Dog behaving badly - ADVICE PLEASE!!!?

A year ago my dog had a serious leg break where his bone shattered into around 12 pieces. He had to be operated on and then penned for close to 8 months. He had the plate removed about 4 months ago and was free to walk around and be active. However, during this time I have noticed his personality alter - he is becoming aggressive towards my other dogs and snappy and starts fights. He has never been an agressive dog in the past so this is concerning me. I am going to take him to the vet for a check up. He is entire, could neutering help, he is 4yrs old or is it a result of the trauma he has been through? Advice would be great!