Association Between Irregular Alteration of Facet Orientation and Degenerative Lumbar Spondylolisthesis

Numerous studies have reported that irregular alteration of facet orientation (IAFO) is associated with lumbar disc herniation (LDH) in adolescents. The present study investigated the association between IAFO and degenerative lumbar spondylolisthesis (DLS) at the L4-5 segment.

Forty-two adults with DLS were enrolled in this study. Facet angles were measured in the bone window of the computed tomography scan. Large-small-large (LSL) was defined as a type of IAFO that includes the angle of facet joints at L4-5, which is smaller than that in L3-4 and L5-S1 segments. Fifty subjects with LDH at L4-5 served as controls. Data were analyzed using logistic regression analysis.

In the 42 patients and 50 controls, the facet angle was measured at 276 levers from L3-4 to L5-S1. The mean included angles of L3-4, L4-5, and L5-S1 were 71.5 ± 19.97°, 51.79 ± 21.43°, and 102.89 ± 20.37°, respectively, in the DLS group and 77.48 ± 17.24°, 91.00 ± 17.24, and 102.94 ± 19.75°, respectively, in the control group. LSL was detected in 38 of 42 subjects (90.5%) in the DLS group, compared with 9 of 50 (18.0%) in the controls. The sagittal orientation facet joint in L4-5 was associated with DLS (odds ratio [OR], 26.24; 95% confidence interval [CI], 13.30-155.35; P = 0.000). The facet in L3-4 with a more coronal orientation than that in L4-5 was also correlated with DLS (OR, 33.68; 95% CI, 9.86-115.06; P = 0.000). There was no correlation between the facet in L5-S1 and DLS in L4-5 (P = 0.999), but there was a strong relationship between LSL in L3-5 and DLS in L4-5 (OR, 43.278; 95% CI, 12.303-152.232; P = 0.000).

The data presented here demonstrate that LSL, which is an irregular alteration of facet joint orientation, is associated with the degenerative lumbar spondylolisthesis at L4-5.