Perioperative Complication Associated with Greater Number of Anterior Lumbar Interbody Fusion Segments

Introduction: Anterior lumbar interbody fusion (ALIF) is a powerful technique that offers indirect decompression, stabilization, and correction of spinal deformity. Although incidence of complication is low, it remains unclear how multilevel ALIF affects perioperative risks. This study assesses whether increasing number of levels fused during ALIF is associated with complications.

Methods: A retrospective review of patients receiving ALIF surgery at our institution was performed from 2018 to 2022. Patient demographics, diagnosis, and surgical characteristics were recorded. Primary outcomes if interest was intra- and postop-complications. Multivariate logistic regression was to assess outcomes measures.

Results: A total of 418 patients were included. Mean age was 56.0 years and 49.2% were male. Segments fused were as follows: 1-level (48.2%), 2 levels (35.7%), 3 levels (12.3%), 4 levels (3.5%), 5 levels (0.2%). Overall complication rate was 20.6%: 6.9% intraoperative (1-level [3.4%], 2-level [10.1%], 3-level [8.0%], 4-level [13.3%], 5-level [100%]) and 15.1% postoperative (1-level [8.9%], 2-level [18.1%], 3-level [30.0%], 4-level [20.0%], 5-level [0%]). Intraoperative complications included 1 ureter injury (0.2%), 4 major vascular injuries (1.0%), and 23 minor vascular injury (5.5%). The most common post-op complication is ileus [requiring nasogastric tube decompression] (n=27; 6.5%) and DVT (n=8; 1.9%). Postoperative rate of foot drop was 1.2%, while other motor deficits were seen in 1.4%. Increasing levels of interbody fusion have significantly higher odds of major intraoperative vascular injury (1-level [0%], 2-level [1.3%], 3-level [2.0%], 4-level [0%], 5-level [100%] | OR: 3.34; p=0.017) and PE (1-level [1.0%], 2-level [1.3%], 3-level [2.0%], 4-level [13.3%], 5-level [0%] | OR: 2.31; p=0.028). While L4-5 was the most common level involved with vessel injury, there was no association between post-operative complications with specific operative levels.

Conclusion : While overall rates of complicates are low, additional levels of interbody fusion are associated with higher rates of vascular injury and PE. Consideration of this risk should be taken when planning surgical cases and disusing options with patients.