Most lower back pain arises from minor irritations with the joints, muscles or ligaments in the area. Even small injuries to the area brought on by lifting, bending, twisting or repetitive movements can result in back pain. Fortunately, much of this pain will resolve on its own with a little bit of rest, some ice and time. If back pain persists and continues to be aggravated, it can develop into something a little more complicated.
Between each segment of the lower back, nerve roots exit the spinal cord sandwiched between the vertebral disc in the front and the spinal joint in the back. Your body will tolerate a certain degree of inflammation and injury to this area without any significant problems, but once it reaches a certain threshold, the nerve can be compromised. This process is not clearly understood, but suffice it to say that too much mechanical or chemical stress in the region will irritate the sensitive nerve root and cause symptoms wherever the nerve extends. In the case of the lower back, this usually means deep aching or numbness down the back of the leg and even down into the toes. In this case, even though it is the legs that seem to be hurting, no amount of therapy to the legs will help, but a chiropractic adjustment on the lower back can resolve the symptoms quickly. Once the irritation and inflammation is removed from the spine the nerve symptoms disappear.