It is the most common injury when someone says a knee sprain. There are grades 1,2,3 for an MCL injury. Grades 1 and 2 don't require surgery and just need rest. Both can be played on with a brace within a week or two. Grade 3 usually means complete tear and needs surgery. The MCL has the best blood flow and therefore can heal itself better than the other 3 ligaments in the knee.
In this situation it's the meniscus that would be the reason for surgery. Depending on location and type of tear determines whether they shave it down or try to repair. Meniscus has poor blood flow so often repairs don't work. If they go in for meniscus it would definitely be 4 weeks or more.
Also there is often no need for a brace just waking around with an MCL sprain. Really only need brace on athletic events.
[Post edited by cush13 at 01/22/2019 2:14PM]