The Prognostic Prediction And Risk Factors Of Nerve Root Sedimentation Sign On Surgical Treatment Of Lumbar Spinal Stenosis

Objective: To evaluate the effectiveness of nerve root sedimentation sign(SedSign)on prognostic prediction for surgical treatment of lumbar spinal stenosis(LSS)and the risk factors of SedSign.Methods: This was a retrospective study.Consecutive inpatients from May 2019 to December 2021 with symptomatic LSS who underwent surgical intervention in the orthopedic department at the First Hospital of China Medical University were included.Preoperative 3.0 Tesla MRI of the lumbar spine was performed and used to evaluated the SedSign.According to the SedSign result,we divided the participants into a positive SedSign(PS)group and a negative SedSign(NS)group.VAS-back,VAS-leg and JOA score of the participants were assessed preoperatively and 12 months postoperatively.Modified Macnab criteria were evaluated for NS and PS groups at the final follow-up.Results: The JOA,VAS-leg and VAS-back at 12-months during follow-up in the two groups were significantly improved compared with those before operation(P < 0 001).There was no significant difference in the decrease of VAS-leg(P = 0.83)and VAS-back(P = 0.37)between the two groups.The improvement of the JOA score in the NS group was superior than that in PS group(P = 0.03).In subgroup of PELD,the improvement of JOA score in NS group was superior to that in PS group(P = 0.02).There was no significant difference in the excellent and good rate of modified Macnab criteria between the two groups(NS: 77.19%,PS: 69.49%;P = 0.26).Whereas,the excellent rate of modified Macnab criteria in the NS group was superior than that in the PS group with statistical significance(PS: 30.51%,NS: 61.40%;P < 0.001).According to logistic regression analysis,positive SedSign was significantly correlated with the number of stenosis segments(OR of two stenosis segments: 2.28,P = 0.03;OR of three or more stenosis segments: 11.58,P < 0.01).Conclusion: Compared to LSS patients with negative SedSign,patients with positive SedSign had limited postoperative(especially PELD)functional improvement.The positive SedSign was significantly related to the number of stenosis segments.