Causes

Plica problems can be either acute (sudden onset) or chronic (ongoing). Injuries that involve falling or hitting your knee can cause the medial plica to swell and become painful. Scarring and thickening of the plica can develop resulting in continuation of your symptoms.

Chronic plica problems develop when the medial plica is irritated by certain exercises that involve repeatedly bending and straightening the knee, such as biking or using a stair stepper machine.