context week 3 Flashcards
what is osteogenesis imperfecta
brittle bone disease, defect in maturation and organisation of Type 1 collagen.
what are the two types of osteogenesis imperfecta
autosomal dominant- mutliple fractures in childhood, short stature with deformity, blue sclera, loss of hearing
autosomal recessive - rarer, fatal prenatal or associated spinal deformity
(many genetic changes de novo)
what is osteogenesis imperfecta sometimes mistaken for
child abuse
what is shown on X-rays of osteogenesis imperfecta
mild cases have relatively normal X-rays with Hx of low energy fractures. [sometimes “psuedofractures”]
healing ability of osteogenesis imperfecta
fractures tend to heal with abundance but poor quality callus formation
treatment for osteogenesis imperfecta
splintage, traction or surgical stabilisation.
some cases can develop progressive deformity which may require multiple osteotomies and intramedullary stabilisation for correction.
what is skeletal dysplasia?
medical term for short stature (Dwarfism not used anymore).
why does skeletal dysplasia occur?
genetic error, abnormal connective tissue/ bone occurs.
what are proportionate and disproportionate statures in skeletal dysplasia?
proportionate - limb same size/proportional to spine
disproportionate - limbs and spine not proportional.
what is the commonest skeletal dysplasia? give some features of it.
achondroplasia.
autosomal dominant (80% spontaneous disease). lax ligaments and normal mental development. disproportionately short limbs to spine. wide nose, prominent forehead.
know that there are many other types of skeletal dysplasia each with their own features. (mild/severe signs/consequences/symptoms)
-
treatment for skeletal dysplasia
genetic testing of child and family.
correct deformities and lengthen limbs.
GH therapy may be appropriate
where is type 1 and 2 collagen found
1-bone, tendon, ligaments, skin
2-cartilage
what are CTDs due to?
genetic disorders of collagen synthesis
what is generalised (familial) joint laxity
CTD. double-jointed people, 5% population, more prone to ankle sprains (soft tissue injury) and painful dislocations (rucurrent shoulder/patellar)
medical name for double jointedness
generalised (familial) joint laxity
what is marfan’s?
CTD. tall, long limbs, ligamentous laxity.
what genetic abnormality occurs in Marfan’s
autosomal dominant/sporadic mutation of fibrillin gene
what are some common signs/consquences of Marfan’s
lens dislocation, retinal detachment, glaucoma,
high arched palate,
spontaneous pnuemothroax, apical blebs,
pectus excavatum/carinatum.
aortic dissction/aneurysm/regurgitation. mitral valve prolapse/regurgitation.
long arms/legs, scoliosis, arachnodactyly.
what does EDS stand for and what causes it?
Ehlers-Danlos syndrome, heterogenous condition autosomal dominantly inherited with abnormal elastin/collagen formation.
features of EDS
profound joint hyper mobility, vascular fragility, easy bruising, scoliosis, joint instability
treatment of EDS
bone surgery (wound dehiscence common as abnormal connective tissues)
Down’s syndrome is caused by what genetic problem?
trisomy 21.
features of Downs relating to CTD
short stature, joint laxity, possible recurrent dislocation (may require stabilisation), atlanto-axial instability may occur in C-spine
general background about muscular dystrophies
Duchenne muscular dystrophy
rare, X-linked, progressive muscle weakness + wasting
DMD cause
defect in dystrophin gene involved in calcium transport
DMD presentation
initially difficulty standing/climbing stairs; Gower’s sign
age 10 can’t walk, age 20 cardiac/resp failure, dead by early 20’s
investigtions for DMD
inc serum creatinine phosphokinase, abnormalities on muscle biopsy.
treatment for DMD
physio, splintage, deformity correction may inc mobility. correct severe scoliosis by surgery
Becker’s MD vs DMD
similar to DMD but less severe. able to walk until teens and die 30/40’s
upper motor neurone problem causes what?
spasticity and hyperreflexia
lower motor neurone problem causes what?
reduced tone and reflexes
name some neuromuscular disorders
cerebral palsy, spina bifida, polio.
why does Cerebral palsy occur?
onset before 2-3 years, due to insult to immature brain (before during or after birth)
causes of cerebral palsy
genetic problem, intrauterine infection in pregnancy, brain malformation, intra-cranial haemorrhage, hypoxia at birth, meningitis, premature birth.
types of cerebral palsy
hemi/di/quadratplegic;
also spastic, ataxic and athetoid(dyskinetic)
management of cerebral palsy
physio, splintage, diazepam, baclofen, botox (botolinem toxin), surgery to correct
((((also SALT’s and carers etc…))))
spina bifida cause
congenital, two halves of posterior vertebral arch fail to fuse
spina bifida types
spina bifida OCCULTA (mild) and cystica (severe)
what is spina bifida occulta?
mild = spina bifida OCCULTA. maybe no associated problems but may get tethering of spinal cord and roots.
get high arches feet and clawed tons; some have dimple of hair on back
what is spina bifida cystica?
severe, herniated contents of spinal canal.
meninges only = meningocele
meninges + spinal cord = myelomeningocele.
may be associated with hydrocelphalus (excess CSF fluid causing inc ICP).
treating spina bifida cystica
close within 48 hours surgically (prevent infection/damage). no treatment for neurological consequences.
pathogenesis of polio/poliomyelitis
viral (poliovirus by faecal-oral route), causing lower motor neurone deficit.
polio PC
systemically unwell then 3-4 days later muscle weakness and inability to move limb/paralysis, recovery possible while some stay damaged
preventable due to vaccine
polio features and treatment
paralysis, joint deformity, growth defects, can still feel/sensory neurones fine
splintage and inc mobility.
name two developmental disorders
limb malformations, obstetric brachial plexus palsy.
examples of limb malformations
extra/absent bones, short bones, fused bones, skin/soft tissue issues.
what is syndactyly?
commonest congenital malformation (failure in apoptosis). leave or may require surgery
what is polydactyly and how to treat?
extra digit,
amputate
what is fibular hemimelia, signs and treatment
partial/complete absence of fibula
shortened limb, bowing of tibia, ankle deformity
mild= limb lengthening severe= through ankle amputation + prothesis
give examples of other limb shortening deformities
deficiency in proximal femur and tibia; radial absence/hypoplasia.
where does congenital fusion occur commonly and what treatment needed
commonest between two of the tarsal bones of the foot, may be painful in childhood indicating surgery.
who does obstetric brachial plexus palsy occur in?
0.2%, large babies/twins/shoulder dystocia
what is Erb’s palsy and common features
commonest obstetric brachial plexus palsy.
injury to C5-C6, reduced innervation in deltoid, supraspinatus, infraspinatus, biceps and brachialis.
leads to internal rotation (unopposed subscapularis) giving “waiter’s tip posture”.
treating Erb’s palsy
physic give good prognosis (90% recovery).
surgical release of contractures and tendon transfers if not recovering.
what is Klumpke’s palsy
rarer, C8-T1 affected.
forceful adduction which results in paralysis of intrinsic hand muscles +/- fingers and wrist flexors.
Klumpke’s palsy association, treatment and prgonosis
possible Horner’s syndrome (disrupt of first sympathetic ganglia from T1).
no specific treatment, 50% recovery
what is TBP ( total brachial palsy) prognosis
TBP after birth carries poorest prognosis of obstetric brachial plexus palsy’s