Type II Osteogenesis Imperfecta is the most severe form of the disease. Approximately 10 percent of people with OI have Type II Osteogenesis Imperfecta. Type II is usually caused by a new gene mutation. The bones of people with Type II Osteogenesis Imperfecta are extremely fragile and often have severe deformities.

Bones may break even while the foetus is in the womb. Many affected newborns do not live past birth, mainly due to respiratory problems, and those that do have very difficult lives. Infants who survive are severely affected. In recent years some patients with Osteogenesis Imperfecta Type II have survived into young adulthood.

This form of the disease affects as many as one in sixty thousand people. Type II Osteogenesis Imperfecta can be further subdivided into types IIA, IIB, and IIC on the basis of the radiographic features of the long bones and ribs.

Type IIA demonstrates broad and short long bones with broad and beaded ribs. Type IIB demonstrates broad and short long bones with thin ribs that have little or no beading. Type IIC demonstrates thin and longer long bones with thin and beaded ribs. Patients with type IIA or IIC inevitably die in the prenatal period; rarely, patients with type IIB survive into early childhood.

Some features of Type II Osteogenesis Imperfecta includes ...

• Most severe form, autosomal recessive/sporadic.

• Abnormal collagen.

• These are often diagnosed prenatally at the 20 week ultrasound.

• Frequently lethal at or shortly after birth, often due to respiratory problems.

• There are crumpled long bones and beaded ribs.

• Numerous fractures and severe bone deformity.

• Skull is soft and deformed.

• Small stature with short limbs & underdeveloped lungs.

• Sclera is deep grey-blue or tinted.

• Not all infants die immediately with multiple fractures.