1. Prespondylolisthesis is a competent cause of backache and back disability.
2. Prespondylolisthesis is the forerunner of a spondylolisthesis.
3. Prespondylolisthesis may remain asymptomatic for many years, or throughout life.
4. The most active period of life, thirty to fifty years, has shown the largest incidence of prespondylolisthesis in the author's group.
5. The chief clinical features of prespondylolisthesis are: (a) low back pain; (b) stiffness of back; (c) sciatic pain; (d) localized tenderness at the lumbosacral area. Lordosis is often present, but is not a constant finding.
6. The essential pathological lesion is a bilateral defect in the neural arch at the pedicles.
7. The most effective treatment is surgical, consisting of a fusion of the lower three lumbar vertebrae to the sacrum.