Re: My turn for advice
This is from my overly-fit, health nut freak of a friend:
First, by no means take these ideas as anything other than brainstorms from my experience as a bicycle racer.
1)Have your blood pressure and pulse taken at the ankle. Runners and cyclists tend to have different blood pressure readings in the legs than in their arms because of increased vascular fitness. The test for normal people is called something like Peripheral Circulation, and it is to better identify risk for heart attack. The change in blood pressure could affect your bodies ability to move the damage blood cells, thus the swelling.
2)Have you had any knee or hip problems in the past? Injuries can trickle down through compensation.
3)Have a fasting blood sugar test done. It could be a very mild form of Diabetes that would go unnoticed until high need for Glucose. Extremity swelling is a symptom of Diabetes.
My advice is don't mess around with a normal pediatrist or orthopedist. You need to find one specializing in sports medicine, or they are going to miss stuff. Just my personal experience. As a fit athlete, your symptoms and diagnosis are going to be a lot different than a normal "healthy" person.