Neurol. praxi. 2026;27(4):268-272 | DOI: 10.36290/neu.2026.047
The role of neurophysiology in the diagnosis of myoclonus
- II. neurologická klinika LF UK a UNB, Bratislava
Myoclonus represents a heterogeneous group of hyperkinetic disorders characterized by sudden, brief muscle jerks. Precise classification according to the generator (cortical, subcortical, spinal, peripheral, or functional) is crucial for both diagnosis and treatment; however, clinical differentiation is often challenging. Diagnosis becomes even more complicated when myoclonus occurs in conjunction with another hyperkinetic disorder, for example in cervical dystonia or in typical or atypical parkinsonian syndromes. Electrophysiological methods, particularly polymyography (poly-EMG), electroencephalography (EEG), somatosensory evoked potentials (SSEP), and jerk-locked back-averaging (JLBA), enable objective assessment and accurate localization of the myoclonus generator. This article provides a practically oriented overview of the electrophysiological diagnosis of myoclonus, with a focus on interpretation of findings, technical aspects of the examinations, and an algorithmic approach applicable in neurological practice.
Keywords: myoclonus, EMG, EEG, SSEP, jerk-locked back-averaging, differential diagnosis.
Received: June 3, 2026; Revised: August 1, 2026; Accepted: August 19, 2026; Published: October 2, 2026 Show citation
References
- Apartis E. Clinical Neurophysiology of Psychogenic Movement Disorders: How to Diagnose Psychogenic Tremor and Myoclonus. Neurophysiologie Clinique = Clinical Neurophysiology. 2014;44(4):417-24. https://doi.org/10.1016/j.neucli.2013.08.014.
Go to original source... 
Go to PubMed... - Apartis E, Vercueil L. To Jerk or Not to Jerk: A Clinical Pathophysiology of Myoclonus. Revue Neurologique. 2016;172(8-9):465-76. https://doi.org/10.1016/j.neurol.2016.07.013. Go to original source... Go to PubMed...
- Apartis E. Clinical Neurophysiology in Movement Disorders. Handbook of Clinical Neurology. 2013;111:87-92. https://doi.org/10.1016/B978-0-444-52891-9.00008-7. Go to original source... Go to PubMed...
- Edwards MJ, Koens LH, Liepert J, et al. Clinical Neurophysiology of Functional Motor Disorders: IFCN Handbook Chapter. Clinical Neurophysiology Practice. 2024;9:69-77. https://doi.org/10.1016/j.cnp.2023.12.006. Go to original source... Go to PubMed...
- Hayes M, Thompson PO. Chapter 39 Psychogenic Movement Disorders. In: Handbook of Clinical Neurophysiology, zv. 1. Elsevier. 2003. [Internet]. Dostupné na: https://doi.org/10.1016/S1567-4231(09)70187-X. Go to original source...
- Latorre A, van der Veen S, Pena A, et al. IAPRD New Consensus Classification of Myoclonus. Parkinsonism & Related Disorders. 2025;13. https://doi.org/10.1016/j.parkreldis.2024.107216. Go to original source... Go to PubMed...
- Minár M. Neurophysiological methods in examination of tremor. Neurologie pro praxi. 2021;21(6):434-38. https://doi.org/10.36290/neu.2020.065. Go to original source...
- Thompson PD, Colebatch JG, Brown P, et al. Voluntary Stimulus-Sensitive Jerks and Jumps Mimicking Myoclonus or Pathological Startle Syndromes. Movement Disorders: Official Journal of the Movement Disorder Society. 1992;7 (3):257-62. https://doi.org/10.1002/mds.870070312. Go to original source...
- Tijssen MA, Thom M, Ellison DW, et al. Cortical Myoclonus and Cerebellar Pathology. Neurology. 2000;54(6):1350-56. https://doi.org/10.1212/wnl.54.6.1350. Go to original source... Go to PubMed...