Anatomy of the muscles of the larynx, throat, pharynx and lambdoid bone

The larynx is a cartilaginous organ created as a voice instrument. It consists of three cartilages. One of them is cartilage, which is felt to the touch and visible in front of the throat, under the chin, and it is called thyroid cartilage, because it is concave from the inside and curved from the outside, so it looks like a leather shield and some wooden shields. The second cartilage is located behind the first, near the neck, and is connected to the first. He is known as the nameless one. The third cartilage covers the first two. It adjoins the innominate cartilage and approaches the thyroid cartilage without adjoining it. Between the thyroid and innominate cartilages there is a double articulation with two fossae, in which two processes from the innominate cartilage are located, connected to the fossae by means of ligaments. The third cartilage is called "lid cartilage" or "cup cartilage." As the thyroid cartilage approaches the innominate cartilage and moves away from each other, the larynx expands and narrows, and when the cup-shaped cartilage covers the thyroid cartilage and adjoins it or moves away from it, the larynx opens or closes.

Near and in front of the larynx there is a triangular bone, which is called the lambdoid bone, using its symbol lama in Greek writing, that is, lambda, for its shape is as follows: A. The usefulness of creating this bone is that it is a place of exit and support, where do the fibers of the laryngeal muscles grow?

The larynx needs muscles that press the thyroid cartilage to the innominate cartilage, and other muscles that press and superimpose the cup-shaped cartilage on the thyroid, as well as muscles that move the cup-shaped cartilage away from the other two cartilages so that the larynx opens.

Of the muscles that open the larynx, one pair grows from the lambdoid bone, approaches the anterior part of the thyroid cartilage and merges with it, spreading on it. By contracting, these muscles push the cup-shaped cartilage forward upward, so that the larynx expands. Another pair of muscles is classified as the muscles of the throat that pull down, but we believe that it is better classified as muscles common to the larynx and throat. These two muscles extend from the middle of the sternum towards the thyroid cartilage, and in many animals they are accompanied by another pair of muscles.

Further, there are two more pairs of muscles in the larynx. In one of them, both muscles approach the cup-shaped cartilage from behind and merge with it. By contracting, they lift the cup-shaped cartilage and pull it back; then it stops pressing against the thyroid cartilage and the larynx expands. The muscles of the other pair approach the edges of the cup-shaped cartilage; when they contract, they move it away from the thyroid cartilage and stretch it in width; this helps to expand the larynx.

As for the muscles that compress the larynx, one pair of them comes from the side of the lambdoid bone and reaches the thyroid cartilage, then it expands and wraps around the innominate cartilage, so that the ends of both muscles of this pair converge behind the innominate cartilage. When this pair of muscles contracts, it narrows the lower part of the larynx.

Four more muscles of the larynx are sometimes counted as two Double muscles. They connect the ends of the thyroid and innominate cartilages and, contracting, compress the bottom of the larynx. Some believe that one of these pairs lies inside and the other outside.

The muscles that close the larynx are best located when they are created inside the larynx, so that when they contract, they pull the cup-shaped cartilage down and close the larynx with it. Thus, they are created in the form of a pair of muscles emerging from the root of the thyroid cartilage, which rise from the inside on the right to the edges of the cup-shaped cartilage and to the root of the innominate. By contracting, they strengthen the articulation and close the larynx, opposing the muscles of the chest and the abdominal barrier when holding the breath.

These muscles are created small so as not to compress the insides of the larynx, and strong, so that their strength can compensate for the damage caused by their small size when they have to close the larynx and forcefully hold their breath. Their path is straight upward, with a slight deviation, due to which the thyroid and innominate cartilages are connected. Sometimes there are two more muscles in the larynx, located under the cup-shaped cartilage, which help the mentioned pair of muscles.

As for the throat as a whole, the throat has two pairs of muscles that pull down. One of these pairs is the one we mentioned in the section on the larynx, and the other pair also grows from the sternum. It rises and reaches the lambdoid bone and then the throat, which it pulls down.

The muscles of the pharynx are two muscles of the pharynx. These muscles are located at the pharynx and help with swallowing.

As for the lambdoid bone, it has muscles that are unique to it, and muscles that are common to another organ. There are three pairs of muscles unique to the lambdoid bone. One of them comes from the sides of the jaws and reaches a straight line on this bone. This pair of muscles pulls the lambdoid bone towards the jaws. Another pair grows from under the chin and passes under the tongue to the upper edge of this bone; it also pulls the lambdoid bone towards the jaws. The third pair, growing from the sagittal processes located near the ears, is adjacent to the lower end of the straight line present on the lambdoid bone. As for the muscle that is common to another organ, we have already talked about it and will talk about it again.