A systematic literature review to identify the best method for a single level anterior cervical interbody fusion

The goal of this systematic literature review was to determine, for patients with degenerative disc disease, which method of single-level anterior cervical interbody fusion using the anterior approach gives the best clinical and radiological outcome. The number of new techniques for obtaining a solid fusion has increased rapidly, but the rationale for choosing between different techniques is unclear. Randomised comparative studies on anterior cervical interbody fusions were identified in a sensitive Medline, Cochrane and Current Contents database search. Two independent reviewers evaluated the articles that met the selection criteria, using a checklist. The search yielded eight randomised, controlled trials for the systematic literature review. Three of these studies were judged to be of sufficient quality with regard to methodology and the information provided. In the three articles, five different treatment methods were investigated, four of which were interbody fusions. Fusion rates varied between 28% for an allograft method and 63% for a discectomy-alone method. In one study, kyphosis varied from 40% to 62% between treatments. Good clinical outcome (disability, pain and symptoms) ratings varied from 66% to 82%. A meta-analysis to determine the best method for an anterior interbody fusion could not be performed due to the heterogeneity of the methods reported and because no standard outcome parameter was used. From this systematic literature review, a gold standard for the treatment of degenerative disc disease could not be identified.