External Rotation Lag Sign (ERLS)
Pt is seated and elbow passively flexed to 90 while shoulder is held at 20 degrees of elevation in the scapular plane in a position of near maximum external rotation minus about 5 degrees.
If able to hold = negative test
If unable to hold, arm may spring back anteriorly = indicates teres minor/infraspinatus/supraspinatus are weak or painful
Citation
For attribution, please cite this work as:
Yomogida N, Kerstein C. External Rotation Lag
Sign (ERLS). https://yomokerst.com/The
Archive/Examination/Tests and Measures/Upper Extremity Tests/Shoulder
Tests/ERLS_external_rotation_lag_sign_test.html