Cervical spine instability - information, diagnosis and treatment
The instability of a motion segment of the cervical spine usually develops first in the biomechanical heavily loaded segment between the fifth and sixth cervical vertebrae. The most common cause for instability of the cervical spine is the natural aging process. Symptomatic is the instability of the cervical spine by severe neck pain. Later there may be misaligned, which may lead to a narrowing of the nerve or even the spinal cord. This type of condition necessitates a stabilization surgery of the cervical spine.
How is the "instability" defined?
"Instability" means that due to repeated stress and strain the spine cannot maintain its original mobility without causing a breaking down (degenerating) of the nerves, an extensive deformation or severe pain. (Panjabi and White).
What causes instability of the cervical spine?
Most often, the instability of the cervical spine is caused by the everyday wear and tear on the spine. In most cases, the biomechanical heavily loaded intervertebral disc between the fifth and sixth cervical vertebrae is affected first. Dehydration and loss of disc height, lack of joint conclusion of the small vertebral joints with loosening of the joint capsules and the stabilizing ligaments are the mechanisms from which the instability occurs. The person complains of neck pain. If, additionally it has come to a deformity, the nerve roots or even the spinal cord are affected. The result is weakness or loss of coordination, unsteady gait and pain, numbness and even paralysis in the arms.
How is instability of the cervical spine diagnosed?
First, the spine specialist performs a thorough physical and neuro-orthopedic examination to gain an overview of the extent of pre-existing symptoms. The next step is an MRI of the cervical spine performed to assess the width of the spinal canal, the condition of the intervertebral discs and facet joints, and particularly damage to the spinal cord and nerve roots. In a last step, radiographs, so-called "functional images", of the cervical spine from the front and from the side are obtained. The latter refer to the images of the cervical spine from the side showing in a forward and reverse tilt position of the head. This allows for determining whether an unnaturally enhanced mobility is present in the affected segment.
What are the treatment options for cervical spine instability?
Basically, the instability of the cervical spine is treated conservatively, commonly with physiotherapy and physical therapy. The pain can be treated by medication. Analgesic and anti-inflammatory medications are also injected specifically to the facet joints of the cervical spine. For radiating pain in the arm, a local anesthetic and a cortisone preparation is injected under CT guidance directly to the nerve root to relieve the pain and to stop the inflammation of the nerve root.
A cervical fusion surgery (stiffening) is recommended only if a) according to the regularly carried out X-ray examinations the instability increases and threatens a deformity of the cervical spine, b) if the complaints do not subside or cannot be controlled despite intensive conservative therapy or c) permanent damages to the spinal cord and nerve roots are present or are to be expected.
What are the procedures of a cervical spine fusion surgery?
The fusion surgery as most other cervical spine surgeries is performed from the front (anterior approach) to prevent manipulation of the spinal cord. The access to the cervical spine is performed by a small transverse cut of about 3-4 centimeters in length. The respective cervical disc is removed under the microscope.
The adjacent vertebrae are now supported by inserting a placeholder made of plastic in the former intervertebral disc space. In a case of a marked instability, a short plate should be inserted additionally.
The hospital stay after a fusion surgery of the cervical spine is about three days. After surgery, the cervical spine should be immobilized for two weeks by wearing a soft cervical collar. After the two weeks, the cervical spine can be moved again. Sports like swimming and light jogging can be resumed. All other sports should be suspended for at least three months.