Common Causes of Anterior Knee Pain
Knee pain is one of the most common areas of complaint from people of all levels of fitness. If you have not experienced knee pain yourself, then you probably know someone who has. Knee pain presents in a variety of ways – sharp, dull, achey, unstable, stiff – and in various areas of the knee – front (anterior), back, inside, outside, above, below. In this article, I explain some of the more common causes of anterior knee pain, including Patellofemoral Pain Syndrome, Patellar Tendonitis, Pes Anserine tendonitis/bursitis, and Osgood Schlatters Disease (primarily a youth condition); and finally, in Part II, I provide helpful tips for prevention and treatment.
Patellofemoral Pain Syndrome (PFPS) involves irritation of the cartilage under the kneecap (patella), as it interacts with and contacts the bone beneath it, called the femur. Early on, pain may be associated with inflammation or softening of the cartilage, but as compression continues and the cartilage breaks down, arthritis may eventually develop. Pain may be vague in location or appear to move around, but is generally localized to the medial or lateral side of the kneecap. Quite often, there are multiple factors that contribute to PFPS, which may include some of the following: tight iliotibial band (ITB), hamstrings, or quadriceps muscles; patella resting in a lateral tilt position; weakness of the gluteals and deep hip stabilizing muscles; or altered timing of quadriceps muscle activation, resulting in abnormal tracking or pressure on the patella. PFPS generally continues to worsen until the appropriate factors are addressed and normalized. Look for a future article from me on Patellofemoral Pain Syndrome - it is very close to my heart, as I have a personal history of this type of knee pain and have successfully managed it.
Patellar Tendonitis consists of inflammation and irritation at the upper portion of the Patellar Tendon,
which is in the front of the knee and attaches the kneecap (patella) to the lower leg bone (tibia). Pain is often felt at the lower tip of the kneecap and into the tendon below. The knee may feel tight, initially, and painful when running downhill or descending stairs. In early stages, the pain may subside after warming up, but eventually the tendon breakdown will worsen, causing cellular changes and degradation of the tissue. Contributing factors may include tightness of the hamstrings and quadriceps, lack of eccentric quadriceps strength, and poor shock absorption and landing control from the core, hips, and lower extremity. Improper training progression may also contribute by increasing the demand on the tendon faster than the body can develop appropriate tolerance.
The Pes Anserine is the conjoining tendon of three muscles that cross the medial knee and attach to the front/inside of the upper tibia. These three muscles (Sartorius, Gracilis, and Semitendinosus) work together to control abnormal rotational movement at the knee. Poor stability at the hip and foot, combined with increased running or training, are often the culprits of Pes Anserine tendonitis or bursitis. The pain is localized over the anteromedial lower knee and may be tender to the touch.
Osgood Schlatters Disease usually strikes adolescents during a growth spurt, when bones are lengthening faster than muscles. More specifically, Osgood Schlatters Disease involves irritation of the patellar tendon attachment to the lower leg, at a boney prominence called the tibial tuberosity. When the bones are growing rapidly, the patellar tendon pulls on the tibial tuberosity, causing pain. The risk is greater if the child is also participating in a sport or activity with a lot of jumping, running, and changing directions. The tibial tuberosity may become enlarged and tender to the touch. The condition may resolve on its own in 1-2 years, although improving lower extremity flexibility, specifically the quadriceps, will be beneficial in reducing the force, decreasing pain, and resolving the issue more quickly.
Patellofemoral Pain Syndrome, Patellar Tendonitis, Pes Anserine Tendonitis/bursitis, and Osgood Schlatters Disease are all unique conditions and should be treated as individually as the person who is experiencing the pain. With that being said, however, there are common findings that, when addressed appropriately, will help to resolve the issue and get the athlete back to full activity.
Ideally, these injuries will be avoided by maintaining good flexibility, strong hip and core muscles, good biomechanics, supportive shoe-wear, and with proper warm-ups and training progression. However, when knee pain occurs, it is important to get an appropriate diagnosis and start treatment early to resolve it and minimize the chance of recurrence.
Manage and control inflammation immediately if the injury is in an acute state. For details on how to control acute inflammation, click here. We recommend that you ice the knee over the area of pain after activity or at the end of the day for 15-20 minutes.