The low back is equally complex as the neck and upper back. The psoas muscles (hip flexors) are related to the upper neck, meaning the front of your low back is controlled partly by your neck stability. The pelvis also plays a massive role in low back pain. It is the foundation of your whole spine. If the foundation is torqued out of place, the sacrum twisted or the whole pelvis unstable, that will 100% need to be corrected before low back pain can go away.