{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T16:08:09Z","timestamp":1753891689720,"version":"3.41.2"},"reference-count":41,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,12,21]],"date-time":"2021-12-21T00:00:00Z","timestamp":1640044800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurol."],"abstract":"<jats:p>The aim of this study was to evaluate the usefulness of the motor unit number index (MUNIX) technique in Kennedy disease (KD) and test the correlation between the MUNIX and other clinical parameters. The MUNIX values of the bilateral deltoid, abductor digiti minimi (ADM), quadriceps femoris (QF), and tibialis anterior (TA) were determined and compared with the course of the disease. The MUNIX sum score was calculated by adding the MUNIX values of these 8 muscles. Disability was evaluated using the spinal and bulbar muscular atrophy functional rating scale (SBMAFRS). The MUNIX scores of patients with KD were negatively correlated with the course of the disease (<jats:italic>p<\/jats:italic> &amp;lt; 0.05), whereas their motor unit size index (MUSIX) scores were positively correlated with the course the of disease (<jats:italic>p<\/jats:italic> &amp;lt; 0.05). MUNIX sum scores were correlated with SBMAFRS scores (<jats:italic>r<\/jats:italic> = 0.714, <jats:italic>p<\/jats:italic> &amp;lt; 0.05). MUNIX was more sensitive than compound muscle action potentials or muscle strength as an indicator of neuron loss and axonal collateral reinnervation. The MUNIX sum score is an objective and a reliable indicator of disease progression, and it is a potential choice for therapeutic clinical trials. The MUNIX can assess the functional loss of motor axons and is correlated with disability. The MUNIX sum score may be especially suitable as an objective parameter.<\/jats:p>","DOI":"10.3389\/fneur.2021.705816","type":"journal-article","created":{"date-parts":[[2021,12,21]],"date-time":"2021-12-21T05:24:33Z","timestamp":1640064273000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Application Value of the Motor Unit Number Index in Patients With Kennedy Disease"],"prefix":"10.3389","volume":"12","author":[{"given":"Shuo","family":"Zhang","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xin","family":"Yang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yingsheng","family":"Xu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongmei","family":"Luo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dongsheng","family":"Fan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoxuan","family":"Liu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2021,12,21]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"199","DOI":"10.5414\/NP300829","article-title":"Morphological changes of skeletal muscle in spinal and bulbar muscular atrophy (SBMA), Kennedy's disease: a case report","volume":"34","author":"Acewicz","year":"2015","journal-title":"Clin Neuropathol."},{"key":"B2","doi-asserted-by":"publisher","first-page":"2077","DOI":"10.1212\/WNL.0000000000000507","article-title":"Correlation of clinical and molecular features in spinal bulbar muscular atrophy","volume":"82","author":"Fratta","year":"2014","journal-title":"Neurology."},{"key":"B3","doi-asserted-by":"publisher","first-page":"298","DOI":"10.1007\/s00109-004-0530-7","article-title":"Spinal and bulbar muscular atrophy: ligand-dependent pathogenesis and therapeutic perspectives","volume":"82","author":"Katsuno","year":"2004","journal-title":"J Mol Med."},{"key":"B4","doi-asserted-by":"publisher","first-page":"1390","DOI":"10.1016\/j.clinph.2018.04.359","article-title":"Motor unit number index correlates with disability in Charcot-Marie-Tooth disease","volume":"129","author":"Bas","year":"2018","journal-title":"Clin Neurophysiol."},{"key":"B5","doi-asserted-by":"publisher","first-page":"1516","DOI":"10.1093\/brain\/123.7.1516","article-title":"Neurological dysfunction and axonal degeneration in Charcot-Marie-Tooth disease type 1A","volume":"123","author":"Krajewski","year":"2000","journal-title":"Brain."},{"key":"B6","doi-asserted-by":"publisher","first-page":"955","DOI":"10.1016\/S1388-2457(01)00520-X","article-title":"Motor unit number estimation in human neurological diseases and animal models","volume":"112","author":"Shefner","year":"2001","journal-title":"Clin Neurophysiol."},{"key":"B7","doi-asserted-by":"publisher","first-page":"2670","DOI":"10.1016\/j.clinph.2016.03.024","article-title":"Lower motor neuron dysfunction in ALS","volume":"127","author":"de Carvalho","year":"2016","journal-title":"Clin Neurophysiol."},{"key":"B8","doi-asserted-by":"publisher","first-page":"3051","DOI":"10.3760\/cma.j.issn.0376-2491.2009.43.008","article-title":"Comparison of multiple point stimulation and incremental stimulation in patients with amyotrophic lateral sclerosis","volume":"89","author":"Xu","year":"2009","journal-title":"Zhonghua Yi Xue Za Zhi."},{"key":"B9","doi-asserted-by":"publisher","first-page":"1172","DOI":"10.1136\/jnnp-2015-310509","article-title":"Tracking motor neuron loss in a set of six muscles in amyotrophic lateral sclerosis using the Motor Unit Number Index (MUNIX): a 15-month longitudinal multicentre trial","volume":"86","author":"Neuwirth","year":"2015","journal-title":"J Neurol Neurosurg Psychiatry."},{"key":"B10","doi-asserted-by":"publisher","first-page":"60","DOI":"10.1016\/j.jelekin.2015.11.001","article-title":"Motor unit number estimation as a complementary test to routine electromyography in the diagnosis of amyotrophic lateral sclerosis","volume":"26","author":"Gawel","year":"2016","journal-title":"J Electromyogr Kinesiol."},{"key":"B11","doi-asserted-by":"publisher","first-page":"69","DOI":"10.1007\/s13311-016-0473-z","article-title":"Assessment of motor units in neuromuscular disease","volume":"14","author":"Henderson","year":"2017","journal-title":"Neurotherapeutics."},{"key":"B12","doi-asserted-by":"publisher","first-page":"365","DOI":"10.1002\/mus.20266","article-title":"Decomposition-based quantitative electromyography: effect of force on motor unit potentials and motor unit number estimates","volume":"31","author":"Boe","year":"2005","journal-title":"Muscle Nerve."},{"key":"B13","doi-asserted-by":"publisher","first-page":"3059","DOI":"10.1016\/j.clinph.2016.06.014","article-title":"Motor unit number estimation based on high-density surface electromyography decomposition","volume":"127","author":"Peng","year":"2016","journal-title":"Clin Neurophysiol."},{"key":"B14","doi-asserted-by":"publisher","first-page":"889","DOI":"10.1002\/mus.24945","article-title":"Estimating motor unit numbers from a CMAP scan","volume":"53","author":"Bostock","year":"2016","journal-title":"Muscle Nerve."},{"key":"B15","doi-asserted-by":"publisher","first-page":"2209","DOI":"10.1109\/TBME.2004.834281","article-title":"Motor unit number index (MUNIX)","volume":"51","author":"Nandedkar","year":"2004","journal-title":"IEEE Trans Biomed Eng."},{"key":"B16","doi-asserted-by":"publisher","first-page":"235","DOI":"10.1016\/j.clinph.2016.11.012","article-title":"Monitoring the short-term effect of intravenous immunoglobulins in multifocal motor neuropathy using motor unit number index","volume":"128","author":"Philibert","year":"2017","journal-title":"Clin Neurophysiol."},{"key":"B17","doi-asserted-by":"publisher","first-page":"898","DOI":"10.1016\/j.clinph.2015.05.004","article-title":"Axonal loss in patients with inflammatory demyelinating polyneuropathy as determined by motor unit number estimation and MUNIX","volume":"127","author":"Paramanathan","year":"2016","journal-title":"Clin Neurophysiol."},{"key":"B18","doi-asserted-by":"publisher","first-page":"808","DOI":"10.1002\/mus.21765","article-title":"Reproducibility of the motor unit number index (MUNIX) in normal controls and amyotrophic lateral sclerosis patients","volume":"42","author":"Ahn","year":"2010","journal-title":"Muscle Nerve."},{"key":"B19","doi-asserted-by":"publisher","first-page":"1644","DOI":"10.1016\/j.clinph.2012.01.004","article-title":"Motor unit number index (MUNIX) versus motor unit number estimation (MUNE): a direct comparison in a longitudinal study of ALS patients","volume":"123","author":"Boekestein","year":"2012","journal-title":"Clin Neurophysiol."},{"key":"B20","doi-asserted-by":"publisher","first-page":"610","DOI":"10.1016\/j.clinph.2012.08.023","article-title":"MUNIX and incremental stimulation MUNE in ALS patients and control subjects","volume":"124","author":"Furtula","year":"2013","journal-title":"Clin Neurophysiol."},{"key":"B21","doi-asserted-by":"publisher","first-page":"505","DOI":"10.1109\/TITB.2011.2140379","article-title":"Motor unit number reductions in paretic muscles of stroke survivors","volume":"15","author":"Li","year":"2011","journal-title":"IEEE Trans Inform Technol Biomed."},{"key":"B22","doi-asserted-by":"publisher","first-page":"2891","DOI":"10.1109\/TBME.2014.2333034","article-title":"Examination of hand muscle activation and motor unit indices derived from surface EMG in chronic stroke","volume":"61","author":"Li","year":"2014","journal-title":"IEEE Trans Biomed Eng."},{"key":"B23","doi-asserted-by":"publisher","first-page":"1143","DOI":"10.1109\/TITB.2012.2193410","article-title":"an examination of the motor unit number index (MUNIX) in muscles paralyzed by spinal cord injury","volume":"16","author":"Li","year":"2012","journal-title":"IEEE Trans Inform Technol Biomed."},{"key":"B24","doi-asserted-by":"publisher","first-page":"444","DOI":"10.1016\/j.jelekin.2015.02.007","article-title":"An examination of motor unit number index in adults with cerebral palsy","volume":"25","author":"Marciniak","year":"2015","journal-title":"J Electromyogr Kinesiol."},{"key":"B25","doi-asserted-by":"publisher","first-page":"6","DOI":"10.1111\/odi.12121","article-title":"Spinal and bulbar muscular atrophy: pathogenesis and clinical management","volume":"20","author":"Grunseich","year":"2014","journal-title":"Oral Dis."},{"key":"B26","doi-asserted-by":"publisher","first-page":"554","DOI":"10.1016\/j.nmd.2015.03.008","article-title":"A functional scale for spinal and bulbar muscular atrophy: cross-sectional and longitudinal study","volume":"25","author":"Hashizume","year":"2015","journal-title":"Neuromuscul Disord."},{"key":"B27","doi-asserted-by":"publisher","first-page":"798","DOI":"10.1002\/mus.21824","article-title":"Motor unit number index (MUNIX): principle, method, and findings in healthy subjects and in patients with motor neuron disease","volume":"42","author":"Nandedkar","year":"2010","journal-title":"Muscle Nerve."},{"key":"B28","doi-asserted-by":"publisher","first-page":"1792","DOI":"10.1007\/s00415-020-10332-5","article-title":"Development of new outcome measures for adult SMA type III and IV: a multimodal longitudinal study","volume":"268","author":"Querin","year":"2021","journal-title":"J Neurol."},{"key":"B29","doi-asserted-by":"publisher","first-page":"90","DOI":"10.1186\/s13023-020-01366-z","article-title":"The French national protocol for Kennedy's disease (SBMA): consensus diagnostic and management recommendations","volume":"15","author":"Pradat","year":"2020","journal-title":"Orphanet J Rare Dis."},{"key":"B30","doi-asserted-by":"publisher","first-page":"699","DOI":"10.1080\/1357650X.2015.1041971","article-title":"Motor unit number index examination in dominant and non-dominant hand muscles","volume":"20","author":"Li","year":"2015","journal-title":"Laterality."},{"key":"B31","doi-asserted-by":"publisher","first-page":"115","DOI":"10.1016\/j.medengphy.2015.11.002","article-title":"Modified motor unit number index: a simulation study of the first dorsal interosseous muscle","volume":"38","author":"Li","year":"2016","journal-title":"Med Eng Phys."},{"key":"B32","doi-asserted-by":"publisher","first-page":"809","DOI":"10.1002\/mus.21399","article-title":"Standard and modified statistical MUNE evaluations in spinal-bulbar muscular atrophy","volume":"40","author":"Lehky","year":"2009","journal-title":"Muscle Nerve."},{"key":"B33","doi-asserted-by":"publisher","first-page":"135488","DOI":"10.1016\/j.neulet.2020.135488","article-title":"Use of CMAP, MScan fit-MUNE, and MUNIX in understanding neurodegeneration pattern of ALS and detection of early motor neuron loss in daily practice","volume":"741","author":"Gunes","year":"2021","journal-title":"Neurosci Lett."},{"key":"B34","doi-asserted-by":"publisher","first-page":"2979","DOI":"10.1016\/j.clinph.2016.06.011","article-title":"MUNIX: reproducibility and clinical correlations in amyotrophic lateral sclerosis","volume":"127","author":"Escorcio-Bezerra","year":"2016","journal-title":"Clin Neurophysiol."},{"key":"B35","doi-asserted-by":"publisher","first-page":"304","DOI":"10.1002\/mus.21144","article-title":"Stratifying disease stages with different progression rates determined by electrophysiological tests in patients with amyotrophic lateral sclerosis","volume":"39","author":"Liu","year":"2009","journal-title":"Muscle Nerve."},{"key":"B36","doi-asserted-by":"publisher","first-page":"2209","DOI":"10.1016\/j.clinph.2020.06.019","article-title":"Motor unit number index as an individual biomarker: reference limits of intra-individual variability over time in healthy subjects","volume":"131","author":"Delmont","year":"2020","journal-title":"Clin Neurophysiol."},{"key":"B37","doi-asserted-by":"publisher","first-page":"659","DOI":"10.1093\/brain\/awh381","article-title":"Widespread nuclear and cytoplasmic accumulation of mutant androgen receptor in SBMA patients","volume":"128","author":"Adachi","year":"2005","journal-title":"Brain."},{"key":"B38","doi-asserted-by":"publisher","first-page":"433","DOI":"10.1016\/j.clinph.2012.08.022","article-title":"MUNIX and MUNE in ALS","volume":"124","author":"Bromberg","year":"2013","journal-title":"Clin Neurophysiol."},{"key":"B39","doi-asserted-by":"publisher","first-page":"297","DOI":"10.1109\/TNSRE.2012.2194311","article-title":"A simulation-based analysis of motor unit number index (MUNIX) technique using motoneuron pool and surface electromyogram models","volume":"20","author":"Li","year":"2012","journal-title":"IEEE Trans Neural Syst Rehabil Eng."},{"key":"B40","doi-asserted-by":"publisher","first-page":"329","DOI":"10.1016\/j.neucli.2019.07.002","article-title":"Motor unit number index (MUNIX) in myopathic disorders: clinical correlations and potential pitfalls","volume":"49","author":"Gomes de Sousa","year":"2019","journal-title":"Clin Neurophysiol."},{"key":"B41","doi-asserted-by":"publisher","first-page":"2756","DOI":"10.1016\/j.clinph.2016.05.185","article-title":"A dilemma in stroke application: standard or modified motor unit number index?","volume":"127","author":"Zhou","year":"2016","journal-title":"Clin Neurophysiol."}],"container-title":["Frontiers in Neurology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fneur.2021.705816\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,12,21]],"date-time":"2021-12-21T05:24:36Z","timestamp":1640064276000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fneur.2021.705816\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,12,21]]},"references-count":41,"alternative-id":["10.3389\/fneur.2021.705816"],"URL":"https:\/\/doi.org\/10.3389\/fneur.2021.705816","relation":{},"ISSN":["1664-2295"],"issn-type":[{"type":"electronic","value":"1664-2295"}],"subject":[],"published":{"date-parts":[[2021,12,21]]},"article-number":"705816"}}