ATLANTOAXIAL INSTABILITY

Questions and Answers

Atlantoaxial Instability Symptoms:

AAI symptoms can range from mild to severe, depending on the extent of instability and whether the spinal cord or brainstem is compressed. Also, some patients remain asymptomatic for long periods, while others may experience a variety of neurological and physical symptoms.

Neck Pain

• Persistent or intermittent pain in the upper neck is a common symptom of AAI. Unfortunately, the pain may worsen with movement or certain head positions.

Neurological Symptoms

• Headaches: Pain at the base of the skull that radiates towards the forehead, often due to pressure on the spinal cord or nerves.
• Numbness or Tingling: Paresthesia (numbness or tingling) in the arms, legs, or fingers can occur if nerve roots are compressed.
• Weakness: Muscle weakness, particularly in the arms or legs, may develop due to impaired nerve function.
• Balance Issues: Difficulty walking or maintaining balance due to compression of the spinal cord or brainstem.
• Loss of Coordination: In some cases, patients find a loss in motor skills motor skills, leading to difficulty with tasks like buttoning a shirt or writing.

Spinal Cord Compression

• Myelopathy: In severe cases, AAI may lead to myelopathy, which is damage to the spinal cord. In addition, these symptoms include increased reflexes, spasticity, and difficulty controlling bowel or bladder function.
• Dysphagia: Some individuals may experience difficulty swallowing if the instability affects the nearby nerves controlling this function.

Torticollis (Wry Neck)

• Some patients may develop torticollis, where the head is held at an abnormal angle due to muscle spasms in the neck, often as a compensatory mechanism for the instability.

How it is Diagnosed:

Diagnosing AAI involves a combination of clinical evaluation, imaging studies, and, in some cases, neurological testing.

Physical Examination

• A physician will assess neck movement, check for tenderness, and evaluate any neurological symptoms such as numbness, weakness, or balance issues.

Imaging Studies

• X-rays: X-rays of the cervical spine, particularly dynamic X-rays (taken while the neck is flexed and extended), are often used to detect abnormal movement between the atlas and axis.
• MRI: An MRI can provide detailed images of the spinal cord, ligaments, and soft tissues to identify if there is any compression of the spinal cord or nerves.
• CT Scan: A CT scan offers a more detailed view of the bone structures, and doctors can use the scans to identify fractures or congenital anomalies such as os odontoideum.
• Flexion-Extension X-rays: These are taken to observe how the neck bones move during flexion and extension and to evaluate for abnormal mobility at the atlantoaxial joint.

Neurological Evaluation

• If symptoms suggest spinal cord involvement, the orthopedist may assess reflexes, muscle strength, and coordination.

Atlantoaxial Instability Risk Factors:

Certain factors may increase the risk of developing atlantoaxial instability. Clearly, they include a history of trauma or injury to the cervical spine, congenital abnormalities, connective tissue disorders, and conditions that affect the integrity of the ligaments and joints in the neck.

Non-Surgical Treatment:

In cases where AAI does not cause severe neurological symptoms or spinal cord compression, doctors may implement non-surgical management. Non-surgical treatments are aimed at stabilizing the spine, managing pain, and improving quality of life.

Cervical Bracing

• Soft or Rigid Collars: Doctors may prescribe a cervical collar to immobilize the neck, especially following trauma. Doctors may prescribe a soft collar for short-term relief, while a rigid collar provides more stability.
• Halo Brace: In some cases, particularly if there is significant instability but surgery is not an option, a halo brace may be used. This device immobilizes the head and neck to prevent further movement and promote healing.

Physical Therapy

• Strengthening Exercises: A structured physical therapy program can help strengthen the neck and upper back muscles to provide better support to the spine.
• Posture Correction: Physical therapists work with patients to improve posture, which can reduce strain on the cervical spine and alleviate symptoms.
• Range of Motion Exercises: Controlled and gentle range of motion exercises can help maintain flexibility in the neck without exacerbating instability.

Pain Management

• Medications: Doctors may recommend over-the-counter pain relievers or nonsteroidal anti-inflammatory drugs (NSAIDs). For more severe pain, doctors may prescribe prescription medications such as muscle relaxants or nerve pain medications.
• Heat and Ice Therapy: Alternating between heat and ice packs can help reduce inflammation and alleviate muscle spasms around the neck.

Lifestyle Modifications

• Activity Restrictions: Patients may need to avoid high-impact activities that could worsen the instability or lead to further injury. Patients should not participate in contact sports, heavy lifting, or activities that involve sudden neck movements.
• Ergonomic Adjustments: Adjusting the work environment to improve ergonomics can reduce strain on the neck and improve long-term outcomes. This might include adjusting computer screens to eye level and using supportive chairs.

Atlantoaxial Instability Surgical Treatment:

Surgery becomes necessary for atlantoaxial instability (AAI) when conservative approaches like bracing or medication fail to control symptoms or prevent neurological deterioration. Accordingly, the specific surgical procedure used depends on the severity and cause of the instability. Meanwhile, here’s an overview of several common approaches:

Posterior Translaminar Fixation:

This minimally invasive option uses screws and rods placed through the lamina (flat part) of the C1 and C2 vertebrae to achieve fusion and stability. In conclusion, it’s suitable for mild AAI cases.

Transoral Anterior Odontoidectomy and Fusion:

This procedure involves removing part of the odontoid process (protrusion from C2) through the mouth and stabilizing the joint with bone grafts and plates/screws. Similarly, this procedure is suitable for AAI with odontoid malformations or compression.

Occipito-Cervical Fusion:

Fuses the skull (occiput) to the upper cervical spine (C1-C2 and sometimes additional vertebrae) with rods and screws. Meanwhile, this procedure offers maximum stability for severe AAI or ligamentous weakness.

Anterior C1-C2 Transarticular Screw Fixation:

Employs screws directly through the vertebral joints for improved stability.  Moreover, this procedure is often used for fractures or ligamentous laxity.

Gallie or Brooks Fusion:

This procedure uses wire and bone grafting to connect the posterior arch of C1 to the lamina of C2. In brief, this procedure is suitable for mild AAI requiring less invasive intervention.

Magerl Technique:

This procedure employs C1-C2 trans articular screws with posterior wiring for added stability. As a consequence, this procedure is used for various AAI scenarios.

Recovery:

• Typically involves wearing a halo-vest for several weeks to immobilize the spine while fusion occurs.
• Physical therapy plays a crucial role in regaining mobility and strength.
• Full recovery can take several months, depending on the complexity of the surgery.

Complications:

Complications of atlantoaxial instability may include persistent pain, neurological deficits such as weakness or paralysis. Also, loss of sensation or function in the arms or legs, and in rare cases, life-threatening complications such as spinal cord injury or respiratory compromise may occur.

Physical Therapy Recommendations:

Physical therapy plays a crucial role in the management of atlantoaxial instability. Therefore, it’s important to focus on improving neck strength and stability, enhancing range of motion, and reducing pain and inflammation. Regardless, therapeutic exercises, manual therapy techniques, and modalities such as heat or cold therapy may help with a comprehensive rehabilitation program.

Prevention Actions:

While some cases of atlantoaxial instability may be unavoidable due to congenital factors or underlying medical conditions, preventive measures such as avoiding high-risk activities that may lead to a cervical spine injury, maintaining good posture, and participating in regular exercises to strengthen neck muscles can help reduce the risk of complications.

Related Conditions:

Atlantoaxial instability may combine with other spinal conditions. Briefly, cervical spondylosis, spinal stenosis, and cervical radiculopathy can further contribute to symptoms and complications.

Living with the Condition:

Living with atlantoaxial instability may require ongoing medical management, including regular monitoring of symptoms, adherence to treatment recommendations, and modifications to daily activities to avoid neck pain or discomfort. Therefore, it’s essential to maintain open communication with healthcare providers and seek prompt medical attention for any new or worsening symptoms.

Long-Term Benefits of Atlantoaxial Instability Treatment:

With proper diagnosis and treatment, many individuals with atlantoaxial instability can experience significant improvement in symptoms and quality of life. Thus, surgical intervention, when indicated, can help stabilize the cervical spine, relieve pressure on the spinal cord or nerve roots, and prevent further neurological deterioration, leading to long-term benefits and improved functional outcomes.

Choosing the Southwest Scoliosis and Spine Institute:

When it comes to managing complex spinal conditions such as atlantoaxial instability, choosing the right healthcare team is crucial. The Southwest Scoliosis and Spine Institute, led by renowned spine surgeons Richard Hostin, MD, Devesh Ramnath, MD, and Ishaq Syed, MD, with offices in Dallas, Plano, and Frisco, Texas, offers comprehensive care and state-of-the-art treatment options for patients with spinal disorders. With their expertise, advanced surgical techniques, and commitment to patient-centered care, the team at the Southwest Scoliosis and Spine Institute provides compassionate, personalized treatment plans tailored to each individual’s unique needs, ensuring the best possible outcomes for patients living with atlantoaxial instability and other spinal conditions.

In conclusion, atlantoaxial instability is a complex spinal condition that can have implications for a person’s quality of life. With early diagnosis, treatment, and ongoing management, individuals with this condition can experience symptom relief and improved function, enabling them to lead fulfilling lives. Nevertheless, choosing a trusted healthcare provider such as the Southwest Scoliosis and Spine Institute can make all the difference in achieving optimal outcomes and ensuring the best possible care for those living with this challenging condition.

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Citation: Medscape – Atlantoaxial Instability

The medical content on this page has been carefully reviewed and approved for accuracy by the Southwest Scoliosis and Spine Institute’s qualified healthcare professionals, including our board-certified physicians and Physician Assistants. Our team ensures that all information reflects the latest evidence-based practices and meets rigorous standards of medical accuracy, with oversight from our expert spine doctors to guarantee reliability for our patients.