Radiological Anatomy of the Shoulder, Elbow and Carpal Joints in Southern Giant Pouched Rats (Cricetomys ansorgei)

Radiography is frequently used for the evaluation of the musculoskeletal system in domestic and wild animal species. The aim of the study was to document the radiological anatomy of the shoulder, elbow and carpal joints and to provide length measurements of selective forelimb bones in southern giant pouched rats. Forelimb radiographs were obtained in seven adult male and female southern giant pouched rats under general anaesthesia. All rats had a well-developed clavicle, coracoid process and acromion. The minor and major tubercles were located further distally relative to the head of the humerus. The medial epicondyle and lateral supracondylar crest were very prominent. The supracondylar foramen was present in all rats. The radius was relatively smaller than the ulna, and the interosseous space was wide. The carpus had eight carpal bones, and two rudimentary digits were visualised on the palmar side of the manus. Additionally, five slender, widely spaced metacarpal bones, were seen with the third metacarpal bone being relatively the longest and the first metacarpal bone being the shortest. Shoulder joint dysplasia was identified in one female southern giant pouched rat. Radiographic examination of the thoracic limb in southern giant pouched rats allowed evaluation of bones forming the shoulder, elbow and carpal joints. Current information will contribute to the understanding of rodent anatomy and will be useful for scientists researching the forelimb of rodents and related species. Additionally, this information will augment the application of radiography and other related diagnostic imaging modalities in rodents and hence will enhance their welfare.