Diagnostic value of the nerve root sedimentation sign for lumbar spinal stenosis / 中华骨科杂志

ABSTRACT

Objective To evaluate the diagnostic value of the nerve root sedimentation sign for lumbar spinal stenosis and improve morphological classification.Methods This is a retrospective radiologic study.From November 2012 to November 2013,511 patients who carried out MR examination due to backache together with intermittent claudication were selected.Cross-section MRI images at the narrowest layer of canalis spinalis were chosen.The patients were further divided into 7 groups,A1,A2,A3,A4,B,C,and D based on Schizas.The dural sac cross-sectional area (DSCA) of each group was measured.The groups without difference were merged.A new method to grade nerve root sedimentation was developed.Then,the correlation and consistency of nerve root sedimentation dichotomy,Schizas classification,new nerve root sedimentation classification and DSCA classification were compared.The differences of patients' Oswestry disability index (ODI) which adopted new classification method were compared.Results Results show there are no statistical significance between groups A1 and A2,groups A4 and B,or groups C and D in DSCA.After the merger,new nerve root sedimentation classification includes negative,a,b,and c.The correlation between nerve root sedimentation dichotomy and DSCA method is rs=0.579,and the consistency is κ=0.254.The correlation between new nerve root sedimentation classification method and DSCA method is rs=0.722,and the consistency is κ=0.381.The scores improve compared with the first two classification methods.ODI score difference of each group which adopted new nerve root sedimentation classification method has statistical signiftcance (F=17.972,P=0.000).Pairwise comparison shows only group c differs significantly from other groups (P＜0.05).Conclusion The new nerve root sedimentation classification method is more effective than nerve root sedimentation dichotomy and Schizas grading.It reflects the severity degree of patients'clinical symptoms to some extent.