P118. Anterior versus lateral lumbar fusion: a comparison of 2-year outcomes in the treatment of degenerative spinal disorders

Abstract

<h3>BACKGROUND CONTEXT</h3> Extreme lateral interbody fusion (XLIF) and anterior lumbar interbody fusion (ALIF) have both been progressively utilized by spinal surgeons, offering advantages of reduced tissue trauma, blood loss and improvements in postoperative patient reported outcomes. Although the literature has reported a higher proportion of neurological complications in XLIF, the anterior approach has been associated with a larger overall complication proportion, including a greater number of vascular and visceral complications. However, there is a paucity of reports comparing the two approaches over the long-term. Therefore, the purpose of this study was to assess and compare the overall revision rates, perioperative complications and functional clinical outcomes with minimum 2-year followup in both ALIF and XLIF. <h3>PURPOSE</h3> To compare ALIF versus XLIF in the treatment of degenerative spinal disorders with minimum 2-year followup. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort comparative study. <h3>PATIENT SAMPLE</h3> A total of 293 patients from 2013-2018 with a minimum follow-up of 2 years. One hundred and seventy-eight patients underwent ALIF and 115 patients underwent XLIF. <h3>OUTCOME MEASURES</h3> (1) Revision rate and average time to revision; (2) Perioperative complications; (3) Functional outcome scores including Oswestry Disability Index (ODI) and Visual Analog Scale for back (VAS-b). <h3>METHODS</h3> A retrospective review was performed to identify all patients between 2013-2018 who underwent ALIF or XLIF for degenerative lumbar spinal disorders with a minimum followup of 2 years. Demographic data was recorded and compared between both cohorts. Revision rates and time to revision in each group were compared. Perioperative complications were recorded. Functional outcomes were assessed with ODI and VAS back measurements at followup visits. Standard binomial and categorical comparative analyses were performed. <h3>RESULTS</h3> A total of 293 patients were included, 178 in the ALIF cohort and 115 in the XLIF cohort. Mean followup for the XLIF and ALIF groups were 46.3 and 42.2 months, respectively. The overall revision rate was 7.8% for the XLIF group and 7.9% for the ALIF group (p= 0.990). The average time to revision was 270.1 ± 133.0 days and 301.1 ± 140.7 days for the ALIF and XLIF groups, respectively (p= 0.058). The most common reason for revision in each cohort was persistent radiculopathy in the ALIF group (57.1%) and symptomatic adjacent segment disease in the XLIF group (44.4%). Three patients (1.7%) in the ALIF group required intraoperative repair of the common iliac vein due to incidental transection perioperatively whereas one patient (0.9%) underwent repair of the dura due to incidental durotomy in the XLIF cohort (p= 0.557). There were 46 males and 69 females in the XLIF cohort compared to 89 males and 89 females in the ALIF cohort (p= 0.094). Both cohorts experienced significant improvements in their functional outcomes scores compared to their preoperative values. VAS scores decreased by a mean of 5.6 in the XLIF group and a mean of 2.5 in the ALIF group, a significant difference (p= <0.001). <h3>CONCLUSIONS</h3> Our 2-year results show revision and overall complication rates did not differ significantly between XLIF and ALIF after 2-year followup. However, the ALIF group had a larger number of complications which were all related to vascular injury. Regarding patient reported outcomes, the XLIF cohort had significantly greater VAS-b score improvement compared to the ALIF cohort. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.