I had my right knee replaced 2 years ago when I was 67. It was so bad I missed hunting season that year. Doctor told me most important thing was to do exercises that he gave me starting 6 weeks before surgery to make all the muscles in my knee strong. My surgery came out really good. I never used a walker or cane after 3 days. Did physical therapy twice a week for 5 weeks plus all the exercises they told me to do at home every day. I did a lot of walking, since it was November I would go to Home Depot to walk so I did not have to walk in rain. Was driving after 10 days. I was almost totally healed and doing most things after 12 weeks. All stiffness gone after 12 months. I think really important to do lots of exercise before surgery.
