Congenital MSK Disorders Flashcards
what is osteogenesis imperfecta
also known as brittle bone disease it is a defect of the maturation and organisation of type 1 collagen (which accounts for most of the organic composition of bone)
what are the symptoms of autosomal dominant cases (majority) of osteogenesis imperfecta
multiple fragility fractures of childhood short stature with multiple deformities blue sclerae with loss of hearing
what are the symptoms of autosomal recessive cases of osteogenesis imperfecta
fatal in perinatal period or associated with spinal deformity
how do the bones tend to be in osteogenesis imperfecta
thin (gracile) with thin cortices and osteopenia
what do different types of osteogenesis imperfecta look like
how is osteogenesis imperfecta diagnosed
thorough but sensitive history and exam beware of child abuse or ostopenia (result from prematurity and result in low energy fractures)
what is treatment of osteogenesis imperfecta
fractures heal with abundant but poor quality callus and treated with splintage, traction or surgical stabilisation
some cases of osteogenesis imperfecta develop progressive deformity, how is this treated
may require multiple osteotomies and intramedullary stabilisation for correction (Sofield procedure)
what is skeletal dysplasia
medical term for short stature which is due to genetic error (hereditary or sporadic)
what is most common type of skeletal dysplasia and what are its features
achondroplasia autosomal dominant but >80% cases sporadic short limbs with prominent forehead and widened nose joints are lax and mental development normal
other types of skeletal dysplasia may be associated with what
learning difficulties spine deformity limb deformity internal organ dysfunction craniofacial abnormalities tumour (esp haemangiomas) joint hyper mobility atlanta-axial subluxation spinal cord compression (myelopathy) intrauterine or premature death
how is skeletal dysplasia treated
genetic testing orthopedic = deformity correction (eg scoliosis) and limb lengthening growth hormone therapy may be appropriate
what are connective tissue disorders associated with
disorders of collagen synthesis (mainly type 1) that affects soft tissues more than just bone
what are examples of connective tissue disorders
generalised (familial) joint laxity marfan’s syndrome ehlers-danlos syndrome downs syndrome
what is generalised familial joint laxity and what is consequence
autosomal dominant hypermobility more prone to soft tissue injuries (ankle sprains) and recurrent dislocations
what is marfans syndrome
autosomal dominant sporadic mutation of fibrillar gene which results in tall stature with disproportionately long limbs and ligamentous laxity
what are associated features of marfans
eye problems eg glaucoma high arched palate in mouth spontaneous pneumothorax apical blebs pectus excavatum or carinatum aortic aneurysm, dissection or regurgitation mitral valve prolapse or regurg arachnodactyly (long fingers/toes) scoliosis
what is ehlers danlos syndrome
heterogenous condition (often autosomal dominant) where there is abnormal elastin and collagen formation
what is clinical features of ehlers danlos
profound joint hypermobility vascular fragility with ease of bruising joint instability scoliosis bony surgery may be required but problem cause bleeding and poor skin healing (wound dishcence and stretched scar)
what are the MSK features of down syndrome
short stature joint laxity recurrent dislocation (esp patella) which may require stabilisation atlanto-axial instability in c spine
what are muscular dystrophies
rare and usually X linked recessive hereditary disorders (only affecting boys) resulting in progressive muscle weakness and wasting
what are the two kinds of muscular dystrophy
duchenne muscular dystrophy becker’s muscular dystrophy
what is duchenne muscular dystrophy and what is its sign
defect in dystrophin gene involved in calcium transport may only be noticed when boy start to walk with difficulty standing (Gower’s sign) and going up stairs
what is consequence of duchenne muscular dystrophy
progressive muscle weakness and by age 10 he can no longer walk by age 10 progressive cardiac and respiratory failure develop with death typically in early 20s
what is beckers muscular dystrophy
similar to DMD but milder so affected boys able to walk into teens and may survive into 30s or 40s
although these only occur in boys due to X linked inheritance, can vvvvvvv occasionally happen in girls, when
if gets one faulty gene on one chromosome and the girl lacks a second X chromosome entirely or if the second X chromosome has sustained serious damage
how are muscular dystrophies diagnosed
confirmed by raised serum creatinine phosphokinase abnormality on muscle biopsy
how is muscular dystrophies treated
physiotherapy, splintage and deformity correction may prolong mobility severe scoliosis may be corrected by spinal surgery
