Compared to other cross-sectional modalities, ultrasound has several inherent advantages, which also apply to the musculoskeletal system. Among these are ready accessibility, portability, quick scan time, and better patient tolerability. The dynamic, real-time nature of sonography requires personal interaction with the patient, often resulting in a more directed examination, specific for each individual. Scanning technique is easily modified, as needed, to optimize the diagnostic effectiveness of the study. Advances in technology with higher frequency transducers, color/power Doppler capability, and extended field-of-view (FOV) function have facilitated the progressive development of sonography. Newer innovative features such as tissue harmonics and 3-D imaging may prove to be beneficial in the diagnosis of musculoskeletal disorders (1).

As with ultrasound in general, musculoskeletal sonography is highly operator-dependent, and experience and proper training is required to perform consistent, high quality studies. Currently, musculoskeletal ultrasound is offered on a routine basis at only a limited number of facilities in the United States. Most training programs do not perform a significant number of musculoskeletal ultrasound examinations, therefore do not include this modality as part of their curriculum.

Outside the United States, and in particular Europe, musculoskeletal sonography is often the primary modality performed for many clinical indications. Because of the wide availability of magnetic resonance imaging, arthrosonography has been relatively underutilized in the United States. Additionally, physicians, including radiologist, are often times unaware of the potential applications of sonography for the assessment of joint and soft tissue disease. As cost constraints continue to influence patient management decisions, musculoskeletal ultrasound may become the preferred method for imaging evaluation over more expensive studies (1).

In this tutorial, general principles and proper technique in musculoskeletal sonography are demonstrated. Normal anatomy, presented in static and real-time video clips, is shown. We illustrate a broad spectrum of pathologic conditions of the musculoskeletal system that are commonly diagnosed with sonography. Interventional procedures using ultrasound guidance such as joint aspirations and soft tissue biopsies are also shown. Our goal is to give a thorough illustration of the potential applications of sonography in the musculoskeletal system. And in the process, it is our hope to inspire radiologists to consider musculoskeletal sonography as a viable, and frequently primary, option in the assessment of joint and soft tissue disorders.