Imaging techniques for the evaluation of glenohumeral instability

The ability to image lesions associated with glenohumeral instability has e volved significantly over the past 2 decades. In the past, several imaging techniques ranging from conventional radiography to computerized axial arth rography and, most recently, to magnetic resonance imaging have been used t o depict various labral abnormalities. In most instances, conventional radi ography remains the initial imaging study for evaluating the patient with p ersistent shoulder pain and instability. Recently, however, magnetic resona nce arthrography has been firmly established as the imaging modality of cho ice for demonstrating specific soft tissue abnormalities associated with gl enohumeral instability. This article will review the role of various imagin g modalities including conventional radiography, conventional arthrography, computerized axial arthrography, magnetic resonance imaging, and magnetic resonance arthrography, Emphasis will be placed on the role of magnetic res onance arthrography as it pertains to the lesions associated with glenohume ral instability. A thorough discussion of the appearance of normal anatomic structures, anatomic variations that mimic abnormality, and the various le sions associated with glenohumeral instability will be provided.