Use of the fulcrum axis improves the accuracy of true anteroposterior radiographs of the shoulder

J Bone Joint Surg Br. 2009 Aug;91(8):1049-53. doi: 10.1302/0301-620X.91B8.22567.


In 100 patients the fulcrum axis which is the line connecting the anterior tip of the coracoid and the posterolateral angle of the acromion, was used to position true anteroposterior radiographs of the shoulder. This method was then compared with the conventional radiological technique in a further 100 patients. Three orthopaedic surgeons counted the number of images without overlap between the humeral head and glenoid and calculated the amount of the glenoid surface visible in each radiograph. The analysis was repeated for intraobserver reliability. The learning curves of both techniques were studied. The amount of free visible glenoid space was significantly higher using the fulcrum-axis method (64 vs 31) and the comparable glenoid size increased significantly (8.56 vs 6.47). Thus the accuracy of the anteroposterior radiographs of the shoulder is impaired by using this technique. The intra and interobserver reliability showed a high consistency. No learning curve was observed for either technique.

Publication types

  • Comparative Study

MeSH terms

  • Acromion / diagnostic imaging*
  • Adult
  • Aged
  • Aged, 80 and over
  • Contusions / complications
  • Contusions / diagnostic imaging*
  • Female
  • Humans
  • Image Interpretation, Computer-Assisted
  • Male
  • Middle Aged
  • Observer Variation
  • Posture
  • Radiography
  • Rotator Cuff / diagnostic imaging*
  • Rotator Cuff Injuries
  • Shoulder Dislocation / diagnostic imaging*
  • Shoulder Fractures / diagnostic imaging*
  • Shoulder Joint / anatomy & histology
  • Shoulder Joint / diagnostic imaging*
  • Young Adult