P109. Bridging the cervicothoracic junction during multi-level posterior cervical decompression and fusion -A systematic review and meta-analysis

BACKGROUND CONTEXT Several studies address the question of whether to extend a long-segment, posterior cervical fusions into the upper thoracic spine. Recommendations for appropriate caudal “end level” continue to vary. PURPOSE This systematic review seeks to compare fusion, reoperation and complication rates, estimated blood loss (EBL) and surgical time between multilevel instrumented fusions ending in the cervical spine and those that extend into the thoracic spine. STUDY DESIGN/SETTING Systematic review and Meta-analysis. OUTCOME MEASURES Fusion, reoperation and complication rates, EBL and surgical time. METHODS A comprehensive computerized literature search through multiple electronic databases without date limits up until April Week 3 2020 using combinations of key search terms and inclusion/exclusion criteria was performed. RESULTS Our comprehensive literature search yielded 3,852 studies. Of these, 8 articles consisting of 1,162 patients were included in the meta-analysis. In 61.2% of the patients the fusion did not cross the CTJ (the cervical end level CEL). In the remaining 38.8%, fusion extended into the upper thoracic spine (thoracic end level, TEL). Mean age of CEL group ranged from 57 to 67.8 years, and for TEL group, it was 55 to 65.3 years. Our direct analysis showed that odds of fusion were not statistically different between CEL and TEL groups (OR: 0.648, 95% CI: 0.336-1.252, p=0.197). Similarly, odds of reoperation (OR:0.726, 95% CI:0.493-1.068, p=0.104) and complication rates were similar between the two groups (OR:1.299, 95% CI:0.536-3.149, p=0.563). Standardized mean difference (SMD) for the blood loss (SMD: 0.728, 95% CI:0.554-0.901, p=0.000) and operative (SMD:0.653, 95% CI: 0.479-0.826, p=0.000) differed significantly between the two groups. The indirect analysis showed similar fusion (Effect Size (ES)crossing: 0.892, 95% CI: 0.840-0.928 vs ES not crossing:0.894, 95% CI:0.849-0.926); reoperation rate (EScrossing:0.112, 95% CI:0.075-0.164 vs ES not crossing: 0.125, 95% CI: 0.071-0.211) and complication rates (EScrossing: 0.108, 95% CI: 0.074-0.154 vs ES not crossing:0.081, 95% CI: 0.040-0.156). CONCLUSIONS Our meta-analysis showed that fusion, complication and reoperation rates did not differ significantly between patients in whom multi-level posterior fusions ended in the cervical spine versus those of which was extended into the thoracic spine. The mean blood loss, operative time and length of stay were significantly lower in patients with caudal level as C7 or below, compared to their counterparts. These data suggest that, absent focal C7-T1 pathology, extension of long posterior cervical fusions into the thoracic spine may not be necessary. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.