Luke Jouppi: No financial relationships to disclose
Introduction: Cervical stenosis is commonly treated with anterior cervical discectomy and fusion (ACDF) performed through a Smith-Robinson approach. Recently, facet fusion achieved with implantable devices from a posterior approach has been described as an alternative. To our knowledge, no anatomic studies have been performed comparing the combined surface area of the facet joints to the surface area of the intervertebral space. This study aimed to evaluate the cervical facet joints versus the interbody spaces and provide a better understanding of the potential surface area for fusion surgery.
Methods: We performed a cross-sectional retrospective review using cervical spine CT scans conducted from 2014-2017. Using our institution’s imaging software, we measured the area within the intervertebral space and the facet joints bilaterally. Surface areas for each intervertebral space were compared using a paired t-test to the cumulative surface area of the facet joints calculated at each level.
Results: Two-hundred twelve patients (120 male, 92 female) were eligible for the analysis based on our inclusion and exclusion criteria. The mean age was 33 years (range 18-55). The mean BMI was 29 (range 19-58). In each of the comparisons, the combined intra-facet joint surface area (IFSA) was significantly greater than the intervertebral surface area (IVSA) of the corresponding interbody space.
Conclusion : Our study found that the surface area between the IFSA is two to three times greater than the IVSA. This study may help establish an anatomic basis for comparable fusion results between the traditional intervertebral space method and an intra-facet joint fusion.