PERIOSTITIS

Help someone please. I have had almost every injury in running possible, but I am now 27, and have had only one problem plague me for the last 5 years. I have poor flexibility, tight calves, etc. Every time I get to 30-40 miles and/or start doing speedwork I get the same pain along the inside of my right tibia-starts at the ankle and eventually gets higher up the periosteum. Gets to the point where when I am stretching it feels like it is pulling along the bone and if I don’t stop ends up feeling like a stress fracture in the ankle but the whole periosteum becomes very sore to the point that I can’t run and it sucks to get rid of outside of sitting for atleast a few months. I don’t ever feel any numbness in my feet or legs ever or much as far as compartment syndrome symptoms-its just this damn periosteum. I have as legit orthotics as I can get from a well respected running orthopedist. I have had several MRI’s, I have no stress fracture, haven’t had one in 5-6 years and no other injuries besides this. It keeps happening to me and it is soo frustrating. Anyone that can pleaseee help me with this and/or recommend a way to get rid of this would have my undying gratitude. I have serious talent but no way to develop it because of this. I would put your kids through college if you could help me get rid of this.