In order to provide anatomical basis for transoral approach （TOA） in dealing with the ventro lesions of craniocervical junction, and the design and application of artificial atlanto-odontoid joint, microsurgical dis...In order to provide anatomical basis for transoral approach （TOA） in dealing with the ventro lesions of craniocervical junction, and the design and application of artificial atlanto-odontoid joint, microsurgical dissecting was performed on 8 fresh craniocervical specimens layer by layer through transoropharyngeal approach. The stratification of posterior pharyngeal wall, course of vertebral artery, adjacent relationship of atlas and axis and correlative anatomical parameters of replacement of artificial atlanto-odontoid joint were observed. Besides, 32 sets of atlanto-axial joint in adults＇ fresh bony specimens were measured with a digital caliper and a goniometer, including the width of bony window of anterior arch of atlas, the .width of bony window of axis vertebra, the distance between superior and inferior two atlas screw inserting points, the distance between two axis screw inserting points etc. It was found that the width of atlas and axis which could be exposed were 40.2±3.5 mm and 39.3±3.7 mm respectively. The width and height of posterior pharyngeal wall which could be exposed were 40.1±5.2 mm and 50.2±4.6 mm respectively. The distance between superior and inferior two atlas screw inserting points was 28.0±2.9 mm and 24.0±3.5 mm respectively, and the distance of bilateral axis screw inserting points was 18.0±1.2 mm. The operative exposure position through TOA ranged from inferior part of the clivus to the superior part of the C3 vertebral body. Posterior pharyngeal wall consisted of 5 layers and two interspaces： mucosa, submucosa, superficial muscular layer, anterior fascia of vertebrae, anterior muscular layer of vertebrae and posterior interspace of pharynx, anterior interspace of vertebrae. This study revealed that it had the advantages of short operative distance, good exposure and sufficient decompression in dealing with the ventro lesions from the upper cervical to the lower clivus through the TOA. The replacement of artificial atlanto-odontoid joint is suitable and feasible. The design of artificial atlanto-odontoid joint should be based on the above data.展开更多
Objective To investigate the clinical outcomes of trans-facet joints approach to treat thoracic degenerative disease with anterior compression.Methods From January 2003 to December 2009,22 patients with thoracic myelo...Objective To investigate the clinical outcomes of trans-facet joints approach to treat thoracic degenerative disease with anterior compression.Methods From January 2003 to December 2009,22 patients with thoracic myelopathy caused by展开更多
Joint clearance,as an important stochastic factor,can significantly deteriorate positioning and repeatability accuracies and lower assembly quality of a 6-DOF docking mechanism.Considering pose accuracy with tradition...Joint clearance,as an important stochastic factor,can significantly deteriorate positioning and repeatability accuracies and lower assembly quality of a 6-DOF docking mechanism.Considering pose accuracy with traditional error model that possesses inherent imprecision,both probabilistic and deterministic approaches based on forward kinematics are presented to analyze comprehensive pose error(CPE)in simulation.Results indicate an identical trend emerges for each CPE with both approaches,and both CPEs perform opposite variations as the moving platform upgrades.The findings provide theoretical reference for refinement of assembly quality evaluation of this mechanism.展开更多
The purpose of this review is to examine the validity of positive claims regarding the direct anterior approach(DAA) with a fracture table for total hip arthroplasty. Recent literature regarding the DAA was searched a...The purpose of this review is to examine the validity of positive claims regarding the direct anterior approach(DAA) with a fracture table for total hip arthroplasty. Recent literature regarding the DAA was searched and specific claims investigated including improved early outcomes, speed of recovery, component placement, dislocation rates, and complication rates. Recent literature is positive regarding the effects of total hip arthroplasty with the anterior approach. While the data is not definitive at present, patients receiving the anterior approach for total hip arthroplasty tend to recover more quickly and have improved early outcomes. Component placement with the anterior approach is more often in the "safe zone" than with other approaches. Dislocation rates tend to be less than 1% with the anterior approach. Complication rates vary widely in the published literature. A possible explanation is that the varianceis due to surgeon and institutional experience with the anterior approach procedure. Concerns remain regarding the "learning curve" for both surgeons and institutions. In conclusion, it is not a matter of should this approach be used, but how should it be implemented.展开更多
AIM: To determine hip joint center(HJC) location on hip arthroplasty population comparing predictive and functional approaches with radiographic measurements.METHODS: The distance between the HJC and the mid-pelvis wa...AIM: To determine hip joint center(HJC) location on hip arthroplasty population comparing predictive and functional approaches with radiographic measurements.METHODS: The distance between the HJC and the mid-pelvis was calculated and compared between the three approaches. The localisation error between the predictive and functional approach was compared using the radiographic measurements as the reference. The operated leg was compared to the non-operated leg.RESULTS: A significant difference was found for the distance between the HJC and the mid-pelvis when comparing the predictive and functional method. The functional method leads to fewer errors. A statistical difference was found for the localization error between the predictive and functional method. The functional method is twice more precise.CONCLUSION: Although being more individualized, the functional method improves HJC localization and should be used in three-dimensional gait analysis.展开更多
The objective of this work is to analyze the fatigue reliability of complex welded structures composed of multiple web-frame joints, accounting for correlation effects. A three-dimensional finite element model using t...The objective of this work is to analyze the fatigue reliability of complex welded structures composed of multiple web-frame joints, accounting for correlation effects. A three-dimensional finite element model using the 20-node solid elements is generated. A linear elastic finite element analysis was performed, hotspot stresses in a web-frame joint were analyzed and fatigue damage was quantified employing the S-N approach. The statistical descriptors of the fatigue life of a non-correlated web-frame joint containing several critical hotspots were estimated. The fatigue reliability of a web-frame joint wasmodeled as a series system of correlated components using the Ditlevsen bounds. The fatigue reliability of the entire welded structure with multiple web-frame joints, modeled as a parallel system of non-correlated web-frame joints was also calculated.展开更多
目的:探讨后路寰枢椎侧块关节cage植骨融合内固定术治疗难复性寰枢椎脱位的临床疗效,并与经口咽松解后路复位固定融合术进行疗效对比。方法:回顾性分析2018年1月~2022年8月我科采用后路寰枢椎侧块关节cage植骨融合内固定术(23例,cage组...目的:探讨后路寰枢椎侧块关节cage植骨融合内固定术治疗难复性寰枢椎脱位的临床疗效,并与经口咽松解后路复位固定融合术进行疗效对比。方法:回顾性分析2018年1月~2022年8月我科采用后路寰枢椎侧块关节cage植骨融合内固定术(23例,cage组)与经口咽松解后路复位固定融合术(25例,对照组)治疗的难复性寰枢椎脱位患者的临床资料,cage组男8例,女15例,年龄9~79岁(48.35±14.38岁);对照组男6例,女19例,年龄21~69岁(47.84±13.51岁)。记录两组患者手术时间、术中出血量、住院时间及并发症情况,术前、术后及末次随访时使用JOA评分评估患者神经功能状态,测量术前、术后及末次随访时的寰齿间距(atlantodental interval,ADI)、齿状突顶点距离Chamberlain线的垂直距离(vertical distance from odon to idprocess to Chamberlain′s line,DOCL)、延髓颈髓角(cervicomedullary angle,CMA)、斜坡枢椎角(clivus-axial angle,CAA),评估寰枢椎复位情况。评估侧块关节cage及后方植骨融合情况。结果:所有患者内固定位置良好,减压充分复位满意,症状均明显缓解,未出现椎动脉损伤和脊髓损伤加重。cage组手术时间133.04±34.04min、术中出血量119.13±54.77mL、住院时间14.74±6.10d,均明显短于或少于对照组(253.20±53.98min、181.20±45.40mL、23.96±5.47d)。cage组术前JOA、ADI、DOCL、CMA、CAA分别为6.33±1.13分、7.31±3.05mm、9.47±3.32mm、122.89°±12.58°、122.02°±12.50°,术后分别为13.04±2.17分、2.18±0.67mm、0.89±1.00mm、148.81°±5.43°、146.70°±9.32°,末次随访时分别为14.89±1.17分、2.09±0.69mm、0.83±0.86mm、149.10°±5.11°、146.89°±8.95°;对照组术前JOA、ADI、DOCL、CMA、CAA分别为6.76±1.21分、7.70±0.97mm、10.56±1.99mm、121.53°±4.87°、123.77°±8.95°,术后分别为13.26±1.32分、1.89±0.50mm、1.13±1.08mm、151.40°±6.15°、149.86°±5.58°,末次随访时分别为15.02±0.88分、1.87±0.44mm、0.87±1.39mm、149.48°±4.06°、149.94°±6.61°,两组术后及末次随访JOA、ADI、DOCL、CMA及CAA均较术前明显改善(P<0.05),术后JOA评分与末次随访相比存在统计学差异(P<0.05),但ADI、DOCL、CMA及CAA无统计学差异(P>0.05)。cage组仅1例切口感染;对照组3例切口感染(口咽2例,后路1例),1例脑脊液漏。两组随访期间内固定在位稳定,末次随访植骨均达到骨性融合,cage组关节间隙高度无丢失。结论:难复性寰枢椎脱位采用后路寰枢椎侧块关节cage植骨融合内固定术与经口咽松解后路复位固定融合术相比疗效相当,但增加了植骨融合位点,能更有效融合,避免了经口手术,减少了手术时间、术中出血量、住院时间及并发症的发生。展开更多
文摘In order to provide anatomical basis for transoral approach （TOA） in dealing with the ventro lesions of craniocervical junction, and the design and application of artificial atlanto-odontoid joint, microsurgical dissecting was performed on 8 fresh craniocervical specimens layer by layer through transoropharyngeal approach. The stratification of posterior pharyngeal wall, course of vertebral artery, adjacent relationship of atlas and axis and correlative anatomical parameters of replacement of artificial atlanto-odontoid joint were observed. Besides, 32 sets of atlanto-axial joint in adults＇ fresh bony specimens were measured with a digital caliper and a goniometer, including the width of bony window of anterior arch of atlas, the .width of bony window of axis vertebra, the distance between superior and inferior two atlas screw inserting points, the distance between two axis screw inserting points etc. It was found that the width of atlas and axis which could be exposed were 40.2±3.5 mm and 39.3±3.7 mm respectively. The width and height of posterior pharyngeal wall which could be exposed were 40.1±5.2 mm and 50.2±4.6 mm respectively. The distance between superior and inferior two atlas screw inserting points was 28.0±2.9 mm and 24.0±3.5 mm respectively, and the distance of bilateral axis screw inserting points was 18.0±1.2 mm. The operative exposure position through TOA ranged from inferior part of the clivus to the superior part of the C3 vertebral body. Posterior pharyngeal wall consisted of 5 layers and two interspaces： mucosa, submucosa, superficial muscular layer, anterior fascia of vertebrae, anterior muscular layer of vertebrae and posterior interspace of pharynx, anterior interspace of vertebrae. This study revealed that it had the advantages of short operative distance, good exposure and sufficient decompression in dealing with the ventro lesions from the upper cervical to the lower clivus through the TOA. The replacement of artificial atlanto-odontoid joint is suitable and feasible. The design of artificial atlanto-odontoid joint should be based on the above data.
文摘Objective To investigate the clinical outcomes of trans-facet joints approach to treat thoracic degenerative disease with anterior compression.Methods From January 2003 to December 2009,22 patients with thoracic myelopathy caused by
基金supported by the National Defense Basic Scientific Research Program(No.A0320110019)the Shanghai Science and Technology Innovation Action Plan(No.11DZ1120800)
文摘Joint clearance,as an important stochastic factor,can significantly deteriorate positioning and repeatability accuracies and lower assembly quality of a 6-DOF docking mechanism.Considering pose accuracy with traditional error model that possesses inherent imprecision,both probabilistic and deterministic approaches based on forward kinematics are presented to analyze comprehensive pose error(CPE)in simulation.Results indicate an identical trend emerges for each CPE with both approaches,and both CPEs perform opposite variations as the moving platform upgrades.The findings provide theoretical reference for refinement of assembly quality evaluation of this mechanism.
文摘The purpose of this review is to examine the validity of positive claims regarding the direct anterior approach(DAA) with a fracture table for total hip arthroplasty. Recent literature regarding the DAA was searched and specific claims investigated including improved early outcomes, speed of recovery, component placement, dislocation rates, and complication rates. Recent literature is positive regarding the effects of total hip arthroplasty with the anterior approach. While the data is not definitive at present, patients receiving the anterior approach for total hip arthroplasty tend to recover more quickly and have improved early outcomes. Component placement with the anterior approach is more often in the "safe zone" than with other approaches. Dislocation rates tend to be less than 1% with the anterior approach. Complication rates vary widely in the published literature. A possible explanation is that the varianceis due to surgeon and institutional experience with the anterior approach procedure. Concerns remain regarding the "learning curve" for both surgeons and institutions. In conclusion, it is not a matter of should this approach be used, but how should it be implemented.
基金Canadian Institute of Health Science(CIHR)and Zimmer,Warsaw,United States
文摘AIM: To determine hip joint center(HJC) location on hip arthroplasty population comparing predictive and functional approaches with radiographic measurements.METHODS: The distance between the HJC and the mid-pelvis was calculated and compared between the three approaches. The localisation error between the predictive and functional approach was compared using the radiographic measurements as the reference. The operated leg was compared to the non-operated leg.RESULTS: A significant difference was found for the distance between the HJC and the mid-pelvis when comparing the predictive and functional method. The functional method leads to fewer errors. A statistical difference was found for the localization error between the predictive and functional method. The functional method is twice more precise.CONCLUSION: Although being more individualized, the functional method improves HJC localization and should be used in three-dimensional gait analysis.
文摘The objective of this work is to analyze the fatigue reliability of complex welded structures composed of multiple web-frame joints, accounting for correlation effects. A three-dimensional finite element model using the 20-node solid elements is generated. A linear elastic finite element analysis was performed, hotspot stresses in a web-frame joint were analyzed and fatigue damage was quantified employing the S-N approach. The statistical descriptors of the fatigue life of a non-correlated web-frame joint containing several critical hotspots were estimated. The fatigue reliability of a web-frame joint wasmodeled as a series system of correlated components using the Ditlevsen bounds. The fatigue reliability of the entire welded structure with multiple web-frame joints, modeled as a parallel system of non-correlated web-frame joints was also calculated.
文摘目的:探讨后路寰枢椎侧块关节cage植骨融合内固定术治疗难复性寰枢椎脱位的临床疗效,并与经口咽松解后路复位固定融合术进行疗效对比。方法:回顾性分析2018年1月~2022年8月我科采用后路寰枢椎侧块关节cage植骨融合内固定术(23例,cage组)与经口咽松解后路复位固定融合术(25例,对照组)治疗的难复性寰枢椎脱位患者的临床资料,cage组男8例,女15例,年龄9~79岁(48.35±14.38岁);对照组男6例,女19例,年龄21~69岁(47.84±13.51岁)。记录两组患者手术时间、术中出血量、住院时间及并发症情况,术前、术后及末次随访时使用JOA评分评估患者神经功能状态,测量术前、术后及末次随访时的寰齿间距(atlantodental interval,ADI)、齿状突顶点距离Chamberlain线的垂直距离(vertical distance from odon to idprocess to Chamberlain′s line,DOCL)、延髓颈髓角(cervicomedullary angle,CMA)、斜坡枢椎角(clivus-axial angle,CAA),评估寰枢椎复位情况。评估侧块关节cage及后方植骨融合情况。结果:所有患者内固定位置良好,减压充分复位满意,症状均明显缓解,未出现椎动脉损伤和脊髓损伤加重。cage组手术时间133.04±34.04min、术中出血量119.13±54.77mL、住院时间14.74±6.10d,均明显短于或少于对照组(253.20±53.98min、181.20±45.40mL、23.96±5.47d)。cage组术前JOA、ADI、DOCL、CMA、CAA分别为6.33±1.13分、7.31±3.05mm、9.47±3.32mm、122.89°±12.58°、122.02°±12.50°,术后分别为13.04±2.17分、2.18±0.67mm、0.89±1.00mm、148.81°±5.43°、146.70°±9.32°,末次随访时分别为14.89±1.17分、2.09±0.69mm、0.83±0.86mm、149.10°±5.11°、146.89°±8.95°;对照组术前JOA、ADI、DOCL、CMA、CAA分别为6.76±1.21分、7.70±0.97mm、10.56±1.99mm、121.53°±4.87°、123.77°±8.95°,术后分别为13.26±1.32分、1.89±0.50mm、1.13±1.08mm、151.40°±6.15°、149.86°±5.58°,末次随访时分别为15.02±0.88分、1.87±0.44mm、0.87±1.39mm、149.48°±4.06°、149.94°±6.61°,两组术后及末次随访JOA、ADI、DOCL、CMA及CAA均较术前明显改善(P<0.05),术后JOA评分与末次随访相比存在统计学差异(P<0.05),但ADI、DOCL、CMA及CAA无统计学差异(P>0.05)。cage组仅1例切口感染;对照组3例切口感染(口咽2例,后路1例),1例脑脊液漏。两组随访期间内固定在位稳定,末次随访植骨均达到骨性融合,cage组关节间隙高度无丢失。结论:难复性寰枢椎脱位采用后路寰枢椎侧块关节cage植骨融合内固定术与经口咽松解后路复位固定融合术相比疗效相当,但增加了植骨融合位点,能更有效融合,避免了经口手术,减少了手术时间、术中出血量、住院时间及并发症的发生。
