Discoid lateral meniscus

Case contributed by Heather Pascoe
Diagnosis almost certain


Recurrence right knee pain. ?Meniscal tear.

Patient Data

Age: 30 years
Gender: Male

Widening of the lateral joint space suggestive of a discoid lateral meniscus. No fracture of the distal femur or proximal tibia or fibula. Knee alignment is normal. No joint effusion.


The lateral meniscus is discoid, with no abnormal signal identified to suggest the presence of a tear within. The medial meniscus is unremarkable, with no tear or parameniscal cyst seen. The meniscal root attachments remain intact. No osteochondral injury identified. The posterolateral corner structures remain unremarkable. A suprapatellar joint effusion is present, with mildly thickened superior plica. No Baker's cyst identified. 

Case Discussion

The discoid meniscus is at higher risk of tearing compared to a normal meniscus however in this case no tear was identified.

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.