Normal EMG

Normal EMG Activity

Volume II - Part I

Objectives
1 - Subjective assesment of MUP waveform and firing rate.
2 - Manual measurements of the MUP and IP.
3 - Correlate EMG waveform with it's sound.
4 - Recognize differences in EMG signals from different normal muscles.

Paraspinal	Normal Insertional Activity (Note the Frequency of Spikes)	Sharp MUP: 1 mV, 10 Hz Many Distant MUPs
Abductor Pollicis Brevis	Complex Waveforms: MUP Superimposition	Full Pattern at Maximal Effort
First Dorsal Interosseus	Simple MUPs: 500 - 2200 uV, 11 Hz	Full Pattern, 4 mV Envelope Amplitude
Extensor Digitorum Communis	MUPs Resembling Positive Sharp Waves	Min - Max Effort 2 Trials at 2 sec/div, 1 mV/div
Biceps Brachii	2 Simple MUPs: 500 - 700 uV, 8 - 10 Hz	Peaks of High/Low Amplitude, Long/Short Duration
Triceps	2 Simple MUPs: 1000-1500 uV, Small Distant MUP	Normal Recruitment Frequency: 10 Hz
	Full IP at Fast Sweep (10 ms/div)	IP at Slow Sweep: 3 Trials: 2 sec/div, 1 mV/div
Deltoid	Serrated MUPs (?) Many Distant MUPs	Maximal Effort, 3 Trials 2 sec/div, 1 mV/div 2 - 3 mV Envelope Amplitude
Gluteus Medius	Several Simple and Complex MUPs	Min to Max Effort 2 Trials: 2 sec/div, 1 mV/div
Vastus Medialis	Simple MUPs Normal Recruitment Frequency (10 Hz)	2 Simple MUPs 300 - 900 uV, 8 - 10 Hz
	Full IP at Fast Sweep (10 ms/div)	Min to Max Effort 2 Trials: 2 sec/div, 1 mV/div
Tibialis Anterior	One Sharp MUP: 500 uV, 8 - 9 Hz Many Distant MUPs	Many Near MUPs: 500 - 1800 uV
	Full IP at Fast Sweep	Normal Amplitude on Slow Sweep Min to Max Effort 2 Trials: 2 sec/div, 1 mV/div
Medial Gastrocnemius	Simple and Polyphasic MUPs
	Full Pattern at Maximal Effort	3 Trials: Min - Max Effort 2 sec/div, 1 mV/div Note Variation in Amplitude
Orbicularis Oris	Small Fast Firing MUP That's Normal	Recruitment of Second MUP
	More Recruitment, Polyphasic MUP
Tongue	Many MUPs: Short, Simple, 200 - 400 uV
	Many MUPs at Maximum Effort Note the Amplitude	EMG at Slow Sweep: Min to Max Effort