Abstract
Introduction
Surgical manipulations at C7 level present the most difficulty during a posterior cervicothoracic fusion where instrumentation across the cervicothoracic junction is required. There is increased risk of vascular injury, neurological injury, and possibility of postoperative instability because of the surgical complications at this site. Placement of C7 instrumentation also poses additional difficulty during rod placement. Vertebral artery (when present) and C8 nerve roots are the most important structures susceptible to the surgical injury at C7 level. Our clinical observations suggested that skipping instrumentation at C7 in a multiple level posterior cervicothoracic fusion will result in minimal intraoperative complications, decreased surgical time, while still maintaining fixation, sagittal balance parameters, and successful rates of fusion.
Methods
This was a retrospective chart review of 49 patients (mean age: 62 years; range: 45–87 years) undergoing multilevel posterior cervicothoracic fusion between November 2010 and October 2014. Of the 49 patients, 42 had no screws placed at C7 level and 7 patients had instrumentation done at C7 and served as a control group. Assessment of the safety and efficacy of skipping C7 instrumentation were based on intraoperative complications, operative time, estimated blood loss (EBL), and radiographic evidence of fusion and spine stability.
Results
There were no intraoperative complications though two patients (one skipped and one not skipped) required extended time under anesthesia because of the difficulty in patient positioning and intubation. Skipping C7 resulted in reduced average operative time compared with those patients instrumented at C7 (203 vs. 171 minutes, respectively). In addition, skipping C7 reduced average EBL compared with patients instrumented at C7 (531 vs. 445 mL, respectively). In addition, patients skipped at C7 maintained sagittal balance with fusion rates identical to control patients at follow-up with a very low incidence of pseudarthrosis.
Conclusion
Skipping instrumentation at C7 in a multilevel posterior cervicothoracic fusion demonstrates lower EBL and faster operative times compared with performing instrumentation at the C7 level. In addition, in a postoperative assessment of patients undergoing posterior cervicothoracic fusion identical rates of fusion were achieved. Serious negative outcomes of skipping C7 were not found in this retrospective study. The results of this study point to the clinical benefits of skipping C7 to minimize surgical risk and complications in patients undergoing posterior cervical fusion across the cervicothoracic junction.