Hemophilia is a familial blood disorder transmitted principally through females, who themselves generally escape. The first manifestations usually appear in childhood, and the affection is rare after adolescence. Death is the usual outcome. An attempt has been made to distinguish a spontaneous and a traumatic form of the disease, but it seems probable that traumatism occurs in all cases, perhaps slight and unobserved at times. Gangrene is a not uncommon complication, being attributable to the pressure exerted by extravasations of blood on the surrounding tissues. Hemorrhage sometimes takes place into a joint, and the blood may be absorbed or a panarthritis may result, with deformity and ankylosis.
The etiology of hemophilia is obscure. The hemorrhage has been referred by some to a disproportion between the relatively large amount of blood and the capacity of the vessels; by others to their small caliber and the delicacy of their walls and to