I. Atroshi et R. Johnsson, EVALUATION OF PORTABLE NERVE-CONDUCTION TESTING IN THE DIAGNOSIS OF CARPAL-TUNNEL SYNDROME, The Journal of hand surgery, 21A(4), 1996, pp. 651-654
A portable nerve conduction testing instrument (the electroneurometer)
was investigated to evaluate its sensitivity and specificity in the d
iagnosis of carpal tunnel syndrome. The preoperative electroneurometer
measurements of distal motor and sensory latencies of the median nerv
e in 43 consecutive hands with a dear diagnosis of carpal tunnel syndr
ome (typical history, clinical signs, and complete symptom relief afte
r surgery) were analyzed. Distal motor and sensory latencies of the me
dian nerve were also measured in 60 hands of asymptomatic healthy volu
nteers. The sensitivity of the device in the hands with carpal tunnel
syndrome was 58% for distal motor latency (upper limit of normal, 4.4
ms) and 65% for distal sensory latency (upper limit of normal, 3.5 ms)
. The specificity of the instrument in the control hands was 87% and 9
2% for distal motor and sensory latency, respectively. Receiver operat
ing characteristic curves showed distal sensory latency measurement to
be a superior diagnostic test, with 3.3 ms as optimal upper limit of
normal, giving a sensitivity of 74% and a specificity of 87%. The sens
itivity and specificity of the device are comparable to those reported
for conventional nerve conduction studies.