Beckenbaugh, Robert D., MD; Peter Simonian, MD: Mayo Clinic, Rochester, MN
Orthopedics, Vol. 18, No. 6: 549-552, June, 1995.

"The conclusive diagnosis of carpal tunnel syndrome (CTS) is aided by electrodiagnostic evaluation. Many physicians do not have easy access to electromyography (EMG) facilities and depend upon less conclusive but suggestive diagnostic clinical tests.

This study evaluated the motor latency values of 72 median nerves assessed with the compact, hand held, battery powered NervePace Electroneurometer. This test performed in the clinical environment in less than five minutes was compared to the results of clinical examination, standard electrodiagnostic tests, and median nerve findings of compression at the time of surgery in 63 patients.

The motor latency values obtained with an electroneurometer positively correlated with those obtained by routine EMG. Electroneurometer and EMG motor latency sensitivity and specificity were calculated for the ability to diagnose CTS. The values of the electroneurometer readings considered to be abnormal in this study were greater than 3.9 milliseconds of motor latency. The test is performed in an exacting manner which stimulates the median nerve 3 cm. proximal to the wrist flexion crease and measure the response of opposition of the thumb by a surface electrode placed over the thenar eminence. This study identified a sensitivity of 85.7% and a specificity of 87.5% in predicting CTS as confirmed by complete EMG and electroconduction studies.

The electroneurometer is an easy to use, office clinical device which can provide the physician with instant specific confirmatory evidence to complete the diagnosis of CTS. It has the additional value of providing assistance to hand surgeons who do not have real access to electrodiagnostic studies, and in selected instances may allow one to eliminate the need for the more sophisticated and expensive testing."