Knee pain in running athletes is extremely common. In fact, over 42% of running related injuries involve the knee according to a 2002 study in the British Journal of Spots Medicine. Consequently, nearly 25% of runners develop knee pain each year.
Patellofemoral Pain Syndrome (PFPS)
Patellofemoral pain is the most common cause of anterior knee pain in running athletes. In the past, the condition was thought to be related to a patellar tracking issue. However, researchers now believe it is more likely related to lack of control of the femur. Importantly, researchers have visualized on MRI femoral adduction rather than lateral patellar displacement. That is to say, it’s a femur problem rather than a patella problem and suggests hip focused rehab.
Potential causes of patellofemoral pain:
- Inflexibility to quadriceps muscle
- Femoral anteversion / glute weakness: diminished hip abduction and external rotator strength
- Excessive frontal plane knee motion: lack of control of knee in sagittal plane
- Potentially, excessive pronation: may cause more frontal plane knee motion
IT Band Syndrome (ITBS)
Iliotibial band syndrome is the most common cause of lateral knee pain. The IT band helps provide stability to the knee at foot strike. In fact, important muscles such as glute maximus, medius, and tensor fascia lata have attachments to the IT band. Generally, symptoms in the lateral knee arise due to diminished hip strength and endurance .
The development of ITBS appears to be related to increased peak hip adduction and knee internal rotation, which increases strain at IT band and causes it to compress against lateral femoral condyle. (Noehren, Brian et al., Clinical Biomechanics)
What can you do about it?
In conclusion, there is good news. Both patellofemoral pain and IT band syndrome are treatable! With that in mind, runners should focus on a few key areas to get the best results:
- Hip strengthening / dynamic control of the knee
- Lower extremity joint motion / alignment
- Running modification: 5-10% increase in cadence can have a dramatic effect.
- Training volume management / appropriate rest and recovery
- Footwear selection
Be sure to check out the 10 Commandments for Runners.