title: Clinical impact of MR arthrography of the shoulder.
abstract: OBJECTIVE
  To evaluate the effect of MR arthrography of the shoulder on diagnostic thinking and therapeutic decisions by orthopedic shoulder surgeons.
  
  
  METHODS
  Orthopedic surgeons completed a questionnaire before and after MR arthrography for 73 consecutive patients. The main indications were suspected rotator cuff abnormalities. The clinical diagnosis, the degree of confidence in this diagnosis, and the therapeutic decision were noted before and after MR imaging. Surgical reports were available for 34 patients.
  
  
  RESULTS
  Thirty-four percent of the pre-MR imaging diagnoses were withdrawn after MR imaging, and new diagnoses were made after MR imaging in 13% of the cases. Confidence in the diagnosis increased significantly after MR imaging for supraspinatus and infraspinatus lesions (p<0.05). Changes of therapeutic decision after MR imaging were noted in 36 of the 73 patients (49%). In 23 patients, more invasive therapeutic procedures were initiated after MR imaging, and a more conservative treatment was implemented for 13 patients. Agreement of MR diagnoses with surgery was 94% for supraspinatus tears, 87% for infraspinatus tears, 77% for subscapularis tears, and 81% for biceps tendon lesions. Agreement of clinical diagnoses with surgery was 56%, 83%, 50%, and 64%, respectively.
  
  
  CONCLUSIONS
  MR arthrography of the shoulder has a major effect on diagnostic thinking and therapeutic decisions by orthopedic shoulder surgeons.
authors.affiliation: Department of Radiology, Orthopedic University Clinic Balgrist, Zurich, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Zanetti
authors.forename: B
authors.initials: B
authors.lastname: Jost
authors.forename: A
authors.initials: A
authors.lastname: Lustenberger
authors.forename: J
authors.initials: J
authors.lastname: Hodler
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007592:Joint Diseases / Q000175:diagnosis / Q000628:therapy; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D000070599:Shoulder Injuries; D012785:Shoulder Joint / Q000473:pathology*