The Relationship Between Sagittal,Horizontaland Degenerative Lumbar Anterior Spondylolisthesis In Articular Process Joint Direction

Background : with the aggravation of the elderly society,the enhancement of people’s health consciousness and the improvement of examination means,lumbar degenerative spondylolisthesis is increasing,and the related research is increasing.it is gradually recognized that the degeneration of articular facet joint is closely related to LDS,FJ degeneration includes calcified hyperplasia,articular facet direction change,subluxation,among these changes,facet joint orientation change is more closely related to the LDS.The articular surface of the articular process is a three-dimensional space from the upper layer to the lower layer,with uneven direction and curved surface structure.Therefore,it is difficult to elaborate the three-dimensional spatial relation in detail.Clinically,some of the elderly patients with common low back pain have lumbar spondylolisthesis while others do not,whether the causes of these two different clinical outcomes are related to FJO changes.Objective: To explore whether sagittal and horizontal FJO of the same anatomical site can be the cause of anterior spondylolisthesis of degenerative lumbar 4 vertebrae.Methods: From September 2017 to December 2019,30 patients with lumbar 4 degenerative anterior lumbar spondylolisthesis in our hospital were collected as case group,including 10 males and 20 females,with an average age of 64.00±2.80 years.Control group selected 30 outpatients,9males and 21 females in the same period,with an average age of64.00±3.63 years.Multi-level reconstruction technique(multiplanar reformation MPR)with 64-row spiral CT was used to reconstruct FJtwo-dimensional reconstruction on three cross sections: parallel upper end plate,end plate and lower end plate.The angle between FJO and sagittal plane of vertebral body was measured as articular joint angle(facet joint angle FJA),which was recorded as upper FJA、 middle FJA、 lower FJA.At the same time,the degree of degeneration FJ three cross-sectional levels was quantitatively evaluated by grading method: grade 0,normal;grade 1,mild degeneration;grade 2,moderate degeneration;grade 3,severe degeneration.a two-dimensional reconstruction of the articular process joint was performed on the lateral edge of the lumbar 4 vertebral canal parallel to the sagittal plane of the vertebral body.the angle between the axis of the lumbar 4 pedicle and the L4-5 articular process joint space was measured as the pedicle-articular process angle.Results :1,the p values were <0.05,and the difference was statistically significant in the FJA comparison between the slip group and the non-slip group.The FJ A difference angle between the two groups was compared,and the difference angle between the upper-middle and upper-lower levels was P <0.05,the difference was statistically significant,while the difference angle between the middle-lower FJ A was P <0.05,the difference was not statistically significant.2.angle of pedicle-articular process between the two groups P <0.05,the difference was statistically significant.There was no significant difference between the two groups 3.the asymmetry between the angle of pedicle and articular process P >0.05.Conclusion:1.In the process of degeneration,the degree of degeneration is not completely consistent in the upper,middle and lower three cross-sections.2.relative to the control group,the FJA of L4-5 segments in the spondylolisthesis group was significantly less than 45° in all three levels,indicating that there was obvious sagittal FJO in the spondylolisthesis segment,and greater than 45° in all the L4-5 segments in the non-sliding group,indicating that the segment in the non-sliding group was biased towards the coronal position;3.Compared with the two groups,the angle of arcuate root-articular process was larger than that of the non-sliding group,which indicated that FJO was more inclined to level in sagittal plane.4.On the cross section,the asymmetry of left and right FJA has no pre-judgment value for the occurrence of LDS.5.sagittal,horizontal FJO are more likely to produce anterior slippage,and coronal FJO are less likely to produce anterior slippage.Therefore,it is suggested that sagittalization and horizontalization of FJO may have a certain etiological significance for the occurrence of LDS,which can be used as relevant predictors of LDS occurrence.