wow thats is a tough one, how long before you could train again?
A couple of weeks if I remember. The doctor I saw at the time said it was just swelling and would go down, and the physio didn't think there was much wrong. So I trained Karate on it for a couple more years. Every time I'd train really hard for Shodan it would "go" again. Eventually saw a specialist who had a big smile ran out the door and called all the students (teaching hospital) to come and see a really really stuffed knee.
Never was able to go for Shodan in karate because of the knee, and a friend suggested Aikido, best move I ever made.