Closed population of 6 generations Duroc pigs was selected for higher productivity and better leg soundness. The leg joint lesions of 174 slaughtered pigs at approximately 90kg live weight were scored from 0 (no lesion) to 4 (very severe lesion) in optical, radiographical and histological standpoints throughout the six generations. Moreover, one thousand and three hundred eighty three pigs were scored from 1 (very good) to 5 (very weak) for leg weakness. Significant differences in the leg weakness score and joint lesion scores were observed among selected generations. Significant differences were observed between gilt and boar/barrow group in 9 traits. The heritabilities of joint lesion scores were low through intermediate. The heritabilities of histological joint scores were also low through intermediate. The phenotypic and genetic correlations between the scores of front (humerus and ulna) and rear legs (femur) were low. The genetic correlations between optical, radiographical and histological scores of the same joint were generally high. The phenotypic correlations between the leg weakness score and joint lesion scores were positive although statistically not significant from zero. The genetic correlations between the leg weakness score and joint lesion scores were generally intermediately or highly positive. The result suggested that selection based on joint lesion scores could lead to a better leg joint condition optically and histologically. It also suggested that selection based on leg weakness score could lead to the reduction of leg joint lesion according to the correlated response.