[Electrical activity of motor unit action potentials following spinal cord injury]

The author studied the action potentials (AP) duration of the gastrocnemius and the tibial muscles motor units (MU) in patients with the spinal cord trauma by means of local electromyography. The AP duration of the gastrocnemius decreased by 27% on the average, and of the tibial muscle--by 38% in comparison with the normal age values. There was no direct dependence between the reduction of the AP duration of the gastrocnemius and the tibial muscle MU on the spinal cord affection level, the posttraumatic period duration, and the spastic syndrome expression. Changes in the AP duration of the MU were apparently due to different degree of the atrophic process resulting from prolonged adynamia.