Children's Orthopaedics - The Big 3 - DDH, Perthes, SUFE

Question 1

Is developmental dysplasia of the hip (DDH) more common in boys or girls

Answer 1

Girls 6:1

Question 2

Risk factors for DDH

Answer 2

• First born
• Beach presentation
• Oligohydramnios
• FHx
• Other LL deformities
• Increased weight

Question 3

Clinical features of DDH

Answer 3

• Ortolani’s sign
• Barlow’s sign
• Piston motion sign
• The hamstring sign

Question 4

Why are x-rays not great at detecting DDH

Answer 4

• On average the head of the femur doesn’t ossify until 3 months
• Which is too late

Question 5

Rx of DDH

Answer 5

• <3mth simple splint (90% respond)
• 3-12mth closed reduction + spica cast
• > 1yr open reduction + capsule reefing
• > 18mth open reduction + femoral shortening
• > 6yr + bilateral leave alone
• > 10yr + unilateral leave alone

Older the child the poorer the results

Question 6

How to screen for DDH

Answer 6

• Clinical exam (only picks up 40%)

- US (universal or selective)

Question 7

Typical presentation of Perthes disease

Answer 7

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

Question 8

Aetiology of Perthes disease

Answer 8

• Pathological avascular necrosis of the hip
• Possible relationship w/ coagulation tendency + repeated minor trauma
• FHx
• Classically low social class

Question 9

4 stages of Perthes disease seen on a radiograph

Answer 9

4 Waldenstorm stages

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

Question 10

Prognosis of Perthes disease

Answer 10

• Younger do better
• Proportion of head involved
• Herring grade
• The nearing the head is to the round the better the outlook (Stulberg)

Question 11

Rx of Perthes disease

Answer 11

• Analgesia
• Restrict painful activities
• Splints + physio
• Consider osteotomy in children >7yrs

Question 12

What is slipped upper femoral epiphysis (SUFE)

Answer 12

• Usually presents after minor trauma

- There is displacement through the growth plate, with the epiphysis always slipping down and back

Question 13

Risk factors for SUFE

Answer 13

-Male
-Overweight
-

Question 14

Typical presentation of SUFE

Answer 14

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

Externally rotated posture + gait
Reduced IR, especially in flexion

Question 15

How to classify SUFE

Answer 15

• Chronic vs acute
• Magnitude of slip (angle or proportion)
• Stable vs unstable

Question 16

Chronic vs acute SUFE

Answer 16

> 3 weeks = chronic

Question 17

Stable vs unstable SUFE

Answer 17

• Stable (90%) = able to bear weight (good prognosis)

- Unstable (10%) = unable to bear weight (bad prognosis)

Question 18

Investigations for SUFE

Answer 18

• AP radiograph
• Frog-leg lateral radiograph

Of both hips

Question 19

What can delayed diagnosis of SUFE lead to

Answer 19

• Progression of slip w/ increased risk of early OA
• Stable lesions becoming unstable
• AVN of femoral head

Question 20

Rx of SUFE

Answer 20

• Early internal fixation (to stabilise any slippage + encourage physeal closure)
• Prophylactic fixation remains controversial and is assessed on a case by case basis

Question 21

What types of SUFE have low and high risk of AVN

Answer 21

• Stable = Low risk

- Unstable = High risk

Question 22

Why should one have a high index of suspicion for SUFE in 10-16yrs

Answer 22

• Correct age group for SUFE
• Symptoms often mild
• Severe outcomes if missed

Question 23

If a child has symptoms similar to SUFE but is <10yrs/>16yrs what should be considered

Answer 23

-Endocrinopathy e.g. hypothyroidism or growth hormone imbalance

Question 24

Possible outcomes of SUFE

Answer 24

• AVN
• Chondrolysis
• Deformity (short, ext. rotated, limited flexion)
• Early OA
• Limb length discrepancy
• Impingement
• Possibility of slip on other side