My mom has arthritis in the knee, and she seeks advice. Should she take cortisone injections or undergo surgery? Or neither?

I am about to undergo it in about one month. I have a lot of arthritis in one knee and the pain is realoy bad. I have cortisone injections but due to prior surgery the scar tissue build up has made the injections difficult to adminster. I just want to live pain free and be able to excersise to lose wieght and feel better. Will the surgery enable me to do that?

I have arthritis in both knees, ankles, wrists & elbows. After a year of pain, I finally decided to try cortisone injections in my knees. I am wondering how long they will last.