This demonstrates that multi-segmented bones (eg 20:57) can give problems (at least on a UV-textured model). The right forearm (on pix on the left) is multisegmented, the other has 1 segment. The arms are not rotated to an extreme.
Also see on the ribcage (spine02, multisegmented), which is not rotated or deformed, yet messes up the looks...
