Efficacy and Safety of Surgical Interventions for Treating Multilevel Cervical Spondylotic Myelopathy via Anterior Approach: A Network Meta-Analysis

Abstract

Background: Anterior cervical discectomy, with or without interbody fusion, is a common technique to treat cervical spondylotic myelopathy (CSM). To date, controversy still exists among spine surgeons regarding the anterior surgical approach to be used for the treatment of multilevel CSM. Objectives: To evaluate the effectiveness and safety of anterior cervical discectomy and fusion (ACDF), anterior cervical corpectomy and fusion (ACCF), cervical total disc replacement (CTDR), and hybrid surgery (HS) in the treatment of multilevel CSM. Study Design: Network meta-analysis (NMA) of randomized or nonrandomized controlled studies for the treatment of multilevel CSM. Methods: The databases such as PubMed, CENTRAL, and EMBASE were used to search and identify the clinical trials involving the evaluations for the treatment of multilevel CSM. The Newcastle-Ottawa Scale was used for the assessment of methodological qualities, whereas the Cochrane Collaboration tool was used for assessing the risk of bias. Outcome assessments included duration of surgery, Neck Disability Index (NDI) scores, and complications. Odds ratio was used to express dichotomous outcomes, whereas mean difference with a 95% confidence interval was used to express continuous outcomes. Results: Sixteen relevant studies were identified, and 1,639 patients were included in this analysis. CTDR demonstrated a prominently decreased NDI score and total incidence of complications compared with ACDF, ACCF, and HS. In addition, ACDF resulted in shorter operation times compared with ACCF, CTDR, and HS. The ranked order of NDI score improvement in decreasing order was: CTDR, HS, ACDF, followed by ACCF. The rank order for reduction in operation time increased progressively from ACDF, HS, ACCF to CTDR. The total incidence of complications also showed a decreasing trend in the decreasing order— CTDR, ACDF, HS, ACCF, and finally CTDR with the lowest complication rate. Limitations: The limitations of this NMA include inconformity of the follow-up times and surgical skill, and implants of different treatment centers vary. Conclusions: The analysis of this study has shown that the best method for improvement of functional outcome and reduction in total incidence of complications for multilevel CSM is CTDR. Key words: Multilevel cervical spondylotic myelopathy, anterior cervical discectomy and fusion, anterior cervical corpectomy and fusion, cervical total disc replacement, hybrid surgery, effectiveness, safety, network meta-analysis