Conditions

Osteogenesis Imperfecta

Condition FAQs

Overview

Xray of the lower extremity of a patient with OI who has undergone surgery with telescoping rods.

Osteogenesis Imperfecta (OI) is a rare genetic disorder that causes fragile bones. Osteogenesis Imperfecta means “imperfectly formed bone.” OI is very different from child to child, depending on the severity of the disease in that particular child. Children with a mild form of OI may live for many years with very few fractures (breaks in the bone). Those with severe OI may have hundreds of fractures in their bones.

Cause

Collagen is major part of connective tissue in your body. Type I Collagen helps to make ligaments, bones, skin, and teeth. Children who have OI have a problem in one of their genes that makes Type I Collagen. Their bodies may not be able to make enough collagen, or the collagen that is made is not good quality. This leads to fragile bones that break very easily. However, these bones still heal at a normal rate. Bones that fracture many times may end up being bowed and crooked.

OI is often inherited through a defective gene from one of the parents. However, a child may have a very different form of OI than the parent. There are cases where neither parent has OI, and the child’s gene has spontaneously changed and now does not work properly.

Symptoms

In addition to the abnormal bones, patients with OI may also have blue sclera (the part of the eye that is usually white), crooked bones, scoliosis (curved spine), hearing loss, short height, breathing problems, and bad teeth. Again, symptoms are varied, depending on the type of OI.

There are 4 main types of OI:

Type I – This is the most common form of OI and the mildest type. There is very little bone deformity, but the bones are still easily fractured. The sclera of the eyes have a blue, purple, or gray tint. Hearing loss occurs early. Teeth may get cavities easily or crack.

Type II – This is the most severe form of OI, and many babies often do not survive. Bones may fracture even when the baby is in the womb.

Type III – Babies with this type of OI are often born with fractures, and their bones are very easily broken. The bones become bowed and deformed from multiple fractures. The sclera of the eyes may be white or have a blue, purple, or gray tint. Children are shorter than average, and they may have scoliosis (curved spine), breathing problems, and bad teeth.

Type IV – This OI is moderately severe, between Type I and Type III. Bone deformities are mild to average. Children may have blue sclera that gets whiter when they get older. They may also have bad teeth.

Examination

Bones that break with very little force are the first sign that will lead your doctor to suspect OI. He or she will ask about family’s medical history as well as your child’s medical history and history of broken bones. Your doctor will carefully examine your child’s skin, bone alignment, hair, teeth, and eyes.

Other Tests

X-rays are used to diagnose fractures as well as look at the crookedness of the bones.

Blood tests or skin tests may be needed to make the diagnosis. These tests are used to look for the genes that are defective in OI.

Ultrasound during pregnancy may detect severe OI.

Treatment

There is no cure for OI. However, there are treatments can help with the strength of the bone and can help when your child has a fracture.

Medication – though it is still experimental, sometimes medicine called bisphosphonates can be used to make the bone stronger and less likely to have fractures. They also help with bone pain. They can be given by mouth or through an IV that delivers the medicine into the blood.

Casts/splints – casts and splints are used to hold a broken bone in place while it heals.

Orthoses – lightweight plastic and metal braces can be used on the legs to help patients with severe OI to walk.

Exercise – low impact, weight bearing exercises can help to strengthen the bone, especially after a fracture. The body’s motto is “use it or lose it”– the more you use the bones and muscles for exercise or walking, the stronger the bones and muscles become.

Surgery – your doctor may recommend surgery if a bone breaks several times in the same place or the bone does not heal in a straight position after a fracture. Most of the time, the bones are fixed with straight rods that go down the middle of the bone (like a stick placed in the middle of a straw). Some rods will grow with your child, while others may need to be replaced as your child grows.

Children with severe curvature of the spine (scoliosis) may also need surgery to help straighten the back. Scoliosis bracing does not work well in patients with OI because the ribs are too fragile for the pressure of the brace.

Outcomes

For many children with OI, the number of bone fractures tends to diminish later in life. Adults should avoid medications that decrease bone density, such as steroids, if possible. Smoking and drinking may also lower bone density. Fractures may become more frequent again after menopause in women and beyond age 60 in men.

Femur xray with a healing break around a telescoping rod.

References

Q. How do I care for my child with OI?

Below are some tips from the Osteogenesis Imperfecta Foundation for taking care of children with osteogenesis imperfecta (OI). Do not feel guilty if your child breaks a bone. Children grow and develop, and fractures will occur no matter how careful you are.

Do not be afraid to touch or hold an infant with osteogenesis imperfecta, but be careful. To lift an infant with OI, spread your fingers apart and put one hand between the legs and under the buttocks, and place the other hand behind the shoulders, neck, and head.
Never lift a child with OI by holding him or her under the armpits.
Do not pull on arms or legs or lift the legs by the ankles to change a diaper (particularly for children with severe OI).
Select an infant car seat that reclines. It should be easy to place or remove your child in the seat. Consider padding the seat with foam and using a layer of foam between your child and the harness.
Be sure your stroller is large enough to accommodate casts. Do not use a sling- or umbrella-type stroller.
Follow your doctor's instructions carefully, especially about cast care and mobility exercises. Swimming and walking are often recommended as safe exercises.
Many families with an OI child are worried about being accused of child abuse because of the many fractures that an OI child can have. Always have a letter from your family doctor and a copy of your child's medical records handy.
Children with OI have normal brains and mental capacity. Many OI children do very well at school and grow up to have careers and families.

Children with OI need care from by a team of healthcare professionals, including several types of doctors, a physical therapist, a nurse-clinician, and a social worker. Support from a social worker or psychologist is very helpful for both the child and the family, and often becomes even more important during the teenage years.

Q. Will my child be able to walk?

Mobility for a child with OI depends on how severe the OI is in that patient. Weightbearing activities and maximizing mobility is very important. Some children with OI can walk independently. Others may need help with canes or walker. Others may require wheelchairs, especially for long distances.

Q. Will my child be able to play sports?

Like any children, children with OI benefit from a regular program of physical activity. However, high impact activities such as jumping, diving, gymnastics, and contact sports should be avoided.

Q. If I have another child, will they also have OI?

If a parent has OI, there is a 50% chance that their child will also have OI. The type of OI that the child has, may be more or less severe than what the parent has. If the parents do not have OI, but a child has OI, there is no greater risk than the general population of having a 2^nd child with OI.