I feel for ya bro
I wouldn't think that it would hurt , but if your not going to be rehabing your knee then the other one is going to get bigger , it will get bigger anyhow from working alone and your hurt leg will get smaller from not working at all , so it might exadurate the effect a little.
BRO you realy need to check into getting a EMS unit , you can use it on your hurt leg and it will stop alot of the loss from not useing it.
Ask your doc , he will probably lend you a "tens unit"
and get at least two second oppinions before somebody cutts you
most injuries can be fixed through Ortho Scoppic surgery , there is hardly a reason to cut open you knee anymore but some docs will "usualy older docs" because they arn't familiar.