The main causes of lumbar spondylolisthesis can be broadly divided into congenital and acquired factors (degenerative changes).
The specific causes of congenital lumbar spondylolisthesis are unknown and may be related to separation of the nucleus pulposus (a deformity during development), hereditary dysplasia, birth injuries, and mechanical factors.
Degenerative slippage is mainly caused by degeneration of the lumbar discs, ligamentous laxity and degenerative lesions of the small posterior joints and may be associated with changes in the loss of the intervertebral disc space, excessive lumbar lordosis, obesity, pregnancy, ligamentous laxity, osteoporosis, post-menopause or post-ovariectomy, diabetes mellitus and also sacralisation of the 5th lumbar vertebra.