Introduction: Operative management normally involves an anterior lumbar interbody fusion (ALIF) or posterior lumbar interbody fusion (TLIF/PLIF). Each procedure has surgical risks and benefits; however, few reports with conflicting findings characterize early outcomes. Our objective is to compare the two surgical approaches for elective single-level fusions based on the following outcomes: operation time, hospital length of stay (HLOS), early complications, discharge destination, reoperation and mortality.
Methods: Adult patients undergoing elective single-level ALIF or TLIF/PLIF operations were abstracted from American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) years 2011-2014. Univariate analyses were performed by surgery cohort for each outcome, and corrected for demographic/clinical variables (age=65, sex, race, body mass index (BMI), American Society of Anesthesiologists physical classification (ASA) score, functional status, inpatient/outpatient status, smoking, hypertension, Charlson Comorbidity Index) using multivariable regression. Significance was assessed at p<0.05.
Results: Of 8,263 subjects, ALIF subjects were younger (<65 years: 72.6% vs. 64.4%; p<0.001), less obese (BMI <30: 49.9% vs. 47.2%; p=0.001), less physically impaired (ASA 3-4: 38.5% vs. 43.6%, p=<0.001). On multivariate analysis ALIF associated with shorter operation time (B= -9.77-minutes, 95% CI [5.00, 14.53]; p<0.001), decreased blood transfusions (10.89% vs. 11.51%; p=0.085) and urinary tract infections (UTI) (1.20% vs. 1.83%; p=0.024). Multivariate analysis also demonstrated TLIF associated with shorter HLOS (B= -0.27-days, 95% CI[-0.54,-0.01]; p=0.041) and fewer cases of ventilator dependency (0.14% vs. 0.39%; p=0.017) and pneumonia (0.51% vs. 0.9%; p=0.027). Reoperation rates did not differ between surgical cohorts.
Conclusions: Patients undergoing ALIF procedures were healthier and younger. ALIF patients experienced decreased operative time and decreased likelihood of experiencing postoperative UTIs, however ALIF patients were more likely to experience postoperative pulmonary complications and longer hospital stays. Our data demonstrates that ALIF performs comparably to TLIF/PLIF in context of 30-day perioperative outcomes. Future studies are needed to confirm these findings.
Patient Care: Our data demonstrate that anterior vs. posterior fusion approaches are indicated in different patient populations. By characterizing peri-operative variables we hope to further inform surgical decision-making and improve patient outcomes.
Learning Objectives: At the conclusion of our presentation participants will be able to:
1) Characterize differing patient populations that undergo either anterior or posterior lumbar interbody fusion.
2) Understand the risks and benefits associated with each procedure (ALIF vs. TLIF/PLIF) in context of one of the largest samples of patients heretofore studied.