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Palm to Finger Ulnar Sensory Nerve Conduction
Eduardo Davidowich1, Osvaldo J M Nascimento1, Marco Orsini1
1Antônio Pedro University Hospital, Fluminense Federal University , Niterói.
Neurology International
|January 21, 2016
Summary
Diagnosing ulnar neuropathy at the wrist (UNW) is difficult. A simplified sensory nerve conduction (SNC) technique in the wrist and palm improved diagnosis accuracy for type III UNW.
Area of Science:
- Neurology
- Neurophysiology
Background:
- Ulnar neuropathy at the wrist (UNW) presents diagnostic challenges, particularly in localization.
- Current diagnostic methods often require increased sensitivity and specificity.
Purpose of the Study:
- To present a modified and simplified sensory nerve conduction (SNC) technique for the ulnar nerve (UN) in the wrist and palm segments.
- To demonstrate the validity of this technique in diagnosing type III UNW.
Main Methods:
- Antidromic SNC of the UN using fifth finger ring recording electrodes.
- Stimulation of the UN at two points: 14 cm and 7 cm proximal to the active electrode.
- Comparison of amplitude and conduction velocity (CV) ratios between palm-to-finger and wrist-to-finger segments.
Main Results:
- Established normal amplitude ratios (1.4 to 0.76) and CV ratios (0.8 to 1.23) for palm-to-finger and wrist-to-finger segments.
- Identified abnormal SNAP amplitude ratios or significant slowing of UN sensory fibers across the wrist in all 5 patients with type III UNW.
Conclusions:
- The modified and simplified SNC technique is effective in diagnosing type III UNW.
- This method provides valuable electrophysiological evidence for UNW, aiding in localization and diagnosis.
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