Abstract
Introduction
Posterolateral Fusion (PLF) and Posterior Lumbar Interbody Fusion (PLIF) are procedures that can be undertaken for the surgical management of degenerative low grade spondylolisthesis. Although there is tentative evidence in the literature that PLIF provides an increased fusion rate and therefore an improvement in symptomology, PLIF surgery does carry an increased peri- and post-operative complication rate. The aim of this study was to establish which surgical intervention has the better outcomes.
Materials and Method
A prospective cohort study was undertaken of patients who underwent a single level instrumented fusion for low grade degenerative lumbosacral spondylolisthesis between 2008 and 2010. There were 56 patients in total, with 36 patients in the PLF group (group1), and 20 patients in the PLIF group (group 2). Follow-up was at 3 month, 1 year and 3 year post operatively. Visual analogue leg pain score (VAS), Oswestry Disability Index (ODI) for back pain, and SF 12 Health Survey were measured pre and 3 year post operatively. All patients were assessed by MRI scans preoperatively. Standardized lumbosacral radiographs were taken preoperatively, and at 3 month, 1 year and 3 year postoperatively, to assess radiological union.
Results
In the PLF group, the VAS score improved from 8 to 2, the SF 12 score from 25 to 76, and the ODI score from 36 to 8. In the PLIF group, the VAS score improved from 8 to 4, the SF 12 score from 27 to 72, and the ODI score from 38 to 12. All improvements were statistically significant. There was a statistically larger improvement margin in all scores in the PLF group than in the PLIF group. Radiological union was demonstrated in 91% of all patients, with 95% of patients in each group demonstrating at least, unilateral lateral mass bone graft incorporation.
Conclusion
We conclude that PLF surgery is superior to PLIF surgery for the surgical management of low grade single level degenerative spondylolisthesis