The leg wasn't "perfect" in the sense of being "as good as new". The repair was "perfect" in the sense that it held, the steel plates didn't fail or pull loose from the attachments, the bone showed regrowth, and he put weight on the leg. A bad repair would be a failure of the bone around the attachment points, infection, no regrowth (dead bone), or refusal to put weight on the leg.
The leg was stiff and ugly (and they knew it would be) because the bones around the fetlock joint were so fragmented that they had to bypass/fuse the joint. He basically had no functional fetlock, which is what caused the "slap" that you note in his step. The fetlock is the shock absorber for the lower leg.
He was never going to have a "normal" leg because of the loss of that joint. The question was whether they could get him through a recovery period so that they could bring in the mechanics/prothesis/physical therapy specialists. Sadly, the laminitis developed before they could begin working on physical therapy and strategies to regain maximum mobility.
Wow. You brought up a whole new topic. Joint replacement:’)I didn’t know they were considering that.