Runners often obsess over finding their specific diagnosis without asking the more important question- why did this happen in the first place? Pain does not happen randomly. Injuring a left verses a right knee is not a coin flip. There is always a REASON. The body in movement is a system of pulleys, levers and angles with predictable consequences; it is simply not that mysterious.
Discovering the cause of an injury leads not only leads to a more complete recovery, it also prevents future injuries down the road. It is absolutely imperitive to long term performance and general well being.
I use video analysis to evaluate whole body mechanics throughout the running cycle. Multiple angles are assessed and viewed at slower speeds. I look for symmetry, efficiency, and proper joint alignment. I then suggest specific drills, stretches, and strengthening exercises to address any deficits. Performing running evaluations is one of my favorite things to do, especially when runners chose to do them as a preemptive, not just reactive, measure!