Should Multilevel Posterior Cervical Fusions Involving C7 Cross the Cervicothoracic Junction? A Systematic Review and...

Current literature remains inconclusive as to whether multilevel posterior cervical fusions (PCFs) involving the C7 vertebra should cross the cervicothoracic junction (CTJ). The objective of this systematic review was to assess the differences in clinical outcomes, fusion, and reoperation rates, between patients undergoing multilevel PCFs ending at C7 and those undergoing PCF crossing the CTJ.

A systematic review of literature from 4 databases on crossing the CTJ was conducted. Inclusion criteria consisted of 1) patients undergoing multilevel PCF or combined anterior and PCF involving C7, 2) diagnosis for surgery being degenerative disk or deformity.

Six studies consisting of 530 patients were included in this review. Two were 1-arm studies and 4 were comparative studies. There were 305 patients (58%) in the noncrossing group and 225 patients (42%) in the crossing group. Among the 3 comparative studies that recorded fusion rate, patients in the crossing group were more likely to achieve fusion (odds ratio, 2.75; 95% confidence interval, 1.61-4.09; P < 0.001) and were less likely to undergo a reoperation (odds ratio, 0.42; 95% confidence interval, 0.25-0.73; P = 0.002) compared with patients in the noncrossing group. In our indirect analyses, fusion rate and reoperation rate were comparable between the 2 groups (P = 0.689 and P = 0.714, respectively).

Our results indicate that based on current evidence, multilevel PCFs that cross the CTJ may have higher fusion rates and lower reoperation rates compared with fusions that stop at C7. These results are important to assist the surgeon in decision making regarding the lower instrumented level when performing a multilevel PCF.