children's orthopaedics Flashcards
how are flat bone developed -just name
intramembranous mesenchymal cells-> bone
how are long bone developed- just name
endochondral mesenchymal -> cartilage -> bone
steps of intramembranous ossification
- condensation of mesenchymal cells-> differentiate into osteoblasts and form ossification centre
- secreted osteoid traps osteoblast which becomes osteocytes
- trabecular matrix and periosteum form
- compact bone develops superficial to cancellous bone. Blood vessels condense into red bone marrow
what is primary ossification centres of long bone formation- and when does it occur
pre-natal bone growth through endochondral ossification from central part of bone
what is secondary ossification centres of long bone formation
post-natal after primary ossification centre.
steps of endochondral primary ossification
- mesenchymal differentiation at primary ossification centre (POC) (in middle of bone diaphysis)
- cartilage model of future bony skeleton forms
- capillaries penetrate cartilage
a)calcification at POC form spongy bone
b)perichondrium transforms into periosteum - cartilage and chondrocytes continue to grow at bone ends
- secondary ossification centre develops
secondary endochondral ossification steps
Long bone lengthening at physis
Epiphyseal side – hyaline cartilage divide, forming hyaline cartilage matrix
Diaphyseal side – Cartilage calcifies+ dies. Then replaced by bone
difference between children’s and adults skeleton
elasticity
physis
healing speed
remodelling
3 issues with elasticity
Plastic deformity
– Bone deformity persists after force removed.- no cortices fractured
Buckle fracture
– One side of the bone bends, raising a little buckle, without breaking the other side of the bone.
Greenstick
One cortex fractures but does not break the other side
cause of increased elasticity
Increased density of haversian canals
age of girl and boy when growth stops and physis closes
Girls 15-16
Boys 18-19
what can physeal injuries lead to
growth arrest and deformity
what is developmental dysplasia of the hip
head of the neonatal femur is unstable to the acetabulum
risk factor of DDH
female
first born
breech
DDH:
Examination and investigation
baby check
US-0-4month
x-ray-after 4 months
DDH treatment
pavlik harness 6months
if failed/6-18months:
MUA+ closed reduction and spica
proper name for clubfoot and cause
congenital talipes equinovarus
deformity from muscle contracture
gene cause and commonest ethnicity to have club foot (congenital talipes equinovarus)
PITX1 gene
Hawaiians
symptoms of clubfoot
CAVE
Cavus –high arch
Adductus of foot: Tight tib post and ant
Varus: Tight tendoachillies,
Equinous(toe pointing down): tight tendoachilles
clubfoot treatment
ponseti method- series of casts to correct deformity
what is achondroplasia
G380 mutation ofFGFR3 gene
inhibition of chondrocyte proliferation in physis
defect in endochondral bone formation
signs of achondroplasia
Rhizomelic dwarfism
Humerus shorter than forearm
Femur shorter than tibia
Normal trunk
Adult height of approx. 125cm
osteogenesis imperfecta (brittle bone disease)
cause
decrease T1 collagen
-less secretion/abnormal collagen production
leading to insufficient osteoid production
effects of osteogenesis imperfecta on bone and non-ortho symptoms
Bones
Fragility fractures, Short stature, Scoliosis
Non-orthopaedic
Blue Sclera, brown soft teeth
Hypermetabolism
paediatric fractures checklist
PAID
pattern
anatomy
intra/extra-articular
Displacement
salter-harris
5 types of pattern in PAID
transverse
oblique
spiral
comminuted
avulsion
green stick
plastic deformity
buckle fracture
anatomy in PAID
Ie. name of bone, proximal third, middle third or distal third
intra/extra-articular of PAID–what kind of bone healing is preferred and why
Primary bone heading
-preferred in intra-articular fracture as minimise risk of post traumatic arthritis
secondary bone healing
-healing by callus
4 types of displacement in PAID
displaced
angulated
shortened
rotated
salter Harris classification for physeal injuries
- Physeal Separation
- Fracture traverses physis and exits metaphysis (Above)
- Fracture traverses physis and exits epiphysis (Lower)
- Fracture passes Through epiphysis, physis, metaphysis
- Crush injury to physis
growth arrest risk in relation to salter harris and most common type
risk increases from 1 to 5
type2 = most common
growth arrest of whole physis vs partial
Whole physis – limb length difference
Partial – angulation as the non affected side keeps growing
growth arrest treatment
limb length correction
a) shorten long side
b) lengthen short side
angular deformity
a)stop growth of unaffected side
b) reform bone (osteotomy)
reduce- example of closed reduction
gallows traction - holding skin- long bone of lower limb can be reduced
preferred restrict method
external -splints/plaster are preferred over internal
as kids have a great healing potential
septic arthritis treatment
surgical washout of the joint to clear the infection
septic arthritis- kocher’s classification
non weight bearing
ESR 40+
WBC 12,000+
Temp 38+
transient synovitis diagnosis and treatment
- exclude septic arthritis
Is a inflamed joint in response to a systemic illness
antibiotics
perthes disease
Idiopathic necrosis of the proximal femoral epiphysis
Usually 4-8 years old boys.
doesn’t affect 10+
SUFE- commonest in? Associated with?
Treatment?
Obese adolescent male
10+ (12-13 y.o)
associated with hypothyroidism/hypopituitarism
treat: operative fixation to prevent further slip and minimise LT growth issues
