Suggest Treatment For Swelling And Pain In The Knee

I am 57 years old and injured my left knee snow skiing 6 years ago. I must think constantly while walking, getting in and out of the car. My knee will just give out on a sideways motion. I have fallen down because of it. I am now working a job where I stand 8 hours a day, my knee is constantly swollen cant bend it and very painful. I wear a knee brace and find it hard to get on because of the swelling. The swelling and pain is also in the area below the knee. Its so bad today i cannot bend it and put on my socks. That do u think I take aspirin for Arthritis pain it helps but doesnt solve the problem. I weigh 250 lbs 5foot 8 high blood sugar in the morning