The cervical spine is designed to provide both mobility and stability. Strong bones, intervertebral discs, facet joints, ligaments, and muscles work together to maintain normal alignment while allowing the neck to move safely.
Cervical spinal instability occurs when one or more spinal segments move excessively or abnormally. This abnormal motion may lead to neck pain, nerve compression, spinal cord compression, progressive deformity, or neurological dysfunction.
Some forms of instability develop gradually from arthritis and aging, while others occur suddenly after trauma, infection, tumors, inflammatory conditions, or previous surgery.
Common cervical instability disorders include:
- Degenerative cervical instability
- Cervical spondylolisthesis
- Cervical retrolisthesis
- Dynamic cervical instability
- Atlantoaxial instability (C1-C2)
- Occipitocervical instability
- Postoperative cervical instability
- Traumatic cervical instability
Major Diagnosis Types
Below are the major types we see in our clinic. Click on available links to learn about our approach to the problems.
Adjacent Segment Disease
Adjacent segment disease can occur after a spinal fusion. The vertebrae included in a successful fusion no longer move independently, which can place additional mechanical stress on the spinal segments immediately above or below the fusion.
Changes seen on imaging alone are often called adjacent segment degeneration. The term adjacent segment disease is generally used when those changes begin producing symptoms, and my require treatment.
Pseudarthrosis
A pseudarthrosis is a spinal fusion that has failed to completely heal. It is sometimes called a nonunion.
After spinal fusion surgery, bone is placed between vertebrae with the goal of forming one solid piece of bone. Screws and rods maintain stability while the fusion heals.
If adequate bone growth does not occur, continued movement can remain at the surgical level. This problem can cause symptoms that may require additional treatment.
Minor Diagnosis Types
These terms are often encountered, but are either less often treated or described within one of the above diagnoses.
Atlantoaxial Instability (C1-C2)
Atlantoaxial instability affects the joint between the first and second cervical vertebrae.
This region normally provides a large portion of the neck’s rotational movement while maintaining stability around the spinal cord.
Causes include:
- Trauma
- Rheumatoid arthritis
- Congenital abnormalities
- Down syndrome
- Ligament injuries
- Previous surgery
Significant atlantoaxial instability may place the spinal cord at risk and often requires specialized evaluation.
Cervical Retrolisthesis
Retrolisthesis occurs when one vertebra shifts backward relative to the vertebra below.
Like forward slippage, retrolisthesis usually develops because of degenerative changes affecting the discs and facet joints.
Depending on its severity, retrolisthesis may contribute to:
- Foraminal stenosis
- Spinal canal narrowing
- Mechanical neck pain
- Nerve compression
Treatment depends on symptoms rather than imaging findings alone.
Cervical Spondylolisthesis
Cervical spondylolisthesis occurs when one vertebra slips forward relative to the vertebra below.
Most cervical spondylolisthesis develops from degeneration of the discs and facet joints.
Symptoms may include:
- Mechanical neck pain
- Arm pain
- Numbness
- Weakness
- Cervical myelopathy when spinal cord compression develops
Not every cervical spondylolisthesis requires surgery. Many remain stable for years.
Degenerative Cervical Instability
Degenerative cervical instability develops gradually as the normal stabilizing structures of the spine wear with age.
Contributing changes may include:
- Degenerative disc disease
- Facet arthritis
- Ligament degeneration
- Loss of disc height
- Weakening of supporting tissues
As degeneration progresses, one vertebra may begin moving excessively relative to the next.
This abnormal motion may produce mechanical neck pain, contribute to nerve compression, or accelerate additional degeneration.
Dynamic Cervical Instability
Dynamic instability refers to abnormal movement that occurs only during neck motion.
Standard MRI or CT scans obtained with the neck in a neutral position may not fully demonstrate dynamic instability.
Some patients experience symptoms primarily during movement, while static imaging appears relatively normal.
Dynamic instability is often evaluated using flexion and extension radiographs together with the patient’s symptoms and neurological examination.
Occipitocervical Instability
Occipitocervical instability involves abnormal motion between the skull and the upper cervical spine.
Although uncommon, this condition can be serious because important neurological structures pass through this region.
Potential causes include:
- Severe trauma
- Congenital abnormalities
- Connective tissue disorders
- Inflammatory disease
- Tumors
- Previous surgery
Patients may experience severe neck pain, headaches, neurological symptoms, or signs of spinal cord compression.
Traumatic Cervical Instability
Traumatic instability occurs when injury disrupts the normal stabilizing structures of the cervical spine.
Possible injuries include:
- Ligament tears
- Facet dislocations
- Fractures
- Disc disruption
- Combined injuries
Traumatic instability ranges from relatively minor injuries that heal without surgery to severe injuries requiring urgent stabilization.
Prompt evaluation is essential after significant neck trauma.