need advice

[crazychopper]

my 5 year neutered nale boxer recently has become aggressive towardds other dogs. Just to give you some background he recently had 2 different orthopedic surgeries in the lst 2 years. Im a vet tech so he has been to the hospital many times so just hang out. But in the last 6 months he went after 2 dogs one the other dog was very dominating and the other was a very submissive basset hound. The last year he really has not been able to play with other dogs b/c of his surgeries. I just want the fun loving dog loving guy I used to have