I had an autograph done on my acl six months ago, the tendon was taken from my hamstring. But still today I continue to have stiffness in my knee. Especially if I am sitting for more than five minutes or when I get up in the morning, my knee is really stiff which causes me to limp. Also I still haven't regained full extension or flexion, I am short a few degrees in comparison to my good knee. And the biggest concern I have is my knee makes a loud grinding/snapping sound when I straighten it out. It occurs without fail every time, at the point where I get my leg as straight as I can, and the feeling is very uncomfortable and sometimes painful. The sound/sensation seems to be coming from the inside of my knee, I can't feel anything abnormal from the outside. My surgeon seems not interested in my problems and says its just scar tissue build up, but it just doesn't feel normal. The sound gets louder depending on how much force I put into straightening my leg. Are these normal symptons of scar tissue build up? I used to be a pretty athletic person, and six months post surgery I am no where near how I used to be.