Noninvasive estimation of motor unit conduction velocity distribution using linear electrode arrays

Determining the conduction velocity of motor unit action potentials is one of the most important problems in surface electromyography. The estimate of one average conduction velocity value depends on a variety of uncontrollab le factors. More meaningful information is obtained from the estimation of the distribution of the different delays in the myoelectric signals. A solu tion to the problem is the separation and characterization of the individua l components propagating at different velocities, ii technique, based on su rface electrode array recording, is proposed to estimate motor unit conduct ion velocity distribution. The method consists in the identification of the single action potentials in the time stale domain (with the continuous wav elet transform) and in the estimation of their conduction velocities based on the beamforming algorithm. Tbe performances of the technique hare been e valuated using simulated and real myoelectric signals, The results demonstr ate that the technique is accurate and reliable. The method mag be useful f or the diagnosis of neuromuscular disorders, for the monitoring of muscle f atigue and for noninvasive investigation of individual motor units.