Nerve conduction studies and electromyographic findings are valuable in the diagnosis and confirmation of polyneuritis that affect the myeline sheath and axon of peripheral nerve.

The present study was performed in 16 patients with polyneuritis (14 males and 2 females), ranging in age from 10 to 59 years.

Sensory and motor nerve conduction velocities had been studied in peroneal, tibial, median and ulnar nerve.

Electromyographic study was performed on the muscles of upper and lower extremities.

The results obtained were summarized as follows:

1. Delayed velocity, no conduction or diminished amplitude of evoked action potentials in motor nerve conduction studies were observed in 76.7% of peroneal nerve, 66.7% of tibial nerve, 74.1% of median nerve and 81.5% of ulnar nerve. Order of involved nerves was ulnar nerve, peroneal nerve, median nerve and tibial nerve.

2. Delayed velocity or no conduction in sensory nerve conduction studies observed in 74.2% of peroneal nerve, 69.0% of tibial nerve, 44.4% of median nerve and 34.6% of ulnar nerve. Order of invovled nerves was peroneal nerve, median nerve and ulnar nerve.

3. On electromyographic examinations, fibrillation potentials and positive sharp waves were found in 15 of 20 cases (75.0%), increased polyphasic potentials in 15 of 20 cases (75.0%) and decreased number or no motor unit in 19 of 20 cases (95.0%).