Comparative analysis of the Impacts of 30-day Perioperative Complications on Patient-Reported Outcomes following Multilevel Anterior versus Posterior Cervical fusion

Introduction: Many studies have compared outcomes following anterior and posterior cervical fusion, yet the differences in the impacts of perioperative complications on outcomes has not been well studied. To that effect, this study aims to assess the differences in the effects of 30-day perioperative complication on patient reported outcomes (PRO) after anterior versus posterior cervical fusion.

Methods: Adult patients who underwent anterior or posterior cervical fusion at 3 or more levels between 2014 and 2020 were analyzed. Each group was sub-divided based on the occurrence and severity of perioperative complication: no complication versus minor versus major complication. The study primarily compared PRO scores and minimal clinically important differences (MCID) within and between the groups.

Results: One hundred and forty-six anterior (no complication = 102, minor = 36, major = 8) and 55 posterior (no complication = 36, minor = 13, major = 6) cervical fusion cases were analyzed. Within the anterior or posterior group, there were no significant differences in the PRO changes or proportions of patients achieving MCID. In comparing the anterior to posterior group, anterior patients without complications had better improvement in 3-month NDI (Coefficient 11.2 p=0.019) with higher odds of achieving MCIDs for mJOA at 3 months (Odd ratio 2.0 p=0.039). Otherwise, there were no significant differences in the PRO change or proportions of patients achieving MCID in subsets of anterior or posterior patients with minor or major complications. Furthermore, patients with major complications, regardless of their surgical approach, exhibited higher early readmission rate. Major complications were also associated with both lengthy or increased rate of intensive care unit stay after posterior fusion than anterior fusion.

Conclusion : This study suggests that the severity of perioperative complication following anterior or posterior cervical fusion did not predict changes in PROs or the achievement of MCID in the anterior or posterior group. Also, PRO may not fully differentiate the full extent of the impact of perioperative complication following anterior versus posterior cervical fusion. Otherwise, in subsets of patients without complication, anterior compared to posterior patients had improved NDI scores at 3 months with significant proportion of patients achieving MCID for mJOA at 3 months.