hello all this is dr. Alsup again and we will be discussing triangles in the anterior neck
now these are constructed subdivisions based on existing anatomical structures that allow better
communication regarding location structures or injuries or pathologies among healthcare teams
so say someone says there's a laceration in the anterior cervical Triangle people
will understand where that is located so it's not so nebulous in terms of describing where
injuries occur also if you have not reviewed the muscle dissection supplement please do
this first as knowing the muscles in this area is important for the boundaries of these triangles
let's get started let's start with the big one before we work on the subdivisions and this is
the anterior cervical triangle you can really see this well outlined here in this image the
boundaries of the anterior cervical triangle include medial most is the midline so kind of
right down the middle here superior most is the base or the bottom of the mandible and lateral
most is going to be the anterior border of your sternocleidomastoid muscle right here so I want
you to take a moment and trace these structures out on yourself you can actually feel or palpate
where all of these boundaries are on yourself that that sternocleidomastoid is that large rope-like
muscle in your neck so take a moment pause the video if you need to and try to kind of visualize
on yourself for this is located once you've done that let's break down the subdivisions of this of
this triangle alright so I want to take a moment and kind of show you where those boundaries were
before so what I'm tracing right here is going to be the anterior cervical triangle so all of
these triangles that we are about to discuss are within the anterior cervical triangle so these
are four subdivisions of the anterior cervical triangle we're going to start superiorly and
move inferior least starting with the submental triangle the boundaries for this triangle include
medially that midline that we talked about laterally is going to be the anterior belly
of the digastric muscle so here is the digastric specifically that anterior belly which you can
see here and inferiorly the boundary is going to be the hyoid so the hyoid bone is right here
so you can see those super hyoid muscles here in the infrahyoid muscles down here so those
are the boundaries of this submental triangle in terms of contents you're gonna have some
super high weight muscles as well as some lymph nodes lateral to the submental triangle is the
submandibular triangle which is sometimes referred to as the digastric triangle and
is sometimes called that the digastric triangle because both bellies of the digastric muscles so
the anterior which we already showed here so the anterior as well as the posterior bellies form the
inferior boundaries you can't see the posterior belly of the digastric very well in this view
because the large submandibular gland is going to be occluding that view the superior boundary
is going to be the mandible so as you can see the submandibular gland is probably the major content
of this triangle as well as the facial artery and the facial vein which you can't see particularly
well here alright moving inferior lis we have the other two triangles which we see over here on the
left side here is the carotid triangles so craw the triangles right here the boundaries of the
carotid triangle include superiorly is going to be the posterior belly of the digastric again
occluded by the slubs large submandibular gland laterally the the boundary will be the SCM again
so that's sternocleidomastoid muscle and medially we're going to have the superior belly of the
omohyoid as the name would suggest the contents of this triangle includes the carotid sheath and
contents you can see the common carotid artery here the internal jugular vein here the ancestor
of a callus specifically that's superior limb there you can't see the vagus nerve here because
it's deep but it would be considered a content of the carotid sheath lastly there is the muscular
triangle which is formed medially by the midline inferior laterally right along this border by the
sternocleidomastoid and superior laterally by the superior belly of the omohyoid muscle as the name
of the triangle would suggests muscles are the major contents here specifically the infrahyoid
muscles but the deeper thyroid gland as well as the larynx would also be considered within the
boundaries of this triangle so a very important subdivision of the anterior cervical triangle
alright so that is the anterior cervical triangle and the four smaller subdivisions take some time
to review these boundaries and consider the contents and after doing so if you have any
questions please don't hesitate to reach out with any questions thank you for your time