Ortho - Developmental Dysplasia of the Hip

Question 1

What is developmental dysplasia of the hip?

Answer 1

Condition where there is structural abnormality in the hips caused by abnormal development of foetal bones in pregnancy

Leads to instability in hips and tendence for subluxation or dislocation

Question 2

What does DDH lead to in adulthood?

Answer 2

Weakness
Recurrent subluxation or dislocation
Abnormal gait
Early degenerative changes

Question 3

When is DDH picked up?

Answer 3

NIPE or later when child presents with hip asymmetry, reduce ROM or limp

Question 4

What are the risk factors for DDH?

Answer 4

• First degree family history
• Breech presentation from 36 weeks onwards
• Breech presentation at birth if 28 weeks onwards
• Multiple pregnancy

Question 5

How is DDH screened for?

Answer 5

NIPE and examination at 6-8 weeks old

Look for
- Different leg lengths
- Reduce hip abduction on one side
- Significant bilateral restriction in abduction
- Difference in knee level when hips flexed
- Clunking of hips on special tests

Question 6

What two tests are used to check for DDH?

Answer 6

Ortolani test
Baby on back with hips and knees flexed

Palms placed on baby’s knees with thumb on inner thigh and fingers on outer thigh

Gentle pressure to abduct hips and apply pressure behind legs to see if hips dislocate

Barlow test
Back on back with hips adducted and flexed at 90 degrees and knees bent at 90 degrees

Gentle downward pressure placed on knees through femur to see if femoral head will dislocate

Question 7

What is a common examination finding when looking for DDH?

Answer 7

Clicking
Soft tissue moves over bone causing a click, does not need an USS but USS will be normal

Clunking more likely to indicate DDH and requires an USS

Question 8

How is DDH diagnosed?

Answer 8

USS of hips is the investigation of choice and can establish diagnosis

All children with risk factors or suggestive findings should have an USS

X-rays useful in older infants

Question 9

How is DDH managed?

Answer 9

Pavlik harness
If baby less than 6 months

Fitted and kept on permanently, adjusting for growth of baby

Holds femoral head in correct position and allows acetabulum to develop normally

Keeps hip in flexed and abducted position

Child reviewed regularly, and removed after 6-8 weeks

Surgery
If harness hails or diagnosis made after 6 months

Hip spica cast used to immobilise hip for prolonged periods of time