Cervicogenic vertigo refers to vertigo or dizziness caused by neck factors.
I. Etiology and pathology
The essence of vertigo is that the human body has disorders of spatial orientation or balance sensation. When the incoming signals from the vestibular, proprioceptive and visual triad of balance sensory system are not consistent, the central nervous system cannot balance and coordinate, which makes vertigo arise. Clinical data show that cervical spondylosis and vertigo are closely related, and vertigo accounts for more than half of the patients with cervical spondylosis; 60% of the patients over 50 years old who visit the clinic for vertigo have cervical spondylosis as a cause.
The theoretical mechanisms of vertigo caused by cervical spondylosis can be summarized into three types.
(i) Vertebral-basilar artery insufficiency of blood supply theory (VBI)
First: compression or distortion of the vertebral artery reduces the effective blood flow of the vertebrobasilar artery, resulting in dysfunction of the cochlear and vestibular nuclei innervated by its terminal branch, the posterior inferior cerebellar artery, and vertigo symptoms.
Secondly, the effect of head movement on the blood flow of vertebral artery: many scholars have proved that when the head is extended and rotated to the opposite side, the blood flow of vertebral artery is obviously reduced. When the vertebral artery is abnormally changed, such as the lumen diameter of vertebral artery is narrowed and the diameter of both vertebral arteries is extremely asymmetrical, the blood vessel is strained, twisted and twisted, etc., the reduction of blood flow of one side of vertebral artery will lead to the acute insufficiency of blood supply of the whole vertebral basilar artery and the occurrence of Vertebral artery blood flow disorder.
Third: the effect of degenerative changes in the cervical spine on vertebral artery blood flow: the reduction in the thickness of the cervical intervertebral disc makes the height of the cervical spine lower, causing the vertebral artery to become more distorted and bent to reduce vertebral artery blood flow. At the same time, vertebral osteophytes, which mainly occur in the lower cervical spine, can also lead to compression or displacement of the vertebral artery.
Fourth: the effect of blood rheology changes on the vertebral artery blood flow: the vertebral artery blood supply range has brainstem cerebellar vestibular system inner ear mesencephalon brain frontal lobe occipital lobe, etc., the vertebral artery branches cerebellar posterior and superior posterior artery insufficient blood supply, can cause contact cerebellar vestibular organs of the cerebellar vermis lobule ischemia and affect the balance. The former cerebellar hemispheres and the conduction associated with the anterior and posterior cerebellar tracts of the spinal cord and the spinal cord are affected, resulting in impaired postural maintenance. The rest of the cerebellar hemispheres are affected by conduction to the pontocerebellar tract and the brain, resulting in impaired postural coordination. Ischemia of the vestibular organs may lead to vertigo, balance disorders, postural disorders, staggering and unstable walking.
Segmentation of the vertebral artery
Segment I: The subclavian artery separates the vertebral artery upward between the anterior oblique and long cervical muscles to the C6 transverse foramen. This segment of the vertebral artery is anterior to the common carotid artery, the jugular vein, and posteriorly near the C7 transverse process, the inferior cervical sympathetic ganglion and the anterior branches of the C7 and 8 spinal nerves. In this segment, the anterior oblique muscle lesion can affect the vertebral artery and produce vertigo symptoms.
The second segment: it travels in the C6-2 transverse foramen. In the elderly, the vertebral artery in this segment is tortuous and the lumen may be narrowed due to compression of the vertebral artery by vertebral osteophytes, which may affect the blood supply and cause dizziness.
The third segment: after the C2 transverse foramen is penetrated to the front of the vertebral canal. This section of the vertebral artery first passes outward and backward through the C1 transverse foramen to the posterior aspect of the superior articular surface of the C1 lateral block and turns inward in a horizontal direction above the posterior atlantoaxial arch, passing through the vertebral artery sulcus and then through the posterior atlanto-occipital membrane into the spinal canal. This segment can stimulate and compress the vertebral artery due to the subluxation or hyperplasia of the atlantoaxial joint due to the travel of the vertebral artery.
The fourth segment: the vertebral artery enters the vertebral canal after passing through the posterior atlanto-occipital membrane and dura mater.
(B) Sympathetic nerve theory
Stimulation of the peripheral sympathetic nerve network can lead to intracranial and extracranial smooth muscle spasm of small blood vessels, insufficient blood supply to the internal carotid artery and basilar artery and clinical symptoms of sympathetic excitation or inhibition.
(C) Proprioceptive reflex vertigo
The maintenance and regulation of human posture mainly depends on the vestibular-spinal reflex, and the receptors involved in the vestibular-spinal reflex include the first proprioceptive receptors, including the muscle shuttle receptors, Golgi’s receptors, joint receptors, etc., which provide information on the spatial position and movement status of the trunk. The cervical extensors and intervertebral muscles have the highest density.
Clinical manifestations
1.Vertigo
It is mainly manifested as chronic recurrent episodes of vertigo or chronic persistent vertigo.
The characteristics of vertigo caused by vertebral artery ischemia are
First: episodes of intense vertigo.
Second: the onset of vertigo is often associated with a change in head position especially when the head is tilted back and rotated.
Third: the presence of dysfunction of the thalamic tract of the spinal cord and sudden fall and lunge.
Fourth: the patient is conscious at the onset.
The characteristics of sympathetic vertigo are.
First: the degree of vertigo is mild and of a somnolent nature.
Second: chronic and persistent presence.
Third: the onset and change of dizziness is not related to neck movement.
Fourth: it is lighter in the morning or after sleep or heavier in the afternoon or after exertion.
Fifth: coexistence with chronic headache.
Sixth: often with vision loss phenomenon cervical spondylosis.
The characteristics of cervical proprioceptive disorder vertigo are
First: vertigo is mild and of a somnolent nature.
Second: chronic and persistent presence.
Third: dizziness, aggravated by the forward flexion movement of the neck.
Fourth: it is reduced by morning or after sleep, and after heavier activities.
2: pain in the neck and collar area.
3: tinnitus and deafness.
4: Mental depression, lethargy and drowsiness.
5. eye symptoms.
III. Diagnostic criteria.
(1) Symptoms of episodic vertebrobasilar artery insufficiency associated with head and neck activity: such as headache, dizziness, visual disturbance, tinnitus, and positive neck turn test.
(2) Neck symptoms: neck muscle spasm, stiffness and pain, limitation of movement, pressure pain, sometimes upper extremity numbness and pain, positive sign of pull test.
(3) With symptoms of autonomic dysfunction: nausea, vomiting, sweating, chest tightness, palpitations.
(4) In severe cases, sudden onset of collapse may occur, usually when the head is tilted back, lateral flexion or rotation. There is usually no loss of consciousness at the time of collapse, which is relieved by the change of position and with the reset of the neck position.
(5) Concomitant symptoms: A series of symptoms and signs of brainstem ischemia may be present at the same time.
(6) X-ray manifestations: asymmetry on both sides of the atlanto-axial and atlanto-dental joints, skewed vertebral spine, vertebral hyperplasia, narrowing of the vertebral space, deformation of the hook vertebral joint, ligament calcification, and bone bridge formation are common.