Osteogenesis imperfecta (OI) literally means "imperfectly formed bone." People with osteogenesis imperfecta have an error (mutation) in the genetic instructions on how to make strong bones. This may cause the bones to break easily.
Causes
Osteogenesis imperfecta is relatively rare. In some cases, the parent has osteogenesis imperfecta and the condition has been genetically transmitted to the child. But, the child's symptoms and the degree of disability could be very different from that of the parent. In some children, neither parent has osteogenesis imperfecta. In these cases, the genetic defect is a spontaneous mutation.
Diagnosis/Symptoms
Osteogenesis imperfecta is a relatively rare disorder. Ultrasound can often detect severe cases of osteogenesis imperfecta during pregnancy. 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.
There are four recognized types of osteogenesis imperfecta, which vary in severity and characteristics. Several other findings are also associated with osteogenesis imperfecta, including short stature, a triangular face, respiratory problems, and hearing loss. Each person with osteogenesis imperfecta may have a different combination of clinical characteristics.
Type I Osteogenesis Imperfecta
Type I osteogenesis imperfecta is the most common and mildest type of this disease. While the structure of the collagen is normal, there is less collagen than there should be. There is little or no bone deformity, although the bones are fragile and easily broken. The effects of osteogenesis imperfecta may extend to the teeth, making them prone to cavities and cracking. The whites of the eyes may have a blue, purple, or gray tint.
Type II Osteogenesis Imperfecta
Type II osteogenesis imperfecta is the most severe form of the disease. The collagen does not form properly. Bones may break even while the fetus is in the womb. Many infants with type II osteogenesis imperfecta are stillborn or die shortly after birth.
Type III Osteogenesis Imperfecta
Type III osteogenesis imperfecta also has improperly formed collagen and often severe bone deformities plus additional complications. The infant is often born with fractures. The whites of the eyes may be white, blue, purple, or gray. People with type III osteogenesis imperfecta are generally shorter than average. They may have spinal deformities, respiratory complications, and brittle teeth.
Type IV Osteogenesis Imperfecta
Type IV osteogenesis imperfecta is moderately severe, with improperly formed collagen. Bones fracture easily, but the whites of the eyes are normal. Some people with type IV osteogenesis imperfecta may be shorter than average and may have brittle teeth. Bone deformities are mild to moderate.
Treatment
While there is no cure for osteogenesis imperfecta, there are opportunities to improve the child's quality of life. Treatment must be individualized and depends on the severity of the disease and the age of the patient. Care is provided by a team of health-care professionals, including several types of doctors, a physical therapist, a nurse-clinician and a social worker.
Nonsurgical Treatment
In most cases, treatment will be nonsurgical.
Medical bisphosphonates, given to the child either by mouth or intravenously, slow down bone resorption. In children with more-severe osteogenesis imperfecta, bisphosphonate treatment often decreases the number of fractures and bone pain. These medications must be administered by properly trained doctors and require close monitoring.
Casting, bracing, or splinting of fractures is necessary to immobilize the bone so that healing can occur. Movement and weight bearing are encouraged as soon as possible after fractures to increase mobility and decrease the risk of future fractures.
Precautions
Here are some tips developed by the Osteogenesis Imperfecta Foundation for dealing with children with osteogenesis imperfecta.
Don't be afraid to touch or hold an infant with osteogenesis imperfecta, but be careful. Never lift a child with osteogenesis imperfecta 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. To lift an infant with osteogenesis imperfecta, spread your fingers apart and put one hand between the legs and under the buttocks; place the other hand behind the shoulders, neck and head.
Do not feel guilty if a fracture does occur. Children must develop and fractures will occur no matter how careful you are.
Select an infant car seat that reclines. It should be easy to place or remove the child in the seat. Consider padding the seat with foam and using a layer of foam between the child and the harness.
Be sure your stroller is large enough to accommodate casts. Don't use a sling or umbrella-type stroller.
Follow your doctor's instructions carefully, especially with regard to cast care and mobility exercises. Swimming and walking are often recommended as safe exercises.
Avoid activities such as smoking, drinking and taking steroids because they have a negative impact on bone density.
Increasing awareness of child abuse and a lack of awareness about osteogenesis imperfecta may lead to inaccurate conclusions about a family situation. Always have a letter from your family doctor and a copy of your child's medical records handy.
Surgical Treatment
Repeated fractures of the same bone, deformity, or fractures that do not heal properly are all indications that surgery may be necessary. Metal rods may be inserted in the long bones of the arms and legs. Some rods are a fixed length and must be replaced as the child grows. Other rods are designed like telescopes so they can expand along with the bone growth. However, other complications may occur with telescoping rods. Do not hesitate to ask your orthopaedic surgeon about both options.
In many children with osteogenesis imperfecta, the number of times their bones fracture decreases significantly as they mature. However, osteogenesis imperfecta may become active again after menopause in women or after the age of 60 years in men.
Scoliosis, or curvature of the spine, is a problem for many children with osteogenesis imperfecta. Bracing is the usual treatment for scoliosis, but it is often ineffective in children with osteogenesis imperfecta. Spinal fusion, in which the vertebrae are realigned and fused together, may be recommended to prevent excessive curvature.
Causes
Osteogenesis imperfecta is relatively rare. In some cases, the parent has osteogenesis imperfecta and the condition has been genetically transmitted to the child. But, the child's symptoms and the degree of disability could be very different from that of the parent. In some children, neither parent has osteogenesis imperfecta. In these cases, the genetic defect is a spontaneous mutation.
Diagnosis/Symptoms
Osteogenesis imperfecta is a relatively rare disorder. Ultrasound can often detect severe cases of osteogenesis imperfecta during pregnancy. 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.
There are four recognized types of osteogenesis imperfecta, which vary in severity and characteristics. Several other findings are also associated with osteogenesis imperfecta, including short stature, a triangular face, respiratory problems, and hearing loss. Each person with osteogenesis imperfecta may have a different combination of clinical characteristics.
Type I Osteogenesis Imperfecta
Type I osteogenesis imperfecta is the most common and mildest type of this disease. While the structure of the collagen is normal, there is less collagen than there should be. There is little or no bone deformity, although the bones are fragile and easily broken. The effects of osteogenesis imperfecta may extend to the teeth, making them prone to cavities and cracking. The whites of the eyes may have a blue, purple, or gray tint.
Type II Osteogenesis Imperfecta
Type II osteogenesis imperfecta is the most severe form of the disease. The collagen does not form properly. Bones may break even while the fetus is in the womb. Many infants with type II osteogenesis imperfecta are stillborn or die shortly after birth.
Type III Osteogenesis Imperfecta
Type III osteogenesis imperfecta also has improperly formed collagen and often severe bone deformities plus additional complications. The infant is often born with fractures. The whites of the eyes may be white, blue, purple, or gray. People with type III osteogenesis imperfecta are generally shorter than average. They may have spinal deformities, respiratory complications, and brittle teeth.
Type IV Osteogenesis Imperfecta
Type IV osteogenesis imperfecta is moderately severe, with improperly formed collagen. Bones fracture easily, but the whites of the eyes are normal. Some people with type IV osteogenesis imperfecta may be shorter than average and may have brittle teeth. Bone deformities are mild to moderate.
Treatment
While there is no cure for osteogenesis imperfecta, there are opportunities to improve the child's quality of life. Treatment must be individualized and depends on the severity of the disease and the age of the patient. Care is provided by a team of health-care professionals, including several types of doctors, a physical therapist, a nurse-clinician and a social worker.
Nonsurgical Treatment
In most cases, treatment will be nonsurgical.
Medical bisphosphonates, given to the child either by mouth or intravenously, slow down bone resorption. In children with more-severe osteogenesis imperfecta, bisphosphonate treatment often decreases the number of fractures and bone pain. These medications must be administered by properly trained doctors and require close monitoring.
Casting, bracing, or splinting of fractures is necessary to immobilize the bone so that healing can occur. Movement and weight bearing are encouraged as soon as possible after fractures to increase mobility and decrease the risk of future fractures.
Precautions
Here are some tips developed by the Osteogenesis Imperfecta Foundation for dealing with children with osteogenesis imperfecta.
Don't be afraid to touch or hold an infant with osteogenesis imperfecta, but be careful. Never lift a child with osteogenesis imperfecta 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. To lift an infant with osteogenesis imperfecta, spread your fingers apart and put one hand between the legs and under the buttocks; place the other hand behind the shoulders, neck and head.
Do not feel guilty if a fracture does occur. Children must develop and fractures will occur no matter how careful you are.
Select an infant car seat that reclines. It should be easy to place or remove the child in the seat. Consider padding the seat with foam and using a layer of foam between the child and the harness.
Be sure your stroller is large enough to accommodate casts. Don't use a sling or umbrella-type stroller.
Follow your doctor's instructions carefully, especially with regard to cast care and mobility exercises. Swimming and walking are often recommended as safe exercises.
Avoid activities such as smoking, drinking and taking steroids because they have a negative impact on bone density.
Increasing awareness of child abuse and a lack of awareness about osteogenesis imperfecta may lead to inaccurate conclusions about a family situation. Always have a letter from your family doctor and a copy of your child's medical records handy.
Surgical Treatment
Repeated fractures of the same bone, deformity, or fractures that do not heal properly are all indications that surgery may be necessary. Metal rods may be inserted in the long bones of the arms and legs. Some rods are a fixed length and must be replaced as the child grows. Other rods are designed like telescopes so they can expand along with the bone growth. However, other complications may occur with telescoping rods. Do not hesitate to ask your orthopaedic surgeon about both options.
In many children with osteogenesis imperfecta, the number of times their bones fracture decreases significantly as they mature. However, osteogenesis imperfecta may become active again after menopause in women or after the age of 60 years in men.
Scoliosis, or curvature of the spine, is a problem for many children with osteogenesis imperfecta. Bracing is the usual treatment for scoliosis, but it is often ineffective in children with osteogenesis imperfecta. Spinal fusion, in which the vertebrae are realigned and fused together, may be recommended to prevent excessive curvature.
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