title: Rotator cuff strain: a post-traumatic mimicker of tendonitis on MRI.
abstract: OBJECTIVE
  To determine whether there is a subset of young patients (< 35 years) with acute, post-traumatic insults to the rotator cuff which mimic the early stages of impingement.
  
  
  METHODS
  One hundred and ninety-seven consecutive shoulder MR images were retrospectively reviewed, and the results of 83 clinically correlated. Two observers independently evaluated the location of intra-tendon signal and adjacent bone marrow abnormalities on T1- and T2-weighted images. These findings were correlated with age, history of trauma, and surgical or clinical follow-ups.
  
  
  RESULTS
  Patients younger than 35 years had signal intensity that was more localized in atypical locations (posterior aspect of the supraspinatus tendon), more commonly associated with marrow abnormalities (presumed bone bruise), and more often associated with trauma. Younger patients also were less likely to require surgery, especially if they showed bone bruises. This differentiated them from older patients (> 45 years), who demonstrated more widespread signal within the tendon, rare bone bruises, and more frequent surgery.
  
  
  CONCLUSIONS
  Localized tendon signal in atypical locations of the supraspinatus tendon, particularly when associated with bone bruise and young age, suggests the possibility of a post-traumatic strain.
authors.affiliation: Department of Radiology, Thomas Jefferson University Hospital, Philadelphia, PA 19107, USA.
authors.forename: K F
authors.initials: KF
authors.lastname: Anzilotti
authors.forename: M E
authors.initials: ME
authors.lastname: Schweitzer
authors.forename: M
authors.initials: M
authors.lastname: Oliveri
authors.forename: P J
authors.initials: PJ
authors.lastname: Marone
mesh_terms: D000328:Adult; D000367:Age Factors; D001853:Bone Marrow / Q000473:pathology; D016022:Case-Control Studies; D003288:Contusions / Q000175:diagnosis; D012090:Cumulative Trauma Disorders / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D017006:Rotator Cuff / Q000473:pathology; D000070636:Rotator Cuff Injuries; D019534:Shoulder Impingement Syndrome / Q000175:diagnosis*; D052256:Tendinopathy / Q000175:diagnosis*