Have you ever had back pain? After it went away, did it come back again? Did that motivate you to do more ab and core work? Did it still come back? The recurrence of back pain despite doing back and core stabilization exercises may indicate there is a missing ingredient to the current model of core exercise programs.
Read the reasons for including deep breathing in your core training program here: http://breakingmuscle.com/mind-body/how-abs-of-steel-cause-back-pain
If you are dealing with back pain and looking for a safe and gentle program to help build strength and mobility, The Posture Project will help: http://www.bountifulyogaandwellness.com/the-posture-project/