Single-Position Prone Lateral Interbody Fusion is Associated with Improved Radiographic and Clinical Outcomes at One Year compared to Single-Position Lateral Interbody Fusion: A Single Institution Experience.

Background: Recent studies highlight the increasing adoption of single-position prone lateral(SP-PL) and single-position lateral decubitus(SP-LD) in Minimally Invasive Spine Surgery(MISS) to reduce operative time, enhance patient safety, and improve surgical accessibility.

Objective: To assess the differences between SP-PL and SP-LD achievement of optimal postoperative outcomes and post-operative complication rates.

Study design: Retrospective review of prospectively collected MIS database.

Methods: Consecutive series of 152 Patients with baseline(BL) and 1-year(1Y) postoperative radiographic/HRQL data were included. Patients placed in the SP-PL or SP-LD were isolated. Optimal Outcome(OO) was defined as patients who experienced no complication requiring reoperation and achieved Substantial Clinical Benefit(SCB) for NRS-leg or NRS-back. Means comparison analysis assessed differences in radiographic and clinical outcomes. ANCOVA and multivariable backward stepwise logistic regression were used to adjust for confounders.

Results: 59 SP-PL and 93 SP-LD patients were included. At baseline, cohorts were comparable in terms of age, gender, BMI, and CCI. Peri-operatively, SP-PL patients had a significantly lower operative time(207.22 vs. 317.5 min;P<0.001), LOS(3.1 vs. 3.6 days;P=0.033), EBL(244.5 vs. 376.3 mL;P=0.023), and demonstrated lower perioperative complication rate(25.4% vs. 41.9%;P=0.038). Multivariable analysis indicated that SP-PL patients had a lower likelihood of cardiac perioperative complications(OR 0.012;CI95%: 0.0-0.6;P=0.026). Immediate postoperatively, SP-PL has a greater degree of segmental lordosis improvement from L1-L2 to L5-S1(all;P<0.05). SP-PL patients have a higher likelihood of achieving SCB NRS-Back at 1Y(OR: 8.0;CI95%: 1.5-42.0;P=0.014) and MCID NRS-leg at 1Y(OR:4.6;CI95%:1.002-21.2;P=0.49). The SP-PL cohort had a significantly greater percentage of OO(96.6% vs. 78.5%;P=0.002) and a higher likelihood of achieving OO in adjusted analysis (OR:10.6;CI95%: 2.1-53.3;P=0.004).

Conclusions: Patients placed in the SP-PL during minimally invasive spine surgery exhibit a reduced rate of perioperative complications, higher incidence of SCB, and a superior rate of achieving optimal outcome at the one-year follow-up. These findings underscore the SP-PL position as a potentially advantageous approach for minimally invasive lumbar fusion.