Every fitness professional has worried about this at one point in their career, a client has an injury and you wonder did I do everything I could to avoid that. Well after you think that through and realize that you did everything according to protocol and current standards you realize that you want to express to your client that you are sorry they are hurt but you don't want them to use that against you. What can you do? 

In Canada we have recently seen "I'm sorry" bills being passed that allow people to apologize without the people they are apologizing to being allowed to use that as a tool against them in litigation.

For more info read this article, or check with your local legislators.