Plicae often mimic other conditions
Plicae are normal anatomical structures, so they are often ignored when the surgeon is investigating the problematic knee. They may cause clicking and catching and be mistaken for a meniscus problem, for example. But usually a careful arthroscopic examination will reveal thickening at areas that are being impinged or a bit of redness and some damage to underlying joint cartilage.
Synovial Plica Syndrome of the Knee: A Commonly Overlooked Cause of Anterior Knee Pain. Lee PYF, Nixion A, Chandratreya A and Murray JM. Surg J (N Y). 2017 Jan; 3(1): e9–e16.
'The Sneaky Plica' revisited: morphology, pathophysiology and treatment of synovial plicae of the knee. Schindler OS. Knee Surg Sports Traumatol Arthrosc. 2014 Feb;22(2):247-62. doi: 10.1007/s00167-013-2368-4. Epub 2013 Feb 5.
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