Paediatric Orthopaedics Flashcards
what is the colloquial name for Osteogenesis Imperfecta?
brittle bone disease
what is osteogenesis imperfecta a defect of?
a defect of the maturation and organisation of type 1 collagen
what type of collagen accounts for most of the organic composition of bone?
type 1 collagen
what type of inheritance are the majority of osteogenesis imperfect cases?
autosomal dominant
what are the 4 main clinical signs/symptoms of autosomal dominant osteogenesis imperfecta?
- multiple fragility fractures of childhood
- short stature with multiple deformities
- blue sclerae
- loss of hearing
rarer cases of osteogenesis imperfecta are aurosomal recessive, how do these present?
either fatal in perinatal period
or
associated with spinal deformity
how do fractures tend to heal in a patient with osteogenesis imperfecta?
heal with abundant but poor quality callus
how are fractures in patients with osteogenesis imperfecta treated?
with splintage, traction or surgical stabilisation
what is the medical term for short stature?
skeletal dysplasia
what is skeletal dysplasia caused by?
abnormal development of bone and connective tissue
is skeletal dysplasia hereditary?
can be
can also be a sporadic mutation
what is a proportionate short stature compared to a disproportionate short stature?
proportionate: limbs and spine proportionally short
disproportionate: limbs proportionally shorter/longer than spine
what is the commonest type of skeletal dysplasia?
achondroplasia
what type of inheritance is achondroplasia?
can be autosomal dominant but most cases are sporadic
what are the 5 key features of achondroplasia?
disproportionately short limbs (proximal limbs are short- rhizomelic disproportion) prominent forehead widened nose lax joints mental development is normal
what are congenital connective tissue disorders?
genetic disorders of mainly type 1 collagen synthesis found in bones, tendons and ligaments
what is the difference between osteogenesis imperfecta and connective tissue disorders in terms of what collagen is affected?
osteogenesis imperfecta- type 1 collagen of the bones affected
coonnective tissue disorders- soft tissues more than bone
what is the medical term for ‘double jointed’? (ie when a person has hypermobility of joints)
generalised (familial) joint laxity
[connective tissue disorder]
how is generalised (familial) joint laxity usually inherited?
autosomal dominant
what are people with generalised (familial) joint laxity more prone to?
soft tissue injuries (esp ankle sprains) and recurrent dislocations (esp shoulder and patella)
what type of inheritance is Marfan’s synrome? [connective tissue disorder]
autosomal dominant or sporadic
what gene is mutated in marfan’s syndrome?
fibrillin gene
what are the 3 main features of a patient with Marfan’s syndrome?
tall stature
disproportionately long limbs
ligamentous laxity
what are the 7 main associated features of Marfan’s syndrome? (ie on top of: tall stature, long limbs and laxity)
- high arched palate
- scoliosis
- flattening of the chest (pectus excavatum)
- eye problems
- aortic aneurysm
- cardiac valve incompetence
- pneumothorax
what type of inheritance is Ehlers-Danlos syndrome? [connective tissue disorder]
often autosomal dominant
what macrostructures are abnormally formed in ehlers-danlos syndrome?
abnormal elastin and collagen formation
what are the 4 main features of ehlers-danlos syndrome?
- joint hypermobility
- vascular fragility (easy bruising)
- joint instability
- scoliosis
why can skin healing be poor in a patient with ehlers-danlos syndrome?
abnormal collagen and elastni causes stretched scars or wound dehiscence
what defect is involved in duchenne muscular dystrophy?
defect in dystrophin gene (involved in calcium transport)
when does death occur typically in duchenne muscular dystrophy?
early 20s
how is diagnosis of duchenne muscular dystophy confirmed?
raised serum creatinine phosphokinase
abnormalities on muscle biopsy
where is the growth plate of bones?
physis
-just above metaphysis (neck)
where does primary ossification occur and why?
occurs in diaphysis because this is where the blood supply first develops
where does secondary ossification occur and why?
occurs in the epiphysis
because a second blood supply starts to develop within the head
how do embryonic bones start off? (ie what are they made of?)
purely cartilage
-no ossification at all
compare the periosteum in children to adults?
children’s periosteum is very thick, becomes thinner in adults
why are children prone to get septic arthritis?
because the blood supply is quite sluggish in the blood vessels at the growth plate
what is the Heuter-Volkmann law?
the rate of the growth of a bone will be affected by pressures on it’s axis:
increased pressure inhibits growth, decreased pressure accelerates growth
what will fractures do to the growth of a bone?
stimulate growth
what will an increased blood supply do to a bone?
stimulate growth
what type of gait do children have?
broad-based gait
why do children have a broad-based gait?
legs are wider apart for increased support
at what age is an adult gait pattern established?
about 8 years old
when are flat feet abnormal?
when they are stiff or painful
what arch is lost in flat feet?
medial longitudinal arch
what tendon appears to be tight in flat-footed patients?
tight achilles tendon
what 2 muscles form the achilles tendon?
gastrocnemius and soleus tendons
what is normal median longitudinal arch development?
arch becomes increasingly developed as age increases (until after 30’s where foot becomes more flat again)
what are the 3 main causes of in-toeing?
- femoral neck anteversion
- internal tibial torsion]- metatarsus adductus
what is femoral neck anteversion?
femoral neck is pointed forwards
what is internal tibial torsion?
inwards twisting of the tibia (knee cap in normal position)
what is metatarsus adductus?
front half of foot twisted inwards
what is the natural history of femoral neck anteversion, internal tibial torsion or metatarsus adductus?
usually all resolve with time
how do you assess a child for femoral neck anteversion?
get child to lie prone with knees flexed
check both internal and external rotation and note angles
when does femoral neck anteversion usually present?
after the age of 4
by what age should femoral neck anteversion have improved by?
age 12
when does internal tibial torsion usually present?
before the age of 4
how do you asses a child for metatarsus adductus?
draw a line between heel and mid foot- see which toes the line exits between
what are the benefits of slight in-toeing?
able to run faster
what tibial deformity causes infantile bow legs?
medial tibial torsion
when are bow legs normal?
below 2 years: normal
if a patient has bow legs after 2 years what should you consider?
skeletal dysplasia
-check if patient’s height is below 2nd standard deviation
when should you refer a patient with bow legs?
if:
- assymetrical
- not resolving (ie older than 2 years)
- painful
- height
when do knock knees usually peak?
3.5 years old
when do you refer for knock knees?
- if asymmetrical
- if inter-malleolar distance is >8cm (when knees are together) at 11 years
the impingement of what nerve is most associated with adolescent anterior knee pain localised to the patella?
obturator nerve impingement at hip joint
what is clubfoot? (CTEV)
a congenital deformity of the foot where the foot is plantar-flexed and the forefoot is supinated and has a varus alignment
(stiff in thie position)
who is clubfoot common in-boys or girls?
boys
what is more likely- unilateral or bilateral clubfoot?
50% either way
what is postural talipes?
a congenital foot deformity which looks like clubfoot but foot easily doorsiflexes
what is the treatment of postural talipes?
physiotherapy and stretching
what is the natural history of club foot?
doesn’t improve
gets worse
what is the treatment of club foot?
Ponseti splintage ASAP
plaster cast
+ boots and bar (23 hours per day for 3 months then nightly wearing until age of 4)
[most children also require a tenotomy of the achilles tendon]
what is rocker bottom feet?
a congenital deformity of the foot where the foot appears externally rotated, very prominent calcaneus
(mirror opposite of club foot)
what is cerebral palsy caused by?
an insult to the growing brain
ie an injury to the brain which occured before myelination
what is spasticity?
abnormal rate-dependant increase in muscle tone/stiffness
antagonistic mechanisms can fail
what are the 3 treatment options of spasticity?
- muscle relaxers (eg benzodiazepines, baclofen)
- botulinum toxin (paralyses muscle plates)
- selective dorsal rhizotomy
what are the 3 types of gait problems in cerebral palsy?
- primary
- secondary
- tertiary
what are primary gait problems in cerebral palsy?
gait problems directly due to the initial CNS injury
ie loss of selective muscle control/loss balance mechanisms/abnormal tone
what are secondary gait problems in cerebral palsy?
gait problems indirectly due to the initial CNS injury- result from growth abnormalities
(ie scoliosis, hip sublaxation, torsion)
what are the tertiary gait problems in cerebral palsy?
gait problems due to the coping response of the patient to the muscle abnormalities and the growth abnormalities
the GMFCS (gross motor function classification system) is used to classify the degree of cerebral palsy, what does a higher GMFCS score mean?
higher risk of dislocation
what can cerebral palsy patients with a GMFCS score of 1-3 do that patients with a GMFCS score of 4+ not do?
walk
are cavus feet normal or pathological?
usually pathological
what type of disorder is cerebral palsy?
neuromuscular disorder
when is the onset of cerebral palsy?
before 2-3 years of age
what are the 7 main causes of cerebral palsy?
- genetic problems
- brain malformation
- hypoxia during birth
- intrauterine infection in early pregancny
- prematurity
- intra-cranial haemoorhage
- meningitis
what are the 3 main causes of brachial plexus injury during vaginal delivery?
- large babies
- twin deliveries
- shoulder dystocia
what is shoulder dystocia?
difficult delivery of the shoulder after the head with compression of the shoulder on the pubic symphysis
what is the commonest type of obstetric brachial plexus palsy?
Erb’s palsy
what nerve roots are damaged in Erb’s palsy?
C5, C6
In Erb’s palsy, what muscles lose their motor innervation?
- deltoid
- supraspinatous
- infraspinarous
- biceps
- brachialis
why is physiotherapy required in Erb’s palsy fairly early on?
to prevent contractures
what is prognosis of Erb’s palsy predicted by?
the return of bicpes function within 6 months
if there is no recovery of motor innervation, what is the treatment of Erb’s palsy?
surgical release of contractures
tendon transfers
what nerve roots are damaged in Klumpske’s palsy?
C8 and T1
what is Klumpske’s palsy (obstetric brachial plexus palsy) caused by?
foreceful adduction
In Klumpske’s palsy, what muscles lose their motor innervation?
intrinsic hand mucles
+/- fingers, wrist flexors
why might a patient with Klumpske’s palsy also have Horner’s syndrome?
due to disruption of the first sympathetic ganglion from T1
In Klumpske’s palsy what position are the fingers typically in?
flexed
which palsy has a better prognosis: Erb’s palsy or Klumpske’s palsy?
(ie more likely to recover motor function)
Erb’s palsy
what is the natural progression of knee aligment in a child?
at birth, children have varus knees (bow legs) which become neutrally aligned at 14 months.
This progresses to valgus (knock knees) at 3 years and then slowly regresses
what is in-toeing?
a child who, when walking or standing, have feet that point towards the midline
why as age develops does the median longitudinal arch develop?
due to muscles developing
what is flexible flat footedness related to?
ligamentous laxity
what is the underlying bony abnormality that causes rigid flat footedness?
tarsal coalition
bones of the hindfoot connected by an abnormal bony or cartilaginous connection
what is developmental dysplasia of the hip?
disclocation or sublaxation of the femoral head during the perinatal period
-this affects the subsequent development of the hip joint
who more commonly gets developmental dysplasia of the hip- girls or boys?
girls
which hip is more likely to be involved in developmental dysplasia of the hip?
left hip
what are the 5 main risk factors for developmental dysplasia of the hip?
- family history
- breech presentation
- first born babies
- down’syndrome
- other congenital disorders
what happens to developmental dysplasia of the hip if left untreated?
acetabulum becomes very shallow,
in severe ases a false acetabulum occurs superior to the original one creating a shorter lower limb
what 2 manoeuvres test the presence of developmental dysplasia of the hip?
ortolani’s test
barlow’s test
what is ortolani’s test?
tests the presence of a dislocated hip by reducing the hip with abduction and anterior displacement
-if positive, a click/clunk noise should be made
what is barlow’s test?
tests the presence of a dislocatable hip with flexion and posterior displacement
-if positive a click/clunk noise should be made
what are the 3 main signs of developmental dysplasia of the hip?
- shortening of limb
- asymmetric groin/thigh creases
- click/clunk with Ortolani or Barlow manoeuvres
what is the investigation of choice for a suspected developmental dysplasia of the hip in a child below 4-6 months?
ultrasound
what is the investigation of choice for a suspected developmental dysplasia of the hip in a child above 4-6 months?
x-ray
why can x-rays not be used in the early diagnosis of developmental dysplasia of the hip?
femoral head is unossified
how are mild cases of developmental dysplasia treated? (ie slightly shallow acetabulum, midly dislocatable but reduced hip)
close observation with serial examination and ultrasound to ensure hip remains reduced
how are servere cases of developmental dysplasia treated? (ie dislocated or persistenly unstable hips)
reduced and held with a special harness (Pavlik harness)
what position does a Pavlik harness keep the child in?
a comfortable flexion and abduction of the thighs
what can over-flexing and abducting the hip causes?
avascular necrosis
how are children with developmental dysplasia of the hip with persistent dislocation (even after Pavlik harness use) treated?
open reduction + osteotomy to shorten/rotate femur and deepen/re-orientate the acetabulum
what is the most common cause of hip pain in childhood?
transient synovitis
what is transient synovitis?
a self-limiting inflammation of the synovium of a joint
what is the most common joint to get transient synovitis?
hip joint
what does transient synovitis commonly occur shortly after?
an upper respiratory tract infection (usually viral)
who tends to get transient synovitis?
boys between 2-10
girls are more rarealy affected
what is Perthes disease?
a childhood disorder in which the blood supply to the femur head is transiently inadequate resulting in avascular necrosis and subsequent abnormal growth or collapse
how do you exclude perthes disease when suspecting transient synovitis?
X-ray
how do you exclude septic arthritis when suspecting transient synovitis?
clinical picture (less pain and bigger R.O.M than septic arthritis) lower CRP than septic arthritis
what is the treatment of transient synovitis?
NSAIDs and rest
what should be done if there is no resolution of suspected transient synovits within a few weeks?
look for another cause for the hip pain
who tends to get Perthes disease?
boys aged 4-9
especially of short stature who are very active
what 2 main factors determine the prognosis of subsequent remodelling of the femoral head in a child with Perthes disease?
- age of onset (younger = better prognosis)
- amount of femoral head collapse
how do children affected with transient synovitis of the hip present?
limp and reluctance to weight bear on affected side
how do children with Perthes disease present?
pain and limp
what is the first clinical sign of Perthes disease and how does this progress?
first sign- loss of internal rotation
followed by loss of abduction
followed by positive trendellenburgs test
most cases of Perthes disease are unilateral, in a patient with bilateral disease what should you consider?
possible underlying skeletal dysplasia or thrombophilia
what is the treatment of Perthes disease?
regular x-ray observation
avoidance of physical activity
occasionally osteotomy of femur or acetabulum if femoral head has subluxed
who tends to get a slipped upper femoral epiphysis?
overweight pre-pubertal boys
what 2 conditions may predispose to a slipped upper femoral epiphysis?
hypothyroidism
renal disease
what is a slipped upper femoral epiphysis?
femoral head epiphysis slips inferiorly in relation to the femoral neck
what are the types of slipped upper femoral epiphysis?
acute
chronic
acute on chronic
where can pain be felt in a slipped upper femoral epiphysis?
pain in groin
pain in knee (might present purely as this)
what is the predominant clinical sign of loss of slipped upper femoral epiphysis?
loss of internal rotations
why must a lateral view x-ray of a suspected slipped upper femoral epiphysis be obtained?
to detect mild degrees of slip
what is the treatment of slipped upper femoral epiphysis?
urgent surgery to pin the femoral head to prevent further slippage
what is jumper’s knee?
patellar tendonitis
what is the treatment for patellar tendonitis?
self-limiting
requires rest and possibly physiotherapy
why is knee extensor mechanism pain fairly common in adolescence?
body weight increases
sporting activities increase
who tends to get adolescnet nterior knee pain-M or F? (patellofemoral dysfunction)
girls
what are the subtle skeletal predispositions to patellofemoral dysfunction- adolescent anterior knee pain?
genu valgum
wide hips
femoral neck anteversion
what is chondromalacia?
softening of the hyaline cartilage of the patella
in adolescent anterior knee pain what might have happened to the hyaline cartilage of the patella?
chondromalacia patellae
(softening of the patellar hyaline cartilage
what is the treatment of adolescent anterior knee pain?
self-limiting
physiotherapy to rebalance msucles
resistant cases may require surgery to shift forces on patella (tibial tubercle transfer)
what joints are affected in clubfoot? (CTEV)
joints between talus, calcaneus and navicular
what are the 5 main risk factors for clubfoot?
- family history
- breech presentation
- oligohydramnios (low amniotic fluid content)
- skeletal dysplasia
- male
what are mobile/flexible flat feet?
medial arch reforms with dorsiflexion of great toe
what are rigid flat feet?
arch remains flat regardless of load or great toe dorsiflexion
if a flat foot is described as rigid, what is the most possible cause of the flat foot?
tarsal coalition
in children with painful scoliosis, what urgent investigation should be done?
MRI
how many cases of slipped upper femoral epiphysis are bilatera?
1/2
if a flat foot is described as dynamic (ie present when the foot is weight-bearing only) what is the most possible cause?
underlying ligamentous taxity
what pain may a SUFE solely present with?
pain in the knee
what is a greenstick fracture?
a fracture where one side breaks and the other side only bends
what is a torus fracture?
an incomplete fracture characterised by bulging of the cortex
also known as a buckle fracture
what is plastic deformation?
when an incomplete fracture (ie greenstick fracture) bends and remains in this bowed position instead of returning to normal position
