Digit III – Palm, Digit III – Wrist

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

Original Settings

Sensitivity was 20 μV/division, low-frequency filter was 10 Hz, high-frequency filter was 5 kHz, sweep speed was 2 ms/division, duration of pulse was 0.1 ms (0.05 for digit III to reduce stimulus artifact), and the machine used was a Medelec Sapphire 4ME. Rate of pulse was not specified.


This study was performed in the supine position, with the hands and forearms placed on an arm support with the wrist in a neutral position and the digits relaxed.


Following the orthodromic method [ 1], the sensory nerve action potentials (SNAPs) were recorded using recording electrodes mounted on a plastic bipolar bar, placed on the palm and wrist (Fig. 1). The interelectrode distance was 10 mm and the active electrode (A) was in the distal position; the reference (R) was placed proximally. Ground (G) electrode was attached to the distal region of the wrist (on the distal wrist crease).


Digital Palmar Wrist Carpal Tunnel Syndrome (CTS) Normal Hand Pathological Values 
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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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