Discomfort is typically felt on the inner aspect of the knee. A medial plica may be palpable as a tender cord-like structure on the lower inner quadrant of the knee.
This medial plica is being nipped between patella and femur during joint movement. Above the knee the suprapatellar plica may become nipped between the femur and the quadriceps tendon.
Such trauma can cause the tissue fold to become inflamed and thickened, and then nippling (catching) can occur more often.
Treatment of Plica syndrome
Different plicae can cause different symptoms - the common problematic plica is located on the medial (inner) aspect of the knee and it can become traumatised between the bones.
Treatment may includes anti-inflammatory medication, local steroid injection, physiotherapy to strengthen the quadriceps and hamstrings muscles and arthroscopic surgery to remove the structure entirely.
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.
Medial plica irritation: diagnosis and treatment. Griffith CJ and LaPrade RF. Curr Rev Musculoskelet Med. 2008 Mar; 1(1): 53–60.
Anatomy and MR Imaging Appearances of Synovial Plicae of the Knee. García-Valtuille R, Abascal F, Cerezal L, García-Valtuille A, Pereda T, Canga A, Cruz A. RadioGraphicsVol. 22, No. 4.