Efficacy of Posterior Lumbar Interbody Fusion using PEEK Cage and Pedicle Screw Stabilization in Degenerative Lumbar Spinal Disorders - Minimum 3 Years Follow up Results -

Study Design: A retrospective study. Objectives: To evaluate the three-plus year follow-up results of patients who underwent posterior lumbar interbody fusion with PEEK cage and pedicle screw fixation for lumbar degenerative disease. Summary of Literature Review: There are few previous reports addressing posterior lumbar interbody fusion using PEEK cage with mid-term follow up periods. Materials and Methods: 260 patients who underwent posterior lumbar interbody fusion with PEEK cage and pedicle screw fixation for lumbar degenerative disease were enrolled. We classified patients into three groups according to their fusion level: group A (n=151) had one-level fusion, and group B (n=91) had two-level fusion, and group C (n=18) had three-level fusion. Clinical outcomes were evaluated by pre- and post-operative Visual analogue scale (VAS) scores, the Oswestry Disability Index (ODI), and complication and reoperation rates. Radiologic outcomes were measured by the fusion rate, sagittal alignment, disc height and changes. Results: VAS (pre-operative to final follow-up) changed from 7.62±2.03 (5-10) to 3.19±1.94 (1-8) in group A, from 6.83±2.28(4-9) to 4.51±2.18(2-9) in group B and from 7.17±2.46 (5-10) to 4.63±1.97(1-9) in group C. Final follow-up ODI also decreased in group A (17.6±8.56%), group B (15.4±5.46%) and group C (24.7±7.46%). This corresponds to scores of 94.7% in group A, 92.3% in group B and 94.4% in group C. There were significant differences between preoperative, post-operative and final follow-up lumbar lordosis [p=0.042(group A), 0.036(group B), 0.045(group C)], segmental lordosis [p=0.036(group A), 0.039(group B), 0.047(group C)]. Reoperation was performed in patients 8 group A, 4 group B, and 1 group C, and there is no significant diffrence between groups. Adjacent segmental change was found in all reoperation patients, but showed no correlation with clinical results. Conclusions: Posterior lumbar interbody fusion with PEEK cage and pedicle screw fixation in lumbar degenerative disease showed excellent clinical results and fusion rates, regardless of patient fusion levels.