Parameniscal Cyst

Multilocular cystic mass communicates with a medial meniscus horizontal tear.
DD of parameniscal cysts:
1-Ganglion/Synovial cyst: does not originate from meniscal tear.
2-Bursitis.
3-Cystic masses e.g. hematoma, hemangioma or rarely cystic neoplasms.
4-Popliteus tendon sheath when filled with fluid (vs posterior horn lateral meniscal cyst)
If a cyst is present at the joint line or continuous with a mensical tear, then assume a meniscal origin of the cyst (as in the present case).
Treatment: resection of cyst and repair of tear.
Reference: Stoller, et al. Diagnostic Imaging: Orthopedics. Amirsys
Credit: Dr Ahmed Haroun
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