Suggest Treatment For Pain In Shin Due To Injury

I have an old injury to me left shin. I fell and hit it hard on a stone wall 20 years ago - it was very swollen at the time and a&e strapped it up. Still causing me pain when i run and it has a large swollen area just below the knee which i have had since the injury. can i do anything to help it? i am 37, 5ft 6in and weigh 13st 9lbs.