50% Medial Meniscus tear in Fall of 2005 when I was 67. Had surgery and started Physical Therapy once my Dr gave the OK. Also after working on the tear he scraped alot of arthritis out of the knee. I was able to start hiking before the New Year mainly on level trails and avoided any steep climbs for a while. Started climbing 14ers in Spring and since 2005 have summited 33 with no knee problems although I wear a knee brace as a precaution.
You might discuss with your Dr if you need any arthritis scraping while doing the surgery repair to the Meniscus.
With a good PT program and not rushing back into your workouts I am confident that you will recover well and be back climbing as well as you were prior to the Meniscus tear.