Load & Shift Test
The load and shift test as described by Hawkins is a modification of the anterior and posterior drawer tests of Gerber and Ganz. It has been considered the gold standard for assessment of anterior and posterior instability.
The examiner creates a loading force to relocate the humeral head centrally in the glenoid. In this 'loaded position' directional stresses are applied. The examiner places one hand over the shoulder and scapula to stabilise the shoulder girdle and uses the other hand to grasp the humeral head. The humerus is loaded into the glenoid and then translated anteriorally and posteriorally. As the stress applied is increased the humeral head may be felt to ride up the glenoid rim. This test not only assesses the amount of translation but also provides an idea of the adequacy of the glenoid lip. It is critically important to compare the two shoulders to appreciate similarities or differences in translation.
The test is then repeated in supine. For this position the arm is grasped
and positioned in about 20° of abduction and forward flexion. The humeral head is again loaded then posterior and anterior stresses are applied. Although translation is assessed initially in the neutral position with the arm by the side it is important to assess translations in other positions as well. For example by progressively externally rotating the arm in the normal shoulder in abduction one should appreciate less translation anteriorly as the inferior glenohumeral ligament (GHL) becomes taut and acts as a restraint. Similarly by internally rotating the arm posterior translation is diminished with an intact posterior capsular structure.
|Range of abduction
|0 - 60°
|Superior GHL/Coracohumeralligt/rotator interval
|60 - 90°
Grading system utilised to quantify amount of translation
|1-2 cm or translates to glenoid rim
|>2cm translation or over the rim of the glenoid
According to a research study performed by Hawkins's et al that compared the results of manual examination i.e. the load and shift with results from fluoroscopic assessment the load and shift was oversensitive in diagnosing anterior and posterior instability. This led to the development of the grading system above.
This study also reported that there was no statistically significant difference between results according to the experience of the examiner.
It should be noted that McFarland questions the validity of manual testing procedures in the assessment of instability. He concurs that the load and shift is oversensitive in diagnosing instability.
No known published research regarding specificity and reliability.