I'm not sure what doggie diapers look like but we have used little boy's underwear/briefs on our dog backwards so her tail (stump) could stick out.
Boy Diapers and Belly Bands - Little Dog Fashion
Oh, boy. That’s a tough situation. My only suggestion is to work with your veterinarian on pain control for your dog. The pain is probably why he is acting aggressive when you try the diaper. Maybe if he didn’t hurt so much, he would be better about having a diaper put on.
boys love puppy dog diaper cake theme diaper cakes.
Pro: Much less expensive than official dog diapers. I spent about $5 on 3 pair of boy’s underwear, and I can get 40 of the store-brand pads at Wal-Mart for about $9.
Diapers For Male & Female Dogs | Male Dog Wraps | Petco
Generally, diapers are for female dogs, belly bands are for male dogs. Some male dogs can wear diapers, but it is important that the boy parts are covered completely by the diaper he’s wearing. So, you would want to measure from base of tail to past his boy parts and make sure that the diaper’s bottom part is long enough to cover the boy parts. When in doubt, go with the which has a bottom flap covering the boy parts.