I am not a Dr, but my last job consisted of reviewing medical charts and assigning disabilities for the VA. I was in daily contact with some of our Drs for advice. From rereading your entries, I gather that the only diagnosis you have is for arthritis, as I do, and that you are 62 years old. When I was that age, my wife and I went on a 10 day, backpacking, Dall's sheep hunt in the NW Territories. On one of those days, we got up at sunrise (2AM), hiked all day, and set up camp at sunset (10 PM). I am now 71, and still hike and hunt the mountains of Mt.
My regimen is to take 2 tabs of "Move Free" in the AM (plus 1 in PM when hunting), wear a knee brace, and use a walking stick. The stick is for balance, and to slow you down when going downhill.
My advice for you is to see your Dr for a referral to PT. He will also be the one to tell you the proper time for surgical intervention, as long as he is not knife-happy. The physical therapist needs the diagnosis to be able to give you the proper therapy. There are many different types of knee injuries, and some therapies may not be appropriate for you.
The last piece of advice, and most important, is to buy a Versatile Hunting Dog, walk it daily, and hunt it often . I suggest a Wirehaired Pointing Griffon, as my bitch works slow and close, and holds a good point.
Good luck,
George