Pediatric musculoskeletal ultrasound: a pictorial essay.

Ultrasound (US) is the main imaging modality for the evaluation of pediatric patients with musculoskeletal diseases; particularly, it is an appropriate and reliable tool for diagnosis, follow-up and treatment of several musculoskeletal pathologies affecting the pediatric age. High-frequency (10-15 MHz) and high-resolution probes provide very lofty quality images, allowing a detailed study of the pediatric musculoskeletal system. Among the well-known advantages of this technique-such as the absence of ionizing radiations, its low cost and wide availability-US can as well rely on some intrinsic characteristics of the pediatric musculoskeletal system that can improve its diagnostic capability. The unossified portions of the pediatric skeleton and the absence of a thickened adipose tissue allow US to be highly effective and reliable in the study of muscles, tendons and cartilage. Lower-frequency sectoral transducers can be required in the study of some joints such as the shoulder or the hip, as well as in the examination of deep soft-tissue lesions. Furthermore, both color and spectral Doppler play an important role in the examination of soft-tissue lesions and synovial phlogosis. In this pictorial essay the main pathological conditions of pediatric musculoskeletal system will be examined, such as painful hip, evolutionary hip dysplasia, osteochondrosis, trauma-related pathologies and juvenile idiopathic arthritis.