Alcrd. De Oliveira et al., Limitations on the clinical utility of the ulnar dorsal cutaneous sensory nerve action potential, CLIN NEU, 111(7), 2000, pp. 1208-1210
Objective: To validate the clinical use of the ulnar dorsal cutaneous (UDCN
) sensory nerve action potential (SNAP) in the topographical analysis of ul
nar mononeuropathies and in the process of choosing a sensory nerve for bio
psy.
Methods: We surveyed the UDCN SNAP electrophysiological characteristics in
both hands of 97 normal volunteers aged 10-84 years. The nerve was recorded
from the 4th intermetacarpal space with subcutaneous needle electrodes and
percutaneous stimulation was carried out at the wrist.
Results: In agreement with other studies, the mean conduction velocity was
58.6 +/- 6.7 m/s, but the mean and the lower normal value of the amplitude
(32 and 14.7 mu V) were significantly higher than previous known data. An i
mportant finding was that in 21% of our population study, the UDCN SNAP was
absent on at least one side, or significant degree of asymmetry between th
e left and right sides was present.
Conclusion: The UDCN SNAP is technically easy to obtain, but the high frequ
ency of asymmetric or absent potentials detected in this study implies that
caution should be taken in using this SNAP in clinical practice. (C) 2000
Elsevier Science Ireland Ltd. All rights reserved.