Correlation Between Spine-pelvic Sagittal Parameters And Clinical Outcome With Postoperative Low Back Pain After Lumbar Fusion

OBJECTIVE: To investigate the relationship between spinal-pelvis parameters and the changes of parameters before and after operation in patients with lumbar degenerative disease undergoing lumbar fusion operation,and the effect of surgical changes on postoperative chronic low back pain.Analyzing whether the changes of spinal pelvic parameters can help predict the curative effect and the occurrence of postoperative chronic low back pain,provide an objective sagittal balance index for the development of surgical treatment plan,and improve the postoperative satisfaction rate of lumbar degenerative diseases.METHODS: We retrospectively analyzed 61 patients with lumbar degenerative diseases who met the inclusion criteria and exclusion criteria in the Department of Spinal Surgery of Tianjin union medical center.The spinal-pelvic sagittal parameters(PT?PI?SS and LL)were measured on the lateral radiographs of the lumbar spine.The ODI index was used to evaluate the lumbar dysfunction of patients,and the VAS score was used to assess the degree of lumbar pain in both patients.Both of them can reflect clinical symptoms and surgical efficacy.All patients were evaluated at the last follow-up according to the NIH chronic low back pain evaluation criteria.The postoperative chronic low back pain or low back pain was compared with group A(n=34)and Group B(n=27).The changes of spinal pelvic parameters and surgical outcomes were compared before and after the operation.Analyse the correlation between spinal-pelvis parameters and the changes of the spinal-pelvic parameters and operation recovery.The analysis between the two groups was conducted by low back pain standard,analysed the differences in pelvic parameters and surgical outcomes.For patients with chronic low back pain after surgery,the differences in VAS scores and ODI indices between the two groups were compared according to the lumbar pelvis matching value(?PI-LL?).RESULTS: The PT at the last follow-up was lower than that before surgery,the difference was statistically significant(P=0.000).The SS at the last follow-up was significantly higher than that before surgery(P=0.037).The last follow-up LL increased compared with preoperatively,the difference was statistically significant(P=0.000).The last follow-up PI was less significant changes than before surgery,the difference was not statistically significant(P=0.084),that is,PI was a fixed parameter.There was no statistical difference in LLI index between the two groups before and after the last follow-up.The patients' last follow-up ODI index was significantly lower than the preoperative,the difference was statistically significant(P=0.000),the VAS score at the last follow-up was significantly lower than that before surgery,the difference was statistically significant(P=0.000).Before the operation,the lateral radiographs of the lumbar spine were PI and PT(r=0.614),SS(r=0.603)and LL(r=0.444)had positive correlation,SS had positive correlation with LL(r=0.801),and PT had no significant correlation with LL and SS.At the last follow-up of lumbar lateral radiographs,PI and PT(r=0.620),SS(r=0.604)and LL(r=0.448)have positive correlation,SS has positive correlation with LL(r=0.725),PT and LL,SS has no significant correlation.The VAS scores of patients at the last follow-up were negatively correlated with LLC(P=0.000)and LLI(P=0.001).The VAS score at the last follow-up patients has a positive correlation with ?PI-LL?(P=0.001);the ODI index of patients at the last follow-up was negatively correlated with LLC(P=0.015)and LLI(P=0.023).The ODI index of patients at the last follow-up was positively correlated with ?PI-LL?(P=0.031).Patients were divided into group A group and group B according to whether there was chronic low back pain after operation,including 34 cases in group A and 27 cases in group B.There were no significant differences in PT,PI,SS,LL,?PI-LL? and LLI(P>0.05).There was significant difference in preoperative VAS scores(P=0.000).There was no significant difference in preoperative ODI index between the two groups(P>0.05).Compared with the spinal-pelvic parameters in the last follow-up of the two groups: the PT in the A group was lower than that in the B group(P=0.001),the SS in the A group was greater than that in the B group(P=0.005),the ?PI-LL? in the A group was lower than that in the B group(P=0.040),the LLC in the A group was greater than that in the B group(P=0.006),the differences was statistically significant;there was no significant difference in PI between the two groups at the last follow-up(P>0.05).The ODI index of group A was lower than that of group B at the last follow-up,the difference was statistically significant(P=0.006).The VAS score of group A waslower than that of group B at the last follow-up,the difference was statistically significant(P=0.001).For the B group: the final follow-up VAS score was positively correlated with PT(P=0.020),PI(P=0.036),and ?PI-LL?(P=0.034).There was a negative correlation with LLC(P=0.014)and LLI(P=0.015),and no significant correlation with SS and LL(P>0.05).The last follow-up ODI of patients with chronic low back pain after operation had a negative correlation with LLC(P=0.018),but had no significant correlation with other parameters(P>0.05).The VAS score of patients with ?PI-LL?<10° at the last follow-up was significantly greater than that of patients with ?PI-LL??10°.The difference was statistically significant(P=0.004).The last follow-up ?PI-LL?<10 has no significant difference in ODI index between two groups.Conclusion: 1.Lumbar fusion can change the parameters of spinal pelvis and improve the quality of postoperative patients;2.There is a certain correlation between the parameters of the posterior spine and the pelvis.The postoperative LLC,LLI,?PI-LL? and ODI index are correlated with the VAS score.When assessing the spine pelvic parameters and quality of life scores,the focus should be on the correlation among LLC,LLI,?PI-LL? and quality of life scores;3.Patients with chronic low back pain after surgery had poor recovery of lumbar curvature and poor postoperative quality;4 Chronic low back pain and postoperative ?PI-LL? ?10° were in a sagittal imbalance and their quality of life was poor.Therefore,reasonable matching of PI and LL during operation can effectively control the occurrence of chronic low back pain in patients after operation.