多孔钛腰椎融合器在不同入路椎间融合术中的生物力学性能

目的探究采用多孔融合器在不同入路腰椎融合术的生物力学性能。方法建立完整腰椎三维有限模型,通过实验方法获得多孔材料的力学参数。针对多孔融合器在前路腰椎椎间融合术(anterior lumbar interbody fusion, ALIF)、后路腰椎椎间融合术(posterior lumbar interbody fusion, PLIF)、经椎间孔腰椎椎间融合术(transforaminal lumbar interbody fusion, TLIF)和直接外侧椎体间融合术(direct lateral interbody fusion, DLIF)中的生物力学性能进行对比研究。结果在施行椎间融合术后,DLIF、ALIF模型预测的活动度(range of motion, ROM)和融合器应力明显低于PLIF、TLIF模型,DLIF、ALIF和TLIF模型预测的终板应力明显低于PILF模型。结论采用多孔融合器的DLIF模型显示出较优的生物力学性能,而且在临床过程中操作简单适于微创术式。DLIF手术具有更优的综合性能。     

新型关节突钉板系统联合单侧椎弓根螺钉固定的生物力学研究

目的 研究经椎间孔入路椎体间融合术(transforaminal lumbar interbody fusion,TLIF)结合新型关节突钉板系统(articular process fixation system,APFS)的腰椎稳定性.方法 在已验证的有限元模型L3～S1完整节段(模型A)上,模拟TLIF手术,建立...     

三种单纯腰椎椎间融合术加用双侧椎弓根螺钉内固定后生物力学比较的实验研究

目的比较前路椎间融合术(ALIF)、后路椎间融合术(PLIF)、椎间孔入路椎间融合术(TLIF)加用双侧椎弓根螺钉内固定后腰椎即刻稳定性的差异。方法选用15具新鲜小牛腰椎标本,模拟临床建立三种椎间融合术模型,在脊柱三维运动测试机上测试三种模型加用双侧椎弓根螺钉固定前后生物力学特性的变化。结果(1)与正常标本组相比,单纯椎间融合术的ALIF(Ⅰ)组的平均应变和应力明显增加;ALIF(Ⅰ)、PLIF(Ⅰ)、TLIF(Ⅰ)组的平均轴向刚度和水平剪切刚度分别下降28.3%、18.4%、11.5%(P<0.05)和21.6%、17.5%、5.9%(P<0 05);扭矩强度分别依次下降38.6%、49.1%、27.2%(P<0.05)。(2)附加双侧椎弓根螺钉固定后,与单纯椎间融合组的相应术式比较,ALIF(Ⅱ)、PLIF(Ⅱ)、TLIF(Ⅱ)三组的平均应变和应力分别减小了21.4%、12.3%、24.5%(P<0.05)和21.4%,22.3%,24.5%(P<0.05);平均轴向刚度和水平剪切刚度分别增加了87.8%、77.9%、75.9%(P<0.05)和60.6%、68.1%、63.1%(P<0.05);平均扭转强度分别增加了95.1%、110.9%、87.6%(P<0 05)。结论行单纯椎间融合术后,腰椎的稳定性较正常对照组均有明显下降,在加用双侧椎弓根螺钉内固定后能有效地提高其稳定性能。在三种椎间融合术中,TLIF的腰椎即刻稳定性能最优。     

TLIF术中最优化单侧螺钉植入和融合器放置的有限元分析

目的比较经单侧腰椎间孔椎体间融合(transforaminal lumbar interbody fusion,TLIF)中不同轴向植入角度椎弓根螺钉和不同放置位置融合器的生物力学特性。方法建立正常L3~5有限元模型,在验证其有效性基础上,在L4~5节段模拟后路双侧TLIF和4种不同组合类型椎弓根螺钉植入和融合器放置的单侧TLIF有限元重构模型,即:小角度植入椎弓根螺钉+对侧放置融合器(模型A)、小角度植入椎弓根螺钉+同侧放置融合器(模型B)、大角度植入椎弓根螺钉+同侧放置融合器(模型C)、大角度植入椎弓根螺钉+对侧放置融合器(模型D),分别比较4种重构模型在各种生理应力下的活动范围(range of the motion,ROM)以及螺钉、融合器与L4下终板界面的最大Von Mises应力差异。结果 4种单侧TLIF重构模型在融合节段(L4~5)ROM均较正常模型显著下降,但仍高于双侧TLIF重构模型。4种单侧TLIF重构模型稳定性比较,模型C下降最多,其在屈伸、侧屈和扭转应力下ROM分别减少约为正常模型的50.7%、89.9%和90.3%。螺钉和融合器与L4下终板界面最大Von Mises应力比较,相对于其他3组模型,模型C除了在同侧侧屈和扭转外的大部分应力下承受较小的应力。结论在单侧TLIF重构模型中选择大角度植入椎弓根螺钉和同侧放置融合器能够获得最佳的生物力学稳定性,通过缩小与双侧TLIF模型稳定性差异以减少断钉或融合器下沉的风险,值得临床推广运用。     

经皮椎间孔镜BEIS术治疗老年腰椎狭窄症合并腰椎滑脱患者的疗效评价

目的:探究经皮椎间孔镜BEIS(Broad easy immediate surgery,BEIS)术、椎间孔入路椎间融合术(Transforaminal lumbar interbody fusion,TLIF)治疗老年腰椎狭窄症合并腰椎滑脱患者的应用价值.方法:将武陟济民医院94例腰椎狭窄症合并腰椎滑脱患者随机分为TLIF组、BEIS组,各47例.对比手术指标、并发症情况、以视觉模拟量表(Visual analogue scales,VAS)、Oswestry功能障碍指数(Oswestry disability index,ODI)分别评估疼痛及腰椎功能.结果:BEIS组手术时间、住院时间短于TLIF组,术中出血量低于TLIF组(P<0.05);术后3、6个月BEIS组VAS评分、ODI评分均低于TLIF组(P<0.05).结论:与TLIF术比较,经皮椎间孔镜BEIS术治疗老年腰椎狭窄症合并腰椎滑脱患者能改善手术情况,缓解疼痛,改善腰椎功能,且不增加并发症风险.     

斜外侧腰椎间融合术后融合器沉降原因的研究进展

目的:总结斜外侧腰椎间融合术(OLIF)治疗腰椎退变性疾病患者术后融合器沉降的发生情况及原因。方法:以"斜外侧腰椎间融合术""腰椎间融合术""融合器""沉降""并发症""椎弓根螺钉""终板损伤""骨质疏松""微创融合术"和"oblique lateral interbody fusion""interlumbar fu...     

椎间融合与双侧经椎弓根经椎间盘螺钉置入后腰椎生物力学的有限元分析

背景：腰椎经椎弓根经椎间盘螺钉是一种新的微创脊柱内固定技术，与传统双侧椎弓根螺钉固定相比，单侧只需1枚螺钉固定1个节段，具有经济微创、操作便捷等优点。但目前探讨应用双侧经椎弓根经椎间盘螺钉联合改良经椎间孔入路腰椎椎间融合(transforaminal lumbar interbody fusion,TLIF)术式的研究仍很少见。目的：通过建立改良TLIF无内固定(cage alone)、改良TLIF联合双侧椎弓根螺钉内固定(cage+BPS)和改良TLIF联合双侧经椎弓根经椎间盘螺钉内固定(cage+BTPTDS) 3种有限元模型，评估改良TILF联合不同内固定对椎间融合器(cage)、内固定、椎间盘、下终板的应力分布及腰椎活动度的影响。方法：采集成人腰椎薄层CT扫描图像，通过Mimics、Geomagic和SolidWorks软件建立3种有限元模型：cage alone模型、cage+BPS模型和cage+BTPTDS模型。采用ANSYS Workbench模拟施加人体前屈、后伸、左侧弯、右侧弯、左侧旋转、右侧旋转6种不同运动载荷，计算3种模型cage及内固定、下终板、椎间盘应力分布...     

前路腰椎椎间融合的理论研究及其治疗进展

背景：前路腰椎椎间融合已成为一种椎间融合的标准技术, 广泛应用于椎体滑脱、椎间盘源性疼痛、腰椎失稳等病症的治疗。 目的：归纳总结前路椎间融合器的种类、前路腰椎椎间融合的临床应用及内固定器械种类等方面的研究进展。 方法：以“anterior lumbar interbody fusion”为检索词,检索PubMed数据库(1979年1月至2012年1月)。以“前路腰椎椎间融合术”为检索词,检索万方数据库(1979年1月至2012年1月)。文献语种限制为英文和中文。 结果与结论：计算机初检得到567篇文献,根据纳入排除标准,对39篇文献进行分析。近年来,前路腰椎椎间融合在临床应用方面及椎间融合器自外形到材料等都有很大发展,椎间融合率不断提高;多种内固定器械开始用于临床以增强前路融合的稳定性;小切口术式的临床应用,腹腔镜下手术的开展, 使手术趋向微创化。     

肾型n-HA/PA66腰椎间融合器在经椎间孔腰椎椎体间融合术中的有限元分析

目的　设计一种新型的“肾形”n-HA/PA66腰椎间融合器(cage),通过三维有限元分析,研究其在经椎间孔腰椎椎间融合术(TLIF)中的生物力学特性。 方法 建立正常人体L3-L5节段三维模型,模拟经椎间孔腰椎椎间融合术,采用有限元分析方法进行应力分析,比较肾型与子弹头型n-HA/PA66腰椎间融合器应力分布的差异。 结果　在前屈、后伸、左右旋转工况下两种不同cage的TLIF手术模型对比,子弹头型cage最大应力分别为32.8、32.8、31.4、31.3、32.8、34.2 MPa,肾型cage最大应力分别为13.2、11.4、10.9、10.1、11.7、11.1 MPa;而且肾型cage应力集中区域小于子弹头型cage。 结论　肾型n-HA/PA66腰椎间融合器固定的椎体应力分布小而均匀,理论上可有效降低cage沉降率。     

腰椎行椎间孔入路椎间融合术固定的有限元分析

目的 利用有限元方法分析经单侧椎间孔入路腰椎间融合术治疗腰椎退行性病变的临床可行性。方法 基于正常人L3~5节段的CT扫描数据,利用Mimics、Pro/E、ANSYS软件分别建立L3~5正常生理状态有限元模型、L4/5左单侧椎弓根螺钉内固定加椎间融合器模型(单侧TLIF)、L4/5双侧椎弓根螺钉内固定加椎间融合器模型(双侧TLIF)。在L3上表面施加500 N的人体重力和10 N?m力矩,模拟人体直立、前屈、后伸、左侧弯和右旋5种生理活动,观察不同工况时椎体、椎间盘、螺钉及融合器上变形及应力分布情况,比较两种固定方法力学性能上的差异。结果 各种工况下单侧TLIF、双侧TLIF的L3~5节段变形量均较生理状态模型减少,单侧TLIF、双侧TLIF模型均在后伸运动时融合器的应力达到最大值,且单侧TLIF模型椎弓根螺钉上的应力峰值在各种工况中均明显高于双侧TLIF,后伸工况时应力峰值达到463.39 MPa。结论 单侧TLIF可作为腰椎退变性疾病的一种固定方法,但应力峰值均明显高于双侧TLIF模型,故系统稳定性差于双侧TLIF模型,提示患者在康复过程中应减少后伸运动,以免发生手术失效或螺钉断裂。     

一种新型大鼠椎间融合模型的建立及评价

目的　建立一种新型的大鼠脊柱融合模型,并证实不同融合骨量对融合的影响。 方法　雄性SD大鼠60只,随机分成3组（n=20）,制备椎间融合模型,取双侧髂骨制成颗粒骨,A组0.3 cm3 颗粒骨植入待融合节段,B组0.2 cm3颗粒骨植入待融合节段,C组空白对照组,融合节段选择第1尾椎。3、6周后进行手触检查、X线评分,6周后组织学观察。 结果　3周时手触检查：A组融合率为10%、B组、C组无一例出现融合;6周：A组融合率为40%,B组为40%,C组未融合。X线评分系统,术后3周：A组（2.567±0.876）分,B组为（2.467±0.878）分,C组为（0.233±0.316）分;术后6周：A组为（3.233±1.218）分,B组为（3.267±1.235）分,C组为（0.467±0.322）分。组织学观察可见实验组已融合区有大量新生骨形成,C组可见纤维组织分布占大多数。 结论　本实验成功验证了一种新型大鼠脊柱融合模型。     

加压与不加压固定融合器对腰椎融合的影响

BACKGROUND: The posterior lumbar interbody fusion is one of the effective methods for the treatment of lumbar and sacral spine diseases. Most surgeons fix the cage by compressing the disc space in order to keep stability and prevent dislodgement. However, some surgeons think that the non-compression technique does favor for increasing of the disc and foraminal height and thus improving the clinical outcomes, and does not increase the risk of fusion shift.     

Cell fusion

Methods in Cell Science -     

Paramyxovirus fusion: real-time measurement of parainfluenza virus 5 virus-cell fusion

Although cell-cell fusion assays are useful surrogate methods for studying virus fusion, differences between cell-cell and virus-cell fusion exist. To examine paramyxovirus fusion in real time, we labeled viruses with fluorescent lipid probes and monitored virus-cell fusion by fluorimetry. Two parainfluenza virus 5 (PIV5) isolates (W3A and SER) and PIV5 containing mutations within the fusion protein (F) were studied. Fusion was specific and temperature-dependent. Compared to many low pH-dependent viruses, the kinetics of PIV5 fusion was slow, approaching completion within several minutes. As predicted from cell-cell fusion assays, virus containing an F protein with an extended cytoplasmic tail (rSV5 F551) had reduced fusion compared to wild-type virus (W3A). In contrast, virus-cell fusion for SER occurred at near wild-type levels, despite the fact that this isolate exhibits a severely reduced cell-cell fusion phenotype. These results support the notion that virus-cell and cell-cell fusion have significant differences.     

Rho GTPase activity modulates paramyxovirus fusion protein-mediated cell-cell fusion

The paramyxovirus fusion protein (F) promotes fusion of the viral envelope with the plasma membrane of target cells as well as cell-cell fusion. The plasma membrane is closely associated with the actin cytoskeleton, but the role of actin dynamics in paramyxovirus F-mediated membrane fusion is unclear. We examined cell-cell fusion promoted by two different paramyxovirus F proteins in three cell types in the presence of constitutively active Rho family GTPases, major cellular coordinators of actin dynamics. Reporter gene and syncytia assays demonstrated that expression of either Rac1(V12) or Cdc42(V12) could increase cell-cell fusion promoted by the Hendra or SV5 glycoproteins, though the effect was dependent on the cell type expressing the viral glycoproteins. In contrast, RhoA(L63) decreased cell-cell fusion promoted by Hendra glycoproteins but had little affect on SV5 F-mediated fusion. Also, data suggested that GTPase activation in the viral glycoprotein-containing cell was primarily responsible for changes in fusion. Additionally, we found that activated Cdc42 promoted nuclear rearrangement in syncytia.     

Elementary properties of spontaneous fusion of peptidergic vesicles: fusion pore gating

The release of hormones and neurotransmitters by regulated exocytosis requires the delivery of secretory vesicles to the plasma membrane, where they dock and become primed for fusion with the plasma membrane. Upon stimulation a fusion pore is formed through which cargo molecules diffuse out of the vesicle lumen into the extracellular space. After the cargo release the fusion pore either closes (kiss-and-run, transient exocytosis), fluctuates between an open and a closed state (for short times, fusion pore flickering, or for rather longer periods, 'pulsing pore') or expands irreversibly (full fusion exocytosis). In almost all secretory cells spontaneous secretion of vesicle cargo can be detected in the absence of stimulation. Spontaneous and stimulated exocytosis were thought to exhibit similar properties at elementary level, differing only in the probability of occurrence. However, recent studies indicate that spontaneous exocytosis differs from the stimulated one in many respects, therefore opening questions about the physiological role of spontaneous exocytosis. In this report we address the elementary properties of spontaneous and stimulated peptidergic vesicle discharge which appears to be modulated by fusion pore conductance (diameter) and fusion pore gating.     

部分可吸收椎间融合器用于山羊腰椎融合效果评价

目的评估部分可吸收椎间融合器(PBIFC)用于山羊腰椎融合的效果。方法采用16只中国青山羊行腰椎间融合术。每只动物于L_(2-5)3个椎间隙随机植入PBIFC、n HA/PA66 cage或1枚自体髂骨块。术后即刻及每4周拍摄腰椎侧位X线片。术后24周处死动物行CT扫描、组织学和生物力学评估。结果术后12周内X线评估显示,髂骨组和PBIFC组可观察到椎间融合,而n HA/PA66组在此期间内未见融合;术后24周CT评估显示PBIFC组的融合度评分高于n HA/PA66组,有统计学意义(0.05);生物力学测试显示PBIFC组平均刚度大于髂骨组,而髂骨组大于n HA/PA66组,均有显著性差异(0.05);组织学评估:PBIFC组在植骨区和椎间融合器边缘可见大量成熟的骨小梁,骨组织与材料表面已发生嵌合;髂骨组的植骨块与椎体间的新生骨小梁已改建为成熟的骨小梁;n HA/PA66组可见纤维骨痂形成。结论 PBIFC具有良好的生物力学特性,融合率高,可进一步用于临床试验研究。