What is the management of infant degenerative hip dysplasia through the first five years of life?

Management of Infant Developmental Hip Dysplasia Through the First Five Years of Life

The management of developmental dysplasia of the hip (DDH) in infants follows an age-stratified approach: clinical screening at every well-baby visit, selective ultrasound screening at 4-6 weeks for high-risk infants or abnormal exams, Pavlik harness treatment (most effective before 6 weeks of age) for confirmed instability or dislocation, and transition to radiographic monitoring at 4-6 months with surgical intervention reserved for failed conservative management or late presentations. 1

Screening and Diagnosis Strategy

Birth to 4 Weeks

• No imaging is recommended for infants younger than 4 weeks with equivocal physical examination or risk factors alone 1
• Perform Ortolani and Barlow maneuvers at every well-baby visit (2-4 days, 1 month, 2 months, 4 months, 6 months, 9 months, 12 months) 1, 2
• An Ortolani-positive hip (dislocated but reducible) requires immediate treatment 3
• A Barlow-positive hip (dislocatable but spontaneously reduces) requires close monitoring and imaging at 4-6 weeks 1, 4

4 Weeks to 4 Months

• Ultrasound is the imaging modality of choice for this age group 1, 2
• Perform selective ultrasound screening at 4-6 weeks for: female infants in breech presentation, male infants in breech presentation, positive family history, or abnormal physical examination 4
• The earliest recommended timing is 2 weeks of age, as earlier imaging leads to high false-positive rates from physiologic laxity 4
• 60-90% of borderline abnormal hips identified by ultrasound resolve spontaneously, making observation appropriate for Graf Type IIa hips (immature but normally located) in infants under 3 months 1, 4

4 to 6 Months and Beyond

• Pelvic radiography becomes the preferred imaging modality as the femoral head ossific nucleus appears and sufficient ossification occurs 1
• A normal pelvic radiograph at 4 months reliably excludes DDH in children with risk factors 1
• After 2-3 months of age, limited hip abduction becomes the most important clinical finding as Ortolani and Barlow tests become less sensitive due to capsular tightening 1, 5
• In walking children, assess for limping, toe-walking on the affected side, increased lumbar lordosis, prominent buttocks, and waddling gait if bilateral 2

Treatment Algorithm

Pavlik Harness Treatment (First-Line for Infants Under 6 Months)

• The Pavlik harness is most effective when applied before 6 weeks of age, with overall success rates of 67-83% 1
• Can be used up to 6 months of age, though efficacy decreases with age 1
• Recent long-term data shows excellent outcomes with 96.2% of hips showing no residual dysplasia at 20+ year follow-up when treated with Pavlik harness for Graf type IIc or worse 6
• Use ultrasound to confirm concentric hip reduction and monitor treatment response during harness therapy 1
• Predictors of Pavlik harness failure include: low post-reduction alpha angle, <20% femoral head coverage, bilateral cases, Graf grade IV hips, and younger age at treatment initiation 1, 7

Alternative Bracing Options

• Limited evidence supports the von Rosen splint over Pavlik, Craig, or Frejka splints for initial treatment 1, 2
• The Tübingen hip flexion splint should not be used in severe forms (Graf grade IV) due to significantly higher failure rates (66.6% in bilateral cases) 7

Monitoring During Treatment

• Perform serial physical examinations and periodic ultrasound assessments throughout treatment duration 1, 2
• Radiography is not preferred during harness treatment due to delayed ossific nucleus appearance and suboptimal positioning within the harness 1
• Obtain radiographs at or near conclusion of treatment to document bony acetabular development and provide baseline for future surveillance 1

Surgical Intervention Indications

• Reserved for: severe dysplasia or dislocation, late presentation or diagnosis, or failed nonoperative management 1
• Closed reduction is successful in 91% of cases in infants up to one year of age when concentric reduction without obstacles is achieved 2
• Late presentation is a major negative prognostic factor, with patients more likely to require complex treatment and experience long-term complications 1

Critical Management Principles

Observation vs. Treatment Decision-Making

• Graf Type IIa hips (alpha angle 50-59°) in infants under 3 months require observation only, as 84-95% normalize by 3 months without treatment 4
• If the hip remains immature beyond 3 months (Type IIb), orthopedic referral and possible treatment is indicated 4
• For stable hips with ultrasound abnormalities, observation without bracing may be appropriate 1

Avoiding Avascular Necrosis (Most Serious Complication)

• Avascular necrosis is related to: excessive hip abduction, forced closed reduction when obstacles are present, maintained dislocation within harness or spica cast, and surgical open reduction 3
• Universal ultrasound screening increases detection but carries risk of overtreatment and iatrogenic avascular necrosis without decreasing late diagnosis rates 1
• The risk of overtreatment is why selective screening (not universal) is recommended by the AAP 1, 4

Long-Term Surveillance Through Age 5

Radiographic Monitoring

• The acetabular index is the most commonly used measurement for monitoring acetabular development 2, 5
• The evolution of the acetabular index is the best parameter to predict persistent acetabular dysplasia at maturity 3
• Measure center-edge angle according to Wiberg, Reimers migration percentage (should show ~90% coverage), and Sharp angle 6

Follow-Up Schedule

• Continue hip examinations at all well-child visits through age 5 1, 5
• After successful harness treatment, transition to radiographic monitoring at 4-6 months 4
• Obtain follow-up radiographs at age 1 and 4 years to assess acetabular development 8

Indications for Pelvic or Femoral Osteotomies

• Perform when residual acetabular dysplasia is present or in older children when spontaneous correction after hip reduction is not expected 3
• Acetabular dysplasia improves in the majority due to stimulus from hip reduction, but persistent dysplasia requires surgical correction 3

Common Pitfalls to Avoid

• Do not rely solely on physical examination in high-risk infants, as normal findings do not preclude development of dysplastic hip 2, 4
• Do not perform ultrasound before 2 weeks of age due to high false-positive rates from physiologic hip laxity 4
• Do not use ultrasound after 4-5 months as it overdiagnoses DDH in 40% of patients compared to radiography 1
• Do not overlook referred pain patterns, as hip pathology can present as thigh, knee, or buttock pain 2
• Do not continue Pavlik harness beyond 6 months of age as efficacy significantly decreases 1
• Negative initial radiographs do not completely exclude nondisplaced fractures or subtle dysplasia requiring follow-up 2

Prognostic Considerations

• Unrecognized and untreated DDH inevitably leads to early degenerative joint disease, with DDH causing up to one-third of total hip arthroplasties in patients <60 years of age 1
• Early detection when therapy is noninvasive and most effective is critical for preventing lifelong disability 1, 2
• Long-term outcomes after successful Pavlik harness treatment are excellent, with patients experiencing no significant hip pain limiting activities at 20+ year follow-up 6