What are the diagnostic and treatment approaches for hip pathology in the pediatric age group?

Diagnostic and Treatment Approaches for Hip Pathology in the Pediatric Age Group

Initial imaging should be age-appropriate, with ultrasound for infants under 4 months and radiographs for older children, to accurately diagnose hip pathologies and guide appropriate treatment. 1, 2

Common Hip Pathologies in Children

Developmental Dysplasia of the Hip (DDH)

• Affects 1.5 in 1,000 of American Caucasian population, 4-8 times more common in females 2
• Risk factors include family history, firstborn status, large infant size, oligohydramnios, and breech presentation 2
• 60-80% of abnormalities identified on physical examination and >90% identified on ultrasound resolve spontaneously 2
• Untreated subluxed and dislocated hips can lead to early degenerative joint disease and impaired function 2

Diagnostic Approach for DDH

• Clinical examination should be performed at each well-baby visit 2
• For infants <3 months: Ortolani and Barlow tests are most useful 2
• For children >3 months: Limitation of hip abduction and asymmetric thigh folds are more useful clinical signs 2
• In walking children: Look for typical limp, toe-walking on affected side, increased lumbar lordosis, prominent buttocks, and waddling gait if bilateral 2

Imaging for DDH

• Ultrasound is the imaging modality of choice for infants younger than 4 months 1, 3
• Radiographs become more reliable by 4-6 months of age when sufficient ossification has occurred 1, 2
• Selective ultrasound screening recommended at 4-6 weeks for high-risk infants 1
• Earliest recommended timing for ultrasound is 2 weeks of age, as hip instability often resolves spontaneously by this time 1

Treatment for DDH

• Limited evidence supports use of the von Rosen splint over Pavlik, Craig, or Frejka splints during initial hip instability treatment 2
• Serial physical examinations and periodic imaging assessments are recommended throughout treatment 2
• For stable hips with ultrasound abnormalities, observation without bracing may be appropriate 2

Acute Limping Child

Diagnostic Approach

• Initial evaluation with limited tibial/fibula radiographs is suggested for walking children with nonlocalized limp 2
• If initial imaging is normal but symptoms persist, follow-up radiographs or radiographs of other areas may be useful 2
• MRI is highly sensitive for detecting soft-tissue, cartilage, and bony pathology, including stress reactions/fractures 2
• Ultrasound has limited field of view but is useful for evaluating joint effusions and soft-tissue fluid collections 2

Common Causes of Acute Limp

• Spiral tibial fractures are the most common fractures in children <4 years presenting with nonlocalized limp 2
• Other causes include osteochondritis, apophysitis, osteonecrosis, and tumors 2
• Toddler's fracture (nondisplaced oblique distal tibial fracture) may go unrecognized on initial radiographs 2

Other Significant Hip Pathologies

Legg-Calvé-Perthes Disease and Slipped Capital Femoral Epiphysis

• These are common pediatric hip disorders requiring careful evaluation 4
• MRI is superior to both ultrasound and radiography in detecting inflammatory changes, early erosions, and cartilage thinning 2
• If left untreated, these conditions may lead to significant impairment requiring total hip arthroplasty in adolescence or adulthood 5

Hip Infection Concerns

• When hip infection is suspected, urgent evaluation is necessary 2
• Bone scan is reported to have high sensitivity for diagnosis of osteomyelitis 2
• MRI should be performed when a tumor is suspected as it is sensitive for evaluation of bone marrow and soft-tissue extension 2

Monitoring and Follow-up

• For infants undergoing treatment with abduction devices, serial imaging is recommended to monitor progress 1
• After successful treatment, transition to radiographic monitoring typically occurs at 4-6 months of age 1
• If initial evaluation is negative and symptoms persist or worsen, follow-up clinical reassessment and further imaging evaluation may be necessary 2

Common Pitfalls and Caveats

• Negative radiographs do not completely exclude the possibility of a nondisplaced fracture 2
• Ultrasound has high sensitivity but can lead to overdiagnosis and overtreatment if performed too early (before 2 weeks of age) 1
• Pain due to hip pathology can be referred elsewhere in the lower extremity (thigh, knee, buttock), leading to misdiagnosis 2
• Normal results on physical examination do not preclude the development of a dysplastic hip in an infant 2