Anatomy of the hind limb skeleton of the chinchilla (Chinchilla lanigera)

Abstract

This study aimed to document the detailed features of the hind limb bones in chinchillas (Chinchilla lanigera). Twenty chinchillas (10 females and 10 males) were used. Animals were euthanized and X-ray of appendicular skeleton of pelvis was taken immediately. Then the bones were macerated. The iliac wing was considerably long and the gluteal line formed a distinct crista. The sacropelvic surface (facies sacropelvina) was not observed, however, the iliac tuberosity (tuberositas iliaca) was evident. While the average distance between the midacetabulum and the tuber coxae (ventral iliac spine) was 33.58 mm in males and 31.34 mm in females, the average distance between the midacetabulum and the ischial tuberosity was 15.09 mm in males and 17.18 mm in females (statistically non-significant). The caput ossis femoris was bent to medial at an average of 60 degrees angle. The differences in both the width and length of the obturator foramen between males and females were statistically significant (p < 0.05). The third trochanter (trochanter tertius) and the supracondyloid fossa were absent. The tibia and the fibula formed a joint on the proximal and distal parts. The comparative size of the distal tarsal bones were IV > III > I > II (from the largest to the smallest) and the fifth metatarsal bone shaped a small bone. The comparative lengths of the other metatarsal bones were II > III > I > IV (from the longest to the shortest). Three phalanges bones were notable. The proximal phalanx was the biggest of all.