Digit IV – Wrist

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

Original Settings

Sensitivity was 10 μV/division, low-frequency filter was 10 Hz, high-frequency filter was 2 kHz, and sweep speed was 1 ms/division. 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], the median and ulnar sensory nerve conduction studies were performed. For both the median and ulnar nerves, digit IV to the wrist sensory nerve conduction studies were done orthodromically at the wrist (Fig. 1). For both the median nerve (R1) and the ulnar nerve (R2), the active electrodes (A) were placed proximal to the distal crease at the wrist; the references (R) were placed proximally. For the median nerve (R1), electrodes were placed between the tendons of the flexor carpi radialis (FCR) and the palmaris longus (PL) muscles. For the ulnar nerve (R2), electrodes were placed just lateral to the tendon of the flexor carpi ulnaris(FCU) muscle. Recording...


Onset Latency Median Nerve Ulnar Nerve Latency Difference Median Potential 
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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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