Systematic review of cohort studies comparing surgical treatment for multilevel ossification of posterior longitudinal ligament: anterior vs posterior approach.

There have been no standards or guidelines for the treatment of ossification of posterior longitudinal ligament, especially multilevel ossification of posterior longitudinal ligament. The purpose of this study was to compare results of major surgical treatment for multilevel ossification of posterior longitudinal ligament. Databases including MEDLINE, EMBASE, the Cochrane library, and bibliographies of identified and review articles were searched to find randomized, controlled trials or retrospective cohort studies comparing anterior and posterior approach from 1980 to December 2010. Approximately 1375 articles were found initially, 92 abstracts were screened, 23 articles were retrieved in full; 3 studies were included in the review. No randomized, controlled studies were identified. Because all the studies included in this study are cohort studies with disparity of surgical interventions, heterogeneity of outcome measures and different qualities, we were unable to perform a meta-analysis. All comparison studies are retrospective cohort studies, comparing surgical outcomes of anterior approach (corpectomy and fusion) with that of posterior approach (laminoplasty or laminectomy) for the treatment of multilevel ossification of posterior longitudinal ligament in the cervical spine. A systematic review of retrospective cohort studies was performed to determine which surgical treatment is the most effective in patients with multilevel ossification of posterior longitudinal ligament. Definitive conclusions regarding the surgical treatment of multilevel ossification of posterior longitudinal ligament could not be made in this article. Multilevel corpectomy and fusion are more technical and have a significantly higher rate of cerebrospinal fluid leakage and graft, instrumentation related complications. A well-designed, prospective, randomized controlled, multicenter trial is needed.