Qualitative, Semiquantitative and Quantitative Diagnosis of Osteochondrosis in Pigs by Computed Tomography (CT)

Post-mortem computed tomography-investigation were carried out on front legs of 126 culled boars from a performance testing station and 202 gilts from a sib testing station. Distal parts of forelimbs were scanned by a whole-body computer tomograph. CT images of normal distal ulnar growth cartilage and metaphysis as well as CT signs of osteochondral lesions are described. The severity of pathological bone lesions was evaluated semiquantitatively (by scoring). 36% were normal, 18, 25 and 21% had small, medium and large lesions respectively. Boars had higher frequency of lesions (80%) than gilts (53%). Two methods of quantitative expressions of osteochondral lesions based on X-ray absorption values were developed. Repeatabilities for the diagnosis methods were from 0.94 to 0.99. Correlations between the different types of diagnosis were in the range of 0.73 to 0.88