Three-column osteotomy in long constructs has lower rates of proximal junctional kyphosis and better restoration of lumbar lordosis than anterior column realignment.

PURPOSE: Three-column osteotomies (TCOs) and minimally invasive techniques such as anterior column realignment (ACR) are powerful tools used to restore lumbar lordosis and sagittal alignment. We aimed to appraise the differences in construct and global spinal stability between TCOs and ACRs in long constructs. METHODS: We identified consecutive patients who underwent a long construct lumbar or thoracolumbar fusion between January 2016 and November 2021. "Long construct" was any construct where the uppermost instrumented vertebra (UIV) was L2 or higher and the lowermost instrumented vertebra (LIV) was in the sacrum or ileum. RESULTS: We identified 69 patients; 14 (20.3%) developed PJK throughout follow-up (mean 838 days). Female patients were less likely to suffer PJK (p = 0.009). TCO was more associated with open (versus minimally invasive) screw/rod placement, greater number of levels, higher UIV, greater rate of instrumentation to the ilium, and posterior (versus anterior) L5-S1 interbody placement versus the ACR cohort (p < 0.001, p < 0.001, p < 0.001, p < 0.001, p = 0.005, respectively). Patients who developed PJK were more likely to have undergone ACR (12 (32.4%) versus 2 (6.3%, p = 0.007)). The TCO cohort had better improvement of lumbar lordosis despite similar preoperative measurements (ACR: 16.8 ± 3.78°, TCO: 23.0 ± 5.02°, p = 0.046). Pelvic incidence-lumbar lordosis mismatch had greater improvement after TCO (ACR: 14.8 ± 4.02°, TCO: 21.5 ± 5.10°, p = 0.042). By multivariate analysis, ACR increased odds of PJK by 6.1-times (95% confidence interval: 1.20-31.2, p = 0.29). CONCLUSION: In patients with long constructs who undergo ACR or TCO, we experienced a 20% rate of PJK. TCO decreased PJK 6.1-times compared to ACR. TCO demonstrated greater improvement of some spinopelvic parameters.

Lateral Anterior Column Release in Short Lumbar Fusion Is it worth it?

INTRODUCTION: Radiographic ASD ranges from 10% to 84%, depending on technique. Occurrence of symptomatic ASD is lower, with a range of 1.9% to 13%. ASD can be very debilitating and necessitate further procedures, leading to high morbidity. Herein, we explore the occurrence of adjacent segment disease when performing anterior column release in lateral interbody fusion. METHODS: After IRB approval, 120 total patients who underwent LLIF at our facility from 2013 to 2020 were retrospectively reviewed, allowing for a minimum of 3 years for follow up time. Surgical variables and spinopelvic parameters were measured and collected by our team. Statistical measures of significance were calculated using IBM SPSS Statistics Version 29. RESULTS: 120 total patients were included. 73.3% of patients had percutaneous screws, and 11.7% had open. 13 patients underwent LLIF with ACR. The mean LL was 50.1± 12.9, PI was 52.8 ± 11.2, SS was 33.6± 9.2, PT was 18.1 ± 6.8, and SVA was 6.8 mm ± 30.5. 24 total patients had ASD after LLIF. In univariable analysis, ACR (P<0.001) and PI-LL Mismatch (P<0.035) were risk factors for developing ASD. In multivariable analysis, greater PI-LL mismatch was predictive of ASD (p<0.005, OR=1.097, and 95% CI=1.029-1.171), as was ACR (p<0.001, OR=9.667, and 95% CI=2.669-35.09). CONCLUSION: Higher PI-LL mismatch after lumbar interbody fusion, and performance of an ACR during LLIF increased the likelihood of developing symptomatic ASD in our patients. Considering ACR to achieve the goal of correcting spinopelvic parameters should be carefully evaluated when undertaking a lateral approach.