The splayleg disease: a form of congenital glucocorticoid myopathy?

In countries with modern pig industries an increasing percentage of newborn piglets is affected by congenital myofibrillar hypoplasia, also called splayleg or spraddleleg. The main pathomorphological features of this disease are myofibrillar hypoplasia and degeneration. Glucocorticoid myopathy induced in immature muscles of early postnatal rats and rabbits has a pathomorphology very similar to that of splayleg disease. Also in other respects the splayleg disease resembles the glucocorticoid myopathy, as summarized in this contribution. It is suggested that splayleg might represent a congenital form of glucocorticoid myopathy resulting from stress and hormonal imbalance of pregnant sows which affect the fetuses.