Vibrometry in carpal tunnel syndrome: correlations with electrodiagnositic parameters and disease severity.

OBJECTIVE

Find correlations among vibratory parameter, electrodiagnostic study, and severity in carpal tunnel syndrome (CTS).

MATERIAL AND METHOD

The hands of 87 patients were grouped according to severity, no CTS, mild, moderate, or severe CTS. Single-frequency (100 Hz) vibrometry and conventional nerve conduction studies (NCS) were tested Vibratory parameters included threshold of digit 1 (VTI), threshold of digit 2 (VT2), threshold difference of digit 1-5 (VTD1-5) and threshold difference of digit 2-5 (VTD2-5). The correlations were found among the data; vibratory parameters obtained from 'mild CTS' and 'no CTS' groups were compared.

RESULTS

All vibratory parameters were inversely correlated with sensory nerve action potential amplitude of median distribution at low level. VTD2-5 also correlated with median distal sensory latency, median-ulnar latencies difference, and median-radial latencies difference at low level. The correlations of disease severity and vibratory testing were between 0.422-0.617 (p < 0.001). There were no significant differences between vibratory parameters of 'mild CTS' and 'no CTS 'groups.

CONCLUSION

Vibratoryparameters have low level of correlation with NCS but low to moderate magnitude of correlation with severity of CTS.