The Experts below are selected from a list of 219 Experts worldwide ranked by ideXlab platform
Richard Nelson - One of the best experts on this subject based on the ideXlab platform.
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Traumatic posterior atlantoaxial dislocation with associated C1 Jefferson Fracture and bilateral vertebral artery occlusion without Odontoid Process Fracture or neurological deficit
European Spine Journal, 2019Co-Authors: Mark Nowell, Richard NelsonAbstract:Purpose Traumatic atlantoaxial dislocation (AAD) is usually associated with fatal high-velocity road traffic accidents (Xu et al. in Medicine (Baltimore) 94:e1768, 2015 ). There are few reports of survival following posterior AAD without Odontoid Fracture (Xu et al. 2015 ; Zhen et al. in Arch Orthop Trauma Surg 131:681–685, 2011 ; de Carvalho and Swash in Handb Clin Neurol 119:435–448, 2014 ). Method We present a previously undescribed case of posterior AAD associated with a C1 Jefferson Fracture but no Odontoid Fracture and bilateral vertebral artery occlusion without neurological deficit. Conclusion The presence of bilateral vertebral artery occlusion raised challenges in the surgical management. Survival was only possible due to the presence of robust cerebral collateral circulation.
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traumatic posterior atlantoaxial dislocation with associated c1 jefferson Fracture and bilateral vertebral artery occlusion without Odontoid Process Fracture or neurological deficit
European Spine Journal, 2019Co-Authors: Mark Nowell, Richard NelsonAbstract:Purpose Traumatic atlantoaxial dislocation (AAD) is usually associated with fatal high-velocity road traffic accidents (Xu et al. in Medicine (Baltimore) 94:e1768, 2015). There are few reports of survival following posterior AAD without Odontoid Fracture (Xu et al. 2015; Zhen et al. in Arch Orthop Trauma Surg 131:681–685, 2011; de Carvalho and Swash in Handb Clin Neurol 119:435–448, 2014).
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Traumatic posterior atlantoaxial dislocation with associated C1 Jefferson Fracture and bilateral vertebral artery occlusion without Odontoid Process Fracture or neurological deficit.
European spine journal : official publication of the European Spine Society the European Spinal Deformity Society and the European Section of the Cerv, 2018Co-Authors: Mark Nowell, Richard NelsonAbstract:Traumatic atlantoaxial dislocation (AAD) is usually associated with fatal high-velocity road traffic accidents (Xu et al. in Medicine (Baltimore) 94:e1768, 2015). There are few reports of survival following posterior AAD without Odontoid Fracture (Xu et al. 2015; Zhen et al. in Arch Orthop Trauma Surg 131:681-685, 2011; de Carvalho and Swash in Handb Clin Neurol 119:435-448, 2014). We present a previously undescribed case of posterior AAD associated with a C1 Jefferson Fracture but no Odontoid Fracture and bilateral vertebral artery occlusion without neurological deficit. The presence of bilateral vertebral artery occlusion raised challenges in the surgical management. Survival was only possible due to the presence of robust cerebral collateral circulation.
Yang Zhang - One of the best experts on this subject based on the ideXlab platform.
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an in vitro biomechanical evaluation of an expansive double threaded bi directional compression screw for fixation of type ii Odontoid Process Fractures a squire compliant article
Medicine, 2017Co-Authors: Ning Liu, Li Tian, Rongxian Jiang, Lei Shi, Wei Lei, Yang ZhangAbstract:Odontoid Process Fracture accounts for 5% to 15% of all cervical spine injuries, and the rate is higher among elderly people. The anterior cannulated screw fixation has been widely used in Odontoid Process Fracture, but the fixation strength may still be limited under some circumstances. This study aims to investigate the biomechanical fixation strength of expansive double-threaded bi-directional compression screw (EDBCS) compared with cannulated lag screw (CLS) and improved Herbert screw (IHS) for fixation of type II Odontoid Process Fracture. Thirty fresh cadaveric C2 vertebrae specimens were harvested and randomly divided into groups A, B, and C. A type II Fracture model was simulated by osteotomy. Then the specimens of the 3 groups were stabilized with a single CLS, IHS, or EDBCS, respectively. Each specimen was tested in torsion from 0° to 1.25° for 75 s in each of 5 cycles clockwise and 5 cycles anticlockwise. Shear and tensile forces were applied at the anterior-to-posterior and proximal-to-distal directions, respectively, both to a maximum load of 45 N and at a speed of 1 mm/min. The mean torsional stiffness was 0.309 N m/deg for IHS and 0.389 N m/deg for EDBCS, which were significantly greater compared with CLS, respectively (0.169 N m/deg) (P < .05 and P < .05). The mean shear stiffness for the EDBCS was 238 N/mm, which was significantly greater than CLS (150 N/mm) and IHS (132 N/mm) (P < .05 and P < .05). All 3 screws only partly restored tensile stiffness, but not significantly. Fixation with the EDBCS can improve the biomechanical strength for Odontoid Process Fracture compared with CLS and IHS, especially in terms of torsional and shear stiffness.
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An in vitro biomechanical evaluation of an expansive double-threaded bi-directional compression screw for fixation of type II Odontoid Process Fractures: A SQUIRE-compliant article.
Medicine, 2017Co-Authors: Ning Liu, Lei Shi, Wei Lei, Jiang Rongxian, Yang ZhangAbstract:Odontoid Process Fracture accounts for 5% to 15% of all cervical spine injuries, and the rate is higher among elderly people. The anterior cannulated screw fixation has been widely used in Odontoid Process Fracture, but the fixation strength may still be limited under some circumstances. This study aims to investigate the biomechanical fixation strength of expansive double-threaded bi-directional compression screw (EDBCS) compared with cannulated lag screw (CLS) and improved Herbert screw (IHS) for fixation of type II Odontoid Process Fracture. Thirty fresh cadaveric C2 vertebrae specimens were harvested and randomly divided into groups A, B, and C. A type II Fracture model was simulated by osteotomy. Then the specimens of the 3 groups were stabilized with a single CLS, IHS, or EDBCS, respectively. Each specimen was tested in torsion from 0° to 1.25° for 75 s in each of 5 cycles clockwise and 5 cycles anticlockwise. Shear and tensile forces were applied at the anterior-to-posterior and proximal-to-distal directions, respectively, both to a maximum load of 45 N and at a speed of 1 mm/min. The mean torsional stiffness was 0.309 N m/deg for IHS and 0.389 N m/deg for EDBCS, which were significantly greater compared with CLS, respectively (0.169 N m/deg) (P
Mark Nowell - One of the best experts on this subject based on the ideXlab platform.
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Traumatic posterior atlantoaxial dislocation with associated C1 Jefferson Fracture and bilateral vertebral artery occlusion without Odontoid Process Fracture or neurological deficit
European Spine Journal, 2019Co-Authors: Mark Nowell, Richard NelsonAbstract:Purpose Traumatic atlantoaxial dislocation (AAD) is usually associated with fatal high-velocity road traffic accidents (Xu et al. in Medicine (Baltimore) 94:e1768, 2015 ). There are few reports of survival following posterior AAD without Odontoid Fracture (Xu et al. 2015 ; Zhen et al. in Arch Orthop Trauma Surg 131:681–685, 2011 ; de Carvalho and Swash in Handb Clin Neurol 119:435–448, 2014 ). Method We present a previously undescribed case of posterior AAD associated with a C1 Jefferson Fracture but no Odontoid Fracture and bilateral vertebral artery occlusion without neurological deficit. Conclusion The presence of bilateral vertebral artery occlusion raised challenges in the surgical management. Survival was only possible due to the presence of robust cerebral collateral circulation.
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traumatic posterior atlantoaxial dislocation with associated c1 jefferson Fracture and bilateral vertebral artery occlusion without Odontoid Process Fracture or neurological deficit
European Spine Journal, 2019Co-Authors: Mark Nowell, Richard NelsonAbstract:Purpose Traumatic atlantoaxial dislocation (AAD) is usually associated with fatal high-velocity road traffic accidents (Xu et al. in Medicine (Baltimore) 94:e1768, 2015). There are few reports of survival following posterior AAD without Odontoid Fracture (Xu et al. 2015; Zhen et al. in Arch Orthop Trauma Surg 131:681–685, 2011; de Carvalho and Swash in Handb Clin Neurol 119:435–448, 2014).
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Traumatic posterior atlantoaxial dislocation with associated C1 Jefferson Fracture and bilateral vertebral artery occlusion without Odontoid Process Fracture or neurological deficit.
European spine journal : official publication of the European Spine Society the European Spinal Deformity Society and the European Section of the Cerv, 2018Co-Authors: Mark Nowell, Richard NelsonAbstract:Traumatic atlantoaxial dislocation (AAD) is usually associated with fatal high-velocity road traffic accidents (Xu et al. in Medicine (Baltimore) 94:e1768, 2015). There are few reports of survival following posterior AAD without Odontoid Fracture (Xu et al. 2015; Zhen et al. in Arch Orthop Trauma Surg 131:681-685, 2011; de Carvalho and Swash in Handb Clin Neurol 119:435-448, 2014). We present a previously undescribed case of posterior AAD associated with a C1 Jefferson Fracture but no Odontoid Fracture and bilateral vertebral artery occlusion without neurological deficit. The presence of bilateral vertebral artery occlusion raised challenges in the surgical management. Survival was only possible due to the presence of robust cerebral collateral circulation.
Ning Liu - One of the best experts on this subject based on the ideXlab platform.
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an in vitro biomechanical evaluation of an expansive double threaded bi directional compression screw for fixation of type ii Odontoid Process Fractures a squire compliant article
Medicine, 2017Co-Authors: Ning Liu, Li Tian, Rongxian Jiang, Lei Shi, Wei Lei, Yang ZhangAbstract:Odontoid Process Fracture accounts for 5% to 15% of all cervical spine injuries, and the rate is higher among elderly people. The anterior cannulated screw fixation has been widely used in Odontoid Process Fracture, but the fixation strength may still be limited under some circumstances. This study aims to investigate the biomechanical fixation strength of expansive double-threaded bi-directional compression screw (EDBCS) compared with cannulated lag screw (CLS) and improved Herbert screw (IHS) for fixation of type II Odontoid Process Fracture. Thirty fresh cadaveric C2 vertebrae specimens were harvested and randomly divided into groups A, B, and C. A type II Fracture model was simulated by osteotomy. Then the specimens of the 3 groups were stabilized with a single CLS, IHS, or EDBCS, respectively. Each specimen was tested in torsion from 0° to 1.25° for 75 s in each of 5 cycles clockwise and 5 cycles anticlockwise. Shear and tensile forces were applied at the anterior-to-posterior and proximal-to-distal directions, respectively, both to a maximum load of 45 N and at a speed of 1 mm/min. The mean torsional stiffness was 0.309 N m/deg for IHS and 0.389 N m/deg for EDBCS, which were significantly greater compared with CLS, respectively (0.169 N m/deg) (P < .05 and P < .05). The mean shear stiffness for the EDBCS was 238 N/mm, which was significantly greater than CLS (150 N/mm) and IHS (132 N/mm) (P < .05 and P < .05). All 3 screws only partly restored tensile stiffness, but not significantly. Fixation with the EDBCS can improve the biomechanical strength for Odontoid Process Fracture compared with CLS and IHS, especially in terms of torsional and shear stiffness.
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An in vitro biomechanical evaluation of an expansive double-threaded bi-directional compression screw for fixation of type II Odontoid Process Fractures: A SQUIRE-compliant article.
Medicine, 2017Co-Authors: Ning Liu, Lei Shi, Wei Lei, Jiang Rongxian, Yang ZhangAbstract:Odontoid Process Fracture accounts for 5% to 15% of all cervical spine injuries, and the rate is higher among elderly people. The anterior cannulated screw fixation has been widely used in Odontoid Process Fracture, but the fixation strength may still be limited under some circumstances. This study aims to investigate the biomechanical fixation strength of expansive double-threaded bi-directional compression screw (EDBCS) compared with cannulated lag screw (CLS) and improved Herbert screw (IHS) for fixation of type II Odontoid Process Fracture. Thirty fresh cadaveric C2 vertebrae specimens were harvested and randomly divided into groups A, B, and C. A type II Fracture model was simulated by osteotomy. Then the specimens of the 3 groups were stabilized with a single CLS, IHS, or EDBCS, respectively. Each specimen was tested in torsion from 0° to 1.25° for 75 s in each of 5 cycles clockwise and 5 cycles anticlockwise. Shear and tensile forces were applied at the anterior-to-posterior and proximal-to-distal directions, respectively, both to a maximum load of 45 N and at a speed of 1 mm/min. The mean torsional stiffness was 0.309 N m/deg for IHS and 0.389 N m/deg for EDBCS, which were significantly greater compared with CLS, respectively (0.169 N m/deg) (P
Lei Shi - One of the best experts on this subject based on the ideXlab platform.
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an in vitro biomechanical evaluation of an expansive double threaded bi directional compression screw for fixation of type ii Odontoid Process Fractures a squire compliant article
Medicine, 2017Co-Authors: Ning Liu, Li Tian, Rongxian Jiang, Lei Shi, Wei Lei, Yang ZhangAbstract:Odontoid Process Fracture accounts for 5% to 15% of all cervical spine injuries, and the rate is higher among elderly people. The anterior cannulated screw fixation has been widely used in Odontoid Process Fracture, but the fixation strength may still be limited under some circumstances. This study aims to investigate the biomechanical fixation strength of expansive double-threaded bi-directional compression screw (EDBCS) compared with cannulated lag screw (CLS) and improved Herbert screw (IHS) for fixation of type II Odontoid Process Fracture. Thirty fresh cadaveric C2 vertebrae specimens were harvested and randomly divided into groups A, B, and C. A type II Fracture model was simulated by osteotomy. Then the specimens of the 3 groups were stabilized with a single CLS, IHS, or EDBCS, respectively. Each specimen was tested in torsion from 0° to 1.25° for 75 s in each of 5 cycles clockwise and 5 cycles anticlockwise. Shear and tensile forces were applied at the anterior-to-posterior and proximal-to-distal directions, respectively, both to a maximum load of 45 N and at a speed of 1 mm/min. The mean torsional stiffness was 0.309 N m/deg for IHS and 0.389 N m/deg for EDBCS, which were significantly greater compared with CLS, respectively (0.169 N m/deg) (P < .05 and P < .05). The mean shear stiffness for the EDBCS was 238 N/mm, which was significantly greater than CLS (150 N/mm) and IHS (132 N/mm) (P < .05 and P < .05). All 3 screws only partly restored tensile stiffness, but not significantly. Fixation with the EDBCS can improve the biomechanical strength for Odontoid Process Fracture compared with CLS and IHS, especially in terms of torsional and shear stiffness.
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An in vitro biomechanical evaluation of an expansive double-threaded bi-directional compression screw for fixation of type II Odontoid Process Fractures: A SQUIRE-compliant article.
Medicine, 2017Co-Authors: Ning Liu, Lei Shi, Wei Lei, Jiang Rongxian, Yang ZhangAbstract:Odontoid Process Fracture accounts for 5% to 15% of all cervical spine injuries, and the rate is higher among elderly people. The anterior cannulated screw fixation has been widely used in Odontoid Process Fracture, but the fixation strength may still be limited under some circumstances. This study aims to investigate the biomechanical fixation strength of expansive double-threaded bi-directional compression screw (EDBCS) compared with cannulated lag screw (CLS) and improved Herbert screw (IHS) for fixation of type II Odontoid Process Fracture. Thirty fresh cadaveric C2 vertebrae specimens were harvested and randomly divided into groups A, B, and C. A type II Fracture model was simulated by osteotomy. Then the specimens of the 3 groups were stabilized with a single CLS, IHS, or EDBCS, respectively. Each specimen was tested in torsion from 0° to 1.25° for 75 s in each of 5 cycles clockwise and 5 cycles anticlockwise. Shear and tensile forces were applied at the anterior-to-posterior and proximal-to-distal directions, respectively, both to a maximum load of 45 N and at a speed of 1 mm/min. The mean torsional stiffness was 0.309 N m/deg for IHS and 0.389 N m/deg for EDBCS, which were significantly greater compared with CLS, respectively (0.169 N m/deg) (P
