Clinical Study About The Association Of Facet Tropism And Orientation With Prolapsed Lumbar Disc Herniation In Young Patients

Objective:The correlation between facet tropism(FT)and prolapsed subtype of lumbar intervertebral disc herniation(PSLDH)in young patients was investigated by comparing the lumbar FT between young patients with PSLDH and young people without intervertebral disc herniation(LDH).By observing the direction of prolapsed nucleus pulposus and facet joint orientation(FJO)of the prolapsed side in PSLDH patients,the relationship between FJO and the direction of prolapsed nucleus pulposus in young patients was discussed.Methods:From January 2013 to December 2018,401 PSLDH patients who underwent surgical treatment in our hospital were selected as case group according to inclusion and exclusion criteria.At the same time,267 young people without LDH were selected as the control group according to inclusion and exclusion criteria.All subjects received CT and MRI examinations,and FJA was measured on the CT images.FJA was measured on both sides of the prolapsed segment of the PSLDH group and on both sides of the L4/5 and L5/S1 segments of the control group.In bilateral FJA,the side with large angle is coronal FJA,while the side with small angle is sagittal FJA.In this study,facet tropism was defined as the difference between the angle of the right and left facet joint greater than 10°,and the number of FT in the PSLDH group and the control group was counted and compared to determine whether FT was correlated with the occurrence of PSLDH in young people.In addition,the direction of prolapsed nucleus pulposus and FJO of the prolapsed side in the PSLDH group were calculated,and then the correlation between them was investigated.SPSS software was used to analyze the data.Results:(1)Comparison of age and gender between the two groups: the age of subjects in the PSLDH group and the control group were 27.5±5.1 years old and 28.7±4.4 years old,respectively.PSLDH group included 245 males and156 females;and the control group included 166 males and 101 females.There was no significant difference in age and sex between the two groups(P>0.05).(2)Comparison of bilateral FJA differences between the two groups: the bilateral FJA differences of the PSLDH group and the control group were6.7°±5.0° and 4.7°±3.8°,respectively.There was statistically significant difference between the two groups(P<0.05).(3)Comparison of FT distribution in PSLDH group and control group: PSLDH group has a total of 401 segments,of which 86(21.4%)presented FT.There were 534 segments in the control group,of which 53(9.9%)presented FT.There was a statistically significant difference in the probability of FT cases between the PSLDH group and the control group(P<0.05).(4)The relationship between the direction of prolapsed nucleus pulposus and facet joint orientation(FJO)of the prolapsed side in PSLDH group: there were 401 prolapsed segments in the PSLDH group,among which 228 segments with prolapsed nucleus pulposus toward the left side and 173 segments toward the right side.Of the 228 left prolapsed segments,FJO of the prolapsed side for 118 segments is coronal,and for 110 segments is sagittal.Of the 173 right prolapsed segments,FJO of the prolapsed side for 88 segments is coronal,and for 85 segments is sagittal.In the PSLDH group,the FJO of 206 segments was coronary on the prolapse side,and the FJO of 195 segments was sagittal on the prolapse side,there was no significant difference between the sagittal orientation and the coronal orientation of facet joint on the prolapse side(P=0.583).(5)The relationship between the direction of prolapsed nucleus pulposus and facet joint orientation(FJO)of the prolapsed side at the FT segments in PSLDH group: there were 86 prolapsed segments with FT in the PSLDH group,among which 50 segments with prolapsed nucleus pulposus toward the left side and 36 segments toward the right side.Of the 50 left prolapsed segments,FJO of the prolapsed side for 25 segments is coronal,and for 25 segments is sagittal.Of the 36 right prolapsed segments,FJO of the prolapsed side for19 segments is coronal,and for 17 segments is sagittal.In the FT segments of PSLDH group,the FJO of 44 segments was coronary on the prolapse side,and the FJO of 42 segments was sagittal on the prolapse side,there was no significant difference between the sagittal orientation and the coronal orientation of facet joint on the prolapse side(P=0.829).Conclusion:FT is associated with PSLDH at both L4/5 and L5/S1 segments in young patients,and FT may be a risk factor for PSLDH in young patients.However,there was no relationship between FJO and the direction of prolapsed nucleus pulposus in young patients.