Presentation
Known case of ankylosing spondylitis with history of falling. Attends the emergency department.
Patient Data
![](https://prod-images-static.radiopaedia.org/images/29750539/f653435a902bd543f5f7161db1edaa_thumb.jpeg)
![](https://prod-images-static.radiopaedia.org/images/29750547/e1c5880d981d4d6b1b626bf56cebad_thumb.jpeg)
![](https://prod-images-static.radiopaedia.org/images/29750539/f653435a902bd543f5f7161db1edaa_big_gallery.jpeg)
In lumbar and pelvic frontal views, ankylosis of bilateral sacroiliac joints is seen.
Interspinous ligament calcification is seen as 'dagger' spine associated with 'bamboo spine' is depicted.
All findings are secondary to ankylosing spondylitis.
![](https://prod-images-static.radiopaedia.org/images/29750555/866bfe49a78ccd5db296658ec2c4f1_thumb.jpeg)
![](https://prod-images-static.radiopaedia.org/images/29750564/3329356854feae5916fb3420cad975_thumb.jpeg)
![](https://prod-images-static.radiopaedia.org/images/29750555/866bfe49a78ccd5db296658ec2c4f1_big_gallery.jpeg)
Syndesmophytes, ankylosis of bilateral costovertebral and post facet joints associated with fracture line (arrow) with extension from anterior vertebral body to posterior part of vertebral body characteristic of chalk stick fracture is depicted.
![](https://prod-images-static.radiopaedia.org/images/29725515/bf01c1ff72158681b88cca3f50f057_thumb.jpeg)
![](https://prod-images-static.radiopaedia.org/images/29725537/1744cc1e05b2fcffa377f9d91bc7a5_thumb.jpeg)
![](https://prod-images-static.radiopaedia.org/images/29725538/0aa11515b8370d215ad43a9ba04eae_thumb.jpeg)
![](https://prod-images-static.radiopaedia.org/images/29725515/bf01c1ff72158681b88cca3f50f057_big_gallery.jpeg)
Beside typical findings of ankylosing spondylitis e.g. calcification of interspinous ligaments, shiny corner sign, syndesmophytic ankylosis and Anderson lesion, patient suffer from chalk stick fracture (arrow) after falling, a type of fracture that occurs in fused spine.
Case Discussion
Chalk stick fracture of fused spine seen in patient with history of ankylosing spondylitis.