Wayne A. Cabral, Ph. Osteogenesis imperfecta OI is a rare genetic disorder affecting the protein collagen, which is found in bone, teeth, skin, and tendons. People with the disorder have bones that can break easily, often from a mild impact or for no apparent cause. The disorder may also result from changes in genes that determine the shape and configuration of the collagen molecule. Depending on the gene involved, the disorder can range from mild to severe, and may even be fatal.
In mild forms, bones may break only a few times in a person's life. People with this form of OI may be somewhat shorter than others in their family, have frequent fractures that decrease after puberty, and have mild to moderate bone deformity. Identifying features include hypertrophic calluses that may form at fracture or surgical procedure sites and restricted forearm rotation due to calcification to the membrane between the radius and ulna. This is an extremely rare form.
It is distinguished by a characteristic mineralization defect that can be seen in biopsied bone. Prenatal Diagnosis Prenatal testing can detect all forms of OI if the genetic alterations are known. Postnatal Diagnosis The diagnostic process begins with a clinical evaluation. Differential Diagnosis A variety of disorders may present with recurrent fractures due to bone fragility- that is, not everyone with fractures has OI.
Child Abuse The question of non-accidental injury versus osteogenesis imperfecta arises most often when infants and toddlers experience unexpected or unexplained broken bones.
Medical Team Medical care for both children and adults who have OI involves an interdisciplinary team. Fracture Care: casting, splinting, and bracing broken bones can help them heal properly. However, long periods of immobility can further weaken bones and lead to muscle loss, weakness, and more fractures.
Many orthopedists prefer to treat fractures with short-term immobilization in lightweight casts, splints, or braces to allow some movement as soon as possible after the fracture.
Physical Therapy and Saf e Exercise: Goals for physical therapy include expanding and maintaining functioning and promoting independence. A typical program includes muscle strengthening and aerobic conditioning. Physical therapy often begins in infancy to counteract the delay in motor skill development many children experience due to OI related muscle weakness.
Adaptive devices may be needed. Occupational therapy can help with fine motor skills and selection of adaptive equipment for daily living.
As a child with OI grows older and gains more independence, he or she will benefit from continued physical activity. Adults with OI also benefit from safe and regular exercise to maintain bone and muscle mass. Swimming and water therapy are particularly well-suited for people with OI of all ages, as they allow independent movement with little fracture risk.
Walking is also excellent exercise for those who are able with or without mobility aids. Surgery : Surgery may be needed to repair a broken bone, correct bone deformities such as bowing, stabilize the spine, or repair tiny bones in the middle ear and improve hearing. Many children with OI undergo a surgical procedure known as rodding- in which metal rods are inserted into the long bones to control fractures and improve deformities that interfere with function.
Both non-expandable and expandable rods are available. Medications: Bisphosphonate drugs, which are currently approved by the Food and Drug Administration FDA to prevent and treat osteoporosis are used off label to increase bone density in children and adults with moderate and severe OI.
Other drugs that were developed to treat osteoporosis are also used to prevent age-related bone loss in adults who have OI. Teriparatide a drug based on the parathyroid hormone is one of them. Treatments under study include growth hormone and gene therapies. The search continues for a drug treatment that is specific to OI.
Healthy Lifestyle: People with OI benefit from a healthy lifestyle that includes safe exercise and a nutritious diet. Adequate intake of nutrients, such as Vitamin D and calcium, are necessary to maintain bone health. However, extra-large doses of these nutrients are not recommended. Maintaining a healthy weight is important since extra weight adds stress to the skeleton, heart, and lungs and reduces the ability to move easily. In addition, people with OI should avoid smoking, second hand smoke, excessive alcohol or caffeine consumption, and steroid medications, all of which reduce bone density.
Other treatments that focus on OI-related symptoms include: hearing aids, crowns for brittle teeth, supplemental oxygen for people with breathing problems, and mobility aids. References Sutton VR. Differential Diagnosis of Osteogenesis Imperfecta in Children In Shapiro JR.
Bober MB Ed. Website- Information about and resources for genetic testing may be found on GeneTests www. Supporting Documents Height and weight charts for the child with OI Types III and IV Research article: Longitudinal growth curves for children with classical osteogenesis imperfecta types III and IV caused by structural pathogenic variants in type I collagen Research article: Cross-sectional and longitudinal growth patterns in osteogenesis imperfecta: implications for clinical care.
Non-Skeletal Issues in OI. Dental Oral-Facial : OI affects the growth of both jaws and tooth development. Regular dental care is recommended for all people with OI beginning within 6 months after the primary teeth erupt and continuing throughout life.
Other common oral cavity problems related to OI include: impacted teeth, anterior and posterior open and cross bites and skeletal class III malocclusion. Although respiratory problems are usually more severe in those with severe OI, the primary collagen defect affects lung tissue in all people with OI, including those with a mild phenotype. Altered lung tissue predisposes the person to respiratory infections.
Rates of asthma and pneumonia are higher in children and adults who have OI. Chest wall deformities, rib fractures, kyphoscoliosis, chest wall weakness, limited mobility, and the effects of gastrointestinal problems such as constipation and reflux all contribute to poor pulmonary function. Fatigue, breathlessness, and wheezing are frequent symptoms.
Manifestations can also include exercise intolerance and sleep apnea. Bone quality and structural abnormalities of the ear bones-including visible deformities in the ossicles and the inner ear- contribute to the loss. Environmental factors affecting hearing may cause a loss sooner than the unaffected population.
Most hearing loss in OI is mixed but conductive, and sensorineural types of loss are seen. There is a range of severity, and some people report experiencing tinnitus and vertigo. Physicians should be alert to dangers of ototoxins in this population.
The most frequently reported cardiovascular issues are hypertension and mitral valve prolapse. Heart valve problems are believed to develop over time. They are more of a concern for adults with OI, but are infrequently seen in children.
Cardiac surgery, including valve replacement, has been successful. Neurological: Intelligence is typically normal in people with OI. People with all subtypes of OI may develop basilar impression BI over time, with those with severe OI having greater risk. Enlarged head circumference is seen in infants and children with OI and may or may not be caused by hydrocephalus. Evaluation is required; shunting is possible Vision: People with OI seem to experience the common refractive errors such as myopia, hyperopia, or astigmatism at about the same rate as people without OI.
Story Source: Materials provided by University of Zurich. Makareeva, Andreas R. Marini, Vorasuk Shotelersuk. MBTPS2 mutations cause defective regulated intramembrane proteolysis in X-linked osteogenesis imperfecta. Nature Communications , ; 7: DOI: ScienceDaily, 6 July University of Zurich. New type of rare brittle-bone disease discovered. Retrieved November 13, from www.
His or her position should be changed throughout the day. As your baby gets older, it will be important to help him or her avoid injuries. A physical or occupational therapist, as well as other healthcare providers, can help. Avoiding infection. Your baby may be more likely to get colds and other respiratory infections. And he or she may get sicker with an infection.
Make sure your baby has all of his vaccines immunizations. During cold and flu season, stay away from crowds. Make sure that you wash your hands well. As your child gets older, teach him or her to do the same. Dealing with pain. Fractures and deformities can be very painful. Talk with your baby's healthcare provider about pain medicine or other ways to lessen pain. Dealing with challenges. As your child gets older, he or she may have emotional and physical challenges.
Regular medical and dental checkups. Your baby will need regular checkups and tests. These include eye and dental exams. Weight management. When your child gets older he or she may gain weight because of the decreased physical activity. Has changes in his or her behavior that may mean an injury or other problem. For example, your baby may be fussy or irritable. Health Home Conditions and Diseases. What is osteogenesis imperfecta in children?
The OI types are as follows: Type I. There are few fractures and deformities Type II. It is common to have enlarged thickened areas hypertrophic calluses in the areas where large bones are fractured Type VI. Very rare. Symptoms are medium.
What causes osteogenesis imperfecta in a child? What are the symptoms of osteogenesis imperfecta in a child? The symptoms of OI vary greatly within and between types. Symptoms of OI include: Easily broken bones Bone deformities, such as bowing of the legs Discoloration of the white of the eye sclera , may be blue or gray in color A barrel-shaped chest A curved spine A triangle-shaped face Loose joints Muscle weakness Skin that easily bruises Hearing loss in early adulthood Soft, discolored teeth The symptoms of osteogenesis imperfecta may look like other medical conditions.
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