At what age should screening for Developmental Dysplasia of the Hip (DDH) occur?

Screening for Developmental Dysplasia of the Hip (DDH)

Screening for DDH should occur with clinical examination at birth, at 2-4 weeks, and at each well-baby visit through 12 months of age, with selective ultrasound screening at 4-6 weeks for high-risk infants and radiography after 4 months of age when ossification centers develop. 1

Clinical Screening Timeline

• Newborn period: Initial clinical examination at birth
• 2-4 weeks of age: Follow-up clinical examination
• 2,4,6,9, and 12 months: Continued examination at all well-baby visits 1

Risk-Based Imaging Recommendations

High-Risk Infants (requiring selective ultrasound):

• Girls with breech presentation
• Girls with positive family history
• Boys with breech presentation
• Infants with inconclusive physical examination 1

Timing of Imaging:

• Ultrasound:

  • Optimal timing: 4-6 weeks of age 1
  • Should not be performed before 2 weeks of age due to physiologic laxity 1
  • Not recommended during immediate newborn period due to high false-positive rates 1

• Radiography:

  • Optimal timing: After 4 months of age 1
  • Becomes preferred confirmatory imaging once ossific nucleus appears (typically 4-6 months)
  • Limited utility before 3 months due to cartilaginous acetabular margin 1

Clinical Examination Techniques

• Barlow test: Assesses if a reduced hip can be dislocated
• Ortolani test: Assesses if a dislocated hip can be reduced
• Limited hip abduction: Most important screening method after 8-12 weeks when capsule laxity decreases 1
• Other signs: Asymmetric skin folds, limb shortening (less specific) 1

Rationale for Timing Recommendations

1. Early newborn period (0-2 weeks):

   • High false-positive rates due to physiologic laxity
   • 60-80% of abnormalities on physical exam and >90% on ultrasound resolve spontaneously 1

2. 4-6 weeks for ultrasound:

   • Allows time for normalization of neonatal physiologic laxity
   • Balances early detection with avoiding overdiagnosis
   • In a study of 5,170 infants, 84-95% of Graf type II hips normalized by 3 months 1

3. After 4 months for radiography:

   • Coincides with ossification of femoral head
   • Allows assessment of acetabular morphology and femoral head position
   • Normal radiograph at 4 months can reliably exclude DDH in children with risk factors 1

Common Pitfalls and Caveats

• Overdiagnosis risk: Ultrasound in the immediate newborn period can lead to unnecessary treatment due to detection of physiologic laxity 1
• Missed diagnosis risk: Late-presenting DDH (after 3 months) occurs at a rate of 0.22 per 1,000 births 1
• Changing examination findings: After 8-12 weeks, Barlow and Ortolani tests may become negative even with DDH as capsule laxity decreases 1
• Imaging limitations:
  • Ultrasound overdiagnosed DDH in 40% of patients aged 4-6 months compared to radiographs 1
  • Radiographs have limited utility before ossification centers appear 1

Early diagnosis and treatment significantly reduce morbidity and improve outcomes by allowing for non-surgical management with devices like the Pavlik harness, avoiding more invasive interventions required for late diagnoses 2, 3.