Imaging studies of the hindlimbs of pacas (Cuniculus paca) bred in captivity

Summary

Objective: To evaluate the hindlimbs of pacas bred in captivity using radiographic and computed tomography (CT) studies.

Animals: Nine mature pacas (Cuniculus paca) 5.9–8.2 kg in body weight.

Methods: Radiographical aspects of the bones of the hindlimbs were evaluated, and the Norberg angle and inclination angle were measured for each hindlimb. Anteversion angle were measured in CT examination.

Results: The bone anatomy of the hindlimb of the paca was similar to that of the guinea pig, apart from two lunulae and a single fabella (lateral) which were observed. The Norberg angle had mean value of 130.56º ±13.81 without any significant difference between testers. Inclination angles ranged from 142.44º ±4.82 to 145.44º ±4.09 by Hauptman’s method, and from 144.94º ±3.13 to 148.22º ±3.25 by Montavon’s method, for right and left hindlimbs respectively. Average values for the anteversion angles measured with CT ranged from 28.56º ±5.56 to 32.91º ± 2.62.

Clinical significance: The data may be used in future studies comparing the paca to other rodent species. In addition, the paca could be used as an animal model in orthopaedic research.

Keywords

Joint angles - rodents - orthopaedics - computed tomography - pelvic limb

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