Klinische Neurophysiologie 2017; 48(03): 144-150
DOI: 10.1055/s-0043-115149
Originalia
© Georg Thieme Verlag KG Stuttgart · New York

Update – Neurophysiologische Methoden zur Bestimmung der Anzahl motorischer Einheiten in menschlichen Muskeln

Neurophysiological Methods for Determining the Number of Motor Units in Human Muscles: An Update
Thomas Grimm
1   Neurologische Klinik und Poliklinik der Universität Regensburg, Universitätsklinikum Regensburg
,
Wilhelm J. Schulte-Mattler
1   Neurologische Klinik und Poliklinik der Universität Regensburg, Universitätsklinikum Regensburg
› Author Affiliations
Further Information

Publication History

Publication Date:
26 July 2017 (online)

Zusammenfassung

Die Anzahl funktionstüchtiger motorischer Einheiten stellt nach wie vor das ideale Maß zur Verlaufsbeurteilung bei Erkrankungen mit Verlust motorischer Einheiten dar. Die absolute Zahl motorischer Einheiten (ZME) sowie deren Verlauf über die Zeit erlauben neben der Beschreibung des Krankheitsverlaufes Aussagen über Regenerationsmechanismen wie Reinnervation durch kollaterale Aussprossung oder Reinnervation durch Axonwachstum. Eine exakte Bestimmung der Zahl motorischer Einheiten ist leider auch heute nicht möglich, eine Schätzung funktionstüchtiger motorischer Einheiten hingegen mit elektrophysiologischen Methoden durchführbar. Der apparative und zeitliche Aufwand älterer Methoden zur Schätzung der Anzahl motorischer Einheiten ist außerordentlich hoch und bedarf spezieller Untersucher-Erfahrung. Die 2004 erstbeschriebene Methode MUNIX hingegen ist einfach durchführbar und deutlich weniger zeitaufwendig. MUNIX eignet sich hervorragend zur Verlaufsbeurteilung der ZME bei bekanntem Verlust motorischer Einheiten. Neue Untersuchungen hingegen zeigen, dass MUNIX als diagnostische Methode per se ungeeignet ist.

Abstract

The motor unit number is still the ideal measure for describing disease progression in diseases with loss of motor units. The absolute number of motor units as well as their course over time allow not only the description of disease-progression but also give information about regeneration mechanisms – on the one hand, reinnervation by collateral sprouting, and on the other hand, reinnervation by axon growth. An exact determination of the number of motor units is unfortunately not yet possible, but an estimation of functional motor units can be carried out with electrophysiological methods. Older methods for motor unit number estimation (MUNE) are extremely time consuming and often involve high outlay costs for equipment and investigator experience. The MUNIX method, first described in 2004, is easy to implement and far less time-consuming. MUNIX is very well suited for describing motor unit number loss if motor unit loss is known. However, recent investigations show that MUNIX cannot be used as a diagnostic method per se.

 
  • Literatur

  • 1 Schulte-Mattler W. Neurophysiologische Methoden zur Bestimmung der Anzahl motorischer Einheiten in menschlichen Muskeln. Klin Neurophysiol 2011; 42: 221-225
  • 2 Gooch CL, Doherty TJ, Chan KM. et al. Motor unit number estimation: A technology and literature review. Muscle & nerve 2014; 50: 884-893
  • 3 McComas AJ, Fawcett PR, Campbell MJ. et al. Electrophysiological estimation of the number of motor units within a human muscle. J Neurol Neurosurg Psychiatry 1971; 34: 121-131
  • 4 Kadrie HA, Yates SK, Milner-Brown HS. et al. Multiple point electrical stimulation of ulnar and median nerves. J Neurol Neurosurg Psychiatry 1976; 39: 973-985
  • 5 Wang FC, Delwaide PJ. Number and relative size of thenar motor units estimated by an adapted multiple point stimulation method. Muscle & nerve 1995; 18: 969-979
  • 6 Stashuk DW, Doherty TJ, Kassam A. et al. Motor unit number estimates based on the automated analysis of F-responses. Muscle & nerve 1994; 17: 881-890
  • 7 Daube JR. Estimating the number of motor units in a muscle. Journal of clinical neurophysiology: official publication of the American Electroencephalographic Society 1995; 12: 585-594
  • 8 Bischoff C, Dengler R. Referenzreihe Neurologie EMG - NLG. Thieme; 2014
  • 9 Ridall PG, Pettitt AN, Henderson RD. et al. Motor unit number estimation–a Bayesian approach. Biometrics 2006; 62: 1235-1250
  • 10 Henderson RD, Ridall PG, Hutchinson NM. et al. Bayesian statistical MUNE method. Muscle & nerve 2007; 36: 206-213
  • 11 Brown WF, Strong MJ, Snow R. Methods for estimating numbers of motor units in biceps-brachialis muscles and losses of motor units with aging. Muscle & nerve 1988; 11: 423-432
  • 12 Doherty TJ, Stashuk DW. Decomposition-based quantitative electromyography: methods and initial normative data in five muscles. Muscle & nerve 2003; 28: 204-211
  • 13 Nandedkar SD, Nandedkar DS, Barkhaus PE. et al. Motor unit number index (MUNIX). IEEE transactions on bio-medical engineering 2004; 51: 2209-2211
  • 14 Schulte-Mattler W, Grimm T, Stein F, Kobor I. et al. MUNIX – a promising biomarker in ALS. Klin Neurophysiol 2015; 46: 186-189
  • 15 Stein F, Kobor I, Bogdahn U. et al. Toward the validation of a new method (MUNIX) for motor unit number assessment. Journal of electromyography and kinesiology: official journal of the International Society of Electrophysiological Kinesiology 2016; 27: 73-77
  • 16 Neuwirth C, Nandedkar S, Stalberg E. et al. Motor unit number index (MUNIX): a novel neurophysiological technique to follow disease progression in amyotrophic lateral sclerosis. Muscle & nerve 2010; 42: 379-384
  • 17 Marciniak C, Li X, Zhou P. An examination of motor unit number index in adults with cerebral palsy. Journal of electromyography and kinesiology: official journal of the International Society of Electrophysiological Kinesiology 2015; 25: 444-450
  • 18 Li X, Wang YC, Suresh NL. et al. Motor unit number reductions in paretic muscles of stroke survivors. IEEE transactions on information technology in biomedicine: a publication of the IEEE Engineering in Medicine and Biology Society 2011; 15: 505-512
  • 19 Li X, Liu J, Li S. et al. Examination of hand muscle activation and motor unit indices derived from surface EMG in chronic stroke. IEEE transactions on bio-medical engineering 2014; 61: 2891-2898
  • 20 Nandedkar SD, Barkhaus PE, Stalberg EV. Motor unit number index (MUNIX): principle, method, and findings in healthy subjects and in patients with motor neuron disease. Muscle & nerve 2010; 42: 798-807
  • 21 Neuwirth CW. M Motor Unit Number Index (MUNIX) – ein neuer elektrophysiologischer Marker zur Abschätzung der Anzahl motorischer Einheiten: Eine Literaturübersicht. Klin Neurophysiol 2013; 44: 132-139
  • 22 Furtula J, Johnsen B, Christensen PB. et al. MUNIX and incremental stimulation MUNE in ALS patients and control subjects. Clinical neurophysiology: official journal of the International Federation of Clinical Neurophysiology 2013; 124: 610-618
  • 23 Schulte-Mattler WJ, Georgiadis D, Tietze K. et al. Relation between maximum discharge rates on electromyography and motor unit number estimates. Muscle & nerve 2000; 23: 231-238
  • 24 Henderson RD, McCombe PA. Assessment of motor units in neuromuscular disease. Neurotherapeutics 2016; DOI: 10.1007/s13311-016-0473-z.
  • 25 Boekestein WA, Schelhaas HJ, van Putten MJ. et al. Motor unit number index (MUNIX) versus motor unit number estimation (MUNE): a direct comparison in a longitudinal study of ALS patients. Clinical neurophysiology: official journal of the International Federation of Clinical Neurophysiology 2012; 123: 1644-1649
  • 26 Mitsumoto H, Ulug AM, Pullman SL. et al. Quantitative objective markers for upper and lower motor neuron dysfunction in ALS. Neurology 2007; 68: 1402-1410
  • 27 Daube JR. Motor unit number estimates–from A to Z. J Neurol Sci 2006; 242: 23-35
  • 28 Fukada K, Matsui T, Furuta M. et al. The Motor Unit Number Index of subclinical abnormality in amyotrophic lateral sclerosis. Journal of clinical neurophysiology: official publication of the American Electroencephalographic Society 2016; DOI: 10.1097/WNP.0000000000000296.
  • 29 Escorcio-Bezerra ML, Abrahao A, de Castro I. et al. MUNIX: Reproducibility and clinical correlations in Amyotrophic Lateral Sclerosis. Clinical neurophysiology: official journal of the International Federation of Clinical Neurophysiology 2016; 127: 2979-2984
  • 30 Neuwirth C, Barkhaus PE, Burkhardt C. et al. 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. J Neurol Neurosurg Psychiatry 2015; 86: 1172-1179