Presentation
Pain and restricted movement of the knee joint. No history of trauma
Patient Data
MRI shows an intact anterior cruciate ligament (ACL), but it appears thickened and with increased signal intensity on PDFS and T2W, displaying a 'celery stalk' appearance, consistent with mucoid degeneration. Additionally, there is a small joint effusion and a ganglion cyst adjacent to the anterior aspect of the medial collateral ligament (MCL).
Case Discussion
The MRI findings are consistent with mucoid degeneration of the ACL.
These changes are easily detected on MRI, in contrast to arthroscopy, especially with the standard anterior portal approach, which typically shows a normal-appearing ACL.
Differential diagnosis should include acute or chronic interstitial partial tears of the ACL. However, in cases of mucoid degeneration, secondary signs of ACL injury are absent.
Treatment is usually not necessary.