I have only had one session where I learned that a lot of my scar tissue in my leg is not new. It formed the past few years that I had delayed surgery and favored my good knee. The scar tissue related to the knee replacement is new. The doctor treating me told me I needed to get rid of the swelling before she could really tackle the scar tissue so she went pretty gentle the first session. It was not painful. She rolled a heavy plastic piece of equipment gently over my entire leg - both front and back of the leg - from ankle to thigh. She did indicate that she would gradually rub that tool deeper and deeper into the tissue to break up the scar tissue on subsequent sessions. After that session she put me on an ice machine where ice cold water ran thru a leg wrap that was also a compression wrap to assist in reducing swelling. Let me get a few more sessions under my belt and I will get back with you to let you know how it is going.