Low Back Pain Low back pain is usually defined as either acute or chronic. Physicians diagnose low back pain as acute if it lasts less than a month and is not caused by serious medical conditions. Most cases clear up in a few days without medical attention, although recurrence after a first attack is common. Back pain may be triggered by various problems that occur along the ridge of bone and disc. Injuries and small fractures can occur.
Muscle spasms can cause pain.
Pressure on a weakened disc may cause it to rupture so the nucleus pulposus protrudes out from the spinal column, a condition known as a herniated disc. The facets can become misaligned or deteriorate. The spinal canal itself can become narrowed, a disorder called spinal stenosis. If any of these conditions occur, the nerve roots passing between the discs and facets may be stretched or pinched, causing low back pain, often the pain known as sciatica. The nerve most likely to cause trouble is the sciatic nerve.