BACKGROUND:Lumbar spinal stenosis is clinical repaired with decompression, bone fusion and internal fixation, and different internal fixation materials can be chosen during the surgery. OBJECTIVE:To explore the influence of polyetheretherketone (PEEK) pedicle screw fixation combined with interbody fusion on the bone fusion rate of patients with lumbar spinal stenosis. METHODS:A retrospective analysis was performed in 63 cases of lumbar spinal stenosis undergoing decompression and interbody fusion. These patients were divided into control group (titanium internal fixation system,n=31) and experimental group (PEEK pedicle internal fixation system,n=32) according the internal fixation materials folowed by posterior spinal decompression with interbody fusion. The Oswestry dysfunction index scores before and 4, 12, 24 weeks postoperatively and bone fusion rates at 4, 12, 24 weeks postoperatively were compared between the two groups. RESULTS AND CONCLUSION:Oswestry dysfunction index scores showed a gradual decline in both two groups before and 4, 12 and 24 weeks after treatment, but there was no difference at different time (P > 0.05). At 4 and 24 weeks after treatment, there was no difference in the bone fusion rates between the two groups (P > 0.05), but at 12 weeks after treatment, the bone fusion rate in the experimental group was better than that in the control group (P < 0.05). During the surgery, no infection and other adverse events occurred in the two groups. These results indicate that both PEEK and titanium internal fixation systems for lumbar tube stenosis have obtained good results, but PEEK material has a better role in the bone fusion at 4-12 weeks after internal fixation.