Patellofemoral Arthralgia in Crossfit Athletes
Patellofemoral arthralgia is a very fancy name for pain behind the knee cap, which is a common complaint in the Crossfit athlete. Patellar tracking disorder, patellofemoral joint dysfunction, and chondromalacia patella are all other diagnoses that fall under the category of patellofemoral arthralgia.
Cause of Patellofemoral Arthralgia
Patellofemoral arthralgia is caused by irritation of the tissues between the patella (knee cap) and femur (leg). It was once believed that it was caused by an imbalance between the vastus medialis oblique (VMO) and the vastus lateralis/iliotibial band. The treatment was then directed at increasing the strength of the VMO and stretching the vastus laterialis/iliotibial band.
It actually appears that the irritation is caused by internal rotation of the femur leading to compression between the patella and femur. When bending the knee, there is more compression between the femur and patella which is why movements such as squatting, lunging, and going up/down stairs are painful in those with patellofemoral arthralgia.
Imaging of Patellofemoral Arthralgia
Imaging of the knee is generally not necessary with patellofemoral arthralgia. If an X-ray or MRI was already performed, it may show joint space narrowing or degeneration around the knee. These changes are more closely related to age than they are to pain.
Treatment of Patellofemoral Arthralgia
The main treatment of patellofemoral arthralgia is to strengthen the muscles that control internal rotation of the femur. The muscles that control internal rotation of femur are the gluteals (glute maximus and medius). Strengthening the quadriceps muscles is also useful, although the focus is to strengthen them as a whole not just the VMO.
Manual therapy, such as myofascial release and Graston, to the hips and knees can be helpful to decrease the pain of patellofemoral arthralgia. In addition, joint manipulation and mobilizations can help to normalize the biomechanics which will decrease compression on the patellofemoral joint.