Why Is The Skin Post Achilles Tendon Tear Not Healing?

I tore my Achilles tendon four years ago and it is still not healed. I have seen at least 35 doctors and currently am seeing one at Joseph M. still Burn Hospital here in Augusta, Georgia. The tendon healed but the skin has not. He has clipped fiber wire from the incision area four times over the last several months as it has worked its way out of my leg. I am at wits end because no one really knows an answer. They avevavoided going back in because of more scar tissue. Help.