Relationship between orientation of lumbar facet and degenerative lumbar spondylolisthesis

English Keywords:Spondylolisthesis  Degeneration  Lumbar vertebrae  Facet joint

English Abstract:

  【Abstract】 Objective：To investigate the relationship between the orientation of lumbar facet and degenerative lumbar spondylolisthesis（DLS）.Method：From July 2008 to June 2010，60 patients（average age：55.6±8.8 years）suffering DLS at L4/5 were reviewed retrospectively，those with lumbar fracture and spondylolysis were excluded in this study；while 57 cases（average age：53.7±9.4 years） without DLS and low back pain were selected as control group.Both 2 groups received lumbar CT scanning，the displacement of L4 and sagittal diameter of L5 in DLS group were measured on CT scan，the degree of spondylolisthesis（Taillard index） was calculated；the orientation of facet at L3/4，L4/5 and L5/S1 of both groups was measured from CT image and compared. L4/5 facet joint degeneration was evaluated.According to Fujiwara standard in bone window，the degree of spondylolisthesis（Taillard index） of the L4/5 at different degenerative grade of facet joint was compared，and the correlation between L4/5 facet joint orientation and degree of spondylolisthesis（Taillard index） were ana?鄄lyzed.Result：All L4/5 spondylolisthesis in DLS group were gradeⅠ，with the average Taillard index of 0.1679±0.0365，the angle of the facet joint of L4/5 was less than control group（33.1°±12.2° vs 49.5°±11.4°，P<0.001），but no significant difference with respect to L3/4 and L5/S1 between both groups（36.1°±9.1° vs 38.6°±8.0°，48.5°±13.0° vs 51.9°±13.0° respectively，P＞0.05） were noted.In DLS group，no relationship between degree of spondylolisthesis（Taillard index）and the orientation of the L4/5 facet joint was noted（r=0.065，P＞0.05）.As for L4/5 facet joint degeneration in DLS group，there were 4 grade Ⅱ，23 grade Ⅲ and 33 grade Ⅳ，with the Taillard index of 0.1837±0.0418，0.1723±0.0370 and 0.1589±0.0343 respectively，which showed no significant difference among each grade（P＞0.05）.Conclusion：For DLS patient，the angle of facet joint at slipping level in section is less than the same section of patients without spondylolisthesis，but the relationship between facet joint angel and DLS remains unclear.