I received my mri results and the doctor said there is scarring from the ankle sprain but the tendons are intact. he wants to do a cortisone shot with lidocaine. if the shot helps whats the next step and if it doesnt help, what could be the problem?

I would not get a Cortizone shot in the ankle joint unless you knew the reason for giving it. It does not sound like a diagnosis has been made therefore you would basically be shooting into the wind literally. I will continue searching for a diagnosis. Seeking another opinion would be beneficial. Initially you did not present the type of symptoms that you are presented with.Has rehab been tried?