Ive stuck to riding this spring. Been riding the same setup for two years, no recent changes. All of a sudden, Tuesday, my knee starts hurting towards the end of my ride. Its like the inside of my knee, the area where quad creeps around the side of your knee cap. I can point to exactly where it hurts. I of course went out and rode hard Wednesday, and the end of my ride, my knee was killing me. I iced and took ibuprofen the past two days and its feeling better. It doesnt really hurt when I walk, but I can feel it when I take stairs - similar motion to cycling.
So what say you arm chair doctors? Whats my diagnosis? What is my treatment?
I really want to do a circuit race tomorrow!
(and yes I searched, seems all knee pain on ST is ITB)
I’m far from a doctor but it could be Patellofemoral Syndrome. http://en.wikipedia.org/wiki/Patellofemoral_pain_syndrome
It’s common that PFS could flare up towards the end of a bike and that the stairs hurt. “IF” it was PFS your bike fit could be part of the problem. I think the general rule of thumb is front of knee pain means your seat is too low and back of knee pain means your seat is too high.
Have you had a bike fit?
Like I said I’m not a doctor or a bike fitter so I’m simply guessing. At least you have something to look up 
Injuries suck. Hang in there. I hope you are feeling better soon.
I have not had a bike fit. Knee pain is more on the inner side of the knee. My seat has been at its current location for a year. Good thought on the diagnosis, Ill read up more on it. Any other thoughts out there?
Had a run of pes anseritis last year when training for my first 70.3 distance race. My symptoms were similar to what you described earlier-No pain with running (for me), no pain with shorter rides but very sharp+localized pain medial (inner) knee near the end or the ride. You could try reading up on in a bit and see what you think
http://emedicine.medscape.com/article/90412-overview
Very well could be PFPS as previously mentioned-Good Luck!
Definitely sounds like PFPS is it.
What was your treatment / recovery like? Do you think I’d be alright running?
Ill give this another shot. You could have a patellar tracking issue. Sometimes the vastus medialis begins to shorten with more strenthening to the quads which sort pulls the knee cap to medial side just enough to aggravate the patellar tendon causing pain. Some of the newer taping techniques can help correct this issue. There are some exercises that you can find to assist with correcting that issue.
DUKE