Morphologic Changes And Its Significance Of The Lumber Facet Joints And Intervertebral Foramina For Lumbar Degenerative Scoliosis

Objective: To measure the lumbar Cobb angle, facet joints angle and foraminal size by images of lumber degenerative scoliosis, and to explore its morphological Characteristics and pathogenesis.Methods: 69 cases with lumber degenerative scoliosis(30 males and 39 females, aged 50 to 78 years, average 63.5 years old )and 68 normal controls( 32 male and 36 female, aged 50 to 76 years, average 59.6 years old) with did not have spinal deformity in this study. Measuring the lumbar Cobb angle in X-ray image.Successive CT lumbar vertebras scanning of all subjects were obtained,the orientation of lumbar facet joints and lumbar vertebras foraminal of all participants were measured with the software of PACS Client. In the control group, bilateral facet joints and intervertebral foramen were compared using paired-t test. In LDS group,the concave and convex side size of facet joints and intervertebral foramen were analyzed using paired-t test . linear correlations between the image index of the scoliosis group and clinical parameters,were calculated using Pearson correlation coefficients.RESULTS: The cobb angle of lumber degenerative scoliosis was 10 ~ 39.8°, an average of 18.21°±8.89°, In control group,no difference were found in bilateral orientation of lumbar facet joints(P >0.05).In LDS group,the orientation of lumbar facet joints in the concave side Was lager than that in the convex side(P<0.05).The lumbar foraminal longitudinal diameter and sagittal diameter of LDS group were lower than control group(P<0.05). In LDS group,the lumbar intervertebral foramen sagittal diameter of concave side is smaller than that in the convex side , there were significant differences between the two groups (P <0.05),while there were no significant differences between the concave side of foraminal longitudinal diameter and the convex side. In control group,no difference were found in bilateral lumbar intervertebral foramen(P >0.05) .Conclusion: 1. Our findings suggested that the lumbar facet joints on both sides of lumber degenerative scoliosis are asymmetry ,and the facet joint angle in the concave side is largeer than that in the convex side.2. The lumbar intervertebral foramina longitudinal diameter and sagittal diameter of lumber degenerative scoliosis are all narrow,and the lumbar intervertebral foramina sagittal diameter in the concave side was significantly narrower than that in the convex side.3.The main reasons that the lumbar intervertebral foramina sagittal diameter became narrow in the concave side of lumber degenerative scoliosis was the lumbar facet joints angel in the concave side increase leading to degenerative proliferation of facet joint4. Our study suggests that the lumbar facet joints with asymmetry on both sides is an important pathogenesis for lumber degenerative scoliosis.