I never noticed until we got Mr.Beefy or well until he got us lol. That english bulldogs have different structures. My neighbor has two males and they look totally different, one has a very straight back and the other has a small arch. Mr.Beefy has a higher arch which kinda freaked me out when i went to pick him up. But the vet said English Bulldogs by AKC standard are suppose to have arches. So does your bully have an arch or straight?