Asian Spine J.  2024 Feb;18(1):94-100. 10.31616/asj.2023.0090.

Significance of Facet Fluid Index in Anterior Cervical Degenerative Spondylolisthesis

• Lee Y
• Heard JC
• Lambrechts MJ
• Kern N
• Wiafe B
• Goodman P
• Mangan JJ
• Canseco JA
• Kurd MF
• Kaye ID
• Hilibrand AS
• Vaccaro AR
• Kepler CK
• Schroeder GD
• Rihn JA

• KMID: 2553042
• DOI: http://doi.org/10.31616/asj.2023.0090

Abstract

Study Design: Retrospective cohort study. Purpose: To correlate cervical facet fluid characteristics to radiographic spondylolisthesis, determine if facet fluid is associated with instability in cervical degenerative spondylolisthesis, and examine whether vertebral levels with certain facet fluid characteristics and spondylolisthesis are more likely to be operated on. Overview of Literature: The relationship between facet fluid and lumbar spondylolisthesis is well-documented; however, there is a paucity of literature investigating facet fluid in degenerative cervical spondylolisthesis.
Methods
Patients diagnosed with cervical degenerative spondylolisthesis were identified from a hospital’s medical records. Demographic and surgical characteristics were collected through a structured query language search and manual chart review. Radiographic measurements were made on preoperative MRIs for all vertebral levels diagnosed with spondylolisthesis and adjacent undiagnosed levels between C3 and C6. The facet fluid index was calculated by dividing the facet fluid measurement by the width of the facet. Bivariate analysis was conducted to compare facet characteristics based on radiographic spondylolisthesis and spondylolisthesis stability.
Results
We included 154 patients, for whom 149 levels were classified as having spondylolisthesis and 206 levels did not. The average facet fluid index was significantly higher in patients with spondylolisthesis (0.26±0.07 vs. 0.23±0.08, p <0.001). In addition, both fluid width and facet width were significantly larger in patients with spondylolisthesis (p <0.001 each). Cervical levels in the fusion construct demonstrated a greater facet fluid index and were more likely to have unstable spondylolisthesis than stable spondylolisthesis (p <0.001 each).
Conclusions
Facet fluid index is associated with cervical spondylolisthesis and an increased facet size and fluid width are associated with unstable spondylolisthesis. While cervical spondylolisthesis continues to be an inconclusive finding, vertebral levels with spondylolisthesis, especially the unstable ones, were more likely to be included in the fusion procedure than those without spondylolisthesis.

Keyword

Cervical spine; Cervical stenosis; Spondylolisthesis; Facet fluid