title: Branched EMG electrodes for stable and selective recording of single motor unit potentials in humans.
abstract: Branched surface EMG electrodes are bipolar electrodes with the hot signal pole referenced to two or more short-circuited leading-off surfaces. This technique provides stable recording of single motor unit potentials during real movements, up to maximal muscle contractions. The selective characteristic of branched electrodes is based on the same principles as the double differential detection system and spatial filtering technique proposed later. Equi-weight calculations to assess the selectivity of different electrode types and their position are used. The main advantage of branched electrodes, especially high stability, is achieved by the wire electrode version. The design, manufacture, implementation, and application of wire electrodes are discussed in detail. During recording of motor unit potentials, electrodes are positioned subcutaneously over the muscle fascia. This positioning maximizes electrode stability. Appropriate orientation of the electrode relative to the muscle architecture ensures adequate selectivity for single motor unit recordings. Branched electrodes require ordinary EMG equipment (two or even one amplifier).
authors.affiliation: Institute of Biophysics, Bulgarian Academy of Sciences, Sofia, Bulgaria.
authors.forename: Lilia
authors.initials: L
authors.lastname: Christova
authors.forename: Diana
authors.initials: D
authors.lastname: Stephanova
authors.forename: Andon
authors.initials: A
authors.lastname: Kossev
mesh_terms: D017076:Computer-Aided Design; D004567:Electrodes, Implanted; D004576:Electromyography / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D008839:Microelectrodes; D009046:Motor Neurons / Q000502:physiology*; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology*; D009431:Neural Conduction / Q000502:physiology; D009469:Neuromuscular Junction / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity