Paediatric Orthopaedics - the big three

Question 1

What are the big three?

Answer 1

DDH
Perthes disease
SUFE

Question 2

How common is DDH?

Answer 2

0.24%
6X more common in girls
More common in L hip

Question 3

In which groups of people is DDH more common?

Answer 3

First born 
Oligohydramnios (decreased uterine space)
Breech presentation 
FH
Other lower limb deformities

Question 4

What is DDH?

Answer 4

Congenital malformation affecting the femoral head/acetabulum –> hip instability, subluxation of femoral head, hip dislocation etc.

Question 5

How do you notice DDH?

Answer 5

Newborn screening
<6m: asymptomatic, barlow sign, ortolani sign

6-18m: inability to abduct hip, assymetrical gluteal folds

> 18m: hip pain and pain referred from hip to knee/ant thigh, hip deformity, waddling/trendlenburg gait, leg length discrepancy

Question 6

What is barlow sign?

Answer 6

Hip clunks as it is dislocated during flexion & adduction with downwards pressure

Question 7

What is ortolani sign?

Answer 7

Palpable clunk caused by hip reduction when hip flexed and abducted while applying upward pressure

Question 8

What is piston motion sign?

Answer 8

Hip moves up and down like a piston cause it is not in the acetabulum properly

Question 9

How do you diagnose DDH?

Answer 9

Screening
Hip USS if less than 4 months
Hip Xray if older than 4 months

Question 10

What X-Ray findings might you see in DDH?

Answer 10

Disrupted Shenton’s line (medial border of femoral neck to lower border of superior pubic ramus)
Ossified nucleus of femoral head lies at Hilgereiner’s line (line through triradiate cartilage of acetabulum)
Ossified nucleus of femoral head lies lateral to perkins line (vertical line drawn perpendicular through lateral point of acetabulum)

Question 11

How do you Mx DDH?

Answer 11

<3m - simple splint
3-12m - closed reduction and spica cast
>1y open reduction and capsule reefing 
>18 months open reduction and femoral shortening
>6y and bilateral leave alone
>10y and unilateral leave alone

Older the children the poorer the results

Question 12

What is typical presentation of Legg-Calve-Perthes Disease?

Answer 12

Boy
Primary school age
Short stature
Limp 
Knee pain on exercise
Stiff hip joint
Systemically well

Question 13

How do you screen for DDH?

Answer 13

Clinical exam only picks up 40%

Question 14

What is the aetiology of Perthes disease?

Answer 14

Avascular necrosis of femoral head due to mismatch between rapid growth of femoral epiphyses and slower BS to area

Genetic factors, bleeding disorders, repetitive microtrauma

Question 15

4 stages of Perthes disease seen on a radiograph

Answer 15

4 Waldenstorm stages

• Initial stage
• Fragmentation stage
• Reossification stage
• Healed stage

Question 16

How do you Rx Perthes?

Answer 16

Maintain hip motion
Analgesia
Restrict painful activities
‘Supervised neglect’ in most cases
‘Containment’ - Consider osteotomy in
selected groups of older children (>7)
Prognosis good onset <9y

Question 17

What is SCFE?

Answer 17

Slipped capital femoral epiphysis aka SUFE

Question 18

Who does SUFE tend to affect?

Answer 18

Teenage boys (9-14)

Question 19

How is SUFE classified?

Answer 19

Acute vs chronic (3wks)

Stable vs unstable (stable = wt bear, unstable cant weight bear)

Question 20

What occurs in SUFE?

Answer 20

Usually presents after minor trauma

Displacement through the GP, with the epiphysis always sliding down and back

Question 21

Typical presentation of SUFE

Answer 21

• Boy
• 10-16yrs
• Overweight
• Limp
• Pain groin, knee or ant. thigh

Externally rotated posture + gait
Reduced IR, especially in flexion

Question 22

What are risk factors for SUFE?

Answer 22

Increasing load as well as weak physis

Adolescence, delayed bone age, increasing weight (obesity)

Question 23

What are the secondary causes of SUFE?

Answer 23

Hypothyroidism
Hypogonadism
Trauma
GH therapy

Question 24

How do you Ix SUFE?

Answer 24

Plain Xray

Best seen on lat view/frog leg

Question 25

What is the pathology of SUFE?

Answer 25

Displacement through hypertrophic zone

Metaphysis moves anterior and proximal

Question 26

How do you Mx SUFE?

Answer 26

Avoid weight bearing activities

Urgent surgical fixation with pinning of femoral head and prophylactic fixation of contralateral hip

Question 27

What are complications of SUFE?

Answer 27

AVN
Chondrolysis
Deformity
Early OA

Question 28

What is the prognosis of SUFE?

Answer 28

Stable slips - low risk AVN

Unstable slips - high risk AVN

Question 29

What are your differentials for painless limp, painful knee follows, reduced abduction and leg length is equal?

Answer 29

TS
Infection 
SUFE
Missed DDH
JIA
Lymphoma
Perthes