Shoulder Dislocation Surgery Workup

Updated: Feb 13, 2019
  • Author: Scott Welsh, MD; Chief Editor: S Ashfaq Hasan, MD  more...
  • Print
Workup

Imaging Studies

Radiography

Conventional radiography should be performed in all patients with suspected shoulder dislocations to confirm the diagnosis and also to exclude associated fractures prior to any attempted reduction. [14] Routine radiographs should include at least an anteroposterior (AP) view and an axillary view. [15]

The AP view can be obtained in neutral, internal, or external rotation. In internal rotation, one can easily see a Hill-Sachs lesion of the posterolateral humeral head.

The axillary view nicely shows glenohumeral subluxation or dislocation, as well as anterior or posterior glenoid rim fractures. [16] A standard axillary view may be difficult in the acute injury setting because it requires 90° of abduction. However, many modifications exist to avoid excessive movement of the painful extremity. For example, the transverse axillary lateral requires the patient to abduct the arm only 10-30°.

Other views that may be useful include the scapular Y view, which is helpful for diagnosing dislocations and scapular fractures. This view, however, should not replace the axillary view, because it does not show subtle subluxations of the glenohumeral joint or fractures of the glenoid rim.

The true AP or Grashey view is helpful in assessing subtle joint incongruity, superior or inferior subluxation, degenerative changes, or glenoid hypoplasia.

The Garth or West Point view is useful in detecting bony Bankart fractures of the anteroinferior glenoid rim as well as Hill-Sachs defects. This view is advantageous in the acute setting because it does not necessitate the patient moving the arm.

The Stryker notch view can also be useful in detecting Hill-Sachs lesions. However, this view is of limited usefulness in detecting subluxations or glenoid fractures.

CT arthrography, MRI, and MR arthrography

Computed tomography (CT) arthrography, magnetic resonance imaging (MRI), or magnetic resonance arthrography may be helpful in assessing some shoulder dislocations. [17]

CT arthrography was commonly used in the past to evaluate patients with glenohumeral instability either after the initial dislocation or with recurrent instability. Currently, it is used only if MRI is contraindicated or if glenoid version abnormalities are suspected. Multidetector CT (MDCT) with three-dimensional (3D) volume rendering can be helpful in further characterization of osseous abnormalities. [18]

MRI and magnetic resonance (MR) arthrography have been shown to be more sensitive than other methods in detecting labral and ligamentous pathology, rotator cuff and cartilage tears, capsular abnormalities, and biceps injuries. MR arthrography is more sensitive than MRI alone and is the study of choice after a shoulder dislocation, particularly in cases of recurrent instability. In addition, it is superior to MRI for diagnosing the pathologic lesions mentioned above.