Muscles of the neck: types, location, characteristics and functions.

A summary of the different muscles of the neck, classified and described.

The human locomotor system is a true work of art at the biomechanical level, as muscles, bones and joints work together in order to obtain the greatest range of motion and functionality with the aim of obtaining the greatest range of motion and functionality at the lowest possible cost. Our osteoarticular system is composed of 206 bones, 360 joints and more than 600 skeletal muscles, which allow voluntary movement of the limbs and head.

The skeleton, for its part, is composed of two different sections: the axial and the appendicular. The axial skeletal system consists of 80 bones that define the central human axis, i.e., the skull, the auditory bones, the hyoid, the rib cage, the sternum and the spine. On the other hand, the appendicular skeleton is composed of 26 different bones, which define the anatomy and functionality of our limbs.

Beyond the skeletal system, the muscular system reports an unusual variability. Normally, within the locomotor segment, we only include the striated musculature: that which is controlled voluntarily. Therefore, in this topic we leave out visceral muscles and cardiac muscles, for example, since they move without the human being being being fully aware of it.

The face and neck are some of the most complex muscular subsystems of the human being, since they allow us from communication to swallowing and breathing, that is, everything that defines us both as individuals and as a species. In honor of this intricate system, today we tell you all about the muscles of the neck and their particularities..

The neck and its functions

On a physiological level, the neck is nothing more than the junction point between the head and the trunk. This structure is home to the proximal esophagus, trachea, thyroid gland and parathyroid glands.It also serves as a nerve and Blood highway for all the necessary nutrients and information to reach the brain.

It is an integral part of the human organism and stands out for its complexity, as it presents many different planes and compartments.

The functionality of the neck can be divided into different fronts and facets. These are as follows:

• Digestive: in the neck swallowing occurs, or what is the same, the passage of food from the mouth to the stomach. The esophagus functions as an intermediate pathway.
• Phonatory: the vocal cords, considered the heart of human phonation, are located in the neck. The vibration of these cords allows us to emit sounds.
• Respiratory: from the larynx to the bronchi, the trachea extends in order to give us free passage for gas exchange with the environment.
• Auditory: muscular tension in the neck can translate into hearing problems, as the otic structures are closely related to the neck.
• Hormonal: the thyroid is located in the neck. This glandular structure controls the heart rate, intervenes in the glucose metabolism, maintains the body temperature and many other things.

As you can see, the neck is essential for human survival, physiologically, hormonally and anatomically.. Without this connecting bridge, it would be impossible to communicate the nerve organization center (the brain) with the rest of the body (trunk and extremities).

The most important neck muscles

The structures of the neck are divided into three different and well-differentiated planes: the vertebral, the visceral and the vascular compartments. At the muscular level, three well-differentiated functional groups can be detected. Let us see what they are.

1. Anterior triangle

This section is defined by the anterior border of the sternocleidomastoid muscle, the lower limit of the mandible and the midline of the neck proper. As the name suggests, these muscle groups cover the anterior aspect of the neck, these muscle groups cover the anterior aspect of the neck, that is, what is detected when looking "straight ahead" at a human being.. In turn, the anterior triangle is divided into several subsections.

1.1 Superficial muscles

These are the most externally located. Among them, the sternocleidomastoid muscle, located from the sternal manubrium and the medial third of the clavicle to the mastoid process and the superior nuchal line, stands out.. Its functions include contralateral rotation of the head, homolateral tilt and flexion of the neck.

1.2 Suprahyoid muscles

As the name suggests, this muscle group is located above the hyoid bone and connects it to the skull. As a group, they support the hyoid and are the muscle mass of the floor of the mouth, allowing us to speak, swallow and breathe, among many other things.among many other things.

This group includes the following components: sternohyoid muscle, geniohyoid muscle, mylohyoid muscle, and the anterior and posterior portions of the digastric muscle.

1.3 Infrahyoid muscles

The other side of the coin, i.e., the muscle sections located below the hyoid bone. There are 4 pairs of muscles in the form of powerful bands located in the anterior part of the neck.They respond to the following designations: the sternocleidohyoid muscle, sternothyroid muscle, thyrohyoid muscle and omohyoid muscle.

As we have said, these are not just one muscle, but we have two of each, one in each "half" of the sagittal plane of the neck. These muscles have different origins and insertions, but their function is unique: to mobilize the hyoid in various directions.

2. Lateral muscles

The lateral muscles are easily palpable, so we encourage you to do the test yourself when it comes to locating them. They are composed of three pairs of muscles: the anterior, middle and posterior scalene muscles.. They originate from the cervical vertebrae CII to CVII, and find their insertion point on ribs 1 and 2.

As you can imagine, the main function of these muscle pairs is to elevate the first rib and, in addition, they allow us to tilt the head to the same side: if you tilt the neck to the left side, you can feel the tension of the scalenes on the right side (and vice versa). They are also essential in the inspiration process.

3. Posterior triangle

The posterior section of the neck muscles is composed of those muscle groups that connect the skull to the spine and shoulder girdle (scapulae and clavicles). (scapulae and clavicles). Again, we differentiate several subgroups within this conglomerate.

3.1 Superficial layer

This includes the trapezius and the splenius (capitus and cervicis). The most important of all is the trapezium, since it joins practically the entire neck to the back.. Its main functions are elevation and rotation of the scapula, stabilization of the scapula, production of depressive movements and acts as an extensor of the head and cervico-dorsal spine.

3.2 Deep layer

The deep musculature of the posterior neck includes the transverse-spinal or transverse-spinous muscles. Among other things, they are responsible for cervico-cranial stability.but we will not dwell too much on their particularities due to the anatomical complexity involved.

3.3 Deepest layer (deepest layer)

Also known as the suboccipital triangle, this layer is composed of the following three muscles: the posterior rectus abdominis muscle (superior and medial), the superior oblique muscle of the head (superior and lateral) and the inferior oblique muscle of the head (inferior and lateral).

The vertebral artery, the posterior arch of the atlas (the first cervical vertebra, C1) and the suboccipital nerve pass through this muscular conglomerate. Its clearest function is to provide fine motor function to the head and neck..

Summary

As you can see, the neck muscles are divided into seven total sections: three of the anterior triangle, one lateral (on each side of the neck) and three of the posterior triangle. Their functionalities are quite varied, as these range from swallowing to structural fixation to speech, breathing, movement production and much more.

The head is so posturally versatile thanks to these muscle groups that without them, something as simple as turning the head to avoid danger would be impossible.. As we agglomerate almost all our sensory centers in the cephalic region, it is essential that the cephalic region be able to adopt different postures and movements in order to receive as much information as possible to respond adequately to environmental pressures.

Bibliographical references:

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