The best surgical approach to treating cervical spondylotic myelopathy (CSM) remains controversial, with proponents of anterior, posterior and combined antero-posterior(AP) approaches. In an attempt to address this question, Dr. Wen and his colleagues from China reviewed 255 CSM patients treated at 3 centers over 10 years. While they did not clearly delineate the surgical techniques employed—and one can assume a variety were used given multicenter involvement over a long period of time—they evaluated CSM patients treated with either an anterior, posterior, or AP approach. Not surprisingly, the groups had important baseline differences, including more pre-operative lordosis in the posterior group and more comorbidities in the AP group. They reported a significantly greater improvement in JOA scores for the AP group (this group improved about 1.2 points more than the anterior or posterior groups), though AP surgery was also associated with longer operative time, greater blood loss, higher complication rate compared to anterior only surgery, and greater cost. The AP group also had the lowest rate of revision. Not surprisingly, the anterior and AP groups had an improvement in lordosis following surgery, while the posterior only group actually lost lordosis post-operatively. Based on these findings, the authors concluded that AP surgery might lead to the best neurological outcomes.
While this paper is a nice review of a large number of patients, given the heterogeneity of the patients included, it is hard to draw conclusions that can be applied to an individual patient. There has not been a Level 1 study comparing surgical approaches to CSM, though some recent data suggest that anterior surgery may lead to more consistent improvement versus laminoplasty.1 Given the variability in pathology that can be associated with CSM (i.e. number of levels involved, location of compression, lordosis vs. kyphosis) as well as the many surgical options available (i.e. ACDF, corpectomy, laminectomy, laminoplasty, laminectomy + fusion), it is unlikely that a high-quality RCT could be performed to definitively determine the best surgical approach. In an ideal world, we would perform RCTs for each patient subgroup and compare a wide variety of treatment options for each one, but it is unrealistic to think that this can be accomplished. As such, observational studies such as the current study will probably be the best we can do to help inform our surgical decision making. To be the most helpful, data will need to be recorded prospectively, and a large number of patients will be needed in order to have sufficient numbers in the important subgroups defined by factors such as number of levels involved and baseline sagittal alignment. The current literature on this topic provides surgeons with some general principles to follow when determining the surgical approach for CSM, but they still have to rely on good clinical judgment to determine what technique will likely lead to the best outcome for an individual patient in their hands.
Please read Dr. Wen’s article and accompanying commentary. Does this paper change your surgical approach to CSM? Let us know by leaving a comment on The Spine Blog.
Adam Pearson, MD, MS
Associate Web Editor
1. Hirai T, Okawa A, Arai Y, et al. Middle-term results of a prospective comparative study of anterior decompression with fusion and posterior decompression with laminoplasty for the treatment of cervical spondylotic myelopathy. Spine 2011;36:1940-7.