I was listening to an overview of the history, theory and practice of Tantra.  I was sitting cross legged and was performing various Yin moves for neck, shoulders and breath.  When the chapter ended a total body energetic rush moved up my torso.  That is when the warmth surrounded my spine.  It then encompassed my shoulder, neck and upper back.  There was an ease in my scapula.  It was as thought it was targeting my old injury for healing.