You will be advised by your orthopaedic clinic whether or not you need to do this with your pet.

If you do need to do it here's what it means:
If bladder & bowel function are present you will have to do what is called
"Towelling Out"
it simply means carrying your dog out with the aid of a towel.

How to "Towel Out" your Dog
This simply means using a folded towel underneath your dogs abdomen -just in front of the back legs - to carry your dogs rear end outside.

You place their lead on as normal so you have control of them at the front, then place a folded towel under their rear end to enable you to carry them outside to do their wee's and/or poos.
It is definetely easier to have two of you to do this if you have a medium to large dog - although it can be done by one. If one of you carries the towel the other holds the lead to guide & restrain them and also to move the rear legs out of the way so they don't get wee'd on or soiled. Also this person can tell the person holding the towel when your dog has done their business.

Alternatively, cut two holes in a large beach towel and drop the hind legs through the holes, holding the towel above your pet's back.