An unusual cause of thenar hypertrophy and carpal tunnel syndrome

Comparison of ring versus disposable disk electrodes in recording antidromic sensory median nerve conduction study for diagnosis of carpal tunnel syndrome

PURPOSE

The authors performed a study using disposable disk electrodes, currently used to record motor nerve conduction study, for median antidromic sensory recording from the second digit with the aim of establishing efficiency by using one type of electrode throughout the entire nerve conduction study. This study aims to establish noninferiority with the use of disk electrodes rather than conventionally used nondisposable ring electrodes in the diagnosis of carpal tunnel syndrome.

METHODS

For median sensory response, 4 parameters were studied: (1) onset latency, (2) peak latency, (3) amplitude, and (4) conduction velocity. Ten hands with active disease and 10 control hands without disease were studied via both ring electrodes and disk electrodes. The results were compared between the ring and disk electrodes.

RESULTS

There was no statistically significant difference between the ring electrodes and the disk electrodes in recording the four parameters of the antidromic median sensory nerve conduction study using the second digit.

CONCLUSIONS

Our study indicates that disposable disk electrodes could replace ring electrodes to perform median sensory antidromic nerve conduction studies for the diagnosis of carpal tunnel syndrome. However, further studies need to be carried out with larger sample sizes and for other indications.