Pitfalls in Musculoskeletal Ultrasound

Abstract

Pitfalls are generally acknowledged as difficulties or traps. They are frequently altering the process of medical diagnosis, especially when imaging procedures are involved. Ultrasonography is the most “operator dependent” among imaging procedures. The result of an ultrasound examination is mainly an image interpretation. Pitfalls may significantly alter both the acquisition and the interpretation of ultrasound images.

Artifacts are responsible for most of the acquisition pitfalls, leading to both false-positive and false-negative conclusions. They are in fact artificially created echoes, without a real correspondent in the examined tissue. This chapter addresses specific ultrasound artifacts. Some of them like anisotropy, attenuation, or enhancement through transmission are encountered in almost every ultrasound examination. Others are more uncommon, but increasing their awareness is also mandatory for accurately performing the procedure. Artifacts are pitfalls specifically connected to the technical part of ultrasonography and are consequences of physics principles applied to the human body.

Apart from artifacts, ultrasound examination may be altered by improper use/damage of the ultrasound machine involved in the investigation or by human errors: of the performing practitioner or of the examined patients. Pitfalls may also be generated by anatomical variants, often misleading during diagnosis process. New areas of musculoskeletal ultrasound application such as children pathology or thoracic evaluation could be sources of pitfalls for an unexperienced practitioner. The chapter contains a short description of the most important pitfalls of musculoskeletal ultrasound evaluation and, more important, useful tips to surmount them when possible.