[Findings in the peripheral motor system following stimulation of the motor nerve roots: polyradiculitis, amyotrophic lateral sclerosis and polyneuropathy].

The peripheral nervous system was stimulated over the vertebral column by brief, high-voltage condenser discharges. Potentials from proximal and distal muscles were recorded. We examined healthy subjects (N = 28), patients suffering from ALS (N = 5), from polyradiculitis (N = 6), and polyneuropathies (N = 8). In ALS latencies were slightly (in most cases less than 20%), in polyradiculitis latencies were markedly increased (30-40% on average). The latencies of patients suffering from polyneuropathies showed a variable pattern of vulnerability. Moreover, we could show that this method is frequently capable to quantify deficits in the peripheral nervous system when F-waves are absent.