Have you looked upstream?
this 3 part series
Jill Miller Fixes Your T-Spine and Crappy Breathing Mechanics
Jill Miller Smashes Your Guts! (and psoas, and tacked down viscera, and matted down abdominals…) Part 2
Jill Miller Diaphragm Evolution Part 3: Eccentric Loading
Many times low back or thoracic problems are caused by bad diaphragm mechanics.