if so how long we looking at?
Dunno, would depend on a lot of things. If the operation is needed or not, but I think one-two months for full recovery at worst case scenario.
But this is just a wild guess from me and hoping for the best.
I have had injurie to my knee in a similar circumstances as did he, and I had to go to therapy and was out for a whole year, fully got back after another 3-4 months or so... Let's just hope it's not that serious.