What are the guidelines for treating hip dysplasia?

Hip Dysplasia Guidelines

All neonates should undergo clinical hip examination at every well-baby visit, with selective ultrasound screening at 4-6 weeks for high-risk infants (female breech presentation, male breech presentation, positive family history, or abnormal physical examination), and immediate treatment for any confirmed instability or dislocation to prevent early degenerative joint disease. 1, 2

Screening and Diagnosis

Clinical Examination Protocol

Every neonate requires routine physical examination of the hips at well-baby visits (1-2 weeks, 2,4,6,9, and 12 months). 1

• Perform Ortolani and Barlow tests in infants <3 months to detect hip instability—Ortolani tests for already dislocated hips (clunk felt when femoral head slips into acetabulum with abduction), while Barlow tests for dislocatable hips (gentle adduction attempts to dislocate the femoral head posteriorly). 1, 2
• In infants >3 months, assess for limitation of hip abduction and asymmetric thigh folds as these become more reliable clinical signs than instability maneuvers. 1
• In walking children, observe for limping, toe-walking on affected side, increased lumbar lordosis, and waddling gait if bilateral. 1, 3

Important caveat: Normal physical examination does not exclude DDH—imaging is still required for all high-risk infants regardless of examination findings. 1, 2

Risk Factors Requiring Imaging

The American Academy of Pediatrics mandates hip imaging for: 1, 2

• Female infants born in breech presentation (highest risk group)
• Male infants born in breech presentation
• Female infants with positive family history of DDH (optional but recommended)
• Any infant with positive Ortolani or Barlow test
• Inconclusive or equivocal physical examination findings

Additional risk factors include firstborn status, large infant size, and oligohydramnios. 1, 3

Imaging Selection by Age

Age-based imaging algorithm: 1, 2, 4

• <2 weeks: Do not perform ultrasound—physiologic laxity causes high false-positive rates and 60-80% of abnormalities resolve spontaneously. 1, 2
• 2 weeks to 4 months: Ultrasound is the imaging modality of choice—perform at 4-6 weeks for optimal timing. 1, 2, 4
• >4-6 months: Radiography (AP pelvis and frog-leg lateral) becomes preferred—sufficient ossification of femoral head allows reliable radiographic assessment. 1, 2, 4

Universal ultrasound screening is NOT recommended—randomized trials show no significant difference in late DDH detection compared to high-quality serial physical examinations, but universal screening increases overtreatment rates and risk of iatrogenic avascular necrosis. 1, 2

Graf Ultrasound Classification

Treatment decisions based on Graf classification: 1

• Type I (α angle >60°): Normal hip—no treatment or follow-up required
• Type IIa (α angle 50-59°, age <3 months): Immature but normally located—no treatment required, but follow-up advised due to small risk of delayed displacement
• Type IIb, IIc, IId: Require referral for treatment
• Type III (low displacement) and Type IV (high displacement): Require immediate treatment (α angle should be <43°)

Treatment Approach

Immediate Management Based on Findings

Treatment algorithm prioritizing morbidity and mortality: 1, 5

• Ortolani-positive hip (dislocated): Immediate treatment required—do not observe, as untreated dislocation leads to early degenerative joint disease and impaired function. 1, 5
• Barlow-positive hip (dislocatable): Immediate treatment required—same urgency as Ortolani-positive. 2, 5
• Type IIa hip in infant <3 months: Observation with follow-up—84-95% normalize by 3 months without treatment. 2, 5
• Type IIa persisting beyond 3 months (becomes Type IIb): Refer for orthopedic treatment. 1

Age-Specific Treatment Strategies

Treatment varies by age at diagnosis to optimize outcomes: 6, 5, 7

• <6 months: Pavlik harness is first-line treatment—closed reduction successful in 91% of cases up to one year of age. 3, 5
• 6 months to 3 years: Closed or open reduction with spica casting—delayed diagnosis beyond 6 months often requires surgical correction rather than non-invasive treatments. 1, 2, 5
• 3-8 years: Acetabular reshaping osteotomy (Pemberton procedure or San Diego osteotomy) for residual dysplasia. 6
• 8-14 years: Triple innominate osteotomy for residual dysplasia. 6
• >14-15 years (closed triradiate cartilage): Ganz periacetabular osteotomy. 6

Monitoring During Treatment

Serial assessment protocol: 1, 3, 5

• Serial physical examinations and periodic imaging throughout treatment to assess response
• For infants in abduction devices, serial imaging monitors progress
• After successful treatment, transition to radiographic monitoring at 4-6 months of age
• Acetabular index evolution is the best parameter to predict persistent acetabular dysplasia at maturity 5

Critical Pitfalls to Avoid

Avascular necrosis prevention—the most serious complication: 1, 5

• Avoid excessive hip abduction in harness or spica cast—causes femoral head ischemia
• Never force closed reduction when obstacles present—perform open reduction instead
• Do not maintain dislocated hip within harness or cast—confirms reduction before immobilization
• Overtreatment of physiologic immaturity (Type IIa <3 months) causes iatrogenic avascular necrosis 1, 2

Diagnostic pitfalls: 1, 2, 3

• Do not rely solely on physical examination—normal exam does not exclude DDH in high-risk infants
• Do not perform ultrasound before 2 weeks—high false-positive rate from physiologic laxity
• Do not use radiographs for screening before 4 months—largely cartilaginous structures limit reliability
• Do not delay referral beyond 2-4 weeks for confirmed dysplasia—prevents further acetabular underdevelopment 3

Natural History and Prognosis

Untreated DDH outcomes: 1, 3, 5

• DDH is the main cause of total hip replacement in young people (21-29% of cases) due to altered hip biomechanics and early osteoarthritis
• Mild dysplasia may not manifest until adulthood
• Severe dysplasia presents during childhood with functional impairment
• Surgical intervention during childhood or teenage years can alter natural history and greatly improve hip-joint longevity 6