Muscle & Nerve最新文献

{"title":"Placebo-Controlled, Randomized Double-Blind N-Of-1 Trial to Study Safety and Potential Efficacy of TJ-68 for Improving Muscle Cramps in Patients With Amyotrophic Lateral Sclerosis: A Pilot Study.","authors":"Hiroshi Mitsumoto, Ken Cheung, Björn Oskarsson, Grace E Jang, Howard F Andrews, Stephen Johnson, Jaimin S Shah, Joseph Americo Fernandes, Jinsy A Andrews, Maya Rao, Martin McElhiney","doi":"10.1002/mus.28459","DOIUrl":"10.1002/mus.28459","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Muscle cramps are a common symptom in amyotrophic lateral sclerosis (ALS). Ameliorating muscle cramps may improve quality of life in devastating diseases like ALS. A traditional Japanese medicine (Kampo, TJ-68) is widely prescribed in Japan for muscle cramps. However, it is not available in the USA. This study evaluated the safety, tolerability, and efficacy of TJ-68 in ALS.</p><p><strong>Methods: </strong>This study was a double-blind, randomized, placebo-controlled crossover trial, consisting of four periods, conducted at three centers in the USA. Safety was evaluated using multiple measures. The primary efficacy outcome was the Visual Analog Scale for Muscle Cramps Affecting Overall Daily Activity (item #5 of the Muscle Cramp Scale (MCS)). The secondary outcomes included the remaining items of the MCS and the Clinical Global Impression of Changes (CGIC), among others. The study was planned to enroll 22 participants with ALS within 2 years.</p><p><strong>Results: </strong>The enrollment was slow and was completed with 11 participants. There were no serious safety issues and TJ-68 was well tolerated. Although the primary outcome measure did not reach statistical significance (p = 0.35), several secondary measures showed significant results: MCS #1 triggering of cramps (p = 0.01), MCS #2 cramp frequency (p = 0.03), MCS Additional 1 change of motor behaviors (p = 0.02), and CGIC assessed by the evaluator (p = 0.009). Other outcome measures did not reach statistical significance.</p><p><strong>Discussion: </strong>The study revealed that N-of-1 trial design can detect changes in a small sample size, and TJ-68 appeared to be safe. Larger studies are needed to confirm the efficacy of TJ-68.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"485-492"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12338019/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144369088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Concurrent Inclusion Body Myositis and Late Onset Pompe Disease: A Case Report.","authors":"Brianna N Brun, Alexander Tran, Lauren B Adams, Rabi N Tawil, Eric L Logigian, Shawn Jorgensen, Emma Ciafaloni","doi":"10.1002/mus.28427","DOIUrl":"10.1002/mus.28427","url":null,"abstract":"","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"523-526"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144034282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strengths and Opportunities: Clinicians' Perspectives on Palliative Care for Amyotrophic Lateral Sclerosis (ALS) in the United States.","authors":"Kara E Bischoff, Gayle Kojimoto, David L O'Riordan, Yaowaree L Leavell, Samuel Maiser, Astrid Grouls, Alexander K Smith, Steven Z Pantilat, Benzi M Kluger, Ambereen K Mehta","doi":"10.1002/mus.28458","DOIUrl":"10.1002/mus.28458","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Little is known about the state of palliative care (PC) for people with ALS (pALS) in the U.S. We aimed to examine current practice regarding PC for pALS and how it can be improved.</p><p><strong>Methods: </strong>ALS and PC clinicians completed surveys about: (1) strengths and limitations of PC for pALS provided by ALS and PC teams, (2) reasons for and barriers to referring to specialty PC, and (3) how PC could be improved.</p><p><strong>Results: </strong>One hundred forty-one ALS clinicians from 72 institutions and 242 PC clinicians from 96 institutions in 30 states completed surveys. Half of ALS clinicians reported they are able to manage patients' pain (55%) and mood symptoms (52%) \"very well.\" Fewer reported managing care partner needs (43%) and spiritual/existential distress (29%) \"very well.\" Fifty-eight percent of pALS are referred to outpatient PC and 69% to hospice at some point in the illness. Barriers to referring include that PC programs are not sufficiently available to pALS. ALS clinicians generally felt satisfied with PC teams' care, but PC clinicians were less confident managing motor symptoms (51% confident) and helping care partners understand how to provide care (51%) and use equipment (25%). Most clinicians felt the quality of PC provided by ALS (77%) and PC (90%) teams is good/excellent. However, qualitative comments highlighted that both ALS and PC clinicians have knowledge gaps, and collaboration between ALS and PC clinicians should increase.</p><p><strong>Discussion: </strong>Clinician education, expansion of PC services, strengthened collaboration, and further research about PC for pALS are needed.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"455-463"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12338017/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144275373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the Effects of Nusinersen Treatment in Adults With Spinal Muscular Atrophy Using Axonal Excitability and MscanFit MUNE.","authors":"Abir Alaamel, Nazan Şimşek Erdem, Gökçe Yağmur Güneş Gencer, Hüseyin Can Kaya, Hilmi Uysal","doi":"10.1002/mus.28476","DOIUrl":"https://doi.org/10.1002/mus.28476","url":null,"abstract":"<p><strong>Introduction/aims: </strong>The biological changes in motor neurons and motor axons that correlate with the clinical benefits of nusinersen, an antisense oligonucleotide, in spinal muscular atrophy (SMA) remain poorly understood. This study aimed to investigate changes in axonal excitability and motor unit number estimation (MUNE) parameters following a four-dose loading regimen of nusinersen in adult SMA patients.</p><p><strong>Methods: </strong>Adult patients with SMA were assessed using the Hammersmith Functional Motor Scale Expanded (HFMSE) and the Medical Research Council (MRC) scale at baseline and after nusinersen treatment. Axonal excitability studies and MScanFit MUNE were conducted in SMA patients before and after treatment. Baseline axonal excitability and MScanFit MUNE parameters in SMA patients were compared with those of a healthy control (HC) group.</p><p><strong>Results: </strong>Compared to the HC group (n = 10), SMA patients (n = 12) exhibited a significantly prolonged strength-duration time constant (SDTC), a higher resting current/voltage (I/V) slope, and prolonged refractoriness at 2.5 ms. However, no significant changes in axonal excitability parameters were observed following nusinersen treatment. Similarly, there were no significant changes in MUNE or in other parameters, including D50, compound muscle action potentials, and steps%. In contrast, a significant increase in HFMSE and MRC scores was observed after treatment (p < 0.01 and p = 0.01, respectively).</p><p><strong>Discussion: </strong>A prolongation of SDTC, likely due to its effect on sodium channel function, was observed in this study, consistent with existing literature. Despite improvements in motor function, no significant electrophysiological changes were detected in adult SMA patients.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":"72 3","pages":"515-519"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12338010/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144961839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wearable-Derived Patterns of Performance Fatigability During Gait in Spinal Muscular Atrophy.","authors":"Jacqueline Montes, Cara H Kanner, Ton Duong, Rafael Rodriguez-Torres, David Uher, Sally Dunaway Young, Rabia Farooquee, Abby Druffner, Amy Pasternak, Maria Fragala-Pinkham, Damiano Zanotto","doi":"10.1002/mus.28461","DOIUrl":"10.1002/mus.28461","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Despite disease-modifying therapies, fatigability persists in spinal muscular atrophy (SMA). Performance fatigability (PF) during the six-minute walk test (6MWT) is mostly unchanged in treated SMA. This cross-sectional study characterized PF using instrumented insoles.</p><p><strong>Methods: </strong>Ambulatory individuals with SMA (n = 14) and controls (HC) (n = 10) were included. Spatiotemporal and kinetic parameters were collected with custom-engineered instrumented insoles during the 6MWT. Linear mixed models analyzed parameter trends, with trend slope representing PF. Changes in mean velocity (Vavg) and stride-by-stride parameters were compared between minute 1 and 6 and between groups.</p><p><strong>Results: </strong>Decreases in Vavg were greatest for severe SMA (p < 0.001). Changes were found in stride length (SL) (p = 0.048) and stride velocity (SV) (p = 0.030) for severe SMA, and in stance phase (%St) (p = 0.012) and percent terminal double support (%DS) (p = 0.02) for mild SMA. SMA subgroups showed downward trends from minute 1 to 6 in SL, SV, and anterior-posterior center of pressure (AP-COP) (p < 0.001), and increases in Absolute COP-Cyclogram Asymmetry Index (|ASI|) (p < 0.05). Trends differed between severe SMA and other groups for SL, SV, %St, and %DS (p < 0.001), and for AP-COP and |ASI| (p < 0.05). Trends for SL (p < 0.001), SV and AP-COP (p < 0.01) differed between HC and mild SMA.</p><p><strong>Discussion: </strong>PF in SMA manifests as changes in gait parameters. Instrumented insoles revealed fatigue-related changes not captured with the conventional method of comparing the first and last minutes of the 6MWT. Spatiotemporal and kinetic parameters contribute to understanding of impairments and inform therapeutic development.</p><p><strong>Trial registration: </strong>ClinicalTrials.gov: NCT04193085.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"493-501"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144485243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of Anti-3-Hydroxy-3-Methylglutaryl-CoA Reductase (HMGCR) Human Autoantibodies on Muscle Regeneration in Mice.","authors":"Sarah Julien, Honorine Tomasevic, Thara Jaworski, Rachid Zoubairi, Jeremie Martinet, Laurent Drouot, Olivier Boyer","doi":"10.1002/mus.70016","DOIUrl":"https://doi.org/10.1002/mus.70016","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Anti-3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) autoantibodies (aAbs) are pathogenic in immune-mediated necrotizing myopathy (IMNM), partly through complement activation. C5 inhibition did not restore muscle strength in mice or patients with overt IMNM, suggesting additional pathogenic mechanisms. In vitro studies have suggested that anti-HMGCR aAbs might impair myoblast fusion and myotube differentiation, but this has not been investigated in vivo. This study aimed at assessing the impact of anti-HMGCR aAbs on muscle regeneration in a mouse model of muscle necrosis.</p><p><strong>Methods: </strong>Muscle necrosis was induced by cardiotoxin (CTX) injection into the gastrocnemius of C57BL/6 or C5-deficient C57BL/10 mice. Mice received intraperitoneal injections of IgG purified from an anti-HMGCR⁺ IMNM patient every other day. At Days 3 and 6, muscle strength was assessed, blood collected, and muscles frozen for histological analyses.</p><p><strong>Results: </strong>In C5-deficient mice, anti-HMGCR⁺ IgG did not impair muscle regeneration after CTX-induced muscle damage. In contrast, in complement-competent mice, aAbs reduced muscle strength (p = 0.0047), prolonged the presence of myofiber necrosis at Days 3 and 6 (p = 0.0415 and p = 0.0103), and decreased the number of Pax7⁺ (p = 0.0317) and MyoG⁺ (p = 0.0079) regenerating fibers by more than 50% at Day 6.</p><p><strong>Conclusion: </strong>These findings establish the cytotoxicity of anti-HMGCR aAbs on regenerating muscle cells through a primarily complement-mediated mechanism, without directly impairing cellular regeneration per se. Given the still unmet medical needs of IMNM, C5 or upstream complement-targeted therapies early in the disease course, as well as aAb reduction, B/plasma cell depletion via CAR-T cells or bispecific antibodies deserves further clinical investigation.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144961637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LAG3 Is Expressed on Muscle-Infiltrating Cytotoxic T Cells, but Scarce on Circulating T Cells, in Patients With Inclusion Body Myositis.","authors":"Ryuta Mukasa, Seiya Ogata, Naoki Kiyosawa, Tomoko Shibutani, Yoshinori Kashimoto, Kenji Watanabe, Midori Kusama, Hotake Takizawa, Noriko Sato, Ichizo Nishino, Madoka Mori-Yoshimura","doi":"10.1002/mus.28452","DOIUrl":"10.1002/mus.28452","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Selective depletion of muscle-infiltrating pathogenic T cells is a promising therapeutic approach for inclusion body myositis (IBM), but no ideal cell surface antigen that is selectively expressed on these cells has been identified. LAG3 is expressed on highly differentiated, recently activated T cells, but detailed expression profiles in IBM patients have not been reported. This study was intended to bridge this research gap.</p><p><strong>Methods: </strong>First, biobank-stored skeletal muscle tissue samples (biceps or quadriceps) of six IBM patients, which had been biopsied for diagnosis, were used for immunohistochemistry (IHC) for T-cell antigens including LAG3 and CD244, a surface marker of late-differentiated lymphocytes. Next, eight IBM patients were enrolled, and fluorescence-activated cell sorting (FACS) was performed on their blood to count the LAG3-expressing cells. Muscle magnetic resonance imaging (MRI) and whole-blood microarrays were also performed.</p><p><strong>Results: </strong>Upon analyzing LAG3 expression on 41-128 CD3⁺ lymphocytes and 11-86 CD244⁺ lymphocytes counted in the regions of interest (ROIs) for each biobank-stored sample, their positivity rates were 19.3%-48.0% and 41.7%-75.6%, respectively. In contrast, notably few LAG3-expressing cells were present in the blood. Both CD8⁺LAG3⁺ and CD8^-LAG3⁺ cells constituted less than 0.1% of total T cells, although muscle MRI and blood microarray, showing upregulation of the proinflammatory genes GBP1 and GBP5, revealed both myositis and systemic inflammatory conditions in these patients.</p><p><strong>Discussion: </strong>Agents that deplete LAG3⁺ lymphocytes, such as anti-LAG3 antibody that induces antibody-dependent cell cytotoxicity, are potential drug candidates with a favorable efficacy/safety balance for treating IBM.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"443-449"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144248777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Virtual EMG: Safe and Effective Remote Supervision and Reporting.","authors":"Khadija Brouillette, Corey Bacher, Charles D Kassardjian","doi":"10.1002/mus.28479","DOIUrl":"10.1002/mus.28479","url":null,"abstract":"<p><p>The COVID-19 pandemic accelerated the implementation of virtual care in healthcare, revealing challenges and opportunities in the use of remote healthcare services. Electromyography (EMG) traditionally requires in-person interaction, limiting access for patients in remote or underserved areas. This study explores the feasibility of performing needle EMG remotely, a concept referred to as \"virtual EMG,\" whereby an experienced clinician supervises a technician from a different location using virtual tools. We developed a system utilizing remote video technology, a high-resolution camera, and Bluetooth communication devices to allow real-time observation and guidance of EMG procedures. The system was tested across three phases: (1) initial setup within the same facility, (2) refinement with higher quality video and communication tools, and (3) application in a clinical scenario involving a complex patient case. Our findings suggest that virtual EMG can be performed safely and effectively, providing accurate diagnostic information while reducing the need for patient travel and in-person contact. The implementation of virtual EMG has the potential to improve access to neuromuscular diagnostics, especially in rural and remote areas, aligning with the healthcare goals of enhancing patient experience, reducing costs, and promoting access. Further investigations are needed to validate this approach across various clinical scenarios and geographical locations.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"393-398"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144642983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Phase 1, Double-Blind, Placebo-Controlled Trial of Sevasemten (EDG-5506), a Selective Modulator of Fast Skeletal Muscle Contraction, in Healthy Volunteers and Adults With Becker Muscular Dystrophy.","authors":"Joanne Donovan, Jeffrey A Silverman, Ben Barthel, Michael DuVall, Molly Madden, James MacDougall, Nicole Rempel Kilburn, Abby Bronson, Marc Evanchik, Gilad Gordon, Kevin Koch, Alan J Russell","doi":"10.1002/mus.28444","DOIUrl":"10.1002/mus.28444","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Sevasemten (EDG-5506) is an orally administered, investigational small molecule that selectively modulates fast muscle fiber contraction by inhibiting fast myosin ATPase. This study assessed the safety, tolerability, and pharmacokinetics (PK)/pharmacodynamics (PD) of sevasemten in healthy adult volunteers (HVs) and adults with Becker muscular dystrophy (BMD).</p><p><strong>Methods: </strong>This randomized, double-blind, placebo-controlled phase 1 study was conducted at a single site. Eligible participants were 18-55 years of age with a body mass index < 30 kg/m²; adults with BMD were required to have a confirmed diagnosis based on documentation of pathogenic variant(s) in the dystrophin gene and a BMD phenotype. Participants were randomized 3:1 to receive sevasemten or placebo for up to 14 days. Endpoints included adverse events (AEs), sevasemten PK and muscle concentration, and changes in biomarkers of muscle injury.</p><p><strong>Results: </strong>The study enrolled 97 HVs in 7 single-dose cohorts (N = 57) and 5 multiple-dose cohorts (N = 40). Seven adults with BMD were enrolled in a multiple-dose cohort. There were no serious AEs or AEs leading to trial discontinuation; the most common AEs were dizziness and somnolence. For adults with BMD, serum biomarkers of muscle injury trended down progressively with sevasemten treatment (average maximal reductions of 70% for creatine kinase, 98% for fast skeletal muscle troponin I, and 45% for myoglobin). Plasma proteomic analysis identified a signature of 125 elevated proteins characteristic of BMD that was reversibly lowered with sevasemten treatment.</p><p><strong>Discussion: </strong>Sevasemten was generally well tolerated. Preliminary observations of decreases in biomarkers of muscle damage in adults with BMD support further clinical development.</p><p><strong>Trial registration: </strong>NCT04585464.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"399-407"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12338012/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144199591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing MScanFit MUNE in Amyotrophic Lateral Sclerosis: Influence of Nerve Conduction Distance and Temporal Dispersion.","authors":"Halil Can Alaydin, Ozlem Kurtkaya Kocak, Ilker Arslan, Hasan Kılınc, H Evren Boran, Hatice Tankisi, Bulent Cengiz","doi":"10.1002/mus.28446","DOIUrl":"10.1002/mus.28446","url":null,"abstract":"<p><strong>Introduction/aims: </strong>MScanFit is a promising method for motor unit number estimation (MUNE) based on compound muscle action potential (CMAP) scanning. Considering that CMAP morphology may be altered by temporal dispersion associated with nerve conduction distance, it is important to evaluate the potential impact of these changes on MScanFit measurements. Therefore, we aimed to investigate the effect of nerve conduction distance on MScanFit MUNE in patients with amyotrophic lateral sclerosis (ALS).</p><p><strong>Methods: </strong>MScanFit MUNE was recorded from the abductor digiti minimi (ADM) muscle by stimulating the ulnar nerve at the wrist and elbow in twenty-three ALS patients. Consistency of MScanFit MUNE and size parameters, CMAP amplitude, and CMAP duration were evaluated using intraclass correlation coefficients (ICC).</p><p><strong>Results: </strong>Significant differences were noted in CMAP amplitudes (6.35 ± 2.5 mV vs. 5.7 ± 2.4 mV; p = 0.003) and CMAP durations (5.8 ± 0.7 ms vs. 6.2 ± 0.8 ms; p < 0.001), reflecting temporal dispersion effects. MUNE values showed high consistency between wrist and elbow stimulations (61 ± 32.4 vs. 61.1 ± 30.7; p = 0.99), with an ICC of 0.86. Similar repeatability was also observed for MScanFit size parameters.</p><p><strong>Discussion: </strong>The reliability of MScanFit MUNE in determining motor unit values in ALS patients remains consistent regardless of the stimulation distance. Our findings highlight the effectiveness of MScanFit MUNE in evaluating motor unit loss of ALS patients and demonstrate its resilience to temporal dispersion effects. Proximal stimulation serves as a viable alternative, enhancing the utility of MScanFit in clinical settings.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"408-415"},"PeriodicalIF":3.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144208931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}