LOAD AND SHIFT TEST TO ASSESS ANTERIOR AND POSTERIOR SHOULDER INSTABILITY The Load and Shift Test can be used to assess anterior as well as posterior shoulder instability. With instability on either side, you will feel increased translation of the humeral head compared to the unaffected side. A translation of up to 25% of the humeral head's diameter is considered normally anteriorly and a translation up to 50% of the diameter is considered normal for the posterior translation. The test is consid