I have a lot of experience with knee problems: tore the ASL and tore and wore down the meniscus such that my new PT asked if I had had a meniscectomy in both knees. No. In sum, ice, rest and ibuprofen is needed in the acute phase of an injury, but as soon as is possible, exercise and keeping the knee strong is the key. PT: Bought a stationary bike and first exercise was cycling with no resistance: this helps to keep the joints and fluid in the knee moving. Then gradually add resistance. Also a program of knee strengthening, up to eccentric drops holding onto weights. I start each dance practice warming up my knees with parallel plies of varying depths and speeds. Make sure all this exercise is done with the knee over the toes; no twisting. This is my new life but the muscles around my knee are strong and allow me to dance with no meniscus in either knee. Took a couple of years, but my knees are pretty good and and I can walk down stairs now pain free although I can't jump from a great height. Dancing open latin, and jiving is no problem. If I skip my knee strengthening exercises, I feel twinges, which is the message to get back at it.