Calcification of intervertebral discs in the dachshund: a radiographic and histopathologic study of 20 dogs

BACKGROUND: The purpose of the study was to compare radiographic and histopathologic findings with regard to number and extent of calcified discs in the dachshund. METHODS: The intervertebral discs of 20 dachshunds were subjected to a radiographic and histopathologic examination. The dogs were selected randomly from clinical cases euthanased for reasons unrelated to research at the Norwegian School of Veterinary Science. Lateral radiographs were taken of the vertebral columns after removing them from the carcasses. The histopathologic examination included 5 μm thick sections in the transverse plane, stained with hematoxylin-eosin and von Kossa. Radiographs and histological sections were evaluated independently. RESULTS: A total of 148 (28.5%) calcified discs were identified at the radiographic and 230 (45.7%) at the histopathologic examination. Of 92 discs found to be calcified by histopathology, but not by radiography, the degree of calcification was evaluated as 'slight' in 84 (91.3%). All the intervertebral discs (n = 138) that were found to be calcified by radiography were also found to be calcified by histopathology. CONCLUSION: A sensitivity of 0.6 and specificity of 1.0 for radiography was calculated when using histopathology as the gold standard.