title: Imaging findings in posterior instability of the shoulder.
abstract: Posterior shoulder instability refers to the symptoms and signs resulting from excessive posterior translation of the humerus. Magnetic resonance (MR) imaging is the radiological modality of choice in the diagnostic assessment of posterior instability. Computed tomography (CT) is useful in the evaluation of osseous abnormalities associated with posterior instability. A detailed description of the posterior osseous and labroligamentous abnormalities has evolved recently, and many variant lesions of the posteroinferior labrum and/or capsular structures have been described. As the recommended surgical management of lesions associated with posterior instability is a lesion-specific approach, awareness of the specific lesions that have been described in association with posterior instability helps in pre-surgical planning. The purpose of this article is to review the classification of, and injury mechanisms leading to, posterior shoulder instability and to describe imaging findings associated with posterior instability, with emphasis on MR imaging.
authors.affiliation: Department of Diagnostic Imaging, St. Joseph's Healthcare, Hamilton, ON, L8N 4A6, Canada. sriniharish@gmail.com
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Harish
authors.forename: Arpit
authors.initials: A
authors.lastname: Nagar
authors.forename: Jaydeep
authors.initials: J
authors.lastname: Moro
authors.forename: David
authors.initials: D
authors.lastname: Pugh
authors.forename: Ryan
authors.initials: R
authors.lastname: Rebello
authors.forename: John
authors.initials: J
authors.lastname: O'Neill
mesh_terms: D006801:Humans; D007593:Joint Instability / Q000175:diagnosis* / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D000070599:Shoulder Injuries; D012785:Shoulder Joint / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed / Q000379:methods*