Shoulder (modified trauma axial view)

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The modified trauma axial view is a supplementary projection that replaces the ‘Y view’ of the two-view shoulder series. It is an orthogonal view of the AP projection of the glenohumeral joint and is often performed in the context of trauma.

Indications

The modified trauma axial view is used to assess the articulations of the shoulder and the relationship of the humeral head with the glenoid. It is an optimal projection for possible scapulohumeral dislocations, glenoid fractures and Hill-Sachs lesions , with a higher diagnostic yield than the lateral scapular shoulder view.

Patient position

  • the patient is supine or seated
  • affected arm is placed beside the patient, if possible externally rotate
  • the detector is placed under the patient running parallel to the thorax

Technical factors

  • axial projection
  • centering point: glenohumeral joint with a 45° caudal angle
  • collimation
    • superior to the skin margins
    • inferior to include one-third of the proximal humerus
    • lateral to include the skin margin
    • medial to include the distal third of the clavicle
  • orientation: portrait 
  • detector size: 18 cm x 24 cm
  • exposure
    • 60-70 kVp
    • 10-17 mAs
  • SID: 100-150 cm
  • grid: no

Image technical evaluation

Slightly magnified (due to subject field distance).

Clear visualization of the humeral head (with little to no superimposition) and its relationship with the glenoid of the scapula, in addition to the acromion and coracoid process

Practical points

This projection has been proven to be as diagnostically relevant as the lateral ‘Y’ view in trauma . Studies have shown that if it replaced the ‘Y’ view, no abnormalities would be overlooked.

In trauma, this projection can be utilized on the supine patient with little to no effort on the patient's behalf, although it can get tricky with the subject-to-film distance and magnification.

Remember to adjust your exposure in accordance with your angle; a steeper angle means the x-ray needs to penetrate through more tissue.

The humeral head will be displaced superior to the glenoid if it is a posterior dislocation and inferior if it is anterior.