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Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
Ulnar nerve at the elbow - normative nerve conduction study.
Edvard Ehler1, Petr Ridzoň, Pavel Urban
1Department of Neurology, Regional Hospital and Faculty of Health Studies, University of Pardubice, 44 Kyjevská, 532 03, Pardubice, Czech Republic. edvard.ehler@nemocnice-pardubice.cz.
Journal of Brachial Plexus and Peripheral Nerve Injury
|February 13, 2013
Summary
This study generated reliable reference data for ulnar nerve conduction studies (NCSs) across the elbow in healthy subjects. Results show comparable motor NCSs of the ulnar nerve above and below the elbow.
Area of Science:
- Neuroscience
- Clinical Electrophysiology
Background:
- Establishing normative data for nerve conduction studies (NCSs) is crucial for accurate diagnosis.
- The ulnar nerve's conduction across the elbow is a common site for entrapment neuropathies.
Purpose of the Study:
- To establish reliable reference data for ulnar nerve NCSs across the elbow.
- To assess the comparability of NCSs using different recording muscles in a large cohort.
Main Methods:
- Nerve conduction studies (NCSs) of the ulnar nerve were performed in 227 healthy volunteers.
- Elbows were flexed at 90 degrees, with motor responses recorded from abductor digiti minimi (ADM) and first dorsal interosseous (FDI) muscles.
Main Results:
- Mean Compound Muscle Action Potential (CMAP) amplitude at the wrist for ADM was 9.6 ± 2.3 mV.
- Mean motor nerve conduction velocity (MNCV) in the forearm was 60.4 ± 5.2 m/s.
- Mean MNCV across the elbow was 57.1 ± 5.9 m/s.
Conclusions:
- Motor NCSs of the ulnar nerve above elbow (AE) and below elbow (BE) yield comparable results.
- Methodology recommended by the American Academy of Neuromuscular & Electrodiagnostic Medicine (AANEM) provides reliable data for FDI and ADM.
- This study provides valuable reference data for clinical NCS assessments of the ulnar nerve.
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