What are the other Names for this Condition? (Also known as/Synonyms)

• Fragilitas Ossium
• Glass-Bone Disease
• Vrolik Syndrome

What is Osteogenesis Imperfecta? (Definition/Background Information)

• Osteogenesis Imperfecta (OI) is a genetic disorder that is characterized primarily by the presence of fragile bones, along with a host of other symptoms that includes hearing loss, weak muscles, brittle teeth, etc.
• There are 8 types of OI, and a majority of them are genetically termed as ‘autosomal dominant’ type (meaning that if the abnormal gene is present in any one parent, then the disorder is inherited)
• However, some types are ‘autosomal recessive’ (the abnormal genes have to be present in both the parents for the condition to develop) and the rest ‘de novo’ (those occurring due to individual, spontaneous mutations)
• The treatment and prognosis depend on the type of Osteogenesis Imperfecta, an individual is affected with

Who gets Osteogenesis Imperfecta? (Age and Sex Distribution)

• Osteogenesis Imperfecta is uniformly distributed among both genders, all races and ethnic groups
• Any individual may develop OI unexpectedly, irrespective of the fact that there is no family medical history of the illness
• An individual with OI has a greater chance of handing down the disorder (and the gene) to their offspring. This is also dependent upon the type of OI the individual is affected with

What are the Risk Factors of Osteogenesis Imperfecta? (Predisposing Factors)

Genetic factors play a major role in Osteogenesis Imperfecta; those with a family history of the condition are at a great risk.

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Osteogenesis Imperfecta? (Etiology)

• An error in gene mutation leading to deficient body production of collagen (a naturally-occurring protein found in tissues, ligaments, cartilages, and bones) causes Osteogenesis Imperfecta. Mild OI type may cause a few difficulties, but individuals affected by more serious OI types, can experience a lifetime of fractures
• Collagen (type 1 collagen) is a major building block of all bones and tissues, giving them strength and flexibility. In OI, both the quality and quantity of collagen production, are affected by improper gene functioning
• These genes may be inherited from the parents, in an autosomal dominant or autosomal recessive manner. Sometimes, the gene abnormalities leading to improper functioning occur spontaneously, in the prenatal stage, causing OI

What are the Signs and Symptoms of Osteogenesis Imperfecta?

The distinctive sign of all forms of Osteogenesis Imperfecta is brittle bones, due to a lack of sufficient quality collagen. Other symptoms depend on the severity of the disorder, which range from mild (type 1 OI), to moderate (type 4 OI, 5 OI, 6 OI), to severe (type 2 OI, 3 OI, 7 OI, 8 OI) types.

In general, a few of the signs and symptoms are:

• Loose joints, weak muscles
• Low density, deformed bones
• Curved spine, odd-shaped ribcage
• Short stature, small body, permanent deformities
• Brittle teeth (due to improper formation of dentin)
• Sclera (eye white) has a pale blue, grey, purple coloration (seen in types 1 OI and 3 OI)
• Hearing loss in young adults (types 1 OI, 3 OI, 4 OI, and 6 OI)
• Respiratory problems, due to poor lung development (types 2 OI and 3 OI)
• Serious heart conditions (type 2 OI)
• Fish-scale appearance (type 6 OI)
• Mesh-like bones (type 5 OI)

How is Osteogenesis Imperfecta Diagnosed?

A physician conducts a medical history and physical examination of the individual that includes information related to family history of Osteogenesis Imperfecta and personal medical history. Children, who suffer fractures and broken bones regularly, are suspected of having OI. A few diagnostic tests performed include:

• A skin punch biopsy (skin sample is removed) to test one’s collagen or DNA, is a conclusive test for OI
• Blood test
• X-ray evaluation of the bones
• Ultrasound scan (can be used to diagnose OI in fetus)
• Placenta study (chorionic villus sampling, during pregnancy), to determine if the baby suffers from OI

Note:

• Diagnostic studies on pregnant women are conducted, only if there is a family history of Osteogenesis Imperfecta
• Genetic testing cannot establish some forms of the disorder
• A negative result on collagen analysis, does not indicate the absence of OI; other DNA tests may be required to arrive at a definitive diagnosis

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Osteogenesis Imperfecta?

Complications that develop due to Osteogenesis Imperfecta vary, and are characteristic of the type and severity of the disorder. They also depend on the kind of specific defects and deformities that are observed. The complications could include:

• Invariably, all individuals suffer from a fragile skeletal system and brittle bones, resulting in many fractures during their lifespan
• Other major complications are hearing loss, heart and lung disorders, brain stem and spinal cord defects, permanently deformed bones, etc.
• Growth from childhood to adult, and the hormonal changes involved, may adversely affect the course of OI symptoms
• It is difficult to obtain cooperation for physical therapy treatment from young children, as they are afraid to move, fearing pain
• Those with severe forms of OI have to live with a constant pressure of handling their daily life. This can cause deep emotional and psychological distress in them

How is Osteogenesis Imperfecta Treated?

Osteogenesis Imperfecta cannot be cured; proper care with symptomatic treatment (with surgical intervention as necessary) and a healthy lifestyle can help manage the disorder to a certain degree. Nevertheless, all these are contingent upon the type of OI disorder (type 1 to type 8) the individual is affected with.

The treatment measures include:

• Reduced pain and fracture rates have been achieved using biophosphonate drugs. These are helpful in treating osteoporosis, and in increasing bone strength and density
• Use of growth hormones, certain new medications to treat bone brittleness and low-density bones. However, these are still in the early phases of testing (with ongoing clinical trials)
• Calcium and vitamin D rich diet, use of vitamin supplements
• Physiotherapy, low impact exercising (like swimming, using light weights) to strengthen muscles, improve movement, have proven to be beneficial
• Children, young adults, and their parents, are trained on techniques for safe movement, proper positioning, energy conservation, and on how to be careful, while performing regular physical activities
• Wheelchairs, splints, crutches, braces are used to provide physical support and promote mobility
• Surgically-inserted metal rods (rodding) are useful in preventing fractures and improve bone strength
• Deformed bones (spinal curve, bowed legs) may be corrected using reconstructive surgery
• Antibiotics and antiseptics are used to treat bone infections

How can Osteogenesis Imperfecta be Prevented?

• Currently, there are no specific methods or guidelines to prevent Osteogenesis Imperfecta genetic condition
• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders
• Those with OI would benefit from a healthy lifestyle that includes a good nutritious diet, light exercising, activities that promote bone strength, avoidance of tobacco and excessive alcohol, caffeine, etc.

What is the Prognosis of Osteogenesis Imperfecta? (Outcomes/Resolutions)

The prognosis is dependent upon the type of Osteogenesis Imperfecta an individual is affected with and the severity of the symptoms:

• Those with type 1 OI (most common and mild) can more or less, lead a normal life
• Infants with type 2 OI, die within a year of their birth, due to heart and lung problems
• There is a reduced life expectancy with the severe forms of OI; individuals may have serious bone deformities and suffer many fractures lifelong
• Individuals with moderate forms of OI may have a near normal life expectancy, but often require physical aids to walk and to lead a normal life
• Medical experts are vigorously exploring various treatment options and medications to assist the disorder-affected

However, regardless of the trials and difficulties of Osteogenesis Imperfecta; with constant care, medical support, a good diet and healthy lifestyle, individuals are able to attend schools and colleges, take part in sports and such activities, have a career, raise families, and lead a productive life.

Additional and Relevant Useful Information for Osteogenesis Imperfecta:

There are voluntary organizations and support groups that provide help, encouragement and understanding to the people affected by Osteogenesis Imperfecta.