Motor Unit Potential Analysis

Volume II - Part III

Objectives
Tutorial
Workshop


Motor Unit Potential Basics


Generation

Measurements

Technique of Recording/Measurement


Manual

Amplitude Trigger and Delay Line

Multi Motor Unit Analysis/Decomposition

Assessment Strategies


Patterns of Abnormality

Assessment: Mean Values

Assessment: Individual MUP

MUP Amplitude


Normal

Increased

Reduced

Phases and Turns


Normal

Increased

MUP Duration


Normal

Increased

Reduced

MUP and SFEMG


Stable

Unstable

Interpretation of Stability

Monopolar Needle


Recording Territory

Motor Unit Changes in Neuropathy


Disease Processes

Two Normal Motor Units

Loss of Motor Unit

Few Weeks Later

Few Months Later

Few Years Later

New Weakness: MU Fractination

New Onset: Loss of Reinnervated MU

Severe Trauma to Nerve


Loss of Most Motor Units

Regeneration of Motor Units

Myopathy


Disease Processes

Normal Motor Unit

Short Simple MUP

Tall Thin MUP

Complex Long Duration MUP

Neuromuscular Junction Diseases


NMJ Disease

Examples of Normal MUPs


Multi MU Analysis

Simple

Serrations

Polyphasic

Stable: Filters 500 - 10,000 Hz

Examples from Patients with Neuropathy


Multi Motor Unit Analysis

Long Polyphasic

Unstable MUP

Giant, Fast Firing

"Jiggle" With Late Component

Neurogenic Jitter and Block

Low Amplitude Unstable MUP

Examples from Patients with Myopathy


Multi MUP Analysis

Short and Simple

Short Polyphasic

Long Polyphasic

Tall and Thin


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