into mature collagen or the collagen develops abnormally. This causes immature and coarse bone formation and thinning (Loeb, 755).The signs and symptoms of OI vary greatly depending on the type. The most commonly used classification is the Sillence (type I to IV). Type I is the mildest form of OI and is inherited as an autosomal dominant trait. The sclerae (middle coat of eyeball) is distinctly blue. Type I is broken down into IA and IB -- the difference being whether dentinogenesis is present. IA has a life expectancy nearly the same as the general public. The physical activity is limited, and may appear to have no disability at all. The bones have a mottled or worm like appearance, forming small islands (Isselbacher, 2111).Type II is lethal in utero or shortly there afterbirth. The survivors live from just a few hours to several months. The karyotypes of parents are usually normal. This type is broken down into three subgroups: IIA is characterized by a broad, crumpled femora and continuos rib beading, IIB by minimal to no rib fractures, and IIC by a thin femora and ribs with extensive fracturing. While in the uterus, there is poor fetal movement, low fetal weight, poor ossification of the fetal skeleton, hypoplastic lungs, the long bones of the upper and lower limbs are shortened or deformed, and the head is soft. Intrauterine fractures occur, and death is usually from intracranial hemorrhaging due to vessel fragility or respiratory distress from pulmonary hypoplasia. The bones and other tissues are extremely fragile, and massive injuries occur in utero or delivery. The ribs appear beaded or broken and the long bones crumpled (Isselbacher, 2111). Type III and IV is intermediate in severity between types I and II. Type III differs from I in its greater severity and from IV in that it increases in severity with age. It can be inherited as either an autosomal recessive or dominant trait. The sclerae is only slightly bluish in inf...
