I had a mare Pretty much turn 2/3 of her sdft to jelly. She was 6months box/pen rest before I hand walking started. She never came back to what we were doing before. She went to be a hacking/dressage horse for someone. Took me 8 months to get her sound.
However I found out that the person I gave her to then proceeded to jump her and blew the tendon again, so she is now with a girl who does just use her for hacking.
I had planned to take a foal and let her recover whilst she carried and cared for the foal but unfortunately circumstances meant I had to rehab her and find a good home. If I had realised that despite full disclosure and a copy of vet records that the next owner despite assurances would try to take her jumping etc I would have done things differently.
It depends on the severity of the blow. My mares was bad.