Bilateral Pedicle Screw Fixation Vs Unilateral Pedicle Screw Fixation for Single Level Lateral Lumbar Interbody Fusion: Outcomes, Cost Analysis, and Radiation Exposure

<h3>Background</h3> This study aims to determine whether single-level lateral lumbar interbody fusion (LLIF) with unilateral pedicle screw fixation (UPSF) might offer advantages over bilateral pedicle screw fixation (BPSF) in terms of radiation emission, cost, and outcomes. <h3>Methods</h3> The records of 101 patients who underwent single-level LLIF with percutaneous pedicle screw fixation from September 2017 to August 2024 were analyzed. Patients were divided into 2 groups: 42 with UPSF and 59 with BPSF. Demographic data, social history, comorbidities, surgical characteristics, costs (based on manufacturer prices), and radiation metrics (radiation emitted, fluoroscopy time, number of images, and magnification mode used) were collected. Clinical outcomes were assessed using the Numeric Rating Scale (NRS), the Oswestry Disability Index, and procedure satisfaction, while radiographic evaluation employed a novel fusion classification system. <h3>Results</h3> There were no significant differences in age, body mass index, social history, comorbidities, or operative level. However, the BPSF group included significantly more women (<i>P</i> = 0.002) and a higher proportion of spondylolisthesis cases (<i>P</i> &lt; 0.001). Oswestry Disability Index and NRS scores were similar, except for greater improvements in NRS back pain at 1 year in the BPSF group (−4.0 vs −1.75, <i>P</i> = 0.008). While the total fluoroscopy time, number of images, and Mag 1 usage were greater in the BPSF group (all <i>P</i> &lt; 0.001), the average radiation emitted did not significantly differ (39.38 milligray for UPSF vs 50.75 milligray for BPSF, <i>P</i> = 0.211). Fusion grades were comparable (<i>P</i> = 0.478), and UPSF costs were 27.7% lower. <h3>Conclusions</h3> Our study found that when used according to clinical indications, UPSF results in similar radiation emission and radiographic outcomes, while being 27.7% less expensive than BPSF for single-level LLIF. Additionally, while BPSF was associated with greater improvement in 1 year NRS back scores, no other significant differences in patient-reported outcome measures were observed between the 2 groups. <h3>Clinical Relevance</h3> This study provides clinically relevant insights for selecting between UPSF and BPSF in single-level LLIF when both are considered appropriate. <h3>Level of Evidence</h3> 3.