Do your knees hurt when you squat? You might chalk it up to a case of knee arthritis. That’s one possibility. But there’s another well-described cause of knee pain worsened by squatting. In fact, it’s one of the most common causes of knee pain in people under the age of 60. It’s called patellofemoral syndrome and it makes squats, walking upstairs, or walking up an incline uncomfortable. Patellofemoral syndrome is also sometimes referred to as runner’s knee since it’s more common in runners and cyclists.
How common is this knee problem? At any one time, 6% of the population has a diagnosis of patellofemoral syndrome and it’s more prevalent in women than men. Patellofemoral syndrome can make workouts unpleasant because the pain is worsened when you flex your knees when doing certain exercises, particularly squats. Let’s take a closer look at why patellofemoral syndrome is so common and why women are at higher risk.
The Patellofemoral Joint and Why It Becomes Painful
Patellofemoral syndrome affects the patellofemoral joint. This joint is made up of the patella, or knee cap, and the trochlea of the femur. Various tendons and ligaments help to stabilize this joint as does the quadriceps muscle. That’s why strong quads are so important! The primary function of the patellofemoral joint is to extend the knee. It also helps your lower body and to decelerate when you’re walking downhill.
What Are the Symptoms of Patellofemoral Syndrome?
The classic symptom of patellofemoral syndrome is pain around the front of the knee and tenderness just underneath the knee cap of one or both knees. The pain may worsen when you flex your knee while weight bearing, when climbing stairs, or when you sit for a long period of time. You typically don’t experience knee swelling with this condition. If you do have swelling or redness around the knee, your knee pain likely has another cause that needs to be checked out as soon as possible, especially if you had a recent injury.
What Causes It?
Patellofemoral pain may come on after a series of intense workouts that excessively stress the knees. As mentioned, runners and cyclists are at risk, and if you run or cycle long distance without enough recovery time, it can lead to knee pain. In terms of weight training, an intense squat routine can bring on patellofemoral pain too. As with most overuse injuries, suddenly increasing the frequency of your workouts or their intensity can trigger the symptoms. However, some people are more susceptible to this condition than others. Why might this be? Initially, researchers believed a large Q angle played a strong role. The Q angle is the angle formed by the anterior superior iliac spine in your pelvis and the center of the kneecap. Women tend to have a large Q angle because they have a wider pelvis. A larger Q angle places more stress on the kneecap. But, research now suggests that this may not be a major factor after all.
Instead, people with patella femoral syndrome often have abnormal tracking of the knee cap. With abnormal tracking, when you bend or straighten your knee, the kneecap shifts slightly out of place, usually to the outside. The abnormal tracking worsens with exercises like squats. Some people with abnormal tracking also have dynamic valgus, a condition where the knee moves inward relative to the foot. This places extra force on the lateral part of the knee and contributes to abnormal tracking of the kneecap. Women athletes are more likely to have dynamic valgus and this may explain why they have more patellofemoral syndrome. Certain foot abnormalities can contribute as well. Look at your exercise shoes. If you see the medial part of your shoe is excessively worn, you may have pes pronatus, a common foot problem that increases the risk of patellofemoral syndrome.
Some people with pain in the areas where patellofemoral syndrome strikes also have chondromalacia patella, a condition where the articular cartilage underneath the kneecap breaks down. Over time, inflammation can set in. However, patellofemoral syndrome and chondromalacia patella are two distinct conditions.
How Do You Know if You Have Patellofemoral Syndrome?
If your pain is mild, a health care professional may make the diagnosis based on symptoms. If your symptoms don’t improve, they may recommend an imaging study to look for other causes of knee pain such as knee arthritis.
How do you treat patellofemoral syndrome? If it’s severe, you might benefit from physical therapy to strengthen your quads and core. Strengthening the quads is important because they stabilize the kneecap and help to keep the kneecap from tracking abnormally. Core strengthening helps too. A 2016 study of patellofemoral syndrome sufferers found that core strengthening reduces pain and improves dynamic balance. Improvements in dynamic balance increase stability in the lower limbs with movement, thereby placing less stress on the patellofemoral joints. If you have a mild case, you can do quad and core strengthening exercises at home. It’s a good idea to have your knees assessed by a health care professional and let them recommend the most appropriate exercises for you. If you have discomfort after a workout or between workouts, apply an ice pack to your knees.
Foot orthotics may also help. These are inserts you place into your shoes to help stabilize your feet and ankles. They may be particularly effective if you have pes pronatus or a rearfoot eversion. You can buy orthotics at drugstores, although having a custom one made is even better. One way they work is to prevent excessive pronation, or turning inward, of the feet. When you pronate your feet too much, it increases dynamic knee valgus and places greater force on the knee joint. Orthotics help to correct excessive pronation.
The Bottom Line
Patellofemoral syndrome is one of the most common causes of knee pain in the front of the knees and discomfort with squatting is a classic sign of this condition. But don’t guess as to what’s causing your knee pain! Get it evaluated, especially if you have persistent pain or other signs like knee swelling or the knee gives way or locks. Always get an evaluation after a knee injury. Take care of your knees by keeping your quads strong and by identifying any postural problems of foot issues that could contribute to knee pain.
American Family Physician. Volume 99, No. 2. January 15, 2019.
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