High-density surface electromyography to assess motor unit firing rate in Charcot-Marie-Tooth disease type 1A patients

The aim of this study was to elucidate the characteristics motor unit (MU) firing rate in Charcot-Marie-Tooth disease type 1A (CMT1A) patients and its longitudinal change using high-density surface-electromyography (surface-EMG) MU decomposition analysis. Nineteen with CMT1A 21 force-matched healthy controls prospectively underwent surface-EMG recording vastus lateralis muscle during ramp-up sustained contractions on performing isometric knee extension. After analysis, instantaneous rates (IFRs) individually identified MUs were calculated. In patients, follow-up measurements performed one year after baseline. Comparison IFRs clinical variables between at baseline performed. Mean lower than controls. This true various force levels (p < 0.01. e.g., 10.3 (CMT1A patients) vs. 12.2 (controls) pulses-per-second (pps) 22.5–27.5% maximal voluntary contraction (MVC) recruited <7.5% MVC) any time-point 0.001. 8.0 9.3 pps, respectively, 10–20 seconds). mean 0–10 seconds significantly decreased over (from 8.06 7.52 pps; p = 0.027), whereas severity score MVC extension did not time. had a individual rate. is potential short-term biomarker axonal damage patients.