Children hip disorder

Question 1

when does developmental dysplasia of the hip present

Answer 1

birth - 2 years

Question 2

when does perthes present

Answer 2

4-8 years

peak age 6

Question 3

when does SUFE present

Answer 3

10-16 years

peak age 12/13

Question 4

development of the acetabulum

Answer 4

triradiate cartilage, ossifies over time so its fused and bony in adults
fused from ilium, ischium and pubis

Question 5

why aren’t hip X-rays useful in younger patients

Answer 5

femoral head still cartilinagous so doesn’t show up

Question 6

what is H line on Xray

Answer 6

runs between left and right triradiate cartilages

horizontal shows symmetry

Question 7

what vertical line helps show whether hip is dysplased

Answer 7

to perpendicular lines to H line (the P line)

Question 8

what is DDH

Answer 8

abnormal development resulting in dysplasia and possible subluxation or dislocation of hip

Question 9

What are signs of DDH

Answer 9

dysplasia
shadow or underdeveloped acetabulum
subluxation
dislocation

Question 10

what is the most common orthapaedic disorder in newborns

Answer 10

DDH

Question 11

what factors allow hip to become dysplastic

Answer 11

capsular laxity and mechanical factors

Question 12

what joint is it most common in

Answer 12

female (more laxity) 
left hip (way the baby lies in utero)

Question 13

in what populations is DDH most commonly seen

Answer 13

native Americans
laplanders
due to the way they carry children in a papoose

Question 14

what stimulates normal acetabular growth

Answer 14

correctly positions femoral head

absent in SSH, hip becomes sublaxed/dislocated

Question 15

what is the pathophysiology of DDH

Answer 15

initial instability caused by maternal and fatal laxity, genetic laxity and intrauterine and post natal malpositioning

Question 16

pathoanatomy of DDH

Answer 16

initial instability leads to dysplasia leading to gradual dislocation

Question 17

why do DDH patients get trelenberg pathology

Answer 17

shortened leaver arm means that the abductors need to work harder

Question 18

risk factors for DDH

Answer 18

first borns 
6x more common in females 
breech presentations 
family history 
oligohydramnios

Question 19

patient presentation in DDH

Answer 19

abnormality on screening (early)
limping child (late)
pain later in life

Question 20

2 clinical tests that indicate DDH

Answer 20

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

Question 21

what quadrant should the developing hip lie in (in relation to the H line)

Answer 21

medial inferior quadrant

Question 22

what is the early treatment for DDH

Answer 22

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

Question 23

what is the late presentation DDH treatment

Answer 23

surgery
closed reduction (put hip in the right position and cast that stays on for 3 months)
open reduction + osteotomies

Question 24

what is reactive synovitis

Answer 24

painful inflamed hip joint after a viral illness
pain present with pain referred to the knee
patient lies with flexed/externally rotated hip

Question 25

how is reactive synovitis diagnosed

Answer 25

kochers criteria
distinguished between reactive synovitis and septic arthritis
higher score - more likely to be septic arthritis

Question 26

Treatment for reactive synovitis

Answer 26

self limiting condition
analgesia/NSAIDS
repeat review/admission if concern

Question 27

septic arthritis of the hip presentation

Answer 27

short duration of symptoms
unable to weight bear and hip/groin pain
pyrexial, haemodynamically stable

Question 28

why is septic arthritis a surgical emergency

Answer 28

high bacterial load that causes sepsis
destruction of the joint due to proteolytic enzymes
potential for osteonecrosis of the hip due to increased pressure

Question 29

what causes septic arthritis

Answer 29

direct inoculation from trauma/surgery
hematogenous seeding
extension from adjacent bone
osteomyelitis

Question 30

most common causative organism for septic arthritis

Answer 30

staph aureus

neonates get strep
(Iv drug users get atypical)

Question 31

treatment for septic arthritis

Answer 31

open surgical wash out
samples prior to antibiotics
repeat wash out if not improving

Question 32

what is perthes disease

Answer 32

avascular necrosis of the hip (idiopathic)

most common in 4-8 y/o

Question 33

risk factors for perthes disease

Answer 33

family history
low birth weight
second hand smoke
asian, Inuit and Central European decent

Question 34

pathophysiology of perthes disease

Answer 34

osteonecrosis occurs secondary to femoral head blood supply disruption
revascularasation follows with sbsequent reabsorption and later collapse
leads to remodelling after collapse

Question 35

proposed mechanisms for perthes disease

Answer 35

possible association with clotting factors

repeated subclinical trauma and mechanical overload

Question 36

what are the stages of perthes disease

Answer 36

initial
fragmentation
reossification
remodelling

Question 37

is perthes disease unilateral

Answer 37

yes

Question 38

what is SUFE (slipped upper femoral epiphysis)

Answer 38

proximal femoral physic leads to slippage of the metaphysic relative to the epiphysis

Question 39

risk factors for SUFE

Answer 39

males
obesity 
age 10-16 
endocrine disorders 
rapid period of growth

Question 40

cause of SUFE

Answer 40

epiphysis can’t hold force of bodyweight (ice cream falls of cone)

Question 41

treatment for SUFE

Answer 41

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