When I had a hip replacement they checked (x-rayed) my knees and told me I would probably need a left knee replacement in the future. Four years later the joint was bone on bone and was replaced last September.
I can kneel and crawl and the degrees of rotation are the same in both knees. Many people won't be able to kneel or crawl - I am one of the lucky ones. Doing a lot of kneeling is more comfortable with a
Folding-Garden-KneelerBefore the operation I learned a lot of coping skills. Go up one step at a time starting with the bad leg first. Use the good leg to push up one step then lift the bad leg up to the same step then repeat. Going down steps the good leg goes first - still one step for both feet. Also used to lift myself up from a sitting position with my arms.
The last six months or so before the surgery I used a cane. Note that Medicare now requires you to be using a cane or walker before they will pay for the operation.