Karim Rizwan Nathani1, Muhammad Danish Barakzai2, Hamid Hussain Rai1, Komal Naeem1, Fatima Mubarak2, Haissan Iftikhar3, Saad Akhtar Khan4, Syed Ather Enam1. 1. Section of Neurosurgery, Department of Surgery, The Aga Khan University, Karachi, Pakistan. 2. Department of Radiology, The Aga Khan University, Karachi, Pakistan. 3. Section of ENT, Department of Surgery, The Aga Khan University, Karachi, Pakistan. 4. Section of Neurosurgery, Department of Surgery, The Liaquat National Hospital, Stadium Road, Karachi, 74800, Pakistan. drsaadkhan84@gmail.com.
Abstract
OBJECTIVES: Redundant Nerve Root (RNR) is a tortuous and elongated radiological appearance of cauda equina on Magnetic Resonance Imaging (MRI) in Lumbar Spinal Canal Stenosis (LSCS) patients. This study evaluated preoperative spinal morphometry associated with the development of RNR. METHODS: The retrospective cohort was conducted at The Aga Khan University Hospital, and included patients undergoing decompressive spinal surgery secondary to degenerative LSCS in 2015. The patients were divided into two groups with respect to the presence of preoperative RNR. Spinal morphometry was defined by several radiological parameters, including areas of dural sac (DSA), spinal canal, spinal foramen, facets, and spinal joints, and bilateral angles based on vertebral anatomy. RESULTS: A total of 55 patients were enrolled with a mean age of 57.1 years, in which 22 (40%) expressed RNR in their MRI. The RNR group had significantly lower mean DSA (59.64 vs 84.01 mm2; p = 0.028), bilateral posterior facet angle (Right: 33.84 vs 46.21, p = 0.004; Left: 36.43 vs 43.80, p = 0.039) and higher bilateral anterior facet angles (Right: 54.85 vs 44.57, p = 0.026; Left: 55.27 vs 46.36, p = 0.050) compared to the non-RNR group. The other bidimensional and angular parameters did not observe any statistical difference between the two groups. CONCLUSION: RNR was associated with a higher degree of stenosis in patients with LSCS. Bilateral anterior and posterior facets angles contribute to its development, indicating particular spinal morphology to be vulnerable to the stenotic disease.
OBJECTIVES: Redundant Nerve Root (RNR) is a tortuous and elongated radiological appearance of cauda equina on Magnetic Resonance Imaging (MRI) in Lumbar Spinal Canal Stenosis (LSCS) patients. This study evaluated preoperative spinal morphometry associated with the development of RNR. METHODS: The retrospective cohort was conducted at The Aga Khan University Hospital, and included patients undergoing decompressive spinal surgery secondary to degenerative LSCS in 2015. The patients were divided into two groups with respect to the presence of preoperative RNR. Spinal morphometry was defined by several radiological parameters, including areas of dural sac (DSA), spinal canal, spinal foramen, facets, and spinal joints, and bilateral angles based on vertebral anatomy. RESULTS: A total of 55 patients were enrolled with a mean age of 57.1 years, in which 22 (40%) expressed RNR in their MRI. The RNR group had significantly lower mean DSA (59.64 vs 84.01 mm2; p = 0.028), bilateral posterior facet angle (Right: 33.84 vs 46.21, p = 0.004; Left: 36.43 vs 43.80, p = 0.039) and higher bilateral anterior facet angles (Right: 54.85 vs 44.57, p = 0.026; Left: 55.27 vs 46.36, p = 0.050) compared to the non-RNR group. The other bidimensional and angular parameters did not observe any statistical difference between the two groups. CONCLUSION: RNR was associated with a higher degree of stenosis in patients with LSCS. Bilateral anterior and posterior facets angles contribute to its development, indicating particular spinal morphology to be vulnerable to the stenotic disease.