Fluoroscopy-Assisted C1–C2 Posterior Fixationfor Atlantoaxial Instability

Atlantoaxial instability, a condition involving the destabilization of the C1-C2 segment of the cervical spine, can result from factors like odontoid fractures, arthritis, and cervical tumors.

Surgical stabilization of the atlantoaxial joint is crucial to prevent these issues and improve patient outcomes. Early diagnosis and appropriate treatment are important to prevent worsening symptoms and neurological complications.

At Complete Orthopedics, our experienced spine surgeons provide advanced evaluation and treatment for complex cervical spine conditions, including surgical stabilization when needed. This page explains the causes, symptoms, diagnosis, treatment options, and recovery process for atlantoaxial instability.

How Common It Is and Who Gets It

Atlantoaxial instability is relatively rare but can occur due to trauma, degenerative disease, or congenital conditions. It is often diagnosed in patients with cervical spine fractures, severe arthritis, or spinal tumors. Treatment typically occurs when conservative methods fail to relieve symptoms, or if there is a significant risk of neurological deficits.

Why It Happens

The most common causes of atlantoaxial instability are:

• Odontoid Fractures: Damage to the odontoid process (the peg-like structure on the second cervical vertebra) that can destabilize the cervical spine.
• Arthritis: Degenerative arthritis, such as rheumatoid arthritis, can weaken the joints and ligaments, leading to instability.
• Cervical Tumors: Tumors in the cervical spine can cause structural damage and instability.
• Congenital Defects: Some individuals may be born with abnormalities that predispose them to atlantoaxial instability.

In these conditions, the abnormal movement of the C1 and C2 vertebrae can compress the spinal cord, leading to pain, weakness, and potential neurological impairment.

How the Body Part Normally Works

The cervical spine consists of seven vertebrae, with the first two vertebrae (C1 and C2) playing a critical role in head movement and stability. The C1 vertebra, also called the atlas, supports the skull, while the C2 vertebra (axis) allows rotation of the head. The atlantoaxial joint is formed by the articulation of the atlas and axis, with ligaments and bones maintaining the alignment and stability of the cervical spine. Any damage to these structures can disrupt spinal function and cause instability.

What You Might Feel

Symptoms of atlantoaxial instability can include:

• Neck Pain: Often associated with limited range of motion.
• Headaches: Often originating from the base of the skull.
• Weakness: In the arms or legs, often indicating spinal cord compression.
• Numbness: In the arms, hands, or other extremities.
• Bowel or Bladder Incontinence: In severe cases, due to spinal cord compression.
• Loss of Balance: Difficulty walking or maintaining balance, indicating neurological involvement.

How Doctors Find the Problem

Diagnosis is typically made through a combination of clinical examination and imaging studies:

• X-rays: Can show alignment issues and help identify instability.
• MRI: Provides detailed images of soft tissue, including the spinal cord and ligaments.
• CT scans: Useful for evaluating bone structures and detecting fractures or tumors.
• Fluoroscopy: During surgery, this real-time imaging can assist with screw placement and verify that the vertebrae are aligned.

Classification

Atlantoaxial instability is classified based on its underlying cause and the extent of instability:

• Odontoid Fractures: Fractures of the odontoid process that cause instability.
• Degenerative Arthritis: Arthritis affecting the C1-C2 joints, leading to instability.
• Traumatic Injuries: Dislocations or fractures resulting from trauma to the neck.
• Tumors or Infections: That disrupt normal alignment and stability.

Other Problems That Can Feel Similar

Conditions such as cervical spondylosis, cervical herniated discs, or myelopathy can produce similar symptoms, such as neck pain and neurological deficits. Accurate diagnosis is necessary to distinguish atlantoaxial instability from these other conditions.

Treatment Options

• Non-Surgical Care: For mild cases, physical therapy, pain management, and cervical collars may be used to manage symptoms.
• Surgical Care: If non-surgical treatments fail or if the condition worsens, surgical options include:
  • Atlantoaxial Transarticular Screw (TAS): A technique to stabilize the C1-C2 joint using screws placed through the atlantoaxial joint.
  • Screw and Rod Construct (SRC): A more comprehensive method involving screws and rods to stabilize the cervical spine.

Recovery and What to Expect After Treatment

Post-surgery recovery varies, but most patients can expect to stay in the hospital for a few days. After surgery, physical therapy is often needed to restore mobility and strength. The recovery process may take several weeks to months, with activity restrictions such as avoiding heavy lifting and strenuous movement. Full recovery is usually achieved within 3 to 6 months.

Possible Risks or Side Effects

As with any spinal surgery, atlantoaxial stabilization carries certain risks:

• Infection: Infection at the surgical site.
• Nerve Injury: Damage to nearby nerves during surgery, leading to neurological deficits.
• Vertebral Artery Injury (VAI): If the screws are misaligned, the vertebral artery may be damaged.
• Hardware Failure: The screws or rods may shift or break, requiring further intervention.
• Blood Loss: Significant blood loss can occur, especially with larger incisions or complex procedures.

Long-Term Outlook

The long-term outlook for atlantoaxial instability is generally good, especially with timely surgical intervention. The majority of patients experience significant relief from symptoms and can return to normal activities. However, complete recovery can take several months, and proper rehabilitation is essential for optimal outcomes.

C1-C2 Facet Joint Illustrated

Out-of-Pocket Cost

This procedure under CPT code 63020 at Complete Orthopedics is covered by Medicare and most major insurance carriers (Aetna, Anthem BCBS, Cigna, Empire BCBS, UnitedHealthcare), as well as most workers’ compensation and no-fault insurance plans. Your out-of-pocket cost depends on your specific plan, deductible, and the medical necessity criteria that apply to your case.

Call our billing team at (631) 981-2663 before scheduling to verify your coverage and discuss expected out-of-pocket costs. For the full list of carriers we accept and patient billing protections, see our Insurance Information page.

Summary and Takeaway

Atlantoaxial instability is a serious condition that can cause significant pain and neurological deficits. Surgical stabilization, using techniques like the atlantoaxial transarticular screw (TAS) and screw and rod construct (SRC), offers effective treatment. The recovery period can be lengthy, but most patients experience significant improvement in symptoms and return to daily activities within months. Early intervention is key to preventing permanent damage.