COMPARATIVE ANALYSIS OF ULTRASOUND AND RADIOGRAPHY IN THE DIAGNOSIS OF CONGENITAL HIP DISLOCATION AND DYSPLASIA IN CHILDREN

Developmental dysplasia of the hip (DDH) encompasses a spectrum of disorders affecting the femoroacetabular joint, ranging from mild acetabular dysplasia to complete hip dislocation. Early and accurate diagnosis is paramount for optimizing treatment outcomes and preventing long-term morbidity. This article provides a comprehensive comparative analysis of ultrasound (US) and radiographic imaging modalities in the diagnosis of congenital hip dislocation and dysplasia in the pediatric population. Objective: To evaluate the diagnostic performance, advantages, limitations, and optimal clinical applications of ultrasonography versus radiography in the assessment of DDH across different age groups. Methods: A systematic review of the literature was conducted, synthesizing evidence from studies comparing ultrasound and radiographic techniques for DDH diagnosis. Results: Ultrasound demonstrates superior sensitivity (approximately 36-57% for clinical examination versus US reference standard) and is the modality of choice for infants under 4-6 months of age due to its ability to visualize non-ossified femoral heads and provide dynamic assessment without ionizing radiation. Radiography becomes the preferred modality after femoral head ossification (beyond 4-6 months), offering standardized measurements including the acetabular index, Hilgenreiner line, Perkins line, and Shenton line, with Tönnis and International Hip Dysplasia Institute (IHDI) classification systems guiding severity assessment. Advanced imaging techniques including contrast-enhanced ultrasound, three-dimensional ultrasound, and artificial intelligence-assisted diagnostics are emerging as valuable adjuncts. Conclusion: The selection between ultrasound and radiography for DDH diagnosis is age-dependent and context-specific. Ultrasound serves as the primary screening and diagnostic tool in young infants, while radiography assumes primacy in older children. Understanding the complementary roles of these modalities is essential for optimizing diagnostic accuracy and minimizing unnecessary radiation exposure in the pediatric population.