BACKGROUND:Cervical disc herniation can cause pain in the neck and shoulder area,as well as radiating pain in the upper limbs.The incidence rate is increasing year by year and tends to affect younger individuals.Fully understanding the biomechanical characteristics of the cervical spine in adolescents is of great significance for preventing and delaying the onset of cervical disc herniation in this age group. OBJECTIVE:To reconstruct cervical spine models for both healthy adolescents and adolescent patients with cervical disc herniation utilizing finite element analysis techniques,to analyze the motion range of the C1-T1 cervical vertebrae as well as the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and the cartilage of the small joints. METHODS:A normal adolescent's cervical spine and an adolescent patient with cervical disc herniation were selected in this study.The continuous scan cervical spine CT raw image data were imported into Mimics 21.0 in DICOM format.The C1-T1 vertebrae were reconstructed separately.Subsequently,the established models were imported into the 3-Matic software for disc reconstruction.The perfected models were then imported into Hypermesh software for meshing of the vertebrae,nucleus pulposus,annulus fibrosus,and ligaments,creating valid geometric models.After assigning material properties,the final models were imported into ABAQUS software to observe the joint motion range of the C1-C7 cervical vertebrae segments under different conditions,and to analyze the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and small joint cartilage of each cervical spine segment. RESULTS AND CONCLUSION:(1)In six different conditions,the joint motion range of the C1 vertebra in the cervical spine models of both normal adolescent and adolescent patient with cervical disc herniation was higher than that of the other vertebrae.Additionally,the joint motion range of each cervical spine segment in normal adolescent was greater than that in adolescent patient with cervical disc herniation.(2)In the cervical spine model of normal adolescent,the maximum stress values in the annulus fibrosus and nucleus pulposus were found on the left side during C2-3 flexion conditions(0.43 MPa and 0.17 MPa,respectively).In the cervical spine model of adolescent patient with cervical disc herniation,the maximum stress values were found on the left side during C7-T1 flexion conditions(0.54 MPa and 0.18 MPa,respectively).(3)In the cervical spine model of normal adolescent,the maximum stress value on the endplate was found on the left side of the upper endplate of C3 during flexion conditions(1.46 MPa).In the model of adolescent patient with cervical disc herniation,the maximum stress value on the endplate was found on the left side of the lower endplate of C7 during flexion conditions(1.32 MPa).(4)In the cervical spine model of normal adolescent,the maximum stress value in the small joint cartilage was found in the C2-3 left rotation conditions(0.98 MPa).In adolescent patient with cervical disc herniation,the stress in the small joint cartilage significantly increased under different conditions,especially in C1-2,with the maximum stress found during left flexion(3.50 MPa).(5)It is concluded that compared to normal adolescent,adolescent patient with cervical disc herniation exhibits altered cervical curvature and a decrease in overall joint motion range in the cervical spine.In adolescent with cervical disc herniation,there is a significant increase in stress on the annulus fibrosus,nucleus pulposus,and endplates in the C7-T1 segment.The stress on the left articular cartilage of the C1-2 is notable.Abnormal cervical curvature may be the primary factor causing these stress changes.

BACKGROUND:Ankylosing spondylitis is a chronic inflammatory disease with chronic rheumatic immunity.Soft tissue ossification and fusion and spinal stiffness can cause biomechanical changes. OBJECTIVE:To reconstruct the lumbar-sacral intervertebral disc in ankylosing spondylitis patients with lumbar kyphosis by finite element analysis,and to study the range of motion of each segment of T11-S1 and the biomechanical characteristics of annulus fibrosus and nucleus pulposus. METHODS:The imaging data were obtained from an ankylosing spondylitis patient with lumbar kyphosis.The original CT image data of continuously scanned spine were imported into Mimics 21.0 in DICOM format,and T11-S1 was reconstructed respectively.The established model was imported into 3-Matic software in the format of"Stl"to reconstruct the intervertebral disc,and the fibrous intervertebral disc model was obtained.The improved model was further imported into Hypermesh software,and the vertebra,nucleus pulposus,annulus fibrosus and ligament were mesh-divided.After the material properties were given,the model was imported into ABAQUS software to observe the range of motion of each vertebral body in seven different working conditions of T11-S1,and analyze the biomechanical characteristics of each segment of annulus fibrosus and nucleus pulposus. RESULTS AND CONCLUSION:(1)The range of motion of L1 vertebrae was higher than that of other vertebrae under six different working conditions:extension,forward flexion,rotation(left and right),and lateral flexion(left and right).The maximum range of motion was 2.18° during L1 vertebral flexion,and the minimum range of motion was 0.12° during L5 vertebral extension.(2)The annular fiber flexion at L2-L3 segments was greater than the extension(P<0.05),and the annular fiber flexion at L3-L4 and L4-L5 segments was less than the extension(P<0.05).The left rotation of L1-L2 annular fibers was greater than the right rotation(P<0.05).The left flexion of the annulus was greater than the right flexion in L1-L2,L2-L3,L3-L4,L4-L5 and L5-S1 segments(P<0.05).(3)The nucleus pulposus stresses of T11-L12,L1-L2,L2-L3,L3-L4 and L4-L5 segments in forward flexion were greater than in extension(P<0.05).The left rotation of T12-L1 and L3-L4 segments was smaller than the right rotation(P<0.05),and that of T11-T12,L1-L2,and L2-L3 segments was larger than the right rotation(P<0.05).The left flexion was larger than the right flexion in the T11-S1 segment.(4)It is concluded that in ankylosing spondylitis patients with lumbar kyphosis,the minimum range of motion of the vertebral body is located at the L5 vertebral body in extension.To prevent fractures,it is recommended to avoid exercise in the extension position.During the onset of lumbar kyphosis in patients with ankylosing spondylitis,the maximum stress of the annulus fibrosus and nucleus pulposus is located in the L1-L2 segment,which is fixed and will not alter with the change of body position.The late surgical treatment and correction of deformity should focus on releasing the pressure of the annulus fibrosus and nucleus pulposus in this segment to avoid the rupture of the annulus fibrosus and the injury of the nucleus pulposus.

BACKGROUND:Ankylosing spondylitis is a progressive inflammation of spinal stiffness deformity caused by tissue ossification and fibrosis.The posture of ankylosing spondylitis patients is abnormal and their activities are limited that minor injuries can lead to thoracolumbar fractures.Traditional medical image observation limits doctors'preoperative decision planning and postoperative disease prevention for ankylosing spondylitis treatment. OBJECTIVE:Based on the spinal model of ankylosing spondylitis patients before and after posterior spinal cancellous ossification osteotomy("Y"osteotomy for short),to explore the biomechanical changes of"Y"osteotomy and fixation in the treatment of ankylosing spondylitis. METHODS:Based on the preoperative and postoperative CT images of an ankylosing spondylitis patient who went to the Second Affiliated Hospital of Inner Mongolia Medical University,a three-dimensional spine model(T11-S1)before and after"Y"osteotomy(L3 osteotomy)was reconstructed in Mimics 19.0 software.A 7.5 Nm torque was applied to the top of T11 vertebral body to simulate the movement of the spine under six conditions:flexion,extension,left bending,right bending,left rotation and right rotation.Finally,the range of motion of each vertebral body,the stress of each intervertebral disc,and the stress of the screw rod system were simulated. RESULTS AND CONCLUSION:(1)After"Y"type osteotomy and posterior fixation,the range of motion of all vertebrae in the spine decreased,and the loss rate of upper vertebrae was large(L1:77.95%).(2)The maximum stress of the spinal intervertebral disc before operation occurred at the L1-L2 segment(0.55 MPa),and the maximum stress of the spinal intervertebral disc after operation occurred at the T11-T12 segment(0.50 MPa),and the stress of intervertebral disc below T12 was far less than that before operation.(3)The maximum stress of the screw rod system(166.67 MPa)occurred in the upper and middle segments of the rod body and the root of the pedicle screw.(4)In conclusion,the"Y"type posterior fixation operation enhances the stability of the spine and reduces the range of motion of the spine.The vertebral body decompression of the fixed segment is great and the stress-shielding phenomenon of the lower vertebral body is significant.The stiffness of the rod body and the stress concentration area of the pedicle screw should be strengthened to avoid the fracture of the rod caused by stress fatigue.

BACKGROUND:The study of the physical properties of scaffolds has always been a hot topic in the field of tissue engineering research.However,for vascular stimulating scaffolds,in addition to meeting the basic performance of the scaffold,other methods are also needed to promote the regeneration of blood vessels within the scaffold,in order to achieve the ultimate goal of repairing bone tissue. OBJECTIVE:A visualization analysis was carried out on the literature published in and outside China on scaffold stimulation for bone tissue engineering,to explore the research hotspots and research status in this field,and to provide a reference for subsequent studies. METHODS:Using the CNKI database and Web of Science core database as retrieval databases,the relevant literature on vascular scaffolds for bone tissue engineering was retrieved.The literature that did not conform to the research object was removed.The obtained data were imported into CiteSpace 6.1.R2 software.Visualization analysis was performed on authors,national institutions,and keywords in the research field. RESULTS AND CONCLUSION:(1)China,the United States,and Germany were the top three countries with the most articles on scaffold stimulation for bone tissue engineering.(2)The top 3 institutions in the CNKI database were Southern Medical University,Huazhong University of Science and Technology,and Donghua University.In the core database of Web of Science,Shanghai Jiao Tong University,Sichuan University and Chinese Academy of Sciences ranked the top 3 in terms of the number of institutional publications.(3)The top 3 keywords in the CNKI database were"tissue engineering,vascularization,angiogenesis".The top 3 keywords in the Web of Science core database were"mesenchymal stem cell,scaffold,vascularization".(4)Through the analysis of co-citation and highly cited references,the main concerns were as follows:vascularization strategies:scaffold design,angiogenic factor delivery,in vitro co-culture,and in vivo pre-vascularization.Technology:3D printing,electrospinning,vascular transplantation,vascular fusion.Mechanisms:immune regulation and macrophages,drug/growth factor delivery,the relationship between endothelial cells and osteoblasts,the paracrine relationship between bone cells and endothelial cells,signaling molecular pathways,angiogenesis,and anti-angiogenesis molecules.(5)The researches concerning vascular stimulating scaffolds in bone tissue engineering in and outside China attach great importance to the application of stem cells and 3D printing technology.Current research focuses on biological 3D printing technology,scaffold modification methods,and the development and application of intelligent biomaterials based on bone repair mechanisms.

Objective To build a comprehensive evaluation system for the operating benefit of clinical departments in cancer hospitals,so as to provide data support for the fine operation management of hospitals.Methods Literature review and semi-structured interview were used to form the index pool.Two rounds of Delphi expert consultation were used to determine the index of the evaluation system,and the analytic hierarchy process was used to determine the index weight.Finally,the weighted TOPSIS was used for empirical case analysis.Results The positive coefficient in the two rounds of Delphi expert consultation were 82.6％and 100％,the authority coefficient was 0.808,and the coordination coefficient was between 0 and 1.All indexes at all levels passed the consistency test.Finally,a comprehensive evaluation system consisting of 4 dimensions,19 indexes in surgery,16 indicators in radiotherapy and 16 indicators in internal medicine was constructed.Indicators at all levels were tested for consistency,resulting in the construction of a comprehensive evaluation system consisting of 4 dimensions,19 indicators for surgery and 16 indicators each for radiotherapy and internal medicine departments.Conclusion The comprehensive evaluation system of operating benefit of clinical departments in cancer hospitals can help hospitals and departments to find out the shortcomings of operation,build the path of operating benefit improvement,and realize the connotation improvement and high-quality development of hospitals.

Objective To build a comprehensive evaluation system for the operating benefit of clinical departments in cancer hospitals,so as to provide data support for the fine operation management of hospitals.Methods Literature review and semi-structured interview were used to form the index pool.Two rounds of Delphi expert consultation were used to determine the index of the evaluation system,and the analytic hierarchy process was used to determine the index weight.Finally,the weighted TOPSIS was used for empirical case analysis.Results The positive coefficient in the two rounds of Delphi expert consultation were 82.6％and 100％,the authority coefficient was 0.808,and the coordination coefficient was between 0 and 1.All indexes at all levels passed the consistency test.Finally,a comprehensive evaluation system consisting of 4 dimensions,19 indexes in surgery,16 indicators in radiotherapy and 16 indicators in internal medicine was constructed.Indicators at all levels were tested for consistency,resulting in the construction of a comprehensive evaluation system consisting of 4 dimensions,19 indicators for surgery and 16 indicators each for radiotherapy and internal medicine departments.Conclusion The comprehensive evaluation system of operating benefit of clinical departments in cancer hospitals can help hospitals and departments to find out the shortcomings of operation,build the path of operating benefit improvement,and realize the connotation improvement and high-quality development of hospitals.

Objective To build a comprehensive evaluation system for the operating benefit of clinical departments in cancer hospitals,so as to provide data support for the fine operation management of hospitals.Methods Literature review and semi-structured interview were used to form the index pool.Two rounds of Delphi expert consultation were used to determine the index of the evaluation system,and the analytic hierarchy process was used to determine the index weight.Finally,the weighted TOPSIS was used for empirical case analysis.Results The positive coefficient in the two rounds of Delphi expert consultation were 82.6％and 100％,the authority coefficient was 0.808,and the coordination coefficient was between 0 and 1.All indexes at all levels passed the consistency test.Finally,a comprehensive evaluation system consisting of 4 dimensions,19 indexes in surgery,16 indicators in radiotherapy and 16 indicators in internal medicine was constructed.Indicators at all levels were tested for consistency,resulting in the construction of a comprehensive evaluation system consisting of 4 dimensions,19 indicators for surgery and 16 indicators each for radiotherapy and internal medicine departments.Conclusion The comprehensive evaluation system of operating benefit of clinical departments in cancer hospitals can help hospitals and departments to find out the shortcomings of operation,build the path of operating benefit improvement,and realize the connotation improvement and high-quality development of hospitals.

Objective To build a comprehensive evaluation system for the operating benefit of clinical departments in cancer hospitals,so as to provide data support for the fine operation management of hospitals.Methods Literature review and semi-structured interview were used to form the index pool.Two rounds of Delphi expert consultation were used to determine the index of the evaluation system,and the analytic hierarchy process was used to determine the index weight.Finally,the weighted TOPSIS was used for empirical case analysis.Results The positive coefficient in the two rounds of Delphi expert consultation were 82.6％and 100％,the authority coefficient was 0.808,and the coordination coefficient was between 0 and 1.All indexes at all levels passed the consistency test.Finally,a comprehensive evaluation system consisting of 4 dimensions,19 indexes in surgery,16 indicators in radiotherapy and 16 indicators in internal medicine was constructed.Indicators at all levels were tested for consistency,resulting in the construction of a comprehensive evaluation system consisting of 4 dimensions,19 indicators for surgery and 16 indicators each for radiotherapy and internal medicine departments.Conclusion The comprehensive evaluation system of operating benefit of clinical departments in cancer hospitals can help hospitals and departments to find out the shortcomings of operation,build the path of operating benefit improvement,and realize the connotation improvement and high-quality development of hospitals.

Objective To build a comprehensive evaluation system for the operating benefit of clinical departments in cancer hospitals,so as to provide data support for the fine operation management of hospitals.Methods Literature review and semi-structured interview were used to form the index pool.Two rounds of Delphi expert consultation were used to determine the index of the evaluation system,and the analytic hierarchy process was used to determine the index weight.Finally,the weighted TOPSIS was used for empirical case analysis.Results The positive coefficient in the two rounds of Delphi expert consultation were 82.6％and 100％,the authority coefficient was 0.808,and the coordination coefficient was between 0 and 1.All indexes at all levels passed the consistency test.Finally,a comprehensive evaluation system consisting of 4 dimensions,19 indexes in surgery,16 indicators in radiotherapy and 16 indicators in internal medicine was constructed.Indicators at all levels were tested for consistency,resulting in the construction of a comprehensive evaluation system consisting of 4 dimensions,19 indicators for surgery and 16 indicators each for radiotherapy and internal medicine departments.Conclusion The comprehensive evaluation system of operating benefit of clinical departments in cancer hospitals can help hospitals and departments to find out the shortcomings of operation,build the path of operating benefit improvement,and realize the connotation improvement and high-quality development of hospitals.

Objective To build a comprehensive evaluation system for the operating benefit of clinical departments in cancer hospitals,so as to provide data support for the fine operation management of hospitals.Methods Literature review and semi-structured interview were used to form the index pool.Two rounds of Delphi expert consultation were used to determine the index of the evaluation system,and the analytic hierarchy process was used to determine the index weight.Finally,the weighted TOPSIS was used for empirical case analysis.Results The positive coefficient in the two rounds of Delphi expert consultation were 82.6％and 100％,the authority coefficient was 0.808,and the coordination coefficient was between 0 and 1.All indexes at all levels passed the consistency test.Finally,a comprehensive evaluation system consisting of 4 dimensions,19 indexes in surgery,16 indicators in radiotherapy and 16 indicators in internal medicine was constructed.Indicators at all levels were tested for consistency,resulting in the construction of a comprehensive evaluation system consisting of 4 dimensions,19 indicators for surgery and 16 indicators each for radiotherapy and internal medicine departments.Conclusion The comprehensive evaluation system of operating benefit of clinical departments in cancer hospitals can help hospitals and departments to find out the shortcomings of operation,build the path of operating benefit improvement,and realize the connotation improvement and high-quality development of hospitals.