Osteogenesis Imperfecta (Brittle Bone Disease)

Osteogenesis imperfecta (OI) is a connective tissue disease. It makes your bones fragile. You might break a bone with little or no force. That’s why OI is also known as brittle bone disease. It makes your bones weaker and thinner than they should be.

Osteogenesis imperfecta also affects your body’s ability to make collagen properly. Collagen is a protein. It helps develop your:

• Bones
• Skin
• Muscles
• Tendons

Osteogenesis imperfecta can cause many broken bones throughout your life. It can also affect your:

• Teeth
• Skin
• Spine
• Lungs
• Other internal organs

The most common form of osteogenesis imperfecta usually causes mild symptoms. But OI can also cause severe disabilities and be fatal.

Types of osteogenesis imperfecta

Healthcare providers classify osteogenesis imperfecta into 19 types. Types I through IV are the most common.

People with type I have lower amounts of normal collagen than they should. People with types II, III and IV have improperly formed collagen. These types cause more severe symptoms.

Type 1

This is the most common form of OI. It causes milder symptoms than other types. You’ll break bones more easily than usual. But most broken bones happen before puberty. It doesn’t cause bone deformity.

Type II

Type II is the most serious form. Babies with type II die at or shortly after birth. It causes fatal complications like:

• Underdeveloped lungs
• Serious bone deformities
• Multiple broken bones before birth

Type III

Type III is the second most severe form. It causes dangerous bone deformities. This makes your bones very fragile. You’ll live with physical disabilities. Babies with type III are often born with broken bones.

Type IV

Type IV is more severe than type I. But it’s less severe than type III. Your bones will be more fragile than usual. But they won’t break as often as with type III.

Symptoms of osteogenesis imperfecta

Signs and symptoms of this condition can include bone issues like:

• Weak bones that break easily
• Bone deformities
• Bone pain
• The white part of your eye looking blue or gray
• Barrel-shaped rib cage
• Curved spine (kyphosis or scoliosis)
• Small stature
• Triangular face shape
• Weak, brittle or discolored teeth
• Teeth that don’t align properly

You might also experience:

• Bruising easily
• Difficulty breathing
• Hearing loss
• Loose joints
• Muscle weakness

Osteogenesis imperfecta causes

A genetic change causes this condition. Changes in the COL1A1 or COL1A2 genes cause most cases. Changes in other collagen genes cause rarer types of OI.

The genetic changes that cause OI can be random. You may also inherit them from your biological parents. You’re more likely to have OI if someone else in your biological family has it. Some people have the genetic variation but never develop osteogenesis imperfecta.

You can inherit the gene change from one parent (dominant) or both (recessive), depending on the type of OI.

Complications of brittle bone disease

Complications of osteogenesis imperfecta can include:

• Heart disease, including heart failure
• Frequent pneumonia
• Respiratory issues, including respiratory failure
• Nervous system issues

How doctors diagnose osteogenesis imperfecta

Healthcare providers usually diagnose brittle bone disease in childhood with:

• Genetic testing
• Bone density tests

A pregnancy care provider might suspect osteogenesis imperfecta before birth. They may see signs of OI on ultrasound images. They can confirm the diagnosis during pregnancy with an amniocentesis. They can also diagnose it after the baby is born.

Ask your provider about genetic counseling. This can help you understand your risk of passing osteogenesis imperfecta to your biological children.

How is osteogenesis imperfecta treated?

Treatment for osteogenesis imperfecta can increase your bone strength. It can also help you live more independently. You might need:

• Occupational therapy: Helps with everyday tasks
• Physical therapy: Builds strength in bones and muscles
• Assistive devices: Walkers, canes or crutches can improve mobility
• Oral and dental care: Regular dental checkups and/or orthodontic care for tooth and jaw issues
• Pulmonary care: Manages breathing issues
• Medications: Bisphosphonates to strengthen bones
• Surgery: Metal rods support curved or fragile bones
• Braces, splints or casts: Stabilize bones after breaks or surgery

When should I see my healthcare provider?

Talk to a healthcare provider if you think you or your child has symptoms of OI. Tell your provider if you break bones easily. Especially without a major injury. Your provider can recommend additional testing if needed.

Go to the emergency room if you or your child breaks a bone. Tell providers in the ER if you know you have osteogenesis imperfecta.

What is the life expectancy of a person with osteogenesis imperfecta?

Mild forms of osteogenesis imperfecta usually won’t affect your lifespan. But life expectancy varies depending on the type.

Can osteogenesis imperfecta be prevented?

Because brittle bone disease is a genetic condition, you can’t prevent it. If you or your partner has OI or if you have a relative with the condition, you can talk to a genetic counselor. They can advise you about the risks of passing on the condition.