Shoulder 90/90 External Rotation Assessment (Golf)

The purpose of the shoulder 90/90 assessment is to look at the golfer's shoulder ROM in both neutral spine and a slightly flexed spine, that is consistent with the golfer's starting position (The Address Position).  During the takeaway phase of the golf swing, the golfer should have approximately 66 degrees of ER on the trailing shoulder (Zheng, 2007).  It is important that when evaluating a golfer for shoulder pain/injury that you look at external rotation in the athletic/starting position in addition to a neutral position.  If you see a significant change then it will give you an indication of what to look for next (Ex: poor thoracic mobility).