Basic knowledge of the anatomy of the neck muscles will be useful to anyone who wants to pump up these muscles and not face injuries.
The muscles of the neck perform several functions. First, these muscles control the movements of the head. Secondly, the neck muscles help stabilize the cervical spine. Thirdly, the muscles of the neck cover very important large vessels of the neck and nerve trunks.
In normal anatomy, it is customary to divide the muscles of the neck into three groups according to their location.
Surface (outer) Layer
Here we see only two muscles – they are very different from each other. However, we can see both of these muscles on a living person with the naked eye.
- Subcutaneous muscle of the neck (platysma)
This is a long, thin, unpaired muscle that covers the front of the neck like a piece of wide tissue. The subcutaneous muscle of the neck starts from the fascia of the chest, then it spreads over the collarbone, covers the entire neck in front and is attached to the body of the lower jaw and is woven into the masticatory fascia.
The subcutaneous muscle is involved in lowering the lower jaw and corners of the mouth. You can see the subcutaneous muscle of the neck at work during a very characteristic grimace: - Sternocleidomastoid muscle
This is a paired, large and powerful muscle. It starts with two legs – from the sternum and the sternal end of the clavicle, then goes up, and is attached to the mastoid process of the temporal bone. The sternocleidomastoid muscle contours well under the skin even with slight head movements.
This muscle during work is involved in turning the head, and also tilts the head in a very characteristic gesture for animals when they seek to see or understand something better.
Middle Layer
Nearly all of the muscles in this layer either begin or insert on the hyoid bone, a small, unpaired, horseshoe-like bone located just below the lower jaw. The movements of this bone aid in swallowing, breathing, and chewing. Therefore, almost all the muscles of this layer will directly or indirectly perform these functions. We will focus on the exception to this rule.
For greater convenience, we will first analyze the muscles of the middle layer, which are above the hyoid bone, and then those that are below the hyoid bone.
Above the hyoid bone:
- Geniohyoid muscle
The fibers of this muscle start from the lower jaw, and are attached to the hyoid bone. It is easily palpable as it forms the floor of the mouth. - Digastric muscle
This is a paired, unusual muscle that resembles an obtuse angle. The anterior abdomen starts from the lower jaw, the posterior from the temporal bone. Both bellies are attached to the hyoid bone. - Jaw-hyoid muscle
Here we see a paired, deeply located muscle, which takes part in the formation of the floor of the oral cavity. This muscle starts from the lower jaw, is attached to the hyoid bone. - Stylohyoid muscle
A very thin muscle that can only be seen during surgery or a CT scan. Originates from the styloid process of the temporal bone, inserts on the hyoid bone
Under the hyoid bone:
- Scapular-hyoid muscle
This is the longest muscle of the entire group, which starts from the hyoid bone, then spreads through the lateral region of the neck, goes towards the back and is attached to the upper edge of the scapula. Some of the fibers of this muscle are hidden by a powerful sternocleidomastoid muscle. - Sternohyoid muscle
The handle of the sternum begins, attaches to the hyoid bone. This is a long, wide muscle located vertically. It is often impossible to see it because of the large sternocleidomastoid muscle. - Sternothyroid muscle
This is an even deeper located vertical muscle. It starts from the sternum and attaches to the thyroid cartilage, setting it in motion when swallowing or taking a deep breath. This is the only muscle of the group that is not directly connected to the hyoid bone. - Shytohyoid muscle
Here you can see a very short and inconspicuous muscle that connects the thyroid cartilage and the hyoid bone. This is the smallest muscle of the entire group.