Dog not urinating

Question
Yesterday my 98 pound American Akita was hit by a car - his back right leg is broken - upper limb.  The vet gave him a shot, did not splint or bind the leg.  This was around 4 PM yesterday.  He is lying comfortably but he has not urinated.  We have carried him outside (he is house trained) twice and this did not do the trick.  He can not get up on his hind legs.  Is there something we can do to possibly help him urinate?

Answer
Cynthia;
He needs to go back to the VET asap!
He may be shutting done...in renal failure!
You could lose him..
Serious!
If it is just that he is in pain, you still need to go to the vet, as they can give him Rimadol!
Like aspirin for dogs...and he may need an anti inflammatory!
So, take him in asap.
Giving him something else right now not under a Vet's supervision would not be prudent!
Better times!
Melissa