OBJECTIVE:To investigate the effect of spinal manipulation(SM)on degenerative scoliosis by evaluating patients’visual analog scale(VAS)scores,Cobb angles,sagittal vertical axis(SVA),and apical vertebral rotation(AVR)...OBJECTIVE:To investigate the effect of spinal manipulation(SM)on degenerative scoliosis by evaluating patients’visual analog scale(VAS)scores,Cobb angles,sagittal vertical axis(SVA),and apical vertebral rotation(AVR)and to explore factors that influence treatment effect.METHODS:A total of 55 patients with degenerative scoliosis received 4 weeks of SM.After treatment,patients were divided into two groups:the remission group(VAS score<40 mm)and the non-remission group(VAS score≥40 mm).Pre-versus post-treatment VAS scores,Cobb angles,SVA,and AVR were compared in each group and in the total population.Baseline data(sex,age,symptom characteristics,duration of symptoms,VAS score,Cobb angle,SVA,and AVR)were compared between groups.Factors influencing the post-treatment VAS score were explored with multiple linear regression analysis.RESULTS:No changes were found in the Cobb angle(P=0.722)or AVR(P=0.424)after intervention in the overall population.However,the SVA(P<0.001)and VAS score(P=0.000)changed significantly after treatment.Similar changes were observed in the remission group(n=29).Multiple linear regression revealed that the only factors influencing treatment effect were symptom characteristics,SVA,and VAS score.CONCLUSION:SM relieved pain and improved sagittal imbalance in patients with degenerative scoliosis.It did not lessen the severity of coronal curvature or vertebral rotation.Factors influencing the effect of SM included symptom characteristics,VAS score,and SVA.A larger randomized trial is needed to further confirm our results.展开更多
Identifying when, where, and how India and Asia collided is a prerequisite to better understand the evolution of the Himalayan-Tibetan Plateau. Whereas with essentially the same published paleomagnetic data, a large r...Identifying when, where, and how India and Asia collided is a prerequisite to better understand the evolution of the Himalayan-Tibetan Plateau. Whereas with essentially the same published paleomagnetic data, a large range of different India-Asia collision models have been proposed in the literature. Based upon the premise of a northwards-moving Indian plate during the Cretaceous times, we analyze the significant variations in relative paleolatitude produced by a nearly 90° counterclockwise(CCW)rotation of the plate itself during the Cretaceous. Interestingly, recent studies proposed a dual-collision process with a Greater India basin or post-Neo-Tethyan ocean for the India-Asia collision, mainly in the light of divergent Cretaceous paleolatitude differences of the Tethyan Himalaya between the observed values and expected ones computed from the apparent polar wander path of the Indian plate. However, we find that these varied paleolatitude differences are mainly resulted from a nearly 90° CCW rotation of a rigid/quasi-rigid Greater Indian plate during the Cretaceous. On the other hand, when the Indian craton and Tethyan Himalaya moved as two individual blocks rather than a united rigid/quasi-rigid Greater Indian plate before the India-Asia collision, current available Cretaceous paleomagnetic data permit only multiple paleogeographic solutions for the tectonic relationship between the Indian plate and the Tethyan Himalayan terrane. We therefore argue that the tectonic relationship between the Indian plate and the Tethyan Himalayan terrane cannot be uniquely constrained by current paleomagnetic data in the absence of sufficient geological evidence, and the so-called Greater India basin model is just one of the ideal scenarios.展开更多
Purpose: The isocenter of a medical linac system is a frequently used concept in clinical practice. However, so far not all the isocenters are rigorously defined. This work is intended as an attempt of deriving consis...Purpose: The isocenter of a medical linac system is a frequently used concept in clinical practice. However, so far not all the isocenters are rigorously defined. This work is intended as an attempt of deriving consistent and operable isocenter definitions. Methods: The isocenter definition is based on a fundamental concept, the axis of rotation of a rigid body. The axis of rotation is determined using the trajectory of any point on a plane that intersects the rigid body. A point on the axis of rotation is found through the minimal bounding sphere of the trajectory when the rigid body makes a full rotation. The essential mathematical tool of the isocenter definition system is three-dimensional coordinate transformation. Results: The axes of rotation of the linac collimator, gantry, and couch are established first. The linac mechanical isocenter (linac isocenter) is defined as the center of a circle that best fits the trajectory of a select linac X-ray source position. The axis of rotation and the minimal bounding sphere are cornerstones for the rotation isocenters of the collimator, gantry and couch. The definition of radiation isocenter incorporates a surrogate of the useful beam axis. Conclusions: A framework of isocenter definitions for medical linacs is presented in this manuscript. Consistent meanings of the mechanical and radiation isocenters can be achieved using this approach.展开更多
基金Supported by the Special Subject for the Construction of the National Traditional Chinese Medicine Clinical Research Base Effect of Spinal Manipulation on Degenerative Scoliosis and Factors Influencing Treatment Effect(JDZX2015271)Basic Scientific Research Project of Chinese Academy of Traditional Chinese Medicine Clinical and Experimental Study on Delaying The Degeneration of Bone and Joint(ZZ10-022)。
文摘OBJECTIVE:To investigate the effect of spinal manipulation(SM)on degenerative scoliosis by evaluating patients’visual analog scale(VAS)scores,Cobb angles,sagittal vertical axis(SVA),and apical vertebral rotation(AVR)and to explore factors that influence treatment effect.METHODS:A total of 55 patients with degenerative scoliosis received 4 weeks of SM.After treatment,patients were divided into two groups:the remission group(VAS score<40 mm)and the non-remission group(VAS score≥40 mm).Pre-versus post-treatment VAS scores,Cobb angles,SVA,and AVR were compared in each group and in the total population.Baseline data(sex,age,symptom characteristics,duration of symptoms,VAS score,Cobb angle,SVA,and AVR)were compared between groups.Factors influencing the post-treatment VAS score were explored with multiple linear regression analysis.RESULTS:No changes were found in the Cobb angle(P=0.722)or AVR(P=0.424)after intervention in the overall population.However,the SVA(P<0.001)and VAS score(P=0.000)changed significantly after treatment.Similar changes were observed in the remission group(n=29).Multiple linear regression revealed that the only factors influencing treatment effect were symptom characteristics,SVA,and VAS score.CONCLUSION:SM relieved pain and improved sagittal imbalance in patients with degenerative scoliosis.It did not lessen the severity of coronal curvature or vertebral rotation.Factors influencing the effect of SM included symptom characteristics,VAS score,and SVA.A larger randomized trial is needed to further confirm our results.
基金financially supported by the Strategic Priority Research Program (B type) of the Chinese Academy of Sciences (Grant No. XDB03010404)
文摘Identifying when, where, and how India and Asia collided is a prerequisite to better understand the evolution of the Himalayan-Tibetan Plateau. Whereas with essentially the same published paleomagnetic data, a large range of different India-Asia collision models have been proposed in the literature. Based upon the premise of a northwards-moving Indian plate during the Cretaceous times, we analyze the significant variations in relative paleolatitude produced by a nearly 90° counterclockwise(CCW)rotation of the plate itself during the Cretaceous. Interestingly, recent studies proposed a dual-collision process with a Greater India basin or post-Neo-Tethyan ocean for the India-Asia collision, mainly in the light of divergent Cretaceous paleolatitude differences of the Tethyan Himalaya between the observed values and expected ones computed from the apparent polar wander path of the Indian plate. However, we find that these varied paleolatitude differences are mainly resulted from a nearly 90° CCW rotation of a rigid/quasi-rigid Greater Indian plate during the Cretaceous. On the other hand, when the Indian craton and Tethyan Himalaya moved as two individual blocks rather than a united rigid/quasi-rigid Greater Indian plate before the India-Asia collision, current available Cretaceous paleomagnetic data permit only multiple paleogeographic solutions for the tectonic relationship between the Indian plate and the Tethyan Himalayan terrane. We therefore argue that the tectonic relationship between the Indian plate and the Tethyan Himalayan terrane cannot be uniquely constrained by current paleomagnetic data in the absence of sufficient geological evidence, and the so-called Greater India basin model is just one of the ideal scenarios.
文摘Purpose: The isocenter of a medical linac system is a frequently used concept in clinical practice. However, so far not all the isocenters are rigorously defined. This work is intended as an attempt of deriving consistent and operable isocenter definitions. Methods: The isocenter definition is based on a fundamental concept, the axis of rotation of a rigid body. The axis of rotation is determined using the trajectory of any point on a plane that intersects the rigid body. A point on the axis of rotation is found through the minimal bounding sphere of the trajectory when the rigid body makes a full rotation. The essential mathematical tool of the isocenter definition system is three-dimensional coordinate transformation. Results: The axes of rotation of the linac collimator, gantry, and couch are established first. The linac mechanical isocenter (linac isocenter) is defined as the center of a circle that best fits the trajectory of a select linac X-ray source position. The axis of rotation and the minimal bounding sphere are cornerstones for the rotation isocenters of the collimator, gantry and couch. The definition of radiation isocenter incorporates a surrogate of the useful beam axis. Conclusions: A framework of isocenter definitions for medical linacs is presented in this manuscript. Consistent meanings of the mechanical and radiation isocenters can be achieved using this approach.