Low back pain, together woth shoulder and neck pain, affect millions of individuals, and is a very usual topic of concern. Frequently is associated with sciatica. Two different low back pain groups are reported: 1--Unspecific low back pain; 2--Organic low bck pain. Unspecific low back pain: two considerations must be present: a) Absence of clinical or radiological signs of concrete disease, and b) Presence of a psychological profile defined by a personality unable to live together with pain. Different pathogenic mechanisms have been invoked to explain the unspecific low back pain: disc herniation irritating the posterior disc ring and the common posterior vertebral ligament, arthritis of small and real--have synovial--, interapophyseal joints, trigger zones of local spasm in the spinal muscles, postural changes after having remained a long time in the same position, and for some few ones, ligament instability in the sacroiliac joint. Organic low back pain: characterized like congenital diseases, acquired diseases--discal herniation, spondylosis, lumbar spine stenosis--, And systemic diseases affecting the spine: aortoiliac chronic vascular disease and abdominal processes causing lumbar and buttocks pain. The therapeutic alternative is either conservative or surgical. Surgery is protagonist in post-traumatic unstale spine, in unstable spondylolisthesis, in spine persistent infections and in spine tumours. Also is subsidiary of surgical treatment the disc degeneration with nerve root irritation causing motor disturbance. The disc degeneration without root irritation precludes conservative management: percutaneous manual nucleotomy, coblation nucleoplasty or back schools programmes, defined like interventions consisting of education and skill programmes supervised by a physical therapist trained in back rehabilitation.