P121. Fusion rate for stand-alone lateral lumbar interbody fusion: a systematic review

Abstract

BACKGROUND CONTEXT Lateral lumbar interbody fusion (LLIF) is used to treat several conditions, including spondylolisthesis, degenerative disc disorders (DDD), adjacent segment disease (ASD) and degenerative scoliosis. While many advocate for posterior fixation with LLIF, stand-alone LLIF is increasingly being performed. PURPOSE The fusion rate for stand-alone LLIF is currently unknown. STUDY DESIGN/SETTING Systematic review. PATIENT SAMPLE N/A OUTCOME MEASURES Reported LLIF fusion rate. METHODS We queried MEDLINE, COCHRANE, and EMBASE for literature on stand-alone LLIF fusion rate with a publication cutoff of December 2018. LLIF surgery was considered stand-alone when not paired with posterior fixation. Cohort fusion rate differences were calculated and tested for significance (p<0.05). All reported means were pooled. RESULTS A total of 2,395 publications were assessed. Nineteen studies met inclusion criteria, including 663 patients and 1,025 vertebral levels. Mean age was 57.1 years with BMI 26.4 kg/m2. Mean fusion rate was 85.3% (range, 53.0%-100.0%). By number of levels, fusion rate was 89.2% (1-level), 90.5% (2-level), and 96.8% (≥3-level). Use of rhBMP-2 was reported in 32.6% of subjects. There was no difference in fusion rates between studies using rhBMP-2 (87.4%) and those in which rhBMP-2 was not used (83.9%, OR=1.33, p=0.553). Fusion rate was highest in DDD (100%) and lowest in ASD (54.0%). Fusion rate differences were not noted across construct types. All-complication rate was 32.7% and mean reoperation rate was 10.7%, with 2.0% reoperation due to pseudarthrosis. Of the studies comparing stand-alone to circumferential fusion, pooled fusion rate was found to be 78.9% vs 92.1% (p=0.428). CONCLUSIONS Stand-alone LLIF yields high fusion rates overall. The wide range of reported fusion rates and lower fusion rates in studies involving subsequent surgical reoperation highlights the importance of employing a rigorous algorithm when indicating patients for stand-alone LLIF. Future research should focus on examining risk factors and patient-reported outcomes in stand-alone LLIF. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs. Lateral lumbar interbody fusion (LLIF) is used to treat several conditions, including spondylolisthesis, degenerative disc disorders (DDD), adjacent segment disease (ASD) and degenerative scoliosis. While many advocate for posterior fixation with LLIF, stand-alone LLIF is increasingly being performed. The fusion rate for stand-alone LLIF is currently unknown. Systematic review. N/A Reported LLIF fusion rate. We queried MEDLINE, COCHRANE, and EMBASE for literature on stand-alone LLIF fusion rate with a publication cutoff of December 2018. LLIF surgery was considered stand-alone when not paired with posterior fixation. Cohort fusion rate differences were calculated and tested for significance (p<0.05). All reported means were pooled. A total of 2,395 publications were assessed. Nineteen studies met inclusion criteria, including 663 patients and 1,025 vertebral levels. Mean age was 57.1 years with BMI 26.4 kg/m2. Mean fusion rate was 85.3% (range, 53.0%-100.0%). By number of levels, fusion rate was 89.2% (1-level), 90.5% (2-level), and 96.8% (≥3-level). Use of rhBMP-2 was reported in 32.6% of subjects. There was no difference in fusion rates between studies using rhBMP-2 (87.4%) and those in which rhBMP-2 was not used (83.9%, OR=1.33, p=0.553). Fusion rate was highest in DDD (100%) and lowest in ASD (54.0%). Fusion rate differences were not noted across construct types. All-complication rate was 32.7% and mean reoperation rate was 10.7%, with 2.0% reoperation due to pseudarthrosis. Of the studies comparing stand-alone to circumferential fusion, pooled fusion rate was found to be 78.9% vs 92.1% (p=0.428). Stand-alone LLIF yields high fusion rates overall. The wide range of reported fusion rates and lower fusion rates in studies involving subsequent surgical reoperation highlights the importance of employing a rigorous algorithm when indicating patients for stand-alone LLIF. Future research should focus on examining risk factors and patient-reported outcomes in stand-alone LLIF.