A novel method to measure sensory nerve conduction of the supraclavicular nerve.

INTRODUCTION

In this report we describe a reliable method for recording sensory nerve action potentials (SNAPs) of the supraclavicular nerve.

METHODS

Supraclavicular SNAPs were recorded by placing a surface active electrode at the posterior border of the sternocleidomastoid muscle at a distance of 6 cm from the sternoclavicular joint. The nerve was stimulated at the lower border of the clavicle 4.5 cm lateral to the sternoclavicular joint.

RESULTS

Supraclavicular SNAPs were recorded bilaterally from 20 healthy volunteers. Mean onset latency was 1.0 ± 0.2 ms, and mean peak latency was 1.4 ± 0.3 ms. Mean baseline-to-peak amplitude for the SNAPs was 6.1 ± 2.2 µV, and mean maximum conduction velocity was 59.8 ± 6.2 m/s. The mean percentage of side-to-side difference in amplitude was 12.9 ± 11.0%.

CONCLUSIONS

Supraclavicular SNAPs could be obtained in all normal subjects. Assessment of supraclavicular nerve conduction is very useful in the diagnosis of supraclavicular neuropathy.