Imaging of stress injuries of the pelvis.

Stress fractures are common, representing the final stage in a continuum of bone response to continued mechanical damage. Encompassing fatigue- and insufficiency-type fractures, stress fractures of the pelvis are likely underreported. Radiographs are insensitive to stress injuries, particularly those in the pelvis, whereas scintigraphy and magnetic resonance imaging are exquisitely sensitive. In this article we discuss the pathophysiology and imaging appearances of stress injuries of the pelvis and sacrum. Relevant literature regarding risk factors, problem-solving issues, and an imaging algorithm are discussed, with the goal of improving accuracy in the diagnosis of these common injuries.