Welcome to this presentation on the neck, part I. Here, we have the introduction to the lecture
and two areas are highlighted. These happen to be the triangles of the neck. So if you’ll continue
on this journey with me, we’ll learn more about these geometric configurations. So again, two
colored areas here. We have the area in blue. This is one of the major triangles of the neck.
Then the one located posteriorly is the second triangle of the neck. Because of their anatomic
relationships, the one in blue is referred to as the anterior cervical triangle. The muscle that we
see here as a major boundary is the sternocleidomastoid. It will separate this anterior
triangle from the one that lies posterior. That then leads us to this green-colored region
which represents the posterior triangle of the neck. Its posterior boundary is seen right along
here. That represents the trapezius muscle. Each triangle can be divided into smaller parcels
or subdivisions. So when we look at the anterior triangle, this one is more complicated. We can see
this region just inferior to the mandible and bounded by the stylohyoid muscle here and the
anterior belly of the digastric. This area represents your submandibular triangle. Lying inferior
to the anterior belly of the digastric muscle is a small region or triangle called the submental
triangle. Its inferior boundary would be at the level of the hyoid bone that we see here and then
another boundary would be the midline of this particular region. Your third subdivision to the
anterior triangle is your carotid triangle. Here we can see the stylohyoid muscle and here we
see the anterior belly of the omohyoid as well as the sternocleidomastoid forming its boundaries.
The fourth and final subdivision of the anterior triangle is referred to as the muscular triangle.
Its boundaries would be your anterior belly of the omohyoid, the inferior portion of the
sternocleidomastoid. shown here. Then it would run to the midline of the neck. The upper limit
of this area would be your hyoid bone. The posterior triangle is less complex with respect
to its subdivisions. Here, we see the occipital triangle, the posterior triangle identified.
Its boundaries are the sternocleidomastoid. Here, you see the posterior belly of your omohyoid.
Then you see the trapezius. The second and final subdivision of your posterior triangle is the
omoclavicular triangle, this small area here. You can see it’s bounded by the posterior belly
of the omohyoid, hence omo in the prefix. This boundary here is the clavicle, hence clavicular
as the suffix. Then the third and final boundary to this triangle
is going to be your sternocleidomastoid.