The relationship of sagittal facet joint angle and degenerative lumbar spondylolisthesis

Abstract

Objective To explore the relationship between sagittal facet joint angle(FJA)and degenerative lumbar spondylolisthesis (DLS). Methods Retrospective study. Eighty-nine patients with single-segment L4/5 DLS in the Department of Orthopedics, Xuanwu Hospital, Capital Medical University from January 2010 to May 2018 were enrolled as the DLS group. According to age and course, they were divided into A1 and B1 subgroups, 44 patients in A1 group (14 males and 30 females), aged<65 years old; 45 patients in B1 group (17 males and 28 females), aged ≥65 years old. In the control group, 100 outpatients with lumbago and leg pain at the same period were matched with DLS group in sex and age, but no lumbar spondylolisthesis was found. According to the age and course of disease, 54 cases (18 males and 36 females) were divided into A2 and B2 subgroups, and 46 cases (15 males and 31 females) were divided into B2 subgroups. FJA of L4/5 and L3/4 were measured by soft tissue window of lumbar CT, and the differences of FJA, facet joint asymmetry (FT) and facet joint degeneration grading were analyzed by SPSS 22.0. Results In DLS group, FJA of L3/4 in A1 group and B1 group were 54.73°±7.26° and 56.60°±6.94°, respectively. There was no significant difference (P>0.05). FJA of L4/5 in A1 group and B1 group were 58.43°±10.41° and 63.28°±6.56°, respectively. There was significant difference (P 0.05). FJA of L3/4 and L4/5 between the two groups were compared, the differences were statistically significant (all P values 0.05). There was significant difference in the L4/5 between the DLS group and the control group (P 0.05). In L4/5 and L3/4, the degree of degeneration of FJ in DLS group was higher than that in control group, while that in B1 group was higher than that in A1 group (all P values 0.05). Conclusions DLS patients have a more sagittal FJA, which may be the result of secondary remodeling in the course of disease development. Key words: Spondylolysis; Lumbar vertebrae; Facet joint angle; Facet tropism; Facet joint degeneration