title: Kinematic shoulder MRI: the diagnostic value in acute shoulder dislocations.
abstract: OBJECTIVE
  To determine whether positioning of the arm in adduction and internal rotation would improve the confidence in the diagnosis of Bankart lesions in first time shoulder dislocators.
  
  
  METHODS
  Eleven patients were imaged on an open bore MRI within 1-6 days of traumatic shoulder dislocation with the arm adducted and internally rotated, and subsequently the patients were reimaged with the arm adduced and externally rotated. Two blinded musculoskeletal radiologists determined the confidence of diagnosing labral tears in each of the two positions.
  
  
  RESULTS
  An anterior-inferior labral tear was diagnosed in 11/11 patients in internal rotation and in 6/11 patients in external rotation. The average confidence was 2.8 in internal rotation and 1.5 in external rotation (on a scale of 0-3). Using a Wilcoxon signed rank test, the certainty of the diagnosis was determined to be significantly higher with the arm in internal rotation (P = 0.016).
  
  
  CONCLUSIONS
  MRI performed with the arm in internal rotation for patients with acute first time anterior shoulder dislocation increases the certainty of the diagnosis of anterior-inferior labral tears.
authors.affiliation: Internal Medicine, Johns Hopkins University/Sinai Hospital of Baltimore, Baltimore, MD, USA. MarshallMarcus@gmail.com
authors.forename: Marshall
authors.initials: M
authors.lastname: Marcus
authors.forename: Amit
authors.initials: A
authors.lastname: Malhotra
authors.forename: Moshe
authors.initials: M
authors.lastname: Peri
authors.forename: Mark
authors.initials: M
authors.lastname: Schweitzer
authors.forename: Ougortsin
authors.initials: O
authors.lastname: Vladislav
authors.forename: Shay
authors.initials: S
authors.lastname: Tenebaum
authors.forename: Nogah
authors.initials: N
authors.lastname: Shabshin
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D003937:Diagnosis, Differential; D005260:Female; D050724:Fractures, Cartilage / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D056888:Patient Positioning / Q000379:methods*; D011187:Posture; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012783:Shoulder Dislocation / Q000473:pathology* / Q000503:physiopathology*; D055815:Young Adult