Sensory nerve action postentials(SNAP) of median nerve and ulnar nerve were examined antidromically with ring electrode recording at the ring finger and stimulation at the wrist(distance 12cm) in 39 healthy adults(23 male, 14 female) and were compared according to distal latency, amplitude, duration of SNAP, respectively.

The results were as follows;

1) The mean values of distal latency of median/ulnar SNAP were 2.75 ⁑ 0.23 msec / 2.71 ⁑ 0.24 msec with no significant difference between the two nerves(P>0.05).

2) The mean values of amplitude of median/ulnar SNAP were 57.08 ⁑ 17.60 ㎶ / 44.58 ⁑ 21.14 ㎶ with significant difference between the two nerves(P<0.0001).

3)The mean values of duration of median/ulnar SNAP were 1.36 ⁑ 0.26 ⁑ / 1.37 ⁑ 0.22 msec with no significant difference between the two nerves(P>0.05).

4) The difference of distal latencies between median/ulnar SNAP was 0.14 ⁑ 0.15 msec

Keywords :Median and ulnar SNAP, Difference of distal latency