ABSTRACT
BACKGROUND: Clinical value of the nerve root sedimentation sign in patients with lumbar spinal stenosis (LSS) is still uncertain.OBJECTIVE: To investigate the positive rate and correlation of the nerve root sedimentation sign in patients with LSS.METHODS: Totally 281 patients complaining lumbago or low back pain underwent MRI examination in the Orthopedic Clinic or Ward of Jinshan Hospital of Fudan University, including 119 males and 162 females. The cross-sectional area and sagittal diameter of the spinal canal were measured, and the patients were then divided into two groups according to the presence and absence of LSS. Finally, the positive rate of nerve root sedimentation sign was compared.RESULTS AND CONCLUSION: (1) Grouping based on the presence and absence dural sac cross-sectional area stenosis: the positive rate of nerve root sedimentation sign in sever, non, and mild LSS patients was 91.4%, 39.6%,and 53.5%, respectively, and the difference was significant (P < 0.05), but the positive rate showed no significant difference between mild and moderate as well as moderate and severe LSS patients. (2) Grouping according to the presence and absence spinal canal sagittal diameter stenosis: there was a significant difference in the positive rate of nerve root sedimentation sign between non-LSS and LSS patients (44.3% vs. 76.1%, χ2=21.469, P=0.000). (3) Grouping based on the dural sac cross-sectional area combined with spinal canal sagittal diameter: the dural sac cross-sectional area < 120 mm2 or the spinal canal sagittal diameter < 10 mm indicating LSS, there was a significant difference in the positive rate of nerve root sedimentation sign between non-LSS and LSS patients (40.6% vs.80.6%,χ2=30.539, P=0.000). (4) These results indicate that the diagnosis value of nerve root sedimentation sign in LSS is still under discussion. Although a positive sedimentation sign exclusively and reliably occurs in patients with severe LSS, it is also higher in patients without LSS. It may be inappropriate to take nerve root sedimentation sign as a diagnostic tool, but when combined with dural sac cross-sectional area and sagittal canal subsidence, it will be of great significance for the diagnosis of LSS.