I have two personal pups who have had FHOs and I have had a few fosters who had it. The surgery does sound barbaric and I was totally horrified when it was suggested to me the first time. I did a lot of reading and speaking with people about it and went ahead with it even though it just totally creeped me out. The day after surgery, I opened my back door to let some pups out thinking I would put a leash on this little one who had the surgery...he RAN out the door. I remember standing there in shock!
They really do well after this surgery. They don't have the restrictions that they have after other ortho surgeries because there really isn't much to *undo* I suppose.
I think you will be pleasantly surprised...and your baby will soon be out of pain.