Thursday, September 27, 2018 1:05 PM–2:05 PM Lumbar Spine Surgery: What You Need to Know: 114. No difference in reoperation rates or outcomes for a two-level posterolateral fusion augmented with single- versus two-level transforaminal lumbar interbody fusion

Abstract

BACKGROUND CONTEXT Interbody devices (IBD) are being increasingly utilized during lumbar fusions with reported benefits, when compared to posterolateral fusion (PLF) alone, including increased fusion rates, increased neuroforaminal height, and the potential for improved sagittal alignment. Moreover, use of IBD has been shown to reduce reoperation rates compared to PLF alone. Although excellent outcomes have been demonstrated for single level transforaminal lumbar interbody fusion (TLIF), outcomes for single level TLIF in the setting of multiple level PLF are unknown. Some have suggested that a single level TLIF in the setting of a two level PLF may lead to increased pseudarthrosis at the level without an IBD, perhaps secondary to differences in stiffness at those levels in the setting of a developing fusion. PURPOSE We aim to determine whether there are differences in reoperation rate and outcomes for patients undergoing two level PLF augmented by a TLIF at only one of the levels vs at both levels. STUDY DESIGN/SETTING Retrospective, single institution, multi-surgeon patient cohort. PATIENT SAMPLE From September 2012 through September 2017, 416 patients were identified who underwent two level PLF with a TLIF at either one of those levels (n=183) or at both (n=233) with greater than one year follow-up. The two level TLIF group was significantly younger than the single level TLIF group (60.2 vs. 63.7, p=0.001), had a significantly lower Charleston Comorbidity Index (0.32 vs. 1.21, p OUTCOME MEASURES Primary outcome was reoperation rate with secondary outcomes including surgical parameters (estimated blood loss [EBL], OR time, length of stay [LOS]) and patient reported outcome measures (ODI, SF-12). METHODS T-tests were used to compare the cohorts for continuous variables and Chi square tests were used to compare the groups on categorical variables. RESULTS The one level and two level TLIF groups underwent 24 reoperations for 25 complication types and 24 reoperations for 27 complication types, respectively. Although the number of overall reoperations was not significantly different (p>0.05), among the reoperation types, there were significantly more reoperations for adjacent segment disease in the two level group compared to the one level group (19 vs. 12, p=0.04). There was no difference in reoperation for pseudarthrosis between the groups (p>0.05). Although the two level group had a higher EBL (p=0.002), they had an overall shorter LOS (p=0.003) (likely because they were younger and healthier to start). Although both groups experienced significant improvements in ODI (p CONCLUSIONS For patients undergoing two level PLF in the setting of a TLIF, using a TLIF at one vs both levels does not seem to influence reoperation rates or outcomes. However, reoperation rates for adjacent segment disease are increased in the setting of a two level PLF augmented by two TLIFs. FDA DEVICE/DRUG STATUS All devices were FDA approved and used as instructed.