Terminal latency index in the carpal tunnel syndrome.

Our retrospective study assessed the validity of the median motor terminal latency index (m-TLI) in evaluation of carpal tunnel syndrome (CTS). In patients deemed most likely to have CTS, the mean m-TLI was markedly reduced at 0.25 while the controls had a mean m-TLI of 0.44. The m-TLI was abnormal in all of the "probable CTS" hands and in none of the control hands. The m-TLI is a sensitive adjunctive electrophysiologic measure for the presence of CTS.