Nerve Root Sedimentation Sign: A Potential Diagnosis of Symptomatic Lumbar Spinal Stenosis

Introduction: Nerve root sedimentation sign is natural sedimentation of lumbar nerve roots to the dorsal part of the dural sac seen on transverse MRI scans. This phenomenon can be taken advantage of to distinguish symptomatic lumbar spinal stenosis from nonspecific low back pain. We aimed to evaluate the clinical validity of the nerve root sedimentation sign to diagnose patients with symptomatic lumbar spinal stenosis who need surgical intervention.Methods: In this study, ۱۰۰ patients were surveyed referring to an Orthopedic Clinic with a chief complaint of chronic low back pain (LBP) for three months or more. Demographic information, physical examination, and lumbar MRI scans were obtained, then the patients were assigned to two groups of ۵۰ patients in each   namely Lumbar spinal stenosis (LSS) and LBP groups. The frequency of a positive sedimentation sign was compared between the two groups.Results: The mean age of patients was ۵۷.۹۵±۹.۸۱ years, ۶۱ of them were male, and the rest of the ۳۹ subjects were female. Nerve root sedimentation sign was positive in ۴۸ pts of the LSS group (۹۶% Sensitivity) but none in the LBP group (۱۰۰% specificity).Conclusion: A positive sedimentation sign exclusively and reliably occurs in patients with lumbar spinal stenosis, suggesting its usefulness in clinical practice. Future   studies are needed to address its sensitivity and specificity.

Keywords:

Sedimentation sign , Lumbar spinal stenosis , Low back pain