Knee anatomy - the medial plica

A medial plica is a remnant of an embryonic partition in the knee, and runs along the inner aspect of the kneecap.

It may also be called a 'medial shelf' - more a vertical shelf than a horizontal one, mind - and runs down from above the patella to the fat pad below the patella.

ANATOMY OVERVIEW anatomy intro bones from front (bent knee) bones from front (straight knee) bones from side bones from above patella capsule collateral ligaments cruciate ligaments medial plica meniscus from side meniscus from top muscles from front muscles from back

As the knee bends the 'shelf' of tissue may also give a sudden snap over the rounded ends of the femur bone.

When a medial plica becomes abnormally thickened, it can be felt with the finger as a string-like object to the inner aspect of the kneecap.