The suprascapular nerve arises from the upper trunk of the brachial plexus (C5 and C6). The upper trunk division almost looks like a trifurcation with the suprascapular nerve, posterior division , and then anterior division arranged from cranial to caudal, respectively. It travels posteriorly towards the suprascapular notch , which it enters underneath the suprascapular ligament , which separates the nerve from the suprascapular artery . Occasionally, the suprascapular ligament is completely ossified transforming the notch into a foramen. The nerve then travels deep to the supraspinatus , which it supplies, and then through the spinoglenoid notch to the undersurface of the infraspinatus , which it also supplies.
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