I had a young ewe that twisted her back in her first labour when she chose a ditch for giving birth and rolled down into it.
Nothing could be done and it was suggested she was put down after three days but I called my McTimoney chiropractor out - he got her up adjusted her spin. She gave a grunt and went out to start grazing.
Gave birth unassisted to twin lambs next year, same year after, then she was sold on. At the time the callout change for the chiro was the same cost as the vets bill would have been