Posttraumatic cyclops lesion of the knee

Case contributed by Dr Roberto Schubert


History of knee trauma 5 months ago. Persistent pain on extension and "giving way" of the knee.

Patient Data

Age: 50
Gender: Male

There is a rounded mass with relatively low signal on both T1 and T2 weighted images between Hoffas fat pad and the tibial insertion of the anterior cruciate ligament. The ACL shows some signal alterations, as well. Its distal portion and part of the mass enhance after contrast.

Case Discussion

The findings are in keeping with posttraumatic arthrofibrosis following an injury of the ACL. This so-called cyclops lesion consists of scar tissue and may occur as a complication after LCA repair. Rarely, it can be encountered after partial ACL tears1.

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Case information

rID: 24892
Published: 18th Sep 2013
Last edited: 16th Jul 2018
Inclusion in quiz mode: Included

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