Can axial spondyloarthritis (axial SpA) involve the cervical spine?

Cervical Involvement in Axial Spondyloarthritis

Yes, axial spondyloarthropathy commonly involves the cervical spine, with the cervical spine being the most frequently affected region in patients with advanced disease and spinal ankylosis. 1

Prevalence and Characteristics of Cervical Involvement

• The cervical spine is the most frequently involved region for fractures in patients with axial spondyloarthritis (axSpA) who develop spinal ankylosis 1
• Recent evidence shows that structural changes in the cervical spine may occur during early periods of axSpA, even in non-radiographic stages 2
• A 2024 study found that cervical spine involvement was present in 53.2% of axSpA patients 3
• Cervical spine involvement is associated with:
  • Higher disease activity
  • Worse functionality and mobility
  • More extensive structural damage throughout the spine 3

Patterns of Cervical Involvement

• In both ankylosing spondylitis (radiographic axSpA) and non-radiographic axSpA, the cervical modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) values are higher than lumbar mSASSS values in the majority of patients (82.8% and 89.5%, respectively) 2
• Zygapophyseal joint (ZJ) involvement in the cervical spine:
  • Present in 29.1% of axSpA patients
  • Can occur independently of vertebral body involvement in some patients
  • Associated with worse mobility and more radiographic damage 3

Diagnostic Imaging for Cervical Involvement

• Initial imaging for suspected axSpA should include radiographs of the sacroiliac joints 1
• For cervical spine assessment:
  • Conventional radiography of the cervical spine is recommended to detect syndesmophytes, which are predictive of the development of new syndesmophytes 1
  • MRI of the cervical spine can detect inflammatory changes before radiographic damage is evident 4
  • CT is particularly valuable when fractures are suspected in patients with spinal ankylosis 1

Clinical Implications and Management

• Cervical spine involvement increases the risk of fractures in patients with ankylosis 1
• These fractures are often unstable, involving all three spinal columns, and associated with high rates of neurologic deficits (21-100% of cases) 1
• Delayed diagnosis of cervical fractures occurs in 15-41% of cases, highlighting the need for high clinical suspicion and early advanced imaging 1
• Surgical fixation is often required for cervical fractures in axSpA, though outcomes may have high morbidity and mortality 1

Monitoring Recommendations

• Regular assessment of disease activity using validated tools like ASDAS-CRP (Ankylosing Spondylitis Disease Activity Score) is necessary for monitoring disease progression 4
• MRI of the spine may be used to assess and monitor disease activity, providing additional information beyond clinical and biochemical assessments 1
• Conventional radiography of the spine should not be repeated more frequently than every two years for monitoring structural changes 1

Clinical Pitfalls to Avoid

• Over-reliance on inflammatory markers can lead to missed diagnoses, as normal ESR/CRP levels do not rule out axSpA (sensitivity only 50%) 4
• Delayed diagnosis (average 7-10 years from symptom onset) can occur due to:
  • Over-reliance on radiographs
  • Ignoring inflammatory back pain patterns
  • Neglecting extra-articular manifestations 4
• When cervical spine fracture is suspected in axSpA patients with ankylosis, negative radiographs should be followed by cross-sectional imaging (CT or MRI) due to the high risk of missed fractures 1

Understanding the high prevalence of cervical involvement in axSpA is crucial for appropriate management and prevention of complications, particularly in patients with advanced disease who are at risk for cervical fractures with potentially severe neurological consequences.