It is very likely that it's the other way around: it's actually your hip that has caused your knee problem. New research-I have been told by couple of doctors and physical therapists-shows that many knee injuries are caused by hip issues, like muscle imbalance, tight hips, etc. etc.
I have L knee issues which stem from hip imbalance that is caused by flatter L foot. Because of all the imbalances, I "over use" my L quads muscle and feel it in/above/around my knee.
I'd do the all of any of the following depending how much riding you do:
1. Get professionally bike fitted
2. Have a physical therapist look at you walk, move, and get his/her opinion on your muscle balance. Get some exercises that work on the specific imbalance that you have and do them regularly
3. Streach regularly
4. Get a foam roller and use it for all your lower body muscle groups-specifically the hip that hurts
5. Get deep tissue massage regularly-at least for the time you are experiencing the pain.
Yeah I know, it would be really nice if we had the resources and time for all of the above...