[H-reflex in the extensor digitorum brevis muscle: study in the normal subject and in latent alcoholic neuropathies].

A comparative electromyographic study was carried out in normal subjects (group I) and in alcoholics without clinical evidence of polyneuropathy (group II). -The H reflex of the extensor digitorum brevis muscle (E.D.B.), the electromyogram of EDB, the conduction velocity of the fasted motor fibers of the peroneal nerve (PN), the sensory conduction velocity and amplitude of the evoked potential of the cutaneous fibers of PN, the H reflex of the soleus muscle. -Two kinds of changes were observed in group II: --a significant increase in the latent period of H respones in EDB, in particular the latent period of responses provoked by distal stimulation of PN (+25 PER CENT); --A SIGNIFICANT DECREASE IN THE AMPLITUDe of the sensory potential of the PN(--46 per cent). The other parameters studied in group II did not show any significant difference in comparison with the control group. These results indicate that PN is involved early in a complex fashion in latent alcoholic neuropathies. They confirm that the distinction between axonal neuropathy and segmental demyelination is rarely absolute.