Ankylosing spondylitis - Andersson lesion

Case contributed by Dr Ammar Haouimi


Chronic low back pain.

Patient Data

Age: 40 years
Gender: Male

The MRI sequences demonstrate an abnormal signal intensity of hemi-spherical shape involving the central portion of both vertebral halves and discs of T11-T12, T12-L1, and L3-L4 to L4-L5. They appear of low signal on T1, high signal on T2/STIR with enhancement on postcontrast sequences.

High signal on T2/STIR with enhancement of the interspinous ligaments in keeping with enthesitis.

The coronal STIR and postcontrast T1 fat sat show bilateral sacroiliitis.

Case Discussion

MRI features are consistent with Andersson lesions in a patient with ankylosing spondylitis

Andersson lesions are considered as an inflammatory spondylodiscitis that occurs in association with ankylosing spondylitis and results in a disc pseudarthrosis.


Additional contributor: A. Ramdani, MD


How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.