Digit III – Wrist to Palm

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

Original Settings

Sensitivity was 20 μV/division, low-frequency filter was 20 Hz, high-frequency filter was 2 kHz, sweep speed was 0.5 ms/division, duration of pulse was 0.2 ms, and the machine used was a Dantec Cantata. Rate of pulse was not specified.


This study was performed in the supine position. The forearm, wrist, and hand were stabilized with Velcro on a comfortable board.


Following the orthodromic method [ 1], the inching test was performed on sensory fibers of the median nerve in digit III (Fig. 1). Five sensory nerve action potentials (SNAPs) were recorded, with a bipolar fixed distance (2.2 cm) surface electrode (similar to that used for stimulation) moved in step of 2 cm from a point 2 cm proximal to the distal wrist crease to a point 6 cm distal to this crease (R1–R5). The proximal point (R1) was distal from the stimulating cathode (−) placed at digit III, proximal to the inferior palmar wrist crease. The distal point (R5) was proximal to the...


  1. 1.
    Seror P (2001) Simplified orthodromic inching test in mild carpal tunnel syndrome. Muscle Nerve 24:1595–1600PubMedCrossRefGoogle Scholar
  2. 2.
    Bland JDP (2000) A neurophysiological grading scale for carpal tunnel syndrome. Muscle Nerve 23:1280–1283PubMedCrossRefGoogle Scholar

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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