Next, identify the boundaries of the muscular triangle. The medial, boundary is the midline of the neck below the hyoid bone. The lateral, boundary is the superior belly of omohyoid muscle. The inferior, boundary is the lower anterior portion of the sternocleidomastoid muscle.
The muscular triangle contains the following infrahyoid (or strap) muscles:
These strap muscles are named for their attachments and are all innervated by branches of the ansa cervicalis which arises
from the cervical plexus.
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