Morphology and function of ankylosaur dinosaur limbs are explored and analyzed using comparative morphology and finite element analysis. Reconstruction of the forelimb and posture of Pinacosaurus grangeri matches well with trackways attributed to ankylosaurs. A flexed humerus angled away from the body, perpendicular radius and ulna, and upright metacarpus forming an arch proximally result in a crescent configuration of the manus, and a semi-supinated posture relative to the main axis of the body. The ankylosaurid metatarsus has a twisted proximal articular surface, metatarsals being optimally adapted for bearing weight at increasing angles, from medial to lateral. Metatarsal counts of Thyreophorans and other basal ornithischians do not match well with currently accepted phylogeny of these taxa, indicating that a revised phylogeny should be considered. Finite element analysis results, the twisted proximal articular surface, and other morphological features support a rolling motion in the foot while pushing off in locomotion. This is perhaps an adaptation to cope with the wide hips of ankylosaurids, bringing the pes closer to the midline of the animal during locomotion to increase maneuverability.