Hi there and welcome to YT!
My little girl had the surgery for Leggs Perthes when she was 7 mos. old. The surgery went fine. She is 2 yrs and 4 months now and seems to be doing ok. When she runs, she still holds that back leg up but she walks on it just fine. I give her supplements for her joints all the time now... I don't know how much it is helping but it certainly can't hurt.
I hope Denzil heals quickly and is back to his regular self soon!