NERVE CONDUCTION STUDIESPractical Guide and Diagnostic Protocols

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NERVE CONDUCTION STUDIES

Practical Guide and Diagnostic Protocols

Table of Contents

Title Page ................................................................................................................................................................... 2

Biography .................................................................................................................................................................. 3

Dedication ................................................................................................................................................................. 4

Chapter 1 ................................................................................................................................................................... 5 Definitions

Chapter 2 ................................................................................................................................................................... 6 Basic Anatomy and Physiology of the Peripheral Nervous System

Chapter 3 .................................................................................................................................................................. 10 Principles of Nerve Conduction Studies

Chapter 4 ................................................................................................................................................................... 16 Errors, Pitfalls and Anomalies in Nerve Conduction Studies

Chapter 5 ................................................................................................................................................................... 21 Pathophysiology and Abnormal Findings of Nerve Conduction Studies

Chapter 6 ................................................................................................................................................................... 25 Nerve Conduction Studies Techniques

Chapter 7 ................................................................................................................................................................... 63 Diagnostic Utilities of Nerve Conduction Studies

Chapter 8 ................................................................................................................................................................... 68 Electrodiagnostic Study Protocols

Chapter 9 ................................................................................................................................................................... 78 Repetitive Nerve Stimulation

Appendix 1 ................................................................................................................................................................ 81 Instrumentation

Appendix 2 ................................................................................................................................................................ 82 Safety Protocols

Appendix 3 ................................................................................................................................................................ 83 EMG Laboratory Workflow

Appendix 4 ................................................................................................................................................................ 86 EMG Laboratory Examination Room Set-Up Guide

Appendix 5 ................................................................................................................................................................ 88 Introduction to Needle Electromyography

Appendix 6 ................................................................................................................................................................ 90 Commonly Studied Limb Muscles and Their Innervation

Bibliography ............................................................................................................................................................... 95

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Chapter 6Nerve Conduction Studies Techniques

Median Sensory Nerve (index, middle and thumb)………………………..………………........................................28, 29 & 30 Ulnar Sensory Nerve (antidromic)……………………………….……………………………………………………………………………………….31 Dorsal Ulnar Sensory Nerve (antidromic)…………………………….……………………………………………………………………………….32 Radial Sensory Nerve (antidromic)….……………………………………………………………………………………………………………………33 Median Sensory Nerve (ring finger)………….………………………………………………………………………………………………………….34 Ulnar Sensory Nerve (ring finger)……..………………………………………………………………………………………………………………….35 Median and Ulnar Palmar Mixed Nerve (orthodromic)..……………………………………………………………………….……..36 & 37 Lateral Antebrachial Cutaneous Sensory Nerve (antidromic)……..…………………………………………………………………………38 Medial Antebrachial Cutaneous Sensory Nerve (antidromic)………………………………………………..………………………………39 Median Motor Nerve (APB)…..………………………………………………………………………………………………………………………………40 Ulnar Motor Nerve (ADM and FDI)……………………………………………………………………………………………………….………41 & 42 Median and Ulnar Motor Comparison (2nd Lumbrical/Interossei)…………..……………………………………………………………..43 Radial Motor Nerve (EDC)……………………………………………….…………………………………………………………………………………….44 Musculocutaneous Motor Nerve (Biceps)………………………………………………………………………………………………………………45 Axillary Motor Nerve (Deltoid)……………………………………………………………………………………………………………………………….46 Spinal Accessory Motor Nerve (Trapezius)……………………………………………………………………………………………………………..47 Sural Sensory Nerve (antidromic)…………………………………………………………………………………………………………………………..48 Superficial Peroneal Sensory Nerve (antidromic)……………………………………………………………………………………………………49 Saphenous Sensory Nerve (lower leg)…………………………………………………………………………………………………………………….50 Lateral Femoral Cutaneous Sensory Nerve (thigh)………………………………………………………………………………………………….51 Medial and Lateral Plantar Mixed Nerves (orthodromic)……………………………………………………………………………………….52 Peroneal Motor Nerve (EDB and TA)……………………………………………………………………………………….…….………53 & 54 Tibial Motor Nerve (AH and ADQP)…………………………………………………………………………………………………….…………55 & 56 Femoral Motor Nerve (Rec Fem)……………………………………………………………………………………………………………………………57 H-Reflex (Soleus)……………………………………………………………………………………………………………………………………………………58 Phrenic Motor Nerve (Diaphragm)…………………………………………………………………………………………………………………………59 Facial Motor Nerve (Orbicularis Oculi)……………………………………………………………………………………………………………………60 Blink Reflexes (Orbicularis Oculi)……………………………………………………………………………………………………………………………61 F Waves.………………………………………………………………………………………………………………………………………………………………62 Repetitive Nerve Stimulations for Myasthenia Gravis, Lambert-Eaton Syndrome and Botulism………….……………63 & 64

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Median Sensory Nerve - index (antidromic)

Origin: C6-C7 roots, upper and middle trunk and lateral cord of the brachial plexus, median nerve

Recording Site (G1): Index finger

Reference Site (G2): Index finger

Ground: Palm or top of hand

Stimulation Site: Wrist

Procedure: The recording electrode is placed on the proximal phalanx of the index finger. The reference electrode is placed on the middle phalanx of the index finger. A distance of 13 cm is measured from G1 to the distal wrist crease over the median nerve. The nerve is stimulated at the wrist, proximal to the wrist crease and between the flexor carpi radialis and palmaris longus tendons. The nerve can also be stimulated at the elbow (above the elbow crease, medial to the brachial artery pulse or biceps tendon).

This study can also be performed orthodromically. A bar electrode is placed over the wrist site, with the recording electrode distal. The finger electrodes are connected to the stimulator with the former “G1” electrode acting as the cathode and the “G2” electrode acting as the anode.