Presentation
Known case of ankylosing spondylitis
Patient Data
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Typical appearance of bamboo spine with multiple syndesmophytes between the vertebral bodies. Degenerative changes as endplate sclerosis and mild irregularity are seen. Normal lordosis of the lumbar spine is reversed.
There is a single central radiodense line related to ossification of supraspinous and interspinous ligaments which is called dagger sign.
Case Discussion
Typical bamboo spine and dagger sign in a known patient with ankylosing spondylitis. The dagger sign is a single central radiodense line on frontal radiographs related to ossification of supraspinous and interspinous ligaments which is seen in ankylosing spondylitis.