title: [Clinical or radiological diagnosis of impingement].
abstract: OBJECTIVE
  Shoulder impingement syndrome is a clinically common entity involving trapping of tendons or bursa with typical clinical findings.
  
  
  METHODS
  Important radiological procedures are ultrasound, magnetic resonance imaging (MRI) and MR arthrography. Projection radiography and computed tomography (CT) are ideal to identify bony changes and CT arthrography also serves as an alternative method in cases of contraindications for MRI. These modalities support the clinically suspected diagnosis of impingement syndrome and may identify its cause in primary diagnosis. In addition, effects of impingement are determined by imaging. Therapy decisions are based on a synopsis of radiological and clinical findings.
  
  
  METHODS
  The sensitivity and specificity of these imaging modalities with regard to the diagnostics of a clinically evident impingement syndrome are given in this review article.
  
  
  CONCLUSIONS
  Orthopedic and trauma surgeons express the suspicion of an impingement syndrome based on patient history and physical examination and radiologists confirm structural changes and damage of intra-articular structures using dedicated imaging techniques.
authors.affiliation: Klinik für diagnostische und interventionelle Radiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Deutschland, jost.kloth@med.uni-heidelberg.de.
authors.forename: J K
authors.initials: JK
authors.lastname: Kloth
authors.forename: F
authors.initials: F
authors.lastname: Zeifang
authors.forename: M-A
authors.initials: MA
authors.lastname: Weber
mesh_terms: D001175:Arthrography / Q000379:methods*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D018579:Patient Selection; D010808:Physical Examination / Q000379:methods*; D011300:Preoperative Care / Q000379:methods; D019534:Shoulder Impingement Syndrome / Q000175:diagnosis* / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods*