Genetic Bone Disorders Flashcards
What is the other name for osteogenesis imperfecta
brittle bone disease
What is brittle bone disease
a defect in maturation and organisation of type 1 collagen
What type of inheritance are most cases of osteogenesis imperfecta
autosomal dominant
What are the clinical features or autosomal dominant O I
fragility fractures in childhood
short stature
blue sclerae
Loss of hearing
What happens in the rarer autosomal recessive form of OI
usually fatal or results in spinal deformity
What is skeletal dysplasia
Medical term for short stature
What is the most common type or skeletal dysplasia
Achondroplasia
What is the clinical features of achondroplasia
Disproportionately short limbs with prominent forehead and widened nose
Lax joints
normal mental development
What are the bones like in osteogenesis imperfecta
thin (gracile)
thin cortices and osteopenic
What is marfan’s syndrome?
Autosomal dominant or sporadic mutation of the fibrillin gene resulting in tall stature with disproportionately long limbs and ligamentous laxity
What are the associated features of marfans
high arched palate scoiliosis pectus excavatum eye problems eg retinal detachment aortic aneurysn cardiac valve incompetence
What is Ehlers Danlos syndrome?
Heterogeneous condition which is often autosomal dominat and results in elastin and collagen formation which Is abnormal
What are the clinical features of ehlers danlos
hypermobility vascular fragility easy bruising joint instability scoliosis
What is duchenne muscular dystrophy
A defect in dystrophin gene involved in calcium transport results in muscle weakness
What is the clinical sign seen in DMD
Gower’s sign
