I am doubtful that a thirty year old, fairly benign injury, which has never caused symptoms, is suddenly the cause of problems, What you are describing sounds like
tibia vara, or a bowed
tibia, probably unrelated to the old hematoma.
I wonder if a comparison xray was taken to see if the deformity is present in the "normal" leg. Other possible causes of pain are a stress fracture, shin splints, or an arthritic knee.