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Introduction/aims: Neuromuscular ultrasound (NMUS) is gaining prominence as a valuable tool for diagnosing neuromuscular disorders at the point of care. Neuromuscular disorder diagnostic criteria guidelines have begun incorporating NMUS findings. As interest grows, fellowship programs must consider incorporating training into their curricula. This study evaluated the current state of NMUS training, potential barriers, and interest in training across Canadian neuromuscular fellowship programs., Methods: A 23-question online survey was developed and distributed via email to all 10 neuromuscular fellowship program directors across Canada., Results: Seven (70%) programs responded to the survey. There was general agreement among programs on the value of NMUS, however, only one (14.3%) program reported they would consider recent graduates to be competent in NMUS. Critical barriers to incorporation of NMUS training included lack of a formalized curriculum, faculty expertise and time, and equipment. Two (28.6%) programs reported that accessibility of equipment and one (14.3%) that faculty expertise was not a barrier to NMUS training. Two (28.6%) programs have local NMUS training options available to fellows (in only one program is NMUS training mandatory). All programs expressed interest in additional training opportunities, and three (43%) programs reported taking steps toward incorporating NMUS training into their curricula., Discussion: NMUS training is in its infancy in Canada, with several common barriers identified across programs. There is universal interest in further NMUS training opportunities for fellows, highlighting the importance of a common approach to addressing the educational gap to support development of formalized NMUS training mechanisms in Canada., (© 2025 Wiley Periodicals LLC.)

Objectives: Guillain-Barré syndrome (GBS) and myasthenia gravis (MG) are the most common causes of acute neuromuscular respiratory failure resulting in ICU admission. This synthetic narrative review summarizes the evidence for the prediction and management of acute neuromuscular respiratory failure due to GBS and MG., Data Sources: We searched PubMed for relevant literature and reviewed bibliographies of included articles for additional relevant studies., Study Selection: English-language publications were reviewed., Data Extraction: Data regarding study methodology, patient population, evaluation metrics, respiratory interventions, and clinical outcomes were qualitatively assessed., Data Synthesis: No single tool has sufficient sensitivity and specificity for the prediction of acute neuromuscular respiratory failure requiring mechanical ventilation. Multimodal assessment, integrating history, examination maneuvers (single breath count, neck flexion strength, bulbar weakness, and paradoxical breathing) and pulmonary function testing are ideal for risk stratification. The Erasmus GBS Respiratory Insufficiency Score is a validated tool useful for GBS. Noninvasive ventilation can be effective in MG but may not be safe in early GBS. Airway management considerations are similar across both conditions, but dysautonomia in GBS requires specific attention. Extubation failure is common in MG, and early tracheostomy may be beneficial for MG. Prolonged ventilatory support is common, and good functional outcomes may occur even when prolonged ventilation is required., Conclusions: Multimodal assessments integrating several bedside indicators of bulbar and respiratory muscle function can aid in evidence-based risk stratification for respiratory failure among those with neuromuscular disease. Serial evaluations may help establish a patient's trajectory and to determine timing of respiratory intervention., Competing Interests: Dr. Mobach received funding from Biogen, Amylyx, Mitsubishi Tanabe, and Quralis. Dr. Rabinstein serves on the Clinical Events Classification committee for Boston Scientific and serves on advisory boards for Astra Zeneca, Shionogi, Brainomix, and Chiesi. The remaining authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2024 by the Society of Critical Care Medicine and Wolters Kluwer Health, Inc. All Rights Reserved.)

Background: Hexanucleotide repeat expansion of C9orf72 is a common genetic cause of amyotrophic lateral sclerosis (ALS). No C9orf72-targeted treatments are available. BIIB078 is an investigational antisense oligonucleotide targeting C9orf72 sense RNA. We aimed to assess the safety, tolerability, and pharmacokinetics of BIIB078 in participants with C9orf72-associated ALS., Methods: This phase 1, randomised controlled trial was done at 22 sites in six countries (Canada, Ireland, Netherlands, Switzerland, UK, and USA). Adults with ALS and a pathogenic repeat expansion in C9orf72 were randomly assigned within six cohorts, via Interactive Response Technology in a 3:1 ratio per cohort, to receive BIIB078 (5 mg, 10 mg, 20 mg, 35 mg, 60 mg, or 90 mg in cohorts 1-6, respectively) or placebo, via an intrathecal bolus injection. The treatment period consisted of three loading doses of study treatment, administered approximately once every 2 weeks, followed by monthly maintenance doses during a treatment period of about 3 months for cohorts 1-3 and about 6 months for cohorts 4-6. Patients and investigators were masked to treatment assignment. The primary endpoint was the incidence of adverse events and serious adverse events. This trial was registered with ClinicalTrials.gov (NCT03626012) and is completed., Findings: Between Sept 10, 2018, and Nov 17, 2021, 124 patients were screened for inclusion in the study. 18 patients were excluded and 106 participants were enrolled and randomly assigned to receive 5 mg (n=6), 10 mg (n=9), 20 mg (n=9), 35 mg (n=19), 60 mg (n=18), or 90 mg (n=18) of BIIB078, or placebo (n=27). 58 (55%) of 106 patients were female. All patients received at least one dose of study treatment and were included in all analyses. All participants had at least one adverse event; most adverse events were mild or moderate in severity and did not lead to treatment discontinuation. The most common adverse events in BIIB078-treated participants were falls, procedural pain, headache, and post lumbar puncture syndrome. 14 (18%) of 79 patients who received any dose of BIIB078 reported serious adverse events, compared with nine (33%) of 27 patients who received placebo. Five participants who received BIIB078 and three participants who received placebo had fatal adverse events: respiratory failure in a participant who received 10 mg BIIB078, ALS worsening in two participants who received 35 mg BIIB078, traumatic intracerebral haemorrhage in one participant who received 35 mg BIIB078, pulmonary embolism in one participant who received 60 mg BIIB078, and respiratory failure in three participants who received placebo. All deaths were assessed as not related to the study treatment by the reporting investigator., Interpretation: On the basis of these phase 1 study results, including secondary and exploratory findings showing no reduction in neurofilament levels and no benefit on clinical outcomes relative to the placebo cohort, BIIB078 clinical development has been discontinued. However, these results will be informative in furthering our understanding of the complex pathobiology of C9orf72-associated ALS., Funding: Biogen., Competing Interests: Declaration of interests LHvdB: advisory board for Amylyx, Biogen, Cytokinetics, Denali, QurAlis, Corcept, Novartis, Ferrer, and Sanofi. JDR: advisory board for Expansion Therapeutics and Sanofi and receives support from AbbVie Foundation, ALS Association, ALS Finding a Cure Foundation, American Airlines, Answer ALS Foundation, Aviators Against ALS, Bruce Edwards Foundation, Calico, Caterpillar Foundation, Chan Zuckerberg Initiative, Fishman Family Foundation, F Prime, Glaxo Smith Kline, Microsoft, M Armstrong, Muscular Dystrophy Association, National Football League, National Institutes of Health, Stay, Strong Vs ALS, Team Gleason, The Judith and Jean Pape Adams Charitable Foundation, Travelers Insurance, and the US Department of Defense. PJS: advisory board member for Aclipse Therapeutics, Benevolent AI, Biogen, Bristol Meyers Squibb, Darby Rimmer Foundation, Lilly, Novartis, Quell Therapeutics, QurAlis, Samsara Therapeutics, and Pangea Botanica; receives research support from US Department of Defense, EU Horizon 2020, EU Innovative Medicines Initiative, Fight MND, LifeArc, the Medical Research Council, MND Association, My Name'5 Doddie Foundation, NIHR, Pfizer, Quell Therapeutics, SwanBio, and Wolfson Foundation; and has received support for clinical trials participation from Alexion, Biogen, the EU Horizon programme, and UK NIHR. SB: received research funding from National Institutes of Health, American Academy of Neurology, American Association for Electrodiagnostic and Neuromuscular Medicine (AANEM), Muscular Dystrophy Association, OrphAI Therapeutics, Biogen, Ionis, Medicinova, Novartis, Orion, Voyager Therapeutics, and Denali Therapeutics; honoraria for patient and clinician educational activities related to ALS from AANEM Foundation, McCourt Foundation, and Medscape; institutional consulting or advisory board fees from OrphAI Therapeutics and Biogen; and platform trial coordination centre activities from HEALEY ALS. MB: consultant to Alector, Annexon, Arrowhead, Biogen, Denali, Eli Lilly, Novartis, Roche, Sanofi, UniQure, and Woolsey; clinical trial site investigator for Biogen and Orphazyme; and intellectual property licensed to Biogen and Orphazyme. RCB: advisory board for MT Pharma, has a consulting role with Biogen, has Equity in Neuroquestions LLC, and receives a recurring annual gift from a patient's family for research on neuralgic amyotrophy. AG: ad hoc consultant for genetic testing for Biogen; consultant on ALS trial design for Alexion, AL-S Pharma, Calico, Cytokinetics, and Sanofi; and CMO at QurAlis. JDG: institution was contracted by Biogen as a trial site and was paid for those services; received grants from Muscular Dystrophy Association and National Institutes of Health The Amyotrophic Lateral Sclerosis Association and received commercial sponsorships for clinical trials from Amylyx, Biogen, Cytokinetics, and Neuralstem. OH: funding from Science Foundation Ireland (grants SFI 16/RC/3948 and 20/SP/8953); received consulting fees from Accelsior, Biogen, Cytokinetics, Denali, Novartis, Orion, and Wave Pharmaceuticals; and is Editor-in-Chief of the journal Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration. VL: institution was contracted by Biogen as a trial site and was paid for those services; and Chair of independent data monitoring committee at Vico Therapeutics and member of independent data monitoring committees at QurAlis and Cyclo Therapeutics. TM: consultant to Amylyx, Biogen, Cytokinetics, and QurAlis. BO: serves as a consultant for Columbia University/Tsumura, MediciNova, Biogen, UniQure, Amylyx, and Mitsubishi and has research grants from Columbia University/Tsumura, Biogen, MediciNova, Cytokinetics, Mitsubishi, Calico, Novartis, Sanofi, Ashvattha, and TARGET ALS. GLP: medical advisory roles for Amylyx, Avanir, Biogen, Catalyst, Cytokinetics, MT Pharma, Otsuka, and the US Department of Defense. JR: serves on advisory boards to Libra, Golgi, and Transposon and consultant to Verge, Iris, and Zydus. MW: consultant to Allmiral, Biogen, Mitsubishi Tanabe Pharma, Neuraxpharm, and Novartis. LZ: received honorarium for being on a Biogen advisory board. PJ-n and FR: paid employees of Ionis Pharmaceuticals. LL, DG, MM, JI, SS, SG, and SF: employees of and may hold stock in Biogen. TAF, ALG, and SE: employees of Biogen at the time the study was conducted. CES: declares no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved, including those for text and data mining, AI training, and similar technologies.)

Purpose: To assess whether there is a measurable impairment of median nerve conduction study parameters with uncomplicated distal radius fracture., Methods: Patients were assessed prospectively at the time of cast removal (visit 1) after a standard 6-8 week immobilization for uncomplicated distal radius fracture. Patients with prior entrapment neuropathy or polyneuropathy were excluded. Patients were asked to report sensory symptoms. Median and ulnar motor and sensory conduction studies were performed bilaterally, as well as transcarpal stimulation. All electrophysiologic studies were repeated at a follow-up visit 2, on average 7.8 weeks later., Results: 39 patients were assessed at visit 1 and 30 (77%) were available for follow-up visit 2. Paresthesia in the median territory on the fractured side were reported in 20% at visit 1 and 26% at visit 2. Electrophysiological evidence of only mild carpal tunnel syndrome was found on the fractured side in 4/39 at visit 1 and 6/30 at visit 2. There were only 2 cases of moderate-marked median neuropathy, both asymptomatic and on the unfractured side. Median motor and sensory latencies and amplitudes did not show statistically significant differences between fractured and unfractured sides with the single exception of median distal motor latency at visit 1., Conclusions: Median territory paresthesia at the time of cast removal following distal radius fracture are often not associated with electrophysiologic evidence of median neuropathy. Most median nerve electrophysiologic parameters do not significantly differ between the fractured and uninjured sides. Significant traumatic median neuropathy is not likely to be a frequent manifestation of uncomplicated distal radius fracture., Level of Evidence: Diagnostic analysis, Level III., Competing Interests: The authors have declared that no competing interests exist.

Background: Disuse atrophy from immobilization is the result of decreased neural activity and muscle unloading., Methods: We studied the impact of disuse on hand intrinsic compound muscle action potentials (CMAPs) in a cohort of 39 patients with unilateral 6-week immobilization of the hand in a cast, after distal radius fracture. We excluded patients with nerve injury. We compared side-to-side CMAP characteristics at the time of cast removal and at a subsequent follow-up visit, after a mean interval of 7.8 weeks., Results: Statistically significant reductions in CMAP amplitude were noted for the abductor pollicis brevis (29.2%), abductor digiti minimi (19.0%), and first dorsal interosseus (24.9%). There was partial repair of the relative CMAP reduction at the follow-up visit (20.1%, 10.7%, and 8.7%, respectively). There was no significant change in CMAP duration., Conclusions: These results provide a framework for quantifying the degree of hand intrinsic CMAP amplitude reduction attributed to disuse., (© 2019 Wiley Periodicals, Inc.)

Monomelic pure motor amyotrophy may seem to be an ominous syndrome as it leads to consideration of motor neuron disease. We present a series of 3 very similar cases where unilateral pure distal lower motor neuron paresis and atrophy was limited to the C8-T1 myotomes, without long-tract signs. Electrodiagnostic studies were in keeping with a restricted anterior horn cell disorder. Neuroimaging showed very focal spinal cord compression at the C6-7 level. Two patients underwent surgical decompression. All 3 patients were improved or stable at follow-up. Distal spondylotic amyotrophy is characterized by equal involvement of thenar and hypothenar muscles, in contrast to amyotrophic lateral sclerosis or Hirayama disease. We discuss the striking 2-level discrepancy between imaging and clinical localization. Proposed explanations are arterial or venous compromise caudal to the site of compression. Anatomical variation such as a prefixed brachial plexus is unlikely. A similar imaging/clinical discrepancy has been documented in Hirayama disease and spondylotic myelopathy.