Do all breech presentations at delivery require hip ultrasound at 6 weeks for developmental dysplasia of the hip (DDH) screening?

Hip Ultrasound Screening for Breech Presentations

All infants with breech presentation should undergo hip ultrasound screening at 6 weeks of age, followed by radiographic evaluation at 4-6 months, as the risk of subsequent dysplasia is too high to discharge patients after a normal ultrasound. 1, 2

Risk Factors for Developmental Dysplasia of the Hip (DDH)

Breech positioning is one of the most significant risk factors for DDH:

• Carries a 3.8 times increased risk compared to normal positioning 1
• Causes extreme hip flexion with knee extension, leading to shortening and contracture of the iliopsoas muscle, promoting femoral head dislocation 1
• Is considered the most important risk factor for hip dysplasia 2

Other notable risk factors include:

• Female gender (2.5 times higher risk than males) 1
• Positive family history (1.4 times increased risk) 1
• Left hip (three times more frequently affected) 1

Screening Protocol for Breech Presentations

Initial Assessment

• All infants should undergo clinical examination at birth and at every well-baby visit until 12 months of age 1
• Clinical examination should include Ortolani test, Barlow test, and assessment of hip abduction 1

Ultrasound Screening

• Ultrasound is the preferred imaging modality for infants between 4 weeks and 4 months 1
• Recommended timing: 6 weeks of age 1, 2
• Important: A normal ultrasound at 6 weeks does not rule out later development of DDH 2, 3

Follow-up Radiographic Evaluation

• An anteroposterior (AP) pelvis and frog lateral radiograph at 4-6 months is essential 2
• Research shows that 29% of breech infants with normal ultrasounds at 6 weeks were found to have dysplasia requiring treatment at 4-6 months follow-up 2

Evidence-Based Considerations

Gender Differences

• Female breech infants have a significantly higher risk of DDH compared to males (12.50% vs 3.23% in those with negative physical exams) 4
• The American Academy of Pediatrics recommends ultrasound screening for all breech females, while making it optional for breech males 5

Prematurity Considerations

• Recent evidence suggests that screening ultrasounds can be performed at 5-8 weeks of unadjusted age without adjusting for prematurity 6
• No significant difference in alpha angle or femoral head coverage between premature and full-term patients at this age 6

Mode of Delivery

• No significant difference in DDH rates based on mode of delivery (cesarean section vs vaginal) 4

Clinical Pitfalls to Avoid

1. Relying solely on physical examination: Up to 29% of breech infants with normal clinical exams and normal ultrasounds at 6 weeks may develop dysplasia requiring treatment 2

2. Discharging after a normal ultrasound: Cases of late-presenting DDH have been reported in infants with previously normal hip exams and normal ultrasounds at 6 weeks 3

3. Inadequate follow-up: The American College of Radiology recommends continued monitoring through skeletal maturity, as complications can develop during growth spurts 1

4. Missing the treatment window: Pavlik harness treatment is most effective when applied before 6 weeks, with success rates of 70-95% 1

Treatment Considerations

If DDH is detected:

• Pavlik harness is the first-line treatment (success rate 70-95% when applied before 6 weeks) 1
• Treatment duration typically 6-12 weeks 1
• If Pavlik harness fails, closed reduction with hip spica cast may be necessary 1
• Surgical intervention may be required for older children or those with irreducible hips 1

Remember that untreated DDH can lead to premature osteoarthritis and may cause up to one-third of all total hip arthroplasties in patients under 60 years 1.