"Patellofemoral Pain" is another name for pain in the front of the knee, and its a very common reason for adolescent females (10 - 19 years old) to see an orthopedic doctor. It affects from 15-20% of females.
It remains unclear why young females experience these symptoms. There are two theories.
Theory One. Many believe that its due to overuse, when women are overtraining for high school sports. However, by that logic it should equally affect adolescent males.
Theory Two. Others believe that patellofemoral pain is caused by abnormal kinematics (knee motion). Terms such as abnormal "Patellar Tracking", abnormal "Patellar Angulation". Increased "tibial tuberosity–trochlear groove (TT-TG) distance", or increased "hip and knee abduction moments", and increased "lateral displacement of the patella", and "underdeveloped neuromuscular control patterns". These changes cause abnormal patellar tracking and increased contact forces within the knee causing pain.
A recent study directly showed a connection between abnormal kneecap motion and higher risk for patellofemoral pain.
Treatment. The primary goal is to treat this pain with physical therapy and muscle strengthening. These programs work in the vast majority of cases. Sometimes pain or instability persists. In these cases, advanced imaging like MRI or CT scan can be used to make measurements of the knee to determine if the structure of the knee is significantly abnormal. If it is, there are some surgery that can be performed to re-align the kneecap to improve its motion and reduce its pressure on the knee cartilage. These techniques are successful in the properly selected patients.
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