Hi, Sometimes when I stretch or move or bend my I listen some crunching type sounds mainly from upper part of my back. Also stretching my neck side to side gives this type of sound and when I lean my head backward I listen a popping type sound from near spinal cord and little bit of right side. Also when I try to expand my chest I feel little pain from the right side of my chest. Why are this things happening to me? Please tell me the causes and give some advice for me.