Knee Braces

I was hit by a car when I was 12, being tall the car hit me right in the side of my right knee.
I had to wear a straightning brace for a year and a half.
After a while i had no pain in my knee. once in a while but not often.
I do alot of long distance running (and always have) and my knee never usually bugs me however lately i have been getting alot of pain again.
My old knee brace if far to big and constricting for me to wear running.
I am wondering if anyone knows a good brand or style of knee brace i could get.
Thanks,
Justine :0)