A new technique for the reduction and stabilisation of severe spondylolisthesis. A report of nine cases.

A one stage operation by the posterior route has been carried out in a series of nine patients for the reduction and fusion of severe spondylolisthesis and spondyloptosis. For this purpose special instruments have been designed to exert a controlled force on the displaced vertebra in two perpendicular directions. Technical details of the procedure are reported. Bone is resected from the sacrum and the fifth lumbar vertebra to avoid too much tension on the nerve roots. After the reduction L5 is held in place by two screws and a sacral bar. The lumbosacral kyphosis seen in severe spondylolisthesis can also be corrected by this method. Bone grafts from the ileum or tibia are not needed and lumbosacral fusion is achieved within 3-6 months because of the close contact between the raw bone of the vertebral bodies. All patients achieved a sound fusion with significant remission of symptoms.