Comparison of anterior approach versus posterior approach for the treatment of multilevel cervical spondylotic myelopathy

The purpose of this study is to evaluate the clinical outcomes, complications, and surgical trauma between anterior and posterior approaches for the treatment of multilevel cervical spondylotic myelopathy (CSM). Systematic review and meta-analysis. Randomized controlled trials or non-randomized controlled trials published up to November 2014 that compared the clinical effectiveness of anterior and posterior surgical approaches for the treatment of multilevel CSM were acquired by a comprehensive search in four electronic databases (PubMed, EMBASE, Cochrane Controlled Trial Register and MEDLINE). Exclusion criteria were non-controlled studies, combined anterior and posterior surgery and cervical myelopathy caused by ossification of the posterior longitudinal ligament. The main end points included: recovery rate; Japanese Orthopedic Association (JOA) score; complication rate; reoperation rate; blood loss; operation time and length of stay. A total of ten studies were included in the meta-analysis; none of which were randomized controlled trials. All of the selected studies were of high quality as indicated by the Newcastle–Ottawa scale. In six studies involving 467 patients, there was no significant difference in the preoperative JOA score between the anterior surgery group and the posterior group [P > 0.05, WMD −0.00 (−0.50, 0.50)]. In four studies involving 268 patients, the postoperative JOA score was significantly higher in the anterior surgery group compared with the posterior surgery group [P   0.05, WMD 2.73 (−8.69, 14.15)]. In nine studies involving 804 patients, the postoperative complication rate was significantly higher in the anterior surgery group compared with the posterior surgery group [P = 0.009, OR 1.65 (1.13, 2.39)]. In five studies involving 294 patients, the reoperation rate was significantly higher in the anterior surgery group compared with the posterior surgery group [P = 0.0001, OR 8.67 (2.85, 26.34)]. In the four studies involving 252 patients, the intraoperative blood loss and operation time was significantly higher in the anterior surgery group compared with the posterior surgery group [P < 0.05, WMD −40.25 (−76.96, −3.53) and P < 0.00001, WMD 61.3 (52.33, 70.28)]. In the three studies involving 192 patients, the length of stay was significantly lower in the anterior surgery group compared with the posterior surgery group [P < 0.00001, WMD −1.07 (−2.23, −1.17)]. In summary, our meta-analysis suggested that a definitive conclusion could not be reached regarding which surgical approach is more effective for the treatment of multilevel CSM. Although anterior approach was associated with better postoperative neural function than posterior approach in the treatment of multilevel CSM, there was no apparent difference in the neural function recovery rate between the two approaches. Higher rates of surgery-related complication and reoperation should be taken into consideration when anterior approach is used for patients with multilevel CSM.