Osteogenesis Imperfecta is a relatively rare disorder. Diagnosing Osteogenesis Imperfecta is primarily a clinical process. It is often difficult or inconclusive without a physician familiar with the disorder. Diagnosis of Osteogenesis Imperfecta is based on the discovery of a number of fractures in the infant's or child's arms, ribs, and legs. X-rays can uncover fractures that might not be obvious.

A doctor can often make the diagnosis of OI after a thorough physical examination, as well as a review of a family's medical history. However, sometimes it is necessary to perform laboratory tests in order to confirm the disease. These tests will either be biochemical to test the collagen or molecular to examine the genetic pattern of the disease. The results of the lab test often take several weeks.

Child abuse can also produce broken bones, but the ways the bones break and which bones are typically broken is usually different than in Osteogenesis Imperfecta. Some children with milder forms of OI might not be diagnosed until they are older. Specific genetic testing is available for some forms of OI.

Ultrasound can often detect severe cases of Osteogenesis Imperfecta during pregnancy. Prenatal diagnosis in second trimester by ultrasound in the most severe forms. Routine scanning shows shortness and deformity of limbs and abnormal skull shape. There is also absence of mineralization and deformity of ribs causing 'champagne cork' appearance on AP projection.

Genetic testing may be able to identify the mutation, particularly if the parent's mutation is also known. But in many cases, bone fractures that occur with little or no trauma are often the first indication that a person has Osteogenesis Imperfecta.

In people with Osteogenesis Imperfecta, one of the genes that tells the body how to make a specific protein is defective. This protein (type I collagen) is a major component of the connective tissues in bones. Type I collagen is also important in forming ligaments, teeth, and the white outer tissue of the eyeballs (Sclera).

As a result of the defective gene, not enough type I collagen is produced, or the collagen that is produced is of poor quality. In either case, the result is fragile bones that break easily but can heal at a normal rate.

Multiple broken bones are common. Other features include deafness, white of the eyes appear bluish, tooth abnormalities, chest deformities and short stature. There is no specific treatment. Genetic counselling is important for families with the disease.