Is the antepsoas oblique lumbosacral interbody fusion safe in patients with aortoiliac calcification?

Background: The anterior approaches to lumbar arthrodesis, including direct anterior (ALIF) and antepsoas (ATP)/oblique (OLIF) fusions, require careful manipulation of the abdominal prevertebral vessels for safe and adequate spinal access. Therefore, surgeons who perform anterior lumbar fusions in patients with aortoiliac calcifications are often cautious due to concerns for perioperative vascular complications, as well as the associated risks of concomitant medical comorbidities. This study sought to compare the incidence of perioperative vascular and medical complications in patients with and without abdominal aortoiliac calcification (AAC) undergoing the minimally invasive antepsoas (MIS-ATP) lumbosacral fusion. Methods: This was a retrospective matched cohort study including 482 adult patients undergoing MIS-ATP lumbosacral fusions at a single institution between 2014 and 2020 (227 with AAC and 255 without AAC), matched by sex and American Society of Anesthesiologists (ASA) scores. Through preoperative standing lateral lumbar radiographs, using Kaupilla et al.'s AAC grading system, we graded anterior and posterior aortic wall calcification from L1 to L4. Electronic medical records were reviewed to identify and collect the perioperative complications. Results: While there was no occurrence of intraoperative vascular injuries in either group, patients with AAC were more likely to develop medical complication (34.8% vs. 13.3%, p < .001), with anemia (18.9% vs. 9.2%), ileus (16.3% vs. 2.7%) and acute kidney injury (6.6% vs. 5.5%) being the most common. Overall, individuals with AAC had 2.62 times increased odds of developing a postoperative medical complication. Moreover, moderate AAC was found to be a significant risk factor (OR = 3.48). Conclusions: Presence of AAC in patients undergoing MIS-ATP fusion was not associated with increased risk of direct surgical or exposure related vascular complications. However, patients with AAC were significantly more likely to experience medical complications following MIS-ATP fusion.