Surgical management of isthmic spondylolisthesis: A comparative study of postoperative outcomes between ALIF and TLIF

Introduction: Circumferential fusion by the anterior (ALIF) or transforaminal (TLIF) approach combined with posterior instrumentation is currently used for the surgical treatment of low-grade isthmic spondy-lolisthesis. But few studies have compared the clinical and radiological outcomes of various interbody fusion techniques. The objective of this study was to compare the clinical and radiological results at 2 years postoperative of two fusion techniques-TLIF versus ALIF plus posterior instrumentation-for low-grade isthmic spondylolisthesis in adults.Materials and methods: This was an observational multicenter study done at nine French healthcare facilities specialized in spine surgery. The inclusion criteria were minimum age of 18 years, grade 1-3 isthmic spondylolisthesis, ALIF + posterior fixation (ALIF + PS) or TLIF, minimum follow-up of 2 years. Clinical and radiological evaluations were done preoperatively and at 2 years of follow-up. A lumbar CT scan was done at 1 year postoperative to evaluate fusion. Results: The cohort consisted of 89 patients (50 women, 39 men) with a mean age of 47.7 +/- 12.3 (18-79) years. The patients in the ALIF groups (n = 71) had a significantly longer hospital stay than those in the TLIF group (n = 18): 5.7 days versus 4.6 days (p = .04). However, their medical leave from work was significantly shorter: 31.0 weeks versus 40.7 (p = .003). Lumbar pain VAS diminished faster in the ALIF groups, with a significantly larger drop than the TLIF group in the first 3 months postoperative. Only the increase in lumbar disc lordosis was larger in the ALIF group: 11.7 degrees +/- 12.0 degrees versus 6.0 degrees +/- 11.7 degrees (p = .036). There was a significant correlation between the increase in global lordosis and reduction in lumbar VAS at 2 years postoperative (p= - 0.3295; p = .021).Conclusion: ALIF + PS provides a faster relief of postoperative low back pain than TLIF but there are no significant clinical differences between techniques at 2 years of follow-up. Despite better restoration of disc lordosis in the ALIF + PS group, there was no difference in the restoration of global lordosis. Level of evidence: III; multicenter comparative study.(c) 2023 Elsevier Masson SAS. All rights reserved.