Introduction: Many techniques and tests are utilized when attempting to evaluate possible carpal tunnel syndrome (CTS), but few seem to have stirred as much controversy as the second lumbrical-interossei examination (2L-INT). In an attempt to shed light on these incongruities among researchers, a study of the test utilizing a new method was completed on normal subjects. Methods: Sixty-three normals subjects (103 hands), meeting inclusion criteria were tested using the recognized 2L-INT examination, although a different method was used for establishing recording electrode placement. This data set was analyzed for statistical similarity to standard tests used for electrophysiologic evaluation of carpal tunnel syndrome. Results: Results of testing are as follows: mean 2L-INT delta, standard deviation, 95% confidence interval, t-test 3.09 to 5.89 with a critical value of 2.093 comparing 2L-INT to standard tests. ANOVA for age group variance at 0.05 significance level, Calculated F=1.34 with a critical F=2.46. Summary and Conclusion: This data set suggests that among normals, the 2L-INT method showed no statistical similarity to standard nerve conduction tests. There was no age decrement when using the 2L-INT examination, though the high mean and high standard deviation also indicate that the acceptable range is too wide for use as a sensitive indicator of carpal tunnel syndrome. This data set is on parity with a number of researchers who have concluded that this exam suffers from many variables that may effect its reliability. Other standardized testing techniques may be nedded to make this test reliable and sensitive in the evaluation of carpal tunnel syndrome.
