If you have patellofemoral pain syndrome, you probably already know the feeling well: a dull, aching pressure behind or around the kneecap that flares when you go down stairs, sit for long periods, squat, or run.

If your knee pain sits just below the kneecap, worsens when you fully extend your leg, and has persisted despite rest, anti-inflammatories, and a round or two of physical therapy, you may already know the diagnosis: Hoffa's fat pad syndrome, also called infrapatellar fat pad impingement.

If you are dealing with a coronary ligament sprain, you are probably familiar with the frustrating pattern: pain along the knee joint line, sometimes present with every step, sometimes triggered only by squatting or rotating.

If you have lateral patellar compression syndrome, you have almost certainly been told to strengthen your VMO, stretch your IT band, and tape your kneecap. That advice is not wrong — but for a significant portion of people, it is incomplete.