Masoud Poureisa1, Mohammad Hossein Daghighi1, Payam Eftekhari1, Kaveh Rezaei Bookani2, Daniel Fadaei Fouladi3. 1. Department of Radiology, Imam Reza Hospital, Tabriz University of Medical Sciences, Tabriz, Iran. 2. Department of Radiology, Imam Khomeini Hospital, Urmia University of Medical Sciences, Urmia, Iran. 3. Neurosciences Research Center, Imam Reza Teaching Hospital, Tabriz University of Medical Sciences, PO Box: 5166614756, Golgasht Street, Tabriz, Iran. medicorelax@yahoo.com.
Abstract
PURPOSE: The purpose of this study was to evaluate magnetic resonance (MR)-detected redundant nerve roots (RNRs) of the cauda equina in patients with lumbar spinal canal stenosis. METHODS: A total of 500 lumbar MR studies in patients with lumbar spinal canal stenosis were reviewed for the presence and characteristics of RNRs of the cauda equina. The length of the RNRs relative to the height of the upper vertebral body of the level of the stenosis was used as a prognostic indicator. RESULTS: RNRs were detected in 15% of the patients, the majority above the level of the stenosis (85%) and loop shaped (72%). Advanced age (i.e., ≥56 years old, odds ratio=1), a lumbar spinal canal stenosis at L2-4 (odds ratio=2.5), and the presence of an intracanal protuberance with sharp margin in the site of the stenosis (odds ratio=7.2) were independent risk factors for the development of RNRs. A direct, significant correlation was found between the relative length of the RNRs and patients' age (Pearson r=0.36, p=0.001). The mean relative length of the RNRs was significantly higher in patients with RNRs located above the level of the stenosis than those with RNRs located below the site of the block. The degree of stenosis was associated with neither the presence nor the relative length of the RNRs. CONCLUSIONS: With an occurrence rate of 15%, RNRs of the cauda equina are not uncommon in cases with lumbar spinal canal stenosis. Advanced age, a canal stenosis at L2-4, and the presence of a sharp intracanal protuberance in the site of the stenosis are the related risk factors. Patients' age and the location of RNRs may be of prognostic value.
PURPOSE: The purpose of this study was to evaluate magnetic resonance (MR)-detected redundant nerve roots (RNRs) of the cauda equina in patients with lumbar spinal canal stenosis. METHODS: A total of 500 lumbar MR studies in patients with lumbar spinal canal stenosis were reviewed for the presence and characteristics of RNRs of the cauda equina. The length of the RNRs relative to the height of the upper vertebral body of the level of the stenosis was used as a prognostic indicator. RESULTS: RNRs were detected in 15% of the patients, the majority above the level of the stenosis (85%) and loop shaped (72%). Advanced age (i.e., ≥56 years old, odds ratio=1), a lumbar spinal canal stenosis at L2-4 (odds ratio=2.5), and the presence of an intracanal protuberance with sharp margin in the site of the stenosis (odds ratio=7.2) were independent risk factors for the development of RNRs. A direct, significant correlation was found between the relative length of the RNRs and patients' age (Pearson r=0.36, p=0.001). The mean relative length of the RNRs was significantly higher in patients with RNRs located above the level of the stenosis than those with RNRs located below the site of the block. The degree of stenosis was associated with neither the presence nor the relative length of the RNRs. CONCLUSIONS: With an occurrence rate of 15%, RNRs of the cauda equina are not uncommon in cases with lumbar spinal canal stenosis. Advanced age, a canal stenosis at L2-4, and the presence of a sharp intracanal protuberance in the site of the stenosis are the related risk factors. Patients' age and the location of RNRs may be of prognostic value.
Entities:
Keywords:
Degree of stenosis; Demographics; Location, length; Lumbar spinal canal stenosis; Magnetic resonance imaging; Prognosis; Redundant nerve roots (RNRs) of the cauda equina; Risk factor
Authors: Sebastian Winklhofer; Ulrike Held; Jakob M Burgstaller; Tim Finkenstaedt; Nicolae Bolog; Nils Ulrich; Johann Steurer; Gustav Andreisek; Filippo Del Grande Journal: Eur Spine J Date: 2016-06-22 Impact factor: 3.134