Epiphysiolysis, a possible cause of limb deformities in lambs.

The process of enchondral growth of long bones of four three month old lambs raised in total confinement and showing bowed forelimbs was investigated. The results, based on radiologic, histologic, and fluorescence microscopic examinations were compared to findings made in four age-matched controls. The principle finding was that the transition from cartilage cores to primary trabeculae at the growth plate was deficient. In two instances a slipping of the distal radial epiphysis and in one instance a slipping of the metacarpal epiphysis was found. In the others, evidence of a healed slipping was present. It is postulated that the slip is responsible for the deformity.