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How does ankylosing spondylitis affect the spine and sacroiliac joints?
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arthritis
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Ankylosing spondylitis is a chronic inflammatory condition that primarily targets the sacroiliac joints and the vertebral column.1
The disease typically follows a progressive pattern:
- Initial Onset: Arthritis first manifests in the sacroiliac joints, which connect the base of the spine to the pelvis.1
- Progression: Inflammation gradually spreads upward through the spinal column.1
- Structural Changes: Extensive inflammation leads to the fusion (ankylosis) and deformity of the spine. This process often results in a characteristic "bamboo spine" appearance on radiographs, which signifies the loss of spinal mobility and the development of a rigid, deformed structure.12
Common symptoms associated with this spinal involvement include chronic lower back pain, which often improves with physical activity, and a general limitation in range of motion.12