For a 4-week-old with positive Barlow and Ortolani tests, which study best confirms the diagnosis?

For a 4-week-old with positive Barlow and Ortolani tests, which study best confirms the diagnosis?

• A. Ultrasound
• B. Arthrography
• C. MRI
• D. Plain film radiograph

Answer: (A)

In a 4-week-old with positive Barlow and Ortolani tests, you’re dealing with suspected developmental dysplasia of the hip. At this age the femoral head and acetabulum are largely cartilage, so plain X-rays don’t show the joint reliably. Ultrasound can visualize the cartilaginous structures and assess stability dynamically, allowing accurate confirmation of hip dislocation or subluxation and guiding early treatment. MRI is less practical for newborns and often requires sedation; arthrography is invasive and not a first-line test in this age group; plain radiographs are not informative yet due to lack of ossification. Therefore, ultrasound is the best study to confirm the diagnosis in a 4-week-old.

In a 4-week-old with positive Barlow and Ortolani tests, you’re dealing with suspected developmental dysplasia of the hip. At this age the femoral head and acetabulum are largely cartilage, so plain X-rays don’t show the joint reliably. Ultrasound can visualize the cartilaginous structures and assess stability dynamically, allowing accurate confirmation of hip dislocation or subluxation and guiding early treatment. MRI is less practical for newborns and often requires sedation; arthrography is invasive and not a first-line test in this age group; plain radiographs are not informative yet due to lack of ossification. Therefore, ultrasound is the best study to confirm the diagnosis in a 4-week-old.