Sphynx cats are 'shaped' differently from most other breeds of cats. Even if one only had a minimal understanding of cat morphology, the skeletons of a Persian, a Maine Coon, and a Sphynx would be sufficiently different to allow a an easy guess as to which was which. While cat breeds don't show the radical range differences in shape and size found in dogs, there are differences that can be seen. Sphynx cats have distinctly longer legs, and when they sit or squat in that 'cat loaf' pose, their legs assume different angles than many other cats. Because they have so little fur, nothing hides the unusual angulation. Personally, I'd wager the kitten in the middle had its legs 'placed' further apart from its body, although I'm not sure why the cat would be posed that way.Just think about how pugs, Frenchies, and English bulldogs can slide into that "frog dog" pose and a greyhound can't - and vice versa, how pugs et.al. can't assume the 'laying down sphynx' position that sighthounds can. Just an issue of morphology.
So in other words, these cats are not deformed, and the one in the middle in particular is NOT dysplaying the carpal laxity syndrome that you so often see in super fugly bullies.