Provided Back pain can be caused by a multitude of issues, but correcting how we sit, stand or walk can often have a huge impact on the overall health of our spine. Low back pain is one of the biggest complaints regarding ailments of the spine and many low back issues can stem from tight or weakened hip flexors, or tight and/ or weakened quadratus lumborum — the deepest abdominal muscle, located in your lower back on either side of the lumbar spine – causing imbalances in the sacroiliac joints. SI joints is where the top of your pelvis attaches to the lower part of your spine.