There may also be a snapping sensation as the knee is bent. This is due to the rubbing of the thickened plica over the round edge of the medial femoral condyle . There is usually tenderness over the area where the plica is located. In thin people, the tissue that forms the plica may be actually be felt as a tender band underneath the skin. If the irritation from the plica is particularly bad, there may be swelling in the entire knee.
Diagnosis begins with a history and physical .
The examination will try to determine where the pain is located and whether or not the band of tissue can be felt. X-rays will not show a plica. X-rays are mainly useful to determine if other conditions are present if there is not a clear cut diagnosis. If there is a uncertainty in the diagnosis following the history and physical examination, or if other injuries in addition to the plica syndrome are suspected, a MRI scan may be suggested. Usually, this test is done to look for injuries, such as tears in the menisci or ligaments of the knee.