title: Shoulder impingement syndromes.
abstract: OBJECTIVE
  Not all shoulder pain conditions are a consequence of rotator cuff injuries secondary to anterior subacromial impingement. Additional causative forms have been identified and classified as posterosuperior glenoid rim, subcoracoid and suprascapular nerve (at spinoglenoid notch) impingement syndromes.
  
  
  METHODS
  We reviewed 206 consecutive magnetic resonance examinations carried out with conventional T1- and T2-weighted spin-echo and gradient-echo sequences in patients complaining of shoulder pain. Adjunctive sequences were acquired with the involved arm positioned in abduction and external rotation.
  
  
  RESULTS
  Anterior subacromial impingement is only one of the possible causes of shoulder disorders. Posterosuperior glenoid rim impingement is the most frequent cause of shoulder pain in young throwers. Subcoracoid and spinoglenoid notch suprascapular nerve impingement are additional forms that must be considered in the differential diagnosis because of their frequent occurrence in routine clinical practice.
  
  
  CONCLUSIONS
  Magnetic resonance imaging is the most useful diagnostic modality for shoulder disorders.
authors.affiliation: Italian Olympic Committee Sports Science Institute, Rome.
authors.forename: F
authors.initials: F
authors.lastname: Rossi
mesh_terms: D018450:Disease Progression; D006801:Humans; D008279:Magnetic Resonance Imaging; D009133:Muscular Atrophy / Q000145:classification / Q000175:diagnosis; D016059:Range of Motion, Articular / Q000502:physiology; D019534:Shoulder Impingement Syndrome / Q000145:classification / Q000175:diagnosis*; D012785:Shoulder Joint / Q000473:pathology