|
|
|
|
|
Osteogenesis
Imperfecta
Information
provided by Osteogenesis Imperfecta Foundation
GENERAL INFORMATION ABOUT OSTEOGENESIS IMPERFECTA
The term osteogenesis imperfecta literally means "bone that is
imperfectly made from the beginning of life." OI is a
genetic disorder. Osteogenesis imperfecta (OI) is the result of a
mutation in one of the two genes that carry instructions for making
type 1 collagen (the major protein in bone and skin). The mutation may
result in either a change in the structure of type 1 collagen
molecules or in the number of collagen molecules made. Either of
these changes results in weak bones that fracture easily.
The mutation is found on the COL1A2 gene on the long arm of chromosome
7 and/or the COL1A1 gene on the long arm of chromosome 17.
In recent years, researchers have studied skin cells, the collagen
molecules they make, and the genes themselves from individuals with
different forms of OI. Results of these studies show that the vast
majority of people with OI, even those who are the only affected
people in a family, have dominantly inherited forms of the disorder.
There are roughly 4 types of OI ranging from mild to very severe. OI
is a highly variable condition. The types differ from each other and
there is variation within the types as well. OI occurs about
once in every 10,000 births and the incidence is about the same
world wide. Other consequences of the disorder can include defective
teeth (dentinogenesis) hearing loss, early osteoporosis, short
stature, spine problems such as scoliosis and respiratory problems.
Treatments usually are directed at the symptoms i.e. setting broken
bones, prevention of new fractures or strengthening of the weak bones.
Exercise and physical therapy can help the person affected by OI
develop muscle strength and prevent bone loss. Braces can provide
external support and surgically implanted rods can provide internal
support. Current research is looking at the effectiveness of growth
hormone therapy, gene therapy, the use of drugs (bisphosphonates) and
bone marrow transplants.
For more detailed information please visit the web site at www.oif.org
and link to the section "Information about OI."
INFORMATION FOR ADULTS
Many of the doctors on our medical advisory council are concerned
about the risk of osteoporosis as a factor in managing osteogenesis
imperfecta during the adult years. They think this additional bone
loss may account for the pain, fatigue and fracture cycles many adults
experience as they get older. Adults with OI are at risk for
osteoporosis because of an inactive life style, being over weight,
family tendency, immobilization due to fractures and the affects of
time on bones already weak from osteogenesis imperfecta.
To help you stay in good health, and maintain mobility, you will want
to follow the guidelines for the prevention of osteoporosis which
include exercise as possible, maintaining a healthy weight, not
smoking, not using drugs that contain steroids, and in some cases
treatment with medications to stop bone loss. We are told that many
adults who have OI are being treated with drugs from the bisphosphonate
family such as Fosamax and Aredia. For the majority of
people, we are told, this treatment is successful at
reducing the rate of bone loss. In some people, an increase in bone
density has been reported. Bisphosphonates are approved by the FDA as
treatment for osteoporosis and some other bone disorders, but are
still considered experimental as a treatment for OI. A lot of research
is being done at this time into the most effective use of these drugs.
Depending on your overall physical condition, walking, bike riding
and/or swimming can be good exercises. Some people benefit from the
aquatics programs designed for those with arthritis. Be sure to talk
to your doctor and/or physical therapist before beginning any
exercise program.
Since osteogenesis imperfecta is a collagen disorder, more than your
bones are affected. Old injuries to feet, ankles or knees may flare up
due to loose ligaments. Fallen arches are a common problem. Exercises
and orthotics can often provide relief. If you have a history of spine
fractures, or scoliosis, your respiratory function should be checked
as part of your routine physicals. Individuals with OI may also
develop various cardiovascular problems.
Adults who have OI face the same risk factors as other American adults
for developing cancer, diabetes and other health problems.
Back Page
|
|
|
|
