Cervical Spondylotic Myelopathy: Does Surgical Approach Influence Postoperative Sagittal Alignment and Outcomes?

• Published in: Global Spine Journal Vol. 5; no. 1_suppl; p. s-0035-1554529
• Main Authors: Fehlings, Michael, Smith, Justin, Challier, Vincent, Shaffrey, Christopher, Kim, Han Jo, Arnold, Paul, Chapman, Jens, Protopsaltis, Themistocles, Lafage, Virginie, Liu, Shian, Lafage, Renaud, Schwab, Frank, Massicotte, Eric, Yoon, S. Tim, Ames, Christopher
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Los Angeles, CA SAGE Publications 01.05.2015
• ISSN: 2192-5682; 2192-5690
• DOI: 10.1055/s-0035-1554529

Introduction The effect of surgical approach on outcomes for cervical spondylotic myelopathy (CSM) is controversial. Fehlings et al showed that patients treated with anterior techniques tend to be younger, less impaired, and had more focal pathology. In this study, we compared outcomes of an anterior approach group (AAG) versus a posterior approach group (PAG) with a focus on the effect of sagittal alignment. Patients and Methods Post hoc analysis of a prospective, multicenter database of patients with CSM. A total of 117 patients met inclusion criteria, were nonrandomized to an AAG (n = 51) or PAG (n = 62), with postoperative static lateral radiographs, Nurick assessment, and health-related quality of life outcomes at 6 months and/or 1 year. The AAG underwent anterior decompression and fusion, PAG either laminoplasty or laminectomy with fusion. Sagittal regional and focal parameters were compared by multivariate regression. Results At baseline, the groups showed significant age difference (AAG 51 years, PAG 62 years, p < 0.001), rheumatological comorbidity (AAG 3%, PAG 19%, p = 0.011), and modified Japanese orthopaedic association (mJOA). The PAG had significantly more regional malalignment at baseline, but there were no focal alignment differences between the two. Surgical features were significantly different for greater than three levels treated (AAG 27%, PAG 97%, p < 0.001) and blood loss (AAG 152 mL, PAG 380 mL, p < 0.001). After surgery, both AAG and PAG improved significantly in mJOA and Nurick grade, however, there was no statistically significant difference in mJOA postoperatively. AAG had a significant decrease in SVA whereas the PAG had a significant increase in SVA. There were no relevant postoperative focal alignment differences. Conclusion The PAG had older patients with more disability. Even when age, baseline mJOA, and regional parameters were controlled, the PAG cohort still correlated with worse CGH_C7 SVA and TS–CL. It is interesting to note that the PAG had a lower mJOA than the AAG at baseline, they both improved and were not significantly different postoperatively. This suggests that both techniques relieve symptomatic disease, but patients in the posterior group may continue to progress in sagittal misalignment.