Sural nerve conduction in mild polyneuropathy.

The motor conduction velocity of the lateral popliteal and tibial nerves as well as the maximal sensory conduction velocity of the sural nerve were measured in 187 patients with signs and symptoms suggestive of mild or early polyneuropathy. The maximal sural conduction velocity gave a high diagnostic yield compared to the motor conduction velocity of the nerves in the legs. In the neuropathies in which the predominant pathological abnormality is known to be axonal degeneration, the maximal sural conduction velocity was often showed in patients with normal motor conduction velocities. The amplitude of the sensory potential did not prove helpful in individual cases because it was often within the normal range.