0% male; 80.4% were the Val30Met (p.Val50Met) genotype. Mean (SD) age at enrollment was 43.6 (14.5) years; duration of symptoms was 9.3 (6.4) years. Median (10th, 90th percentile) sural nerve amplitude and velocity was 18.0 (4.9, 35.0) μV and 50.7 (41.0, 57.9) m/s; peroneal conduction was 13.0 (4.4, 27.0) μV and 51.0 (41.7, 59.7) m/s, respectively. Median (10th, 90th percentile) percentage change from baseline in sural nerve amplitude was variable, but generally decreased over time from −7.4 (−43.2, 52.4) at year 1 to −14.4 (−76.9, 46.7) at year 8. Percent change from baseline in sural nerve velocity declined similarly: −0.1 (−14.5, 15.3) at year 1 and − 6.4 (−21.3, 10.5) at year 8. The decline was more pronounced in patients with greater disability at baseline. Similar patterns were observed for the peroneal nerve. These data show an association between nerve amplitudes and velocities and disease severity, suggesting progressive deterioration in nerve conduction may be an indicator of ATTRv amyloidosis disease progression. [ABSTRACT FROM AUTHOR]

Stretching is commonly used to increase range of motion and flexibility. Therefore, investigations are usually oriented towards the muscle-tendon unit. Limited evidence exists regarding potential effects of stretching on peripheral nerves which lie within muscles. The objective of this investigation will be to elucidate the responses of peripheral nerves to stretching. A literature search was performed using the following databases: Scopus, NLM Pubmed and ScienceDirect. Studies regarding the effects of stretching protocols on responses of peripheral nerves were retrieved for investigation. The NHLBI tool was used for quality assessment. Outcomes included nerve stiffness, nerve displacement, pain pressure thresholds and resistive torque. A total of 10 studies were considered eligible and were included in this investigation. The quality assessment of the studies revealed an overall "fair to good" methodological quality across the included studies. All studies except for one involved healthy participants. High heterogeneity of stretching protocols was retrieved. As a consequence of stretching, nerve stiffness (-15.6%) and pain pressure thresholds (1.9kg) increased. Nerve displacements on each movement plane for all the considered nerves and nerve deformation were also frequently observed. Peripheral nerve responses to muscle stretching include decreased nerve stiffness and increased pain pressure thresholds. Nerve displacement also frequently occurs. It is still unclear if reduced nerve displacement may lead to clinical outcomes. There is a lack of longitudinal studies regarding peripheral nerve adaptations to stretching. [ABSTRACT FROM AUTHOR]

Background: The proximity of the posterior interosseous nerve (PIN) to the bicipital tuberosity is clinically important in the increasingly popular anterior single-incision technique for distal biceps tendon repair. Maximal forearm supination is recommended during tendon reinsertion from the anterior approach to ensure the maximum protective distance of the PIN from the bicipital tuberosity. Purpose: To compare the location of the PIN on magnetic resonance imaging (MRI) relative to bicortical drill pin instrumentation for suspensory button fixation via the anterior single-incision approach in varying positions of forearm rotation. Study Design: Descriptive laboratory study. Methods: Axial, non–fat suppressed, T1-weighted MRI scans of the elbow were obtained in positions of maximal supination, neutral, and maximal pronation in 13 skeletally mature individuals. Distances were measured from the PIN to (1) the simulated path of an entering guidewire (GWE-PIN) and (2) the cortical starting point of the guidewire on the bicipital tuberosity (CSP-PIN) achievable from the single-incision approach. To radiographically define the location of the nerve relative to constant landmarks, measurements were also made from the PIN to (3) the prominent-most point on the bicipital tuberosity (BTP-PIN) and (4) a perpendicular plane trajectory from the bicipital tuberosity exiting the opposing radial cortex (PPT-PIN). All measurements were subsequently compared between positions of pronation, neutral, and supination. In supination only, BTP-PIN and PPT-PIN measurements were made and compared at 3 sequential axial levels to evaluate the longitudinal course of the nerve relative to the bicipital tuberosity. Results: Of the 13 study participants, mean age was 38.77 years, and mean body mass index was 25.58. Five participants were female, and 5 left and 8 right elbow MRI scans were reviewed. The GWE-PIN was significantly greater in supination (mean ± SD, 16.01 ± 2.9 mm) compared with pronation (13.66 ± 2.5 mm) (P <.005). The mean CSP-PIN was significantly greater in supination (16.20 ± 2.8 mm) compared with pronation (14.18 ± 2.4 mm) (P <.013).The mean PPT-PIN was significantly greater in supination (9.00 ± 3.0 mm) compared with both pronation (1.96 ± 1.2 mm; P <.001) and neutral (4.73 ± 2.6 mm; P <.001). The mean BTP-PIN was 20.54 ± 3.0, 20.81 ± 2.7, and 20.35 ± 2.9 mm in pronation, neutral, and supination, respectively, which did not significantly differ between positions. In supination, the proximal, midportion, and distal measurements of BTP-PIN did not significantly differ. The proximal PPT-PIN distance (9.08 ± 2.9 mm) was significantly greater than midportion PPT-PIN (5.85 ± 2.4 mm; P <.001) and distal BTP-PIN (2.27 ± 1.8 mm; P <.001). Conclusion: This MRI study supports existing evidence that supination protects the PIN from the entering guidewire instrumentation during anterior, single-incision biceps tendon repair using cortical button fixation. The distances between the entering guidewire trajectory and PIN show that guidewire-inflicted injury to the nerve is unlikely during the anterior single-incision approach. Clinical Relevance: When a safe technique is used, PIN injuries during anterior repair are likely the result of aberrant retractor placement, and we recommend against the use of retractors deep to the radial neck. Guidewire placement as close as possible to the anatomic footprint of the biceps tendon is safe from the anterior approach. MRI evaluation confirms that ulnar and proximal guidewire trajectory is the safest technique when using single-incision bicortical suspensory button fixation. [ABSTRACT FROM AUTHOR]

Background: Rebound pain is a common, yet under-recognised acute increase in pain severity after a peripheral nerve block (PNB) has receded, typically manifesting within 24 h after the block was performed. This retrospective cohort study investigated the incidence and factors associated with rebound pain in patients who received a PNB for ambulatory surgery.Methods: Ambulatory surgery patients who received a preoperative PNB between March 2017 and February 2019 were included. Rebound pain was defined as the transition from well-controlled pain (numerical rating scale [NRS] ≤3) while the block is working to severe pain (NRS ≥7) within 24 h of block performance. Patient, surgical, and anaesthetic factors were analysed for association with rebound pain by univariate, multivariable, and machine learning methods.Results: Four hundred and eighty-two (49.6%) of 972 included patients experienced rebound pain as per the definition. Multivariable analysis showed that the factors independently associated with rebound pain were younger age (odds ratio [OR] 0.98; 95% confidence interval [CI] 0.97-0.99), female gender (OR 1.52 [1.15-2.02]), surgery involving bone (OR 1.82 [1.38-2.40]), and absence of perioperative i.v. dexamethasone (OR 1.78 [1.12-2.83]). Despite a high incidence of rebound pain, there were high rates of patient satisfaction (83.2%) and return to daily activities (96.5%).Conclusions: Rebound pain occurred in half of the patients and showed independent associations with age, female gender, bone surgery, and absence of intraoperative use of i.v. dexamethasone. Until further research is available, clinicians should continue to use preventative strategies, especially for patients at higher risk of experiencing rebound pain. [ABSTRACT FROM AUTHOR]

Initially identified in Drosophila, the Hippo signaling pathway regulates how cells respond to their environment by controlling proliferation, migration and differentiation. Many recent studies have focused on characterizing Hippo pathway function and regulation in mammalian cells. Here, we present a brief overview of the major components of the Hippo pathway, as well as their regulation and function. We comprehensively review the studies that have contributed to our understanding of the Hippo pathway in the function of the peripheral nervous system and in peripheral nerve diseases. Finally, we discuss innovative approaches that aim to modulate Hippo pathway components in diseases of the peripheral nervous system. [ABSTRACT FROM AUTHOR]

The foot‐sole cutaneous receptors (section 2), their function in stance control (sway minimisation, exploratory role) (2.1), and the modulation of their effects by gait pattern and intended behaviour (2.2) are reviewed. Experimental manipulations (anaesthesia, temperature) (2.3 and 2.4) have shown that information from foot sole has widespread influence on balance. Foot‐sole stimulation (2.5) appears to be a promising approach for rehabilitation. Proprioceptive information (3) has a pre‐eminent role in balance and gait. Reflex responses to balance perturbations are produced by both leg and foot muscle stretch (3.1) and show complex interactions with skin input at both spinal and supra‐spinal levels (3.2), where sensory feedback is modulated by posture, locomotion and vision. Other muscles, notably of neck and trunk, contribute to kinaesthesia and sense of orientation in space (3.3). The effects of age‐related decline of afferent input are variable under different foot‐contact and visual conditions (3.4). Muscle force diminishes with age and sarcopenia, affecting intrinsic foot muscles relaying relevant feedback (3.5). In neuropathy (4), reduction in cutaneous sensation accompanies the diminished density of viable receptors (4.1). Loss of foot‐sole input goes along with large‐fibre dysfunction in intrinsic foot muscles. Diabetic patients have an elevated risk of falling, and vision and vestibular compensation strategies may be inadequate (4.2). From Charcot‐Marie‐Tooth 1A disease (4.3) we have become aware of the role of spindle group II fibres and of the anatomical feet conditions in balance control. Lastly (5) we touch on the effects of nerve stimulation onto cortical and spinal excitability, which may participate in plasticity processes, and on exercise interventions to reduce the impact of neuropathy. [ABSTRACT FROM AUTHOR]

Purpose: Endothelial dysfunction is an early and integral atherogenic event. Interventions that improve endothelial function also reduce cardiovascular risk. Due largely to the direct hemodynamic effects of repetitive exercise on the artery wall, exercise training has shown to enhance endothelial function. Land walking (LW) and water walking (WW) induce distinct hemodynamic responses, so the comparison of their effects provides an approach to study shear stress effects on endothelial function. We hypothesized that LW and WW training would have different effects on peripheral artery endothelial function. Methods: Fifty-one sedentary, older (age = 61.9 ± 6.6 yr, 23.5% male) individuals were randomized into one of three groups: control (n = 16), or one of two exercise groups consisting of 3 × 50 min supervised and individually tailored walking sessions per week for 24 consecutive weeks, performed either on LW (n = 17) or on WW (n = 18). Brachial artery endothelial function (flow-mediated dilation) and smooth muscle cell function (glyceryl trinitrate administration) were tested in all participants before (week 0) and after (week 24) the intervention. Results: Differences were apparent in flow-mediated dilation change between the LW group (week 0, 5.39% ± 0.71%, to week 24, 7.77% ± 0.78%; P = 0.009) and the control group (week 0, 5.87% ± 0.73%, to week 24, 5.78% ± 0.78%). No differences in artery dilation response were found after glyceryl trinitrate administration (all P > 0.05). Conclusion: This study suggests that 6-month center-based LW may be superior to WW in terms of improvement in arterial endothelial function in older sedentary individuals. [ABSTRACT FROM AUTHOR]

Unique to vertebrates, the neural crest (NC) is an embryonic stem cell population that contributes to a greatly expanding list of derivatives ranging from neurons and glia of the peripheral nervous system, facial cartilage and bone, pigment cells of the skin to secretory cells of the endocrine system. Here, we focus on what is specifically known about establishment and maintenance of NC stemness and ultimate fate commitment mechanisms, which could help explain its exceptionally high stem cell potential that exceeds the "rules set during gastrulation." In fact, recent discoveries have shed light on the existence of NC cells that coexpress commonly accepted pluripotency factors like Nanog, Oct4/PouV, and Klf4. The coexpression of pluripotency factors together with the exceptional array of diverse NC derivatives encouraged us to propose a new term "pleistopotent" (Greek for abundant, a substantial amount) to be used to reflect the uniqueness of the NC as compared to other post‐gastrulation stem cell populations in the vertebrate body, and to differentiate them from multipotent lineage restricted stem cells. We also discuss studies related to the maintenance of NC stemness within the challenging context of being a transient and thus a constantly changing population of stem cells without a permanent niche. The discovery of the stem cell potential of Schwann cell precursors as well as multiple adult NC‐derived stem cell reservoirs during the past decade has greatly increased our understanding of how NC cells contribute to tissues formed after its initial migration stage in young embryos. [ABSTRACT FROM AUTHOR]

Relatively little is known about how peripheral nervous systems (PNSs) contribute to the patterning of behavior in which their role transcends the simple execution of central motor commands or mediation of reflexes. We sought to draw inferences to this end in the aeolid nudibranch Berghia stephanieae, which generates a rapid, dramatic defense behavior, "bristling." This behavior involves the coordinated movement of cerata, dozens of venomous appendages emerging from the animal's mantle. Our investigations revealed that bristling constitutes a stereotyped but non-reflexive two-stage behavior: an initial adduction of proximate cerata to sting the offending stimulus (stage 1) followed by a coordinated radial extension of remaining cerata to create a pincushion-like defensive screen around the animal (stage 2). In decerebrated specimens, stage 1 bristling was preserved, while stage 2 bristling was replaced by slower, uncoordinated ceratal movements. We conclude from these observations that, first, the animal's PNS and central nervous system (CNS) mediate stages 1 and 2 of bristling, respectively; second, the behavior propagates through the body utilizing both peripheral- and central-origin nerve networks that support different signaling kinetics; and third, the former network inhibits the latter in the body region being stimulated. These findings extend our understanding of the PNS' computational capacity and provide insight into a neuroethological scheme in which the CNS and PNS both independently and interactively pattern different aspects of non-reflexive behavior., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Despite the peripheral nervous systems (PNS) capacity to regenerate, functional restoration is highly variable following peripheral nerve injury (PNI), oftentimes leading to persistent functional deficits. In the preclinical arena, advances in the therapeutic use of exogenous neurotrophic factors and synthetic neural scaffold technology hold promise in augmenting endogenous PNS regeneration following PNI. Clinical trials utilizing neurotrophic factors for other indications (eg, peripheral neuropathy) may provide insight into their role in PNI. Here we provide an updated review of progress made toward enhancing regeneration after PNI with a focus on neurotrophic factors and bioengineered scaffolds. [ABSTRACT FROM AUTHOR]

Schwannoma, also known as neurilemmoma, is a tumor of the nerve sheath, which most often occurs in the peripheral nerves of the extremities. Schwannoma can be accompanied by symptoms such as pain, paresthesia, and Tinel sign; however, patients can also be asymptomatic. Here, we present the case of a 17-year-old woman who presented with a slowly growing, asymptomatic, postauricular mass that appeared 10 years prior. Ultrasonography was performed, and the mass was thought to be an epidermal inclusion cyst. However, the clinical manifestation during surgery was not correlated to an epidermal inclusion cyst, leading to the suspicion of schwannoma from the posterior branch of the great auricular nerve. After a meticulous dissection, schwannoma was diagnosed based on a permanent section biopsy. Postoperative complications and recurrence were not observed. Schwannoma in the peripheral nerve area of the face is rare. Therefore, an investigation of tumors that occur where the nerve passes using imaging and clinical features is necessary to confirm the diagnosis of schwannoma and to establish suitable treatment methods. [ABSTRACT FROM AUTHOR]

Two regional analgesic modalities currently cleared by the U.S. Food and Drug Administration hold promise to provide postoperative analgesia free of many of the limitations of both opioids and local anesthetic-based techniques. Cryoneurolysis uses exceptionally low temperature to reversibly ablate a peripheral nerve, resulting in temporary analgesia. Where applicable, it offers a unique option given its extended duration of action measured in weeks to months after a single application. Percutaneous peripheral nerve stimulation involves inserting an insulated lead through a needle to lie adjacent to a peripheral nerve. Analgesia is produced by introducing electrical current with an external pulse generator. It is a unique regional analgesic in that it does not induce sensory, motor, or proprioception deficits and is cleared for up to 60 days of use. However, both modalities have limited validation when applied to acute pain, and randomized, controlled trials are required to define both benefits and risks. [ABSTRACT FROM AUTHOR]

Peripheral nerve injury often requires medical intervention. Unfortunately, many patients never have a full recovery, despite a multi-disciplinary approach, including operative intervention and physical and/or occupational therapy. Outcomes are multifactorial, but are largely affected by the original injury severity, and patient comorbidities. A lcoholism, diabetes mellitus and ageing may detrimentally affect the outcomes of nerve injury; however little is known about tobacco's potential impact on nerve regeneration. Tobacco has known immunomodulatory effects, which suggests that it might affect peripheral nerve regeneration and functional recovery following injury. This review characterizes the effects of tobacco use on the complex cellular and chemokine interactions in peripheral nerve regeneration. [ABSTRACT FROM AUTHOR]

Background: Posterior interosseous nerve (PIN) entrapment syndrome is a rare condition and is predisposed by anatomical factors such as narrow passages through fibrous arcades; whereas, the Arcade of Frohse (AF) is the most common entrapment point. The aim of this study was to evaluate the entrance and exit points of the PIN into the supinator in detail. Materials and Methods: One hundred unpaired upper extremities underwent dissection. The PIN's entrance and exit points from the supinator were depicted. The distances between the tip of the radial head (RH) and the AF and the exit point of the PIN from the supinator were measured. Further, it was checked if the borders of the AF and the exit point were muscular, tendinous or a combination of these. Results: The interval between the PIN's entry into the supinator and the tip of the RH was at a mean of 28.9 mm. Concerning the border of the AF, in 54 cases a muscular and in 46 specimens a tendinous version could be observed. The interval between the exit point of the PIN and the tip of the RH proved to be at a mean of 64.2 mm. Further, the exit's border was muscular in 65 specimens and tendinous in 35 cases. Conclusion: During surgical treatment of the PIN syndrome, it needs to be kept in mind that approximately one-third of all patients might also suffer from entrapment at the exit point of the PIN. [ABSTRACT FROM AUTHOR]

Aim: To examine the associations between continuous overlapping net glycaemic action (CONGA), percentage time in hyperglycaemia (%HG) or normoglycaemia (%NG) and peripheral nerve structure and function in type 1 diabetes. Methods: Twenty‐seven participants with type 1 diabetes underwent continuous glucose monitoring followed by corneal confocal microscopy and nerve excitability assessments. CONGA, %HG (> 10.0 mmol/l) and %NG (3.9–10.0 mmol/l) were correlated against corneal nerve fibre length and density in the central cornea and inferior whorl region, corneal microneuromas, and a nerve excitability score while controlling for age, sex, diabetes duration and HbA1c. Results: An increase in CONGA [median 2.5 (2.0–3.1) mmol/l] or %HG (mean 46 ± 18%) was associated with a worse nerve excitability score (r = –0.433, P = 0.036 and r = –0.670, P = 0.0012, respectively). By contrast, greater %NG (51 ± 17%) correlated with better nerve excitability scores (r = 0.672, P = 0.0011). Logistic regression revealed that increasing %HG increased the likelihood of abnormal nerve function [odds ratio (OR) 1.11, 95% confidence interval (CI) 1.01–1.23; P = 0.037). An increase in CONGA and %HG were associated with worsening nerve conduction measures, whereas longer %NG correlated with improved nerve conduction variables. CONGA and %HG were associated with inferior whorl corneal nerve fibre length (r = 0.483, P = 0.034 and r = 0.591, P = 0.021, respectively) and number of microneuromas (r = 0.433, P = 0.047 and r = 0.516, P = 0.020, respectively). Conclusions: Short‐term measures of glucose control are associated with impaired nerve function and alterations in corneal nerve morphology. What's new?: Acute measures of glucose control have been associated with retinopathy and microalbuminuria, but their relationship with neuropathy requires exploration.Greater glucose variability and percentage time above range was associated with worsening nerve function.Higher percentage time in range was correlated with better nerve function.Increasing glucose variability and time above range was associated with greater corneal nerve length in the inferior whorl and higher counts of microneuromas.Monitoring of acute measures of glucose control may have more utility than HbA1c in the prevention of diabetic neuropathy. [ABSTRACT FROM AUTHOR]

Objectives Peri- and postoperative pain frequently develops after joint replacement for severe knee osteoarthritis. A continuous nerve block is commonly used for pain relief, but the risks of infection and catheter dislodgement should be considered. The present mini-review aimed to brief the innervation and neural sonoanatomy of the knee joint and summarize the newest evidence of peripheral nerve stimulation (PNS) use in the management of knee pain. Methods We used a systematic approach to search for relevant articles. We used the combination of "peripheral nerve stimulation" and "knee pain" as the key words for the literature search using the electronic database without language or article type restriction. The search period was from the earliest record to August 2019. Results The present review identified six studies, four of which were related to PNS for management of postoperative knee pain and two of which probed neuropathic pain. Most of the studies were either case series or case reports. Based on our search result, PNS is likely to be a feasible and safe treatment for knee pain, but its effectiveness remains uncertain. Conclusions The present review reveals that PNS is feasible for the management of knee pain, especially in the postoperative period. The procedure is safe under ultrasound guidance used for proper placement of the electrodes near the target nerves. In the future, more prospective randomized controlled trials are needed to validate the effectiveness of PNS in acute and chronic knee pain. [ABSTRACT FROM AUTHOR]

Purpose: Ultramarathon running includes two main types of events: single-stage race (SSR) and multistage races (MSR). Direct comparison of neuromuscular fatigue and recovery after SSR versus MSR race of comparable distance and elevation has never been performed. The aim of this study was to assess neuromuscular fatigue and recovery after two ultramarathons of equal distance performed either (i) in a single stage or (ii) in four successive days. Methods: Thirty-one runners participated in the study: 17 ran 169 km in a single-stage race and 14 performed around 40 km·d−1 over 4 d. The two races were performed on the same course. Neuromuscular function was tested before (PRE), after (POST), and 2 (D + 2), 5 (D + 5) and 10 (D + 10) days after the races. Neuromuscular function was evaluated on both knee extensors (KE) and plantar flexors (PF) with voluntary and evoked contractions using electrical (femoral and tibial, respectively) nerve stimulation. Results: Reduction of voluntary activation measured in the KE was greater (i.e., central fatigue) for SSR than MSR directly after the race (−23% vs −7%), P < 0.01). Reductions in evoked mechanical KE and PF responses on relaxed muscle (i.e., peripheral fatigue) of both KE and PF took longer to recover in MSR than in SSR. Conclusions: Performing prolonged running exercise over several days, each separated by rest, elicits more prolonged impairments in contractile function compared with single-stage ultramarathon, whereas single-stage mountain ultramarathon ran on the same course is associated with greater central fatigue. [ABSTRACT FROM AUTHOR]

Introduction: Many reports have indicated that adipose-derived stem cells (ADSCs) are effective for nerve regeneration. We investigated nerve regeneration by combining a polyglycolic acid collagen (PGA-c) tube, which is approved for clinical use, and Schwann cell-like differentiated ADSCs (dADSCs).Methods: Fifteen-millimeter-long gaps in the sciatic nerve of rats were bridged in each group using tubes (group I), with tubes injected with dADSCs (group II), or by resected nerve (group III).Results: Axonal outgrowth was greater in group II than in group I. Tibialis anterior muscle weight revealed recovery only in group III. Latency in nerve conduction studies was equivalent in group II and III, but action potential was lower in group II. Transplanted dADSCs maintained Schwann cell marker expression. ATF3 expression level in the dorsal root ganglia was equivalent in groups II and III.Discussion: dADSCs maintained their differentiated state in the tubes and are believed to have contributed to nerve regeneration. [ABSTRACT FROM AUTHOR]

Context Peripheral nerve damage can occur in a variety of systemic conditions and can have a profound impact on functional and psychological health. Currently, therapeutic interventions for peripheral nerve damage are limited. Objective The aim of this systematic review, conducted in accordance with the Cochrane Collaboration's handbook and reported according to the PRISMA checklist, was to evaluate the efficacy and safety of omega-3 oral supplements for improving peripheral nerve structure and function. Data Sources PubMed, Embase, and Cochrane databases, along with clinical trial registries, were searched from inception to February 2019. Evidence was identified, critically appraised, and synthesized, and the certainty of evidence was appraised using the Grading of Recommendations Assessment, Development and Evaluation approach. Study Selection Randomized controlled trials assessing the effects of omega-3 oral supplementation on outcomes of peripheral nerve structure, peripheral nerve function, or both were eligible for inclusion. Titles and abstracts of identified articles were independently assessed for potential eligibility by 2 review authors. For studies judged as eligible or potentially eligible, full text articles were retrieved and independently assessed by 2 review authors to determine eligibility; disagreements were resolved by consensus. Data Extraction Fifteen trials were included. Two clinically similar studies that investigated the effect of omega-3 supplementation in individuals receiving chemotherapy were meta-analyzed. Pooled data showed a reduced incidence of peripheral neuropathy (RR = 0.58; 95%CI, 0.43–0.77) and a preservation of sensory nerve action potential amplitudes with omega-3 supplementation compared with placebo (MD = 4.19 µV; 95%CI; 2.19–6.19). Conclusion This review finds, with low certainty, that omega-3 supplementation attenuates sensory loss and reduces the incidence of neuropathy secondary to oxaliplatin and paclitaxel treatment relative to placebo. There is currently limited evidence to ascertain whether omega-3 supplementation is beneficial in other systemic conditions characterized by peripheral nerve damage. Systematic Review Registration PROSPERO registration number CRD 42018086297 [ABSTRACT FROM AUTHOR]

Background: Traumatic injury is a major source of chronic pain, particularly for individuals with traumatic fracture of the fibula and/or tibia (lower extremity fracture [LEFx]). Although several factors (e.g., older age, being female, high pain intensity at time of initial injury) have been identified as risk factors for chronic pain associated with LEFx. Comprehensive biopsychosical models to predict the odds of transitioning from acute to chronic pain after LEFx are needed to better understand the underlying processes, predict risk for chronic pain, and develop personalized therapies for individuals at higher risk for developing chronic pain. Objective: The aim of the study was to outline the study design that will be used to examine the physiological, psychological, and genetic/genomic variables—models that predict the transition from acute to chronic pain after LEFx. Method: This prospective descriptive cohort study will enroll 240 participants with a fibula and/or tibia fracture and 40 controls with no LEFx. Data will be collected during an in-hospital baseline visit, five in-person clinic visits (6 weeks, 12 weeks, 24 weeks, 52 weeks, and 24 months), and seven online between-visit surveys (2 weeks, 4 weeks, 8 weeks, 10 weeks, 16 weeks, 20 weeks, and 18 months) from participants with LEFx and at concordant intervals from controls. Measures will consist of 19 questionnaires characterizing pain and psychological status, neurophysiological testing for peripheral sensory nerve function, and peripheral blood samples collections for RNA sequencing. Illumina standard protocols will be used to sequence RNA, and read counts will be used to measure gene expression. Analysis: Direct-entry, multiple logistic regression will be used to produce odds ratios expressing the relative risk on each explanatory variable when controlling for other predictors/covariates in the model. Conclusion: This study is one of the first to longitudinally characterize the biopsychosocial variables associated with a clinically relevant problem of the transition from acute to chronic posttraumatic fracture pain in individuals with LEFx. Results from this study will be used to construct predictive risk models of physiological, psychological, and genetic/genomic variables associated with increased risk for transitioning from acute to chronic pain status after LEFx. This work will lead to a better understanding of the trajectory of pain and relevant variables over time; initiate a better understanding of variables associated with risk for transitioning from acute to chronic pain; and, in the future, could provide a foundation for the identification of novel therapeutic targets to improve the outcomes of individuals with LEFx. [ABSTRACT FROM AUTHOR]

Objective This study aims to assess whether acupuncture analgesia's effects are local or systemic and whether there is a dose response for these effects. Methods Twenty-eight healthy volunteers aged 18–45 were randomized to two doses of acupuncture using points closely associated with peripheral nerves in the legs. The lower-dose group involved acupoints overlying the deep peroneal nerve (DP), and the higher-dose involved acupoints overlying the deep peroneal and posterior tibial nerves (DPTN). Baseline and acupuncture quantitative sensory testing (QST) assessments were obtained locally in the calf and great toe and systemically in the hand. Results were analyzed using factorial repeated-measures analysis of variance for each of the QST variables—cold detection threshold (CDT), vibration detection threshold (VDT), heat pain threshold (HP0.5), and heat pain perception of 5/10 (HP5.0). Location (leg/hand) and time (baseline/acupuncture) were within-subject factors. Intervention (DP/DPTN) was a between-subject factor. Results CDT was increased in the calf (P  < 0.001) and in the hand (P  < 0.001). VDT was increased in the toe (P  < 0.001) but not in the hand. HP0.5 was increased in the calf (P  < 0.001) and in the hand (P  < 0.001). HP5.0 was increased in the calf (P  = 0.002) and in the hand (P  < 0.001), with the local effect being significantly greater than the systemic (P  = 0.004). In all of the above QST modalities, there was no difference between the low-dose (DP) and high-dose (DPTN) acupuncture groups. Conclusions Acupuncture caused comparable local and systemic analgesic effects in cold detection and heat pain perception and only local effects in vibration perception. There was no clear acupuncture dose response to these effects. [ABSTRACT FROM AUTHOR]

Aims: To investigate changes in corneal nerve morphology in Type 2 diabetes and to establish relationships between in vivo corneal confocal microscopy and markers of peripheral nerve structure and function. Participants and methods: We recruited 57 participants with Type 2 diabetes and 26 healthy controls of similar age and sex distribution. We also recruited a disease control group of 54 participants with Type 1 diabetes. All participants were assessed for distal symmetrical polyneuropathy using the Total Neuropathy Score. In vivo corneal confocal microscopy was used to assess corneal nerve fibre length, corneal nerve fibre density, corneal nerve branch density and inferior whorl length. Peripheral nerve structure was assessed using median nerve ultrasonography. Large fibre function was assessed according to median nerve axonal excitability. Small fibre function was assessed using SudoscanTM and the Survey of Autonomic Symptoms. Results: Corneal nerve fibre length, fibre density and branch density and inferior whorl length were significantly lower in individuals with Type 2 diabetes compared to controls (P<0.001 for all). In the Type 2 diabetes cohort, correlations were observed between neuropathy severity and corneal nerve fibre density (P=0.004), corneal nerve branch density (P=0.003), corneal nerve fibre length (P=0.002) and inferior whorl length (P=0.01). Significant correlations were observed between corneal confocal outcomes and axonal excitability measurements. No association was found between corneal confocal microscopy and median nerve cross‐sectional area, Sudoscan measurements or the Survey of Autonomic Symptoms. Conclusions: This study demonstrated significant changes in corneal nerves in individuals with Type 2 diabetes. Reductions in corneal nerve measures correlated with increasing neuropathy severity. Associations were found between corneal confocal microscopy and markers of voltage‐gated potassium channel function. What's new?: In vivo corneal confocal microscopy is a validated diagnostic tool for diabetic peripheral neuropathy in Type 1 diabetes.Multicentre studies have recently demonstrated corneal nerve fibre length (CNFL) to be a valid endpoint for diabetic peripheral neuropathy in Type 2 diabetes.Changes in corneal nerve fibre density (CNFD) were apparent in participants with Type 2 diabetes without neuropathy.CNFL and CNFD were reduced with increasing neuropathy severity.A significant relationship was found between corneal nerves and physiological markers of peripheral nerve function.This study confirms the utility of in vivo corneal confocal microscopy in assessing neuropathy in Type 2 diabetes.Novel insights into the underlying pathophysiology of diabetic peripheral neuropathy in Type 2 diabetes were demonstrated by the significant relationship between corneal nerves and axonal excitability outcomes. [ABSTRACT FROM AUTHOR]

Sensory abnormalities (SAs) are recognized features in Autism Spectrum Disorder (ASD), and a relationship between SAs and ASD traits is also suggested in general population. Our aims were to estimate the prevalence of SAs in three different settings, and to study the association between SAs and quantitative autism traits (QAT) using the Autism Spectrum Screening Questionnaire (ASSQ) and a parental questionnaire. In an epidemiological population of 8-year-old children (n = 4397), the prevalence of SAs was 8.3%, in an ASD sample (n = 28), 53.6%, and in a non-ASD sample (n = 4369), 8.0%, respectively. Tactile and auditory hypersensitivity predicted an ASD diagnosis. The ASSQ was able to differentiate children with and without SA. In conclusion, QAT level and SAs were associated in all study samples. [ABSTRACT FROM AUTHOR]

Background/Objective: The great auricular nerve (GAN) arises from C2‐C3 and provides innervation over the skin in the pre‐auricular region, jaw angle, posteroinferior pinna, and mastoid. Although damage to the GAN has been reported following trauma or procedures nearby this nerve course, neuralgia of this nerve is uncommon with knowledge based on a handful of case reports in literature. The objective of this study is to describe the presentation, treatment, and outcome of 13 cases of GAN neuralgia. Methods: Case series. Retrospecive review of charts from 1994 to 2018 with diagnoses: "auricular neuralgia," "auricular neuritis," or "auricular neuropathy." We included subjects with neuralgic pain within the distribution of the GAN, and excluded patients with atypical facial pain, GAN neuropathy, or unclear etiology. Results: Of 79 charts, 13 patients met criteria (age at onset 11‐59; 11 women, 2 men). Pain was most often described as paroxysmal stabbing provoked by: turning the head (n = 7), touching the neck (n = 5), neck position during sleep (n = 2), jaw movement (n = 2), and other (n = 2). Seven patients received GAN blocks: all noted dramatic improvement in pain, including 3 who continued to receive serial blocks at our institution successfully for the next 2 to 5 years. Two patients successfully transitioned from GAN blocks to GAN stimulators. One patient with GAN lymphoma had resolution of pain following GAN resection. Conclusion: GAN neuralgia should be considered in the differential for periauricular pain. GAN blocks or stimulators may be helpful for pain management. [ABSTRACT FROM AUTHOR]

There is a significant unmet need for novel, effective, and well‐tolerated acute migraine treatments. Remote electrical neuromodulation (REN) is a non‐pharmacological, non‐invasive, acute migraine treatment that stimulates upper arm peripheral nerves to induce conditioned pain modulation – an endogenous analgesic mechanism in which a conditioning stimulation inhibits pain in remote body regions. This review presents the method of action and the clinical data of REN and discusses its potential patient benefits. The clinically meaningful efficacy, together with a very favorable safety profile, suggests that REN may offer a promising alternative for the acute treatment of migraine and could be considered first‐line treatment in some patients. [ABSTRACT FROM AUTHOR]

Aim: Meniere's Disease (MD) is a chronic disease that is characterized by intermittent episodes of tinnitus, vertigo, and progressive- fluctuating sensorineural hearing loss together with aural fullness. The aim of this study is to evaluate Meniere's disease patients with vestibular test battery as Videonystagmography (VNG), Vestibular Evoked Myogenic Potentials (VEMPs) and Video Head Impulse Test (V-HIT) to assess peripheral and central vestibular systems. Methods: 16 bilateral, 17 unilateral patients suffering from MD (mean age, 40.90 years, range, 23 to 66 years; 20 women and 13 men) comprised the study group, and 39 healthy (mean age, 38.10 years, range from 21 to 60 years; 22 women and 17 men) volunteers formed control group. Evaluation of peripheral and central vestibular systems changes with oculomotor tests, caloric test, C-VEMPs, O-VEMPs, and the evaluation of the vestibular ocular reflex (VOR) using the V-HIT. Result: Twenty-six ears out of the forty-nine ears that were affected by Meniere's disease were diagnosed as otolith or ampullary dysfunction. As to O-VEMPs testing, N1 and P1 waves could not be obtained from thirty of the forty-nine ears affected by Meniere's disease. As for obtained N1 and P1 waves, prolonged N1 and P1 wave latencies, and reduced amplitude was observed in Meniere's group. P1 and N1 waves were not observed in 5 bilateral and 2 unilateral Meniere's patients (12 ears out of 49 affected ears) in C-VEMPs recordings (23.9%). In Meniere's patients' group, 44.9% of the velocity gain values were obtained in the pathologic borders of v- HIT. In addition to lower velocity gain, higher ratios of asymmetry were obtained from the ears affected with Meniere's disease. Conclusion: According to these results, it can be concluded that Meniere's disease significantly affects the peripheral vestibular system but the functions of the central vestibular system were not affected. [ABSTRACT FROM AUTHOR]

In this issue of Neuron, Bhat et al. 1 unveil the temporary reawakening of an embryonic guidance program, which facilitates the alignment of blood neovessels, creating a supportive "bridge" microenvironment for axon regrowth and tissue regeneration after peripheral nervous system (PNS) injury., Competing Interests: Declaration of interests The author declares no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Thermal perception is critical for sensing environmental temperature, keeping body temperature consistent, and avoiding thermal danger. Central to thermal perception is the detection of cutaneous (skin) temperature information by the peripheral nerves and its transmission to the spinal cord, thalamus, and downstream cortical areas including the insular cortex, primary somatosensory cortex, and secondary somatosensory cortex. Although much is still unknown about this process, advances in technology have enabled significant progress to be made in recent years.This chapter summarizes our current understanding of how the peripheral nerves, spinal cord, and brain process cutaneous temperature information to give rise to conscious thermal perception., (© 2024. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.)

Background: A major tenet of the alcohol myopia model is that intoxication results in a narrowing of attention to the most central environmental cues, at the cost of more peripheral information. Though long hypothesized, no known study of alcohol myopia has demonstrated differential immediate recall of central and peripheral cues using a standardized task. To address this gap, we conducted an alcohol administration study with a clear, standardized focus—a trauma film. Methods: Ninety‐eight female social drinkers completed self‐report measures, and then were randomized to consume a placebo beverage, a low dose of alcohol (mean breath alcohol concentration [BrAC] = 0.04%), or a high dose of alcohol (mean BrAC = 0.11%). Participants then moved to a staged room where they viewed a film clip depicting a sexual assault. After leaving the room, participants completed a written free recall task of the film and the room. Results: The distinction between recall of central and peripheral details was supported by confirmatory factor analysis. Consistent with the alcohol myopia model, relative to placebo, a high dose of alcohol led to impaired recall of peripheral (but not central) details. Although the interaction between BrAC and information type (central vs. peripheral) was not statistically significant, simple effects revealed a strong association between BrAC and peripheral information, and no association between BrAC and central information. Bolstering myopia as an explanation for our findings, neither central nor peripheral information correlated with self‐reported tendencies to dissociate or distract oneself, or typical alcohol consumption or expectancies. Conclusions: Alcohol myopia can be observed through an immediate free recall task following a stressful film. Additional research is needed to continue evaluating dose‐dependent differential recall in larger samples. This task may be useful for clarifying the role of alcohol myopia in clinical phenomena, such as aggressive behavior and processing traumatic events. [ABSTRACT FROM AUTHOR]