Ultrasound (US) is a simple, non-invasive imaging modality which allows high-resolution imaging of the musculoskeletal (MSK) system. Its increasing popularity in pediatrics is due to the fact that it does not involve radiation, has an ability to visualize non-ossified cartilaginous and vascular structures, allows dynamic imaging and quick contralateral comparison. US is the primary imaging modality in some pediatric MSK conditions like infant hip in developmental dysplasia (DDH), hip joint effusion, epiphyseal trauma and evaluation of the neonatal spine. US is the modality of choice in infants with DDH, both in the initial evaluation and post-treatment follow-up. US has a sensitivity equivalent to MRI in evaluation of the neonatal spine in experienced hands and is a good screening modality in neonates with suspected occult neural tube defects. In other MSK applications, it is often used for the initial diagnosis or in addition to other imaging modalities. In trauma and infections, US can often detect early and subtle soft tissue abnormalities and a quick comparison with the contralateral side aids in diagnoses. Dynamic imaging is crucial in evaluating congenital instabilities and dislocations, soft tissue and ligamentous injuries, epiphyseal injuries and fracture separations. High-resolution imaging along with color Doppler (CD) is useful in the characterization of soft tissue masses. This article reviews the applications of US in pediatric MSK with emphasis on conditions where it is a primary modality. Limitations of US include inability to penetrate bone, hence, limited diagnosis of intraosseous pathology and operator dependency.
Keywords: Developmental dysplasia of the hip (DDH); Epiphyseal injuries; Neonatal spine; Pediatric musculoskeletal ultrasound.