Comparison of ALIF and PLIF in Isthmic Lumbosacral Spondylolisthesis. A Multicenter Surveillance Study of 602 cases from the German Spine Registry (DWG Register).

Background:  Isthmic spondylolisthesis most commonly occurs in the lumbosacral junction and can cause backpain and radicular pain as well as stiffness with progressive immobilization, with a negative impact on an individual's ability to work and quality of life. Multiple operative treatments are currently available. This study aims to compare complications, demography, and clinical features between anterior lumbar interbody fusion (ALIF) and posterior lumber body fusion (PLIF) in the operative treatment in isthmic spondylolisthesis.

Methods:  An analysis of data from the German spine registry (Deutsche Wirbelsäulengesellschaft [DWG]-Register) of patients who underwent operative treatment (PLIF and ALIF) for isthmic spondylolisthesis in the sacrolumbar junction in 170 departments between January 2017 and May 2021 was performed. Age, gender, American Society of Anesthesiologists (ASA) score, surgical approach, smoker/nonsmoker, as well as severeness of the spondylolisthesis according to the Meyerding classification were evaluated.

Results:  In total, 602 patients undergoing fusion in L5/S1 were identified in the registry, n = 570 PLIF (group 1) and n = 32 ALIF (group 2). A significant difference in the ASA score between the two groups was noted; group 1 had more patients suffering a more debilitating disease in comparison to group 2. There was no significant difference in gender, grade of spondylolisthesis, age, or smoking status. Significant differences were found in operative and postoperative variables and complications (fusion material, dura injury).

Conclusion:  No difference was found between the two procedures in terms of symptomatic benefit of patients who underwent either ALIF or PLIF. According to the DWG Register, PLIF was the preferred method to treat isthmic spondylolisthesis in the sacrolumbar junction in Germany. To compare these two spine fusion techniques, further studies with an adequate sample size and follow-up period are required.