Anterior versus posterior lumbar interbody fusion: Does cage geometry matter more than surgical approach?

Abstract

Background: For patients undergoing lumbar fusion, a variety of interbody arthrodesis techniques and devices exist, but few studies have evaluated the effect of cage geometry on radiographic outcomes. Thus, the purpose of this study is to compare the performance of expandable lordotic posterior lumbar interbody fusion (ePLIF) cages to lordotic anterior lumbar interbody fusion (ALIF) cages and to compare the early radiographic outcomes of different cage designs through review of the available literature. Materials and Methods: This is a retrospective case–control study, including 31 ePLIF and 36 ALIF levels, for the treatment of lumbar radiculopathy. Three-dimensional computed tomography scans were used to measure disc height, interbody angle, and foraminal height, both pre- and postoperatively. Implant geometry and positioning were then correlated with radiographic outcomes. The available ALIF and PLIF literature was then analyzed to determine the radiographic outcomes for each surgical technique based on cage geometry. Results: ePLIF cages increased foraminal height (P Conclusion: ePLIF cages are able to restore foraminal and disc height comparable to ALIF cages. However, lordotic ALIF cages should be utilized if sagittal restoration is a priority. Future studies are necessary to further explore the value of different implant design options. Level of Evidence: Level III. Clinical Relevance: Patients with abnormal sagittal balance should undergo a lordotic ALIF procedure. Patients who are sagittally balanced, however, can achieve fusion and decompression with either ALIF or ePLIF.