Background: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. There are
many additional electrophysiologic methods for diagnosis of CTS. However, these methods give
unpleasant pain to patients and result in rising costs. We analyze routine nerve conduction studies to
improve diagnostic simplification and sensitivity for CTS.
Methods: A total of 70 patients with clinically diagnosed CTS and 207 control subjects were enrolled.
All subjects were examined by routine nerve conduction studies. Normal limits were derived by
calculating the mean±2 standard deviations from the data of the controls. The sensitivity and specificity
of each test were calculated.
Results: The difference between median and ulnar sensory peak latency was the most sensitive
parameter for CTS. The sensitivity and specificity of the median-ulnar sensory latency difference was
59.4% and 96.5% respectively. The patients with 2 or more abnormal findings in 5 newly developed
parameters (difference of motor terminal latency between median and ulnar nerve, difference of
sensory peak latency between median and ulnar nerve, difference of sensory peak latency between
median and radial nerve, difference of F wave latency between median and ulnar nerve and modified
combined sensory index) could be more sensitive for CTS.
Conclusions: In our study, some parameters derived from routine nerve conduction studies, especially
difference between median and ulnar sensory latency, could be more sensitive for diagnosis of CTS.




KEYWORDS
Carpal tunnel syndrome,
Nerve conduction studies,
Median nerve