For the past year or so I have had this condition on my right knee. The symptoms of pfs are; pain whilst squatting on the last 30-35 degrees, swimming breaststroke, also a crunching grinding souund on the last 30-35 degrees of extention. Recently I have been getting a shooting pain sometimes while running when my right foot makes contact with the floor. Also I have noticed that when I try to stretch my IT band it feels like the muscle is coming out of the socket (hard to describe.) Also I have definatley realised that my vmo muscle on the right leg is smaller compared to the left leg especially the muscle around the inside of the knee cap. I have been to the physio a few times and she advised me to strengthen the vmo muscles. Is that all that is needed? It seems impossible to do this without causing further irritation to the knee. If there are any other sufferers out there with this condition I would be grateful for any advice you could offer me.