Digit I – Wrist

Surface Recording Technique, Orthodromic Study
  • Giuliano Gentili
  • Mario Di Napoli

Original Settings

Sensitivity was 5 μV/division and sweep speed was 1 ms/division. Low-frequency filter, high-frequency filter, duration of pulse, rate of pulse, and the machine used were not specified.


This study was performed in the supine position.


Following the orthodromic method [1], sensory nerve action potentials (SNAPs) were recorded at the wrist (Fig. 1). For the median nerve (R1), the active recording electrode was placed proximally to the distal wrist crease; for the radial nerve (R2) the active recording electrode was placed over the superficial radial nerve at the proximal border of the “anatomical snuff box.” The reference electrodes were placed proximally. The ground (G) electrode position was not specified in the report; the figure shows the ground electrode placed on the palm.


Median Nerve Carpal Tunnel Syndrome Ulnar Nerve Radial Nerve Nerve Conduction Study 
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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Giuliano Gentili
    • 1
  • Mario Di Napoli
    • 1
  1. 1.Neurological ServiceS. Camillo de’ Lellis General HospitalRietiItaly

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