NIH - What Is Back Pain? “What Are the Causes of Back Pain? There are many causes of back pain. Mechanical problems with the back itself can cause pain. Examples are: • Disc breakdown • Spasms • Tense muscles • Ruptured discs Injuries from sprains, fractures, accidents, and falls can result in back pain. Back pain can also occur with some conditions and diseases, such as: • Scoliosis • Spondylolisthesis • Arthritis • Spinal stenosis • Pregnancy • Kidney stones • Infections • Endometriosis • Fibromyalgia Other possible causes of back pain are infections, tumors, or stress.”

NIH - Medical Encyclopedia Back pain - low "The specific structure in your back responsible for your pain is hardly ever identified. Whether identified or not, there are several possible sources of low back pain: • Small fractures to the spine from osteoporosis • Muscle spasm (very tense muscles that remain contracted) • Ruptured or herniated disk • Degeneration of the disks • Poor alignment of the vertebrae • Spinal stenosis (narrowing of the spinal canal) • Strain or tears to the muscles or ligaments supporting the back • Spine curvatures (like scoliosis or kyphosis) which may be inherited and seen in children or teens • Other medical conditions like fibromyalgia."

Prolonged conservative care versus early surgery in patients with sciatica caused by lumbar disc herniation: two year results of a randomised controlled trial (BMJ 2008) “Conclusions Early surgery achieved more rapid relief of sciatica than conservative care, but outcomes were similar by one year and these did not change during the second year.”

Evidence-informed management of chronic low back pain with watchful waiting (The Spine Journal 2008) "After the common cold and other upper respiratory issues, LBP is the most common reason why medical attention is sought in the United States. The lifetime prevalence of LBP is estimated at 60% to 80% in industrialized nations. However, the presence of LBP does not necessarily require medical attention. Most cases occur without an obvious or diagnosable cause, and are self-limiting. Absent certain red flags indicative of serious pathology, care for LBP should generally begin with the least invasive option, as there is no evidence that more invasive approaches are more effective for nonspecific LBP."

Treatment of acute sciatica. (Am Fam Physician. 2007) "Acute sciatica is lower back pain with radiculopathy below the knee and symptoms lasting up to six weeks. … caused by a variety of conditions: disk herniation, lumbar spinal stenosis, facet joint osteoarthritis or other arthropathies, spinal cord infection or tumor, or spondylolisthesis. … Clinical Commentary: An efficient clinical history and thorough physical examination of a patient with suspected sciatica is needed to rule out urgent conditions like cauda equina syndrome, infection, or cancer, and to determine the need for diagnostic tests. After the acute episode, emphasis is placed on activity, back exercises, behavioral techniques, ergonomics education, and close clinical monitoring. Educating patients on self-care and establishing reasonable expectations usually increase patient compliance with therapy and improve satisfaction."