Technical and Interpretive Pitfalls in Pediatric Musculoskeletal Ultrasound

The use of musculoskeletal (MSK) ultrasound (US) in pediatric rheumatology has expanded rapidly with various diagnostic and therapeutic indications. Unlike magnetic resonance imaging (MRI), US allows real-time dynamic assessment, evaluation of multiple joints in a single session and comparison with contralateral limb. However, a long learning curve and lack of experience with MSK US in pediatric patients still precludes its routine use at many imaging centers. It is prudent for pediatric radiologists to be aware of normal US appearances of the growing MSK structures to avoid their misinterpretation as pathology. The normal MSK US findings in children which can be confused with pathology and create diagnostic difficulty can arise due to variable states of maturation of bones, cartilage and tendons, complex anatomical locations, accessory structures, and artifacts. Herein, we describe the various technical and interpretive challenges encountered with MSK US in pediatric patients.