What Causes Hematomas And Indentation On Calves After An Accident?

I was rear-ended in a car accident 15 months ago. The driver who hit be was going 60 mph, and I was almost stopped. The adjustment bar under my seat caused blunt trauma to my calves which resulted in severe hematomas. You can still see darkness on my right calf, and there is an very noticeable indentation there as well. It is still very tender to the touch, and that muscle tires after walking about 6 blocks. I have had physical therapy and multiple visits to an orthopaedic doctor. He now wants me to have an MRI done to rule things out, but did not expound on what he wants to "rule out". ANY professional advice would be appreciated!