1, lumbar sprain 70%; 2, lumbar degeneration 10%; 3, disc herniation 4%; 4, lumbar spinal stenosis 3%; 5, compression fracture 4%; 6, lumbar spondylolisthesis 2%; 7, traumatic fracture <1%; 8, congenital deformity: severe retrognathism or scoliosis, displaced vertebrae <1%; 9, isthmic fracture; 10, internal rupture of the intervertebral disc; 11, possible instability.