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.

That persistent ache behind your kneecap — when you stand after sitting too long, when you take stairs, when you push through a workout and pay for it the next day — is one of the most common joint complaints in active and sedentary people alike.

If you have been told you have patellofemoral arthritis, you have probably received the standard advice: lose weight, strengthen your quadriceps, avoid stairs when flared, and take anti-inflammatories as needed.

The pain sits just outside the joint — around it, not inside it. Sometimes it is the soft tissue below the kneecap, sometimes it is the inner side of the knee where three tendons converge, sometimes it is a bursa quietly inflamed for months before anyone pays attention.

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.