Spinal instability is a pathological mobility in its segment. In this case, either the amplitude of the normal movements increases, or new freedoms in the movements uncharacteristic of the normal state arise. An indicator of mobility is the displacement of the vertebrae. In this case, the displacement refers to the radiological finding and may not be accompanied by pain. Instability refers to the clinical concept and is characterized by pain.
The most vulnerable is the cervical area. She is responsible for the mental abilities of a person, his ability to speak, work with his hands and other “human” qualities. The cervical spine includes seven vertebrae. The first (“atlas”) does not have a body. Both the intervertebral disc and the spinous process are absent. "Atlas" is tightly spliced with a skull and carries all its load on itself. From the second cervical vertebra, a tooth (process) leaves. An “Atlas” is planted on it. Such a joint and joints between the vertebrae allow the first vertebra to rotate.
Due to the lack of disk, this area is not affected by osteochondrosis. However, quite often there is instability of the cervical vertebrae. Moreover, their position is characterized by increased mobility. The reason for the instability of the cervical spine in this area may be a congenital anomaly, injuries (including lungs). Increased mobility also occurs during prolonged use with the head tilted down and forward.
The rest, which are part of the cervical vertebrae, have a similar structure with the thoracic and lumbar vertebrae. This causes the occurrence of similar violations in them. These include: deterioration in the intervertebral discs and joints, the formation of osteophytes (bone growths). There are also hernias of the disc, which are able to compress the roots of the nerves. All this causes instability of the cervical spine.
This is the most mobile zone of the pillar. Especially around the fifth to seventh vertebra. It is this area that wears out faster than the rest. Due to the occurrence of painful processes, these vertebrae begin to cope poorly with their functions. Since they are not able to withstand the load, it is distributed to adjacent segments. Additional load causes instability of the cervical spine already in its next section.
The segments joined together form the spinal canal, the beginning of which is located in the region of the large foramen magnum. The transverse processes of the vertebrae of the cervical zone have an opening for arteries on each side. In aggregate, an arterial canal is formed. Instability of the cervical spine can lead to a lack of blood flow and, as a result, dizziness, impaired coordination, headaches, tinnitus, visual disturbances and more.
Increased mobility of segments can also contribute to the development of various autonomic disorders. This is due to the presence of a large accumulation of nodes of the nervous autonomic system among the soft tissues surrounding the cervical zone of the spine.
The functions of fixing and driving the upper segments of the column are performed by the muscles of its cervical region. Most of them have a rather thin structure and are very innervated. Any serious effect (hypothermia, sudden movement, uncomfortable posture, prolonged or increased load) can provoke a muscle spasm characterized by pain. At the same time, mobility in the neck often occurs. Even slight instability can provoke irritation in the nerve endings, a response spasm in the vessels and muscles. This manifests pain in the head, interscapular region and neck, dizziness and so on.