Gross Morphological and Osteometrical Evaluation of the Lumbosacral Ve r t ebrae and Pe lvi c Bone s of New Zea Land Rabbi t (OryctolagusCuniculus) and their Clinical Applications

This study examined gross morphology and osteometry of vertebrae [lumbar (L), sacrum (S) and coccygeal (C)] and pelvic bones of male New Zealand white rabbits (Oryctolaguscuniculus) and their clinical relevance. Ten healthy male rabbits weighing between 2.8-3.2kgwere used. The animals were sacrificed and their bones processed using standard methods. Gross morphological features of the vertebrae and pelvic bones were described and standard osteometric variables of lumbar, sacrum and coccygeal vertebrae and pelvic bone also determined. Results showed the lumbar vertebrae to be seven, with spinous and transverse processes that decreased in craniocaudal manner. The sacrum was fused, with the first three cranial sets bearing conspicuous spinous process oriented in different directions. The pelvic bone was rectangular consisting of ilium, ischium and paired pubic bones united by a symphyseal joint. The coccygeal bones numbered up to sixteen. Remarkable osteometric findings include: significantly decrease (p<0.005) vertebral body length in L and L ; increased transverse process of L L and 6 7 4, 5 L ;reduced spinous process length in L L ;decreased coccygeal vertebral body length in C C and increased 6 1- 3 13- 16 coccygeal vertebral body diameter in C . Osteometric variables on pelvic bone were not significantly different 1 (p<0.005). The study demonstrates morphological and osteometric variables of the vertebrae; between last lumbar and first sacral (lumbosacral joint) and junction of conusmedullaris, and may form the basis for clinical, surgical and anatomical maneuvers in this animal, especially to access the subarachnoid space for cerebrospinal fluid or injecting local anesthesia and therapeutic substances into the epidural space.

Key Words: gross morphology, osteometry, lumbosacral, pelvic bone, Oryctolaguscuniculus