Actually, If you look at the GSD standard, From the AKC website "Topline-- The withers are higher than and sloping into the level back. The back is straight, very strongly developed without sag or roach, and relatively short." In other words, the back should be level once you get past the withers (shoulders).
American Shepherds are not usually "working" shepherds. They are the "showline" shepherds. And yes many have hip issues. Because the German breeders are required to x-ray hips and elbows. You end up with less of a chance of hip issues if you breed dogs with good hip ratings. Showline shepherds are bred for the "stance" Not sure if you know what a "stack" picture is so look at this working line german import http
/www.pedigreedatabase.com/gsd/pedigree/464174.html and then look at this showline http
/www.pedigreedatabase.com/gsd/pedigree/605875.html GSD's have a fluid gate when they move. Showlines are bred for nothing but the "gate" and the "stacked stance" because that is all they have to do. There are "german showlines" but they are still flat relatively flat backed and they must have "working" titles (Shutzhund)
White and "panda" are faults and not "supposed" to be bred in Germany. The only colors the standard allows is black, black and tan, black and red, and sable. Long coats are also considered a fault and not supposed to be bred. There are breeders who breed for those colors and coats. Usually black and red denotes Showline.
*EDIT*
Hip problems and elbow problems can also be environmentally created. Too much running and jumping at too young of an age can cause problems. As can bad diet. We make it a big issue when we sell pups. Normal running (normal playing for a pup, not playing fetch for hours) is ok. Taking your 6 month old pup out for a 5 mile job is a no no. And absolutely NO jumping until the dog is fully developed.
American Shepherds are not usually "working" shepherds. They are the "showline" shepherds. And yes many have hip issues. Because the German breeders are required to x-ray hips and elbows. You end up with less of a chance of hip issues if you breed dogs with good hip ratings. Showline shepherds are bred for the "stance" Not sure if you know what a "stack" picture is so look at this working line german import http


White and "panda" are faults and not "supposed" to be bred in Germany. The only colors the standard allows is black, black and tan, black and red, and sable. Long coats are also considered a fault and not supposed to be bred. There are breeders who breed for those colors and coats. Usually black and red denotes Showline.
*EDIT*
Hip problems and elbow problems can also be environmentally created. Too much running and jumping at too young of an age can cause problems. As can bad diet. We make it a big issue when we sell pups. Normal running (normal playing for a pup, not playing fetch for hours) is ok. Taking your 6 month old pup out for a 5 mile job is a no no. And absolutely NO jumping until the dog is fully developed.