Children hip disorder Flashcards
when does developmental dysplasia of the hip present
birth - 2 years
when does perthes present
4-8 years
peak age 6
when does SUFE present
10-16 years
peak age 12/13
development of the acetabulum
triradiate cartilage, ossifies over time so its fused and bony in adults
fused from ilium, ischium and pubis
why aren’t hip X-rays useful in younger patients
femoral head still cartilinagous so doesn’t show up
what is H line on Xray
runs between left and right triradiate cartilages
horizontal shows symmetry
what vertical line helps show whether hip is dysplased
to perpendicular lines to H line (the P line)
what is DDH
abnormal development resulting in dysplasia and possible subluxation or dislocation of hip
What are signs of DDH
dysplasia
shadow or underdeveloped acetabulum
subluxation
dislocation
what is the most common orthapaedic disorder in newborns
DDH
what factors allow hip to become dysplastic
capsular laxity and mechanical factors
what joint is it most common in
female (more laxity) left hip (way the baby lies in utero)
in what populations is DDH most commonly seen
native Americans
laplanders
due to the way they carry children in a papoose
what stimulates normal acetabular growth
correctly positions femoral head
absent in SSH, hip becomes sublaxed/dislocated
what is the pathophysiology of DDH
initial instability caused by maternal and fatal laxity, genetic laxity and intrauterine and post natal malpositioning
pathoanatomy of DDH
initial instability leads to dysplasia leading to gradual dislocation
why do DDH patients get trelenberg pathology
shortened leaver arm means that the abductors need to work harder
risk factors for DDH
first borns 6x more common in females breech presentations family history oligohydramnios
patient presentation in DDH
abnormality on screening (early)
limping child (late)
pain later in life
2 clinical tests that indicate DDH
Barlow test
-pushing backwards to try to dislocate hip
Ortolanis test
-abducting the hips to try and relocate them, fingers push femur forward into acetabulum
what quadrant should the developing hip lie in (in relation to the H line)
medial inferior quadrant
what is the early treatment for DDH
Pavlik harness 23 hours a day for up to 12 weeks night time for a few more weeks puts the femoral head back into the acetabulum puts hit abducted and flexed
what is the late presentation DDH treatment
surgery
closed reduction (put hip in the right position and cast that stays on for 3 months)
open reduction + osteotomies
what is reactive synovitis
painful inflamed hip joint after a viral illness
pain present with pain referred to the knee
patient lies with flexed/externally rotated hip
how is reactive synovitis diagnosed
kochers criteria
distinguished between reactive synovitis and septic arthritis
higher score - more likely to be septic arthritis
Treatment for reactive synovitis
self limiting condition
analgesia/NSAIDS
repeat review/admission if concern
septic arthritis of the hip presentation
short duration of symptoms
unable to weight bear and hip/groin pain
pyrexial, haemodynamically stable
why is septic arthritis a surgical emergency
high bacterial load that causes sepsis
destruction of the joint due to proteolytic enzymes
potential for osteonecrosis of the hip due to increased pressure
what causes septic arthritis
direct inoculation from trauma/surgery
hematogenous seeding
extension from adjacent bone
osteomyelitis
most common causative organism for septic arthritis
staph aureus
neonates get strep
(Iv drug users get atypical)
treatment for septic arthritis
open surgical wash out
samples prior to antibiotics
repeat wash out if not improving
what is perthes disease
avascular necrosis of the hip (idiopathic)
most common in 4-8 y/o
risk factors for perthes disease
family history
low birth weight
second hand smoke
asian, Inuit and Central European decent
pathophysiology of perthes disease
osteonecrosis occurs secondary to femoral head blood supply disruption
revascularasation follows with sbsequent reabsorption and later collapse
leads to remodelling after collapse
proposed mechanisms for perthes disease
possible association with clotting factors
repeated subclinical trauma and mechanical overload
what are the stages of perthes disease
initial
fragmentation
reossification
remodelling
is perthes disease unilateral
yes
what is SUFE (slipped upper femoral epiphysis)
proximal femoral physic leads to slippage of the metaphysic relative to the epiphysis
risk factors for SUFE
males obesity age 10-16 endocrine disorders rapid period of growth
cause of SUFE
epiphysis can’t hold force of bodyweight (ice cream falls of cone)
treatment for SUFE
surgery
percutaneous pinning of the hip
+/- pinning of other side because there is a risk of getting bilateral
open reduction if a very severe slip
