Comparative morphofunctional analysis of axial skeleton excluding the skull of primates based on the anatomical, radiographic, and tomographic description of the black-striped capuchin (Sapajus libidinosus Spix, 1823).

Comparative anatomy the basis for studies of evolution, and radiographic and tomographic aspects, as auxiliary methods in the investigation of anatomical particularities, reinforce evolutionary research. Therefore, the aim of this study was to describe the vertebrae, sternum, and ribs of the capuchin monkey (Sapajus libidinosus) by means of anatomical dissection and radiographic and tomographic images. To this purpose, four cadavers were used in the anatomical analysis and five living animals for the imaging exams. The bones were described and compared with data from other primates species found in literature. Student's t-test for independent samples was performed. The vertebral column of the comprises seven cervical, 13 or 14 thoracic, five or six lumbar, two or three sacral, and 23 or 24 caudal vertebrae. The atlas is characterized by three foramina on the wing. The seventh cervical vertebra had a transverse foramen in one specimen. The anticlinal vertebra is always the penultimate thoracic one, the ninth pair of ribs is always the last sternal pair, and the last two are buoyant. The sternal was composed of five or six sternebrae. The lumbar vertebrae showed a bifurcated spinous process. Three different sacral morphologies were observed. The structures identified macroscopically could be well determined through radiographic and tomographic images. S. libidinosus presented anatomical characteristics more similar to those of man and of platirrinos monkeys. The knowledge obtained by macroscopic anatomy and tomographic and radiological exams contributes significantly to comparative evolutionary studies.

Anatomy applied to image diagnosis of the hind limb in the black-striped capuchin (Sapajus libidinosus Spix, 1823).

The knowledge of anatomy and imaging exams emerges as an important tool in the study of evolutionary processes of a species, in the elaboration of diagnosis, and the successful choice of the appropriate clinical and surgical procedures. Therefore, this study aims to describe the osteology of the hind limb of Sapajus libidinosus by means of gross, radiographic, and tomographic images. Four cadavers were used in the macroscopic analysis and five animals for the imaging exams, of which four were eventually euthanized and added to the macroscopic study. For imaging exams, they were kept anesthetized. All bones of the hind limb were documented, their structures were described, and compared with data in the literature from human and nonhuman primates. We have performed Student's t test for independent samples. There was no statistical difference between the sexes regarding the length of the hind limb bones. The coxal bone was largely well described using imaging methods. A small penile bone was present at the tip of the penis and it could be identified by all analysis methods. The femur, as well as the tibia and fibula, were not well portrayed in their proximal and distal epiphyses by radiography (Rx). However, they were well identified on tomography. No third trochanter was observed in the femur and the patella had a triangular shape. All the structures described by gross anatomy of the tarsus and metatarsus could be identified by Rx and tomography. More subtle structures, such as the popliteal notch on the tibia, and the gluteal tuberosity pectineal line and facies aspera on the coxal bone, were not identified by medical imaging. S. libidinosus presented anatomical characteristics that were similar to those of larger New World and Old World monkeys, including man. This suggests it's value as an experimental model for studies in recent primates.