The hips and hind limbs were the most birdlike features of theropods. Animatronic dinosaur manufacturer The hip’s big, platelike ilia bones were long, deep rectangular structures. In paleodinosaurs, they were shorter and less avian. The hip socket was especially birdlike, in that it was deep and rylindrical, with a broad posterior joint surface for the head of the femur. Dinosaur costume for sale The femur and tibia were strong bones, unlike the slender fibula, which was fixed tiqhtlv to the tibia not onlv at both ends, but also a third of the way down its shaft ia aspecial flange of the tibia. Predatory dinosaur knees and ankles were rather simple hinge joints. A very avian detail was an upward projection of the major ankle bone, the astragalus, that ran up the front face of the tibia.
Most birdlike of all was the theropod foot. Narrow and compressed, it was in practical terms three-toed, with toes two, three, and four bearing most of the load (Figure 4-15). The outer digit was reduced to a splint at the ankle, yet it was almost always present and strong. Realistic dinosaur costume It may have been mobile and flipped backward to act as an extra lever between the achilles tendon and the foot. The exception is Awmfmus, in which the splint is fused to the other foot bones. This may be the precursor to the avian condition, in which the outer toe is completely lost. The inner or first toe was even more interesting because its cannon bone no longer reached all the way up to the ankle. In birds that still have this toe (the big ground birds and some others do not) it is fully reversed and points backward. In articulated theropod specimens, it seems less reversed. But, oddly enough, some theropod foolprints show the toe fully reversed. This discrepancy has been little noticed and is unexplained. Perhaps this toe was loose and could rotate forward and backward in theropods. In the paleodinosaurs and herreravians, the inner toe is still complete and unreversed, hence the foot has four complete toes and is not so birdlike.