Current concepts in imaging the adult hip.

Diagnostic imaging plays a key role in the evaluation of adult hip pain. Cornerstone to the initial assessment of hip pain is the plain radiograph. The need for secondary imaging of the hip and choice of imaging modality depends on the clinical presentation, results of the plain radiograph series, and clinical question to be answered. CT is primarily used in acute trauma, particularly in cases of an acetabular fracture or hip dislocation to detect intraarticular fragments and associated articular surface fractures and to better depict fracture patterns for surgical planning. In the setting of normal plain radiographs and unexplained hip pain, MR imaging is particularly helpful in detecting marrow-based abnormalities and demonstrating intra- and extraarticular pathology. MR athrography is useful in the detection of labral injuries and potentially may demonstrate additional intraarticular pathology, including chondral damage, loose bodies, and injuries of the ligamentum teres.