Most back pain is the result of inflamed and restricted joints. When a joint is inflamed the swelling present impedes normal joint movement. The inflammation further restricts normal movement by laying down adhesions or scar tissue around the joints.
Chiropractors identify these joint restrictions by finding vertebral segments that are inflamed and painful. The chiropractic adjustment restores normal joint movement by freeing up joint restriction and breaking scar tissue around joints. This allows the joint to work normally. Swelling subsides from the joints as there is no longer as much joint and ligament tension in the area.
Lower back pain can also be caused by injuries to the intervertebral disc, as in the animation below. In reality the disc doesn’t bulge out to the side as much as backwards towards the facet joints but for the purposes of this animation it is clear that disc injuries cause abnormal spinal movement. Chiropractic manipulation endeavours to increase mobility at the affected vertebral segment, reduce inflammation of the facet joints and the disc, and with various other techniques minimise the disc bulge and restore normal function.