Resetting a Frozen Shoulder?

In this 25+ min video, I evaluate and treat a physio from South America. After injury or surgery (or both - it's been several years), he had severe active and passive limitations in shoulder elevation, abduction and ER. With AROM and PROM being severely limited in all planes, I figured he'd be a slow responder, especially with resetting the cervical spine in WB not being effective.

The thought process was then to see if he could get to a farther end range in cervical retraction and SB toward the involved shoulder, since he met the Upper Quarter Clinical Practice Patterns. After suprisingly getting all of his elevation, ER, and abduction back I work the shoulder in the new range with some manual resistance.