Lumbar Facet Joint Effusion on MRI as a Sign of Unstable Degenerative Spondylolisthesis

Abstract

Retrospective study. To examine whether the outcomes of decompression alone (D) or decompression with fusion (D&F) differed depending on the presence or absence of the facet effusion sign in degenerative spondylolisthesis. There is ongoing discussion as to whether D&F is superior to D in the surgical treatment of patients with lumbar degenerative spondylolisthesis (LDS) and symptoms of spinal or radicular claudication. Previous studies have shown that a positive facet joint effusion sign on magnetic resonance imaging correlates with the spontaneous reduction of slip when comparing upright and supine postures and might represent a sign of instability, guiding treatment decisions. One hundred sixty patients [age 69 (SD 10) y; 119 women, 41 men] with a diagnosis of LDS were identified retrospectively from our Spine Center Registry (linked to the Eurospine, Spine Society of Europe Spine Tango Registry). They were categorized based on the presence/absence of the facet effusion sign and the type of treatment received. Forty-four patients had effusion and underwent D; 76 effusion and D&F; 19 no effusion and D; and 21 no effusion and D&F. Before surgery and 3, 12, and 24 months after surgery, patients completed the multidimensional Core Outcome Measures Index questionnaire. At follow-up, they rated the global treatment outcomes (1-5 scale). Multiple regression analyses evaluated the factors influencing the outcomes. When age and sex was controlled for, there was no significant difference in outcomes dependent on the presence of the facet effusion sign and/or the treatment received (D vs. D&F). Although mindful of the limitations of this retrospective study, we conclude that the effusion sign alone does not seem to be an indication for adding fusion to decompression in the treatment of LDS. Hence, the presence of the facet effusion sign should not, in itself, deter the surgeon from performing decompression alone. However, the phenomenon should be investigated in larger samples of patients, ideally within a randomized trial.