Paediatric Orthopaedics - The Big 3

Question 1

What does DDH stand for?

Answer 1

Developmental dysplasia of the hip

Question 2

Describe the epidemiology of DDH in terms of ethnicity, sex and which hip is more commonly affected?

Answer 2

• Different incidence in different parts of world, most prevalent in Eskimo’s and least in northern Europe
• Girls:boys 6:1
• Left hip more commonly affected than right

Question 3

What are risk factors for DDH?

Answer 3

• First born
• Oligodydramnios
  
  • Reduced fluid within the uterus
• Breech presentation
• Family history
• Other lower limb deformity
• High birth weight

Question 4

What is oligodynamics?

Answer 4

• Reduced fluid within the uterus

Question 5

What investigations are done for DDH?

Answer 5

X-ray is not done due to reducing x-ray exposure, and it would show things too late anyway due to femur not ossifying until 3 months

Investigation:

• USS
• Ortolanis sign- flex hip @ 90 degrees & then abduct
• Barlows sign- adduct the hip to dislocate it

Question 6

What does the treatment of DDH depend on?

Answer 6

Age of patient

Question 7

What is the treatment for DDH?

Answer 7

• If <3 months
  
  • 90% respond to splint
• 3 months to 1 year
  
  • Closed reduction and spica cast
• >1 year
  
  • Open reduction and capsule reefing
• >18 months
  
  • Open reduction with femoral shortening with or without peri-acetabular osteomy
• >6 years and bilateral
  
  • Leave alone
• >10 years and unilateral
  
  • Leave alone

Question 8

How does the prognosis of DDH with treatment change with age?

Answer 8

The older the child the poorer the result

Question 9

Is any screening done for DDH in the UK?

Answer 9

Selective US screening is done in UK:

• Every baby examined at birth
• US may follow if indicated

Question 10

What is the aetiology of perthes disease?

Answer 10

• Pathologically avascular necrosis of hip
• Possible relationships to
  
  • Coagulation tendency
  • Repeated minor trauma
• Familial
• Classically low social status

Question 11

Describe the epidemiology of perthes disease in terms of sex and age?

Answer 11

• M>F
• Primary school age

Question 12

What are the clinical features of perthes disease?

Answer 12

• Limp
• Knee pain on exercise
• Stiff hip joint
• Systemically well

Question 13

What investigation is done for perthes disease?

Answer 13

• X-ray
  
  • Four Waldenstrom stages

Question 14

What impacts the prognosis of perthes disease?

Answer 14

• Younger age at presentation do better
• Proportion of head involved
• Herring grade

Question 15

What is the treatment of perthes disease?

Answer 15

• Maintain hip motion
• Analgesia
• Restrict painful activity
• Consider osteotomy in selected groups of older children (>7 years)

Question 16

What does SUFE stand for?

Answer 16

Slipped upper femoral epithysis

Question 17

Describe the epidemiology of SUFE in terms of sex and age?

Answer 17

• M>F
• Many overweight
• Age 9-14 years

Question 18

How can SUFE be classed?

Answer 18

• Acute v chronic
• Magnitude of slip (angle or proportion)
• Stable v unstable
  
  • Unstable is unable to weight bear (poor prognosis)
  • Stable is able to bear weight (good prognosis)

Question 19

What is the difference between stable and unstable SUFE?

Answer 19

• Stable v unstable
  
  • Unstable is unable to weight bear (poor prognosis)
  • Stable is able to bear weight (good prognosis)

Question 20

How is the magnitude of SUFE classified?

Answer 20

Magnitude is classified by ratio of width of femur to amount of slip:

• Mild <1/3
• Moderate 1/3-1/2
• Severe >1/2

Question 21

Describe the pathology of SUFE?

Answer 21

• Displacement through hypertrophic zone
• Metaphysis moves anterior and proximal

Question 22

What are the clinical features of SUFE?

Answer 22

• Pain in hip or knee
• Externally rotated posture and gait
• Reduced internal rotation, especially in flexion
• Plain x-rays
  
  • Best seen on lateral x-rays

Question 23

What investigations are done for SUFE?

Answer 23

• X-ray
• Slip can be identified early using Trethowan;s sign on AP film

Question 24

What is the treatment for SUFE?

Answer 24

• Operative
  
  • Pinned in situ if stable
  • Open reduction if severe unstable slips
    
    • AVN high risk

Question 25

What are possible complications of SUFE?

Answer 25

• AVN
  
  • Stable slips have low risk, unstable slips have high risk
• Chrondolysis
• Deformity
• Early OA
• Limb length discrepancy
• Impingement