The Effect of a Suprascapular Nerve Block on Mean EMG of the Deltoid Muscle

Abstract

Surface electromyography is used in various clinical and research settings to examine the electrical activity of muscles. The objective of our study was to understand how humeral angle and a suprascapular nerve block affected mean EMG of each head of the deltoid muscle. We recruited 7 subjects from the University of Oregon. Our results suggest that a suprascapular nerve block significantly decreased the mean EMG of the anterior head of the deltoid, but had no significant effect on the middle or posterior heads. Our results also suggest that the anterior head of the deltoid significantly decreased as angle increased and with time, but no significant difference was observed in the middle head of the deltoid. However, we did observe a significant decrease in EMG of the posterior head of the deltoid with time, but not with humeral angle change. This study may be a useful guide and resource for future studies involving nerve blocks and EMG.