In order to elucidate the causes of degenerative spondylolisthesis (D.S), the functional role of lumbar intervertebral joints and also laminae of the vertebral arch was studied by means of roentgenographic and also pathological exams. The inclination of the laminae of the vertebral arch and the intervertebral joints changed with age in accordance with statokinetic loading of the lumbar spine. In the group with increased lumbar lordosis at the upper level, movement of the 3rd and 4th lumbar vertebrae was great, accompanied by horizontal inclination of the laminae of the vertebral arch and the intervertebral joints and by osteoarthritic changes (O.A). This is similar to D.S. D.S is caused by abnormal spinal curvature and structural specificity of the lower limbs vertebrae, resulting in degeneration of the laminae of the vertebral arch and the intervertebral joints, changes in the inclination, decreased control of movement, and sliding of the vertebrae. Prodromal conditions resulting in the sliding of the vertebrae and in disc degeneration appear to be caused by D.S.