Fig. 2

Spontaneous development of joint damage in the commercial pig. a Median total and joint compartment chondropathy score of femoral condyle and tibial plateau joints using Collin’s grading and Revised SFA in juvenile (white boxes, n = 6), adult (light grey boxes, n = 14) and older adult (dark grey boxes, n = 7) pigs. * = p < 0.05; ** = p < 0.01; *** = p < 0.001 significantly different compared to juvenile animals. ψ = p < 0.05 significantly different between medial and lateral compartment within same age group, as determined using Kruskal-Wallis non-parametric test. b Representative images of femoral condyle joints from juvenile, adult, and older adult animals. c Evidence of Grade II and Grade III cartilage lesions in femoral condyles of older adult pigs d Evidence of bony nodules in adult pigs. FCM = femoral condyle medial, FCL = femoral condyle lateral, TPM = tibital plateau medial, TPL = tibial plateau lateral