Osteogeneisis Imperfecta
- Also called ‘Brittle Bone Disease’
- This is a generalised, predominantly collagen-tissue disorder
- Leads to abnormal bone matrix and reduced bone strength causing bone fragility, fracture risk,
- bone deformity and linear growth deficiency
CLASSIFICATION
- Five major types (1 to 5)
- Autosomal dominant and recessive mutations noted
Clinical findings
- Always differentiate it from Non-Accidental Injury
Skeletal deformities
- Short stature
- Scoliosis/ Kyphosis
- Chest wall deformities(pectus excavatum/ carinatum)
Eye manifestation
- Blue sclerae
Lung problems
- Vulnerable to lung problems asthma and pneumonia.
Cardiac problems
- Increased risk of cardiac valvular disease
- Commonest is called mitral valve prolapse.
Neurological problems
- Macrocephaly.
- Hydrocephalus
- Basilar invagination
Abnormal blood coagulation
- Increased vascular fragility
- Reduced clotting factors
- Abnormal platelet function
Periodontitis
- Periodontitis
- Dentinogenesis imperfecta
Hearing
- Progressive hearing loss in young adulthood
Vision
- The connective tissue problem in OI can extend to the eyes
Diagnosis
Possible to diagnose solely on clinical features.
Biochemical (collagen) or molecular (DNA) tests can help confirm a diagnosis
Radiological features
- Multiple fractures of various ages
- Diaphyseal and vertebral fractures
- Rib fractures
- Callus formation.
- Osteopenia
- Bowed long bones
- Thin and under-tubularized long bones
- Vertebral compression
- Narrow thoracic apex
Low Bone density measurement
Histomorphometry (measurement of shape and form of bone).
Bloods-Calcium, phosphate, Low Serum 25-hydroxyvitamin D
Ultrasound
- The main prenatal screening method
TREATMENT
- No cure for OI.
- Treatment depends on severity of the disease and the age of the patient.
- Multidisciplinary team
- Orthopedic, endocrinologist, pulmonologist, neurologist, surgeon, radiologist and nutritionist etc.
- Medical management includes drug therapy; orthopaedic treatment for fractures and deformity stabilisation; rehabilitation for muscular strengthening and walking strategy
- Directed towards preventing or controlling the symptoms, maximizing independent mobility, and developing optimal bone mass and muscle strength
Medication
- Bisphosphonates
- They slow the loss of existing bone.
- Reduce vertebral compressions and some long bone fractures
- Prior to starting a bisphosphonate, maximise calcium and vitamin D supplementation, as sufficient concentrations are necessary for an optimal treatment response
Follow up
- Hearing tests and MRI of the hearing canals
- Eyes exams are recommended every 2 to 3 years