Facet Sagittal Orientation Possible Role in the Pathology of Degenerative Lumbar Spinal Stenosis

Study Design. A retrospective case-control study. Objective. This study aimed to elucidate the association between facet joint orientation and degenerative lumbar spinal stenosis (DLSS). Summary of Background Data. Many studies have demonstrated the relationship between sagittal facet orientation and degenerative lumbar spondylolisthesis. However, the associations between facet orientation and DLSS have rarely been studied. Methods. Ninety-one age-matched and sex-matched patients with DLSS (LSS group) and 91 control participants were consecutively enrolled. Their lumbar facet angles and the dural sac cross-sectional area at L2-L3, L3-L4, L4-L5, and L5-S1 were measured using axial magnetic resonance imaging. The intersection angle of the midsagittal line of the vertebra to the facet line represents the orientation of the facet joint. Results. The facet angles on the left side or right side of the LSS group were significantly smaller than the respective ones of the control group. Outcomes of the groups revealed significantly and consistently increasing facet angles from L2-L3 to L5-S1. The dural sac cross-sectional area of the LSS group had significantly smaller measurements values than that of the control group at L2-L3, L3-L4, L4-L5, and L5-S1. Conclusion. Sagittalization of lumbar facet joints was considered to be a risk factor for DLSS and may play a role in the pathology of DLSS.