Objective To evaluate the outcome of two methods for stabilization and fusion: posterolateral fusion and circumferential fusion involving posterior lumbar interbody fusion for lumbar stenosis with Grades 1 and 2 lumbar spondylolisthesis.Methods From April 1998 to April 2003

45 patients suffering from lumbar stenosis with low degree lumbar spondylolisthesis treated in our hospital were retrospectively reviewed and assigned to two groups.Among them

24 patients （group A） were treated with instrumented posterolateral fusion and 21 patients （group B） with instrumented circumferential fusion.The two groups were compared for clinical and radiological outcomes.Results All patients were followed up for 12 to 72 months.In group A

results showed preoperative clinical symptoms disappeared completely in 12 of 24 patients

and pain relief was seen in 91.7% （22/24）.Two cases suffered from residual symptoms.Twenty-two cases obtained complete reduction of olisthy vertebral bodies

and anatomical reduction rate was 91.7%.No infection or neurological complication occurred in this group.In group B

results showed preoperative clinical symptoms disappeared completely in 13 of 21 patients

and pain relief was seen in 90.5% （19/21）.One case suffered from residual symptoms.Twenty cases obtained complete reduction of the olisthy vertebral bodies

and anatomical reduction rate was 95.2%.Four cases of infection or neurological complication occurred in this group.Both groups indicated no significant difference in clinical outcomes and anatomical reduction rate during follow-up.But group A had better intraoperative circumstances and postoperative outcome than group B

while group B had better postoperative parameters in X-ray of Angle of Slipping and Disc Index than group A.Conclusions The first choice of surgical method for lumbar stenosis with low degree lumbar spondylolisthesis is instrumented posterolateral fusion.Only when patients suffer from severe preoperative disc degeneration and low back pain or intervertebral instability should we consider indications for additional use of CAGE.