ASK THE EXPERT: What Is Causing The Pain Under My Kneecap?

The knee is a complicated structure with tons of muscles and ligaments that can become injured and cause pain. Many of our patients come to us after experiencing persistent knee pain desperate to find the underlying cause of the discomfort. If you are experiencing pain in your knee, specifically under your kneecap, one common cause of this may be Patellofemoral Pain Syndrome (PFPS), a condition in which the area under your kneecap is irritated and causes pain.


The underside of the kneecap, or patella, is covered in cartilage that can become irritated if there is excessive rubbing between the kneecap and femur bone. The pain is typically aggravated by activities that cause compression around the patellofemoral joint including biking, weight-lifting, and (the most common) running. PFPS can affect anyone but we mostly see it in the younger, more active population.


1. Kneecap Movement Dysfunction: Normal movement of the kneecap should be up and down, but if a movement dysfunction is present it may move side-to-side. If this occurs, it can place a large amount of pressure behind the kneecap in areas that aren’t used to compression, resulting in irritation and pain.

2. Muscle Imbalance: Muscle imbalances {i.e. one muscle is markedly more dominant than another} can affect the movement of the knee, resulting in irritation behind the kneecap. Let’s say your hip stabilizing muscles aren’t working properly — your knee may move inward or outward depending on the dominant or weak muscle. This repetitive motion while participating in activities that already cause compression around the patellofemoral joint builds pressure behind the kneecap, causing pain.

3. Overuse: PFPS is most common in endurance athletes who participate in activities that place repetitive force on the knee joint. The repetitive nature of these activities can wear down the cartilage, irritating the kneecap and causing pain. It is also common to experience an overuse injury in conjunction with one of the two previous mentioned causes of PFPS.


Many patients feel markedly better after resting from strenuous activities for a few days, but if you find that isn’t helping, give physical therapy a try! Physical therapy can help reduce pain and prevent future pain by treating the underlying cause of the PFPS. This can be done by strengthening surrounding muscles and retraining proper body mechanics. Trigger point dry needling is also effective in restoring proper muscle firing through the knee joint.

Whatever the cause of your Patellofemoral Pain Syndrome, our certified physical therapists can identify and fix the underlying issue so you can get back to your active lifestyle.

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