If its your outer knee its probably the IT band and a patellar strap wont do you any good. Best to get a foam roller and start working the outside of your thigh. Patellar straps are for patellar tendonitis and that pain pattern is from the bottom of the knee cap to the top of the shin, right in the middle.
Oh, and its probably rubbing the fibula.
[This message has been edited by Kjodie (edited 3/25/2013 9:32a).]