Thank you all for your good wishes. The ewe is up and walking and grazing, which is good. The outcome won't be clear for a few days when we will find out if any infection has occured.
A section wasn't a feasible option in a dark muddy field shelter on a ewe who had been fighting for three hours and was very weak. The primary concern was trying to get the lamb out before the ewe died of shock or exhaustion, the tear not being inevitable, just a side effect of fused limbs etc.
In a perfect world ,with hindsight a lot of our decisions might be different!!!!!!!!!!!!!