经寰枢关节间隙螺钉和寰椎椎板钩内固定的力学稳定性

目的评价双侧经寰枢关节间隙螺钉和寰椎椎板钩内固定的力学稳定性。方法将6具新鲜尸体颈椎标本（包括枕骨基底部和C1-C4颈椎节段）置于1．5Nm载荷下，测量C1，2节段的三维运动范围（range of motion，ROM）。标本依Gallie内固定、双侧经寰枢关节间隙螺钉和Gallie内固定、双侧经寰枢关节间隙螺钉内固定、双侧经寰枢关节间隙螺钉和寰椎椎板钩内固定、双侧寰椎侧块螺钉和枢椎椎弓根螺钉内固定的顺序实施固定，每次固定后测量三维运动范围。结果包含经寰枢关节间隙螺钉的内固定组在旋转和侧屈方向上具有最小的ROM，其中双侧经寰枢关节间隙螺钉和寰椎椎板钩内固定组在屈伸运动方向上也具有最小的ROM。寰椎侧块螺钉和枢椎椎弓根螺钉内固定组在旋转方向上ROM大于单纯经寰枢关节间隙螺钉内固定组，但在侧屈和屈伸方向上接近经寰枢关节间隙螺钉，差异无统计学意义；其在侧屈和旋转方向上ROM均小于Gallie内固定组，差异有统计学意义。结论双侧经寰枢关节间隙螺钉和寰椎椎板钩“三点”内固定具有最强的生物力学稳定性。虽然双侧寰椎侧块螺钉和枢椎椎弓根螺钉内固定在生物力学稳定性上不及“三点”内固定，但明显优于Gallie内固定。     

三种后路寰枢椎融合术的离体生物力学研究

目的 通过离体生物力学研究方法,比较3种后路寰枢椎融合技术的力学稳定性.方法 将8具新鲜尸体的颈椎标本(C1～4)置于1.5 Nm载荷下,测量C1、2关节的三维运动范围(ROM).每具标本依双侧经寰枢关节间隙螺钉结合Gallie内固定术、双侧经寰枢关节间隙螺钉结合寰椎椎板钩内固定术、双侧寰椎侧块螺钉结合枢椎椎弓根螺钉内固定术的顺序实施固定,每次固定后测量三维运动范围.结果 包含经寰枢关节间隙螺钉的内固定组在旋转和侧屈方向上具有最小的ROM角度,其中新型的双侧经寰枢关节间隙螺钉结合寰椎椎板钩内固定组在前屈后伸运动方向上也具有最小ROM角度.寰椎侧块螺钉结合枢椎椎弓根螺钉内固定组在旋转方向上ROM角度显著大于单独经寰枢关节螺钉内固定组,但在侧屈和前屈后伸方向上ROM角度近似于经寰枢关节间隙螺钉,差异无统计学意义.结论 双侧经寰枢关节间隙螺钉结合寰椎椎板钩内固定术具有最强的生物力学稳定性;双侧寰椎侧块螺钉结合枢椎椎弓根螺钉内固定术与双侧经寰枢关节间隙螺钉结合寰椎椎板钩内固定技术比较,具有相似的力学稳定性.     

新型寰枢椎固定组合的生物力学测试

[目的]采用尸体标本测试枢椎椎板螺钉联合新型寰椎椎板钩内固定系统的生物力学稳定性.[方法]采用6具新鲜尸体颈椎标本(C0-3),分别测试完整标本模型(完整组)、寰枢椎不稳标本模型(失稳组)、双侧寰枢椎经关节螺钉联合Gallie固定植骨模型(bTFS+G组)、双侧寰枢椎经关节螺钉联合新型寰椎椎板钩固定植骨模型(bTFS+...     

两种寰枢椎后路内固定系统的三维有限元分析

[目的]运用有限元方法评价寰枢椎经关节螺钉联合椎板钩内固定和寰枢椎椎弓根螺钉内固定生物力学稳定性和安全性。[方法]运用有限元软件建立寰枢椎经关节螺钉联合椎板钩和寰枢椎椎弓根螺钉两种内固定系统的有限元模型,并加载到寰枢椎不稳的有限元模型上,进行计算和分析,得出各个有限元模型的活动度(ROM),并提取内固定有限元模型的应力云图。[结果]寰枢椎经关节螺钉联合椎板钩内固定的活动度要略小于寰枢椎椎弓根螺钉内固定。在屈和伸的工况下,寰枢椎经关节螺钉联合椎板钩内固定产生应力值较大,主要集中在螺钉根部和经关节部位;在后伸工况下,寰枢椎椎弓根螺钉内固定产生应力较大,主要集中在螺钉的根部和连接棒。[结论]寰枢椎经关节螺钉联合椎板钩内固定的稳定性略好于寰枢椎椎弓根螺钉内固定。寰枢椎经关节螺钉联合椎板钩内固定在螺钉经关节部位和螺钉根部易产生断钉,而寰枢椎椎弓根螺钉内固定在螺钉根部和连接棒处易产生断钉。     

寰椎一体式椎板钩与枢椎椎板钉组合应用于非对称内固定生物力学研究

目的本文报道设计一新型寰枢椎内固定组合,并在尸体标本进行生物力学试验,有一定的临床指导意义。方法将6具新鲜尸体颈椎标本置于2Nm载荷下,运用脊柱三维运动测量系统测量C1-2节段的三维运动范围(Range Of Motion,ROM),并将之进行两两对比。实验依完整组、失稳组、双侧寰椎侧块螺钉联合枢椎椎弓根螺钉内固定(Harms技术)组、寰椎侧块螺钉联合单侧枢椎椎板螺钉+对侧枢椎椎弓根螺钉固定组、一侧寰椎一体式椎板钩+枢椎椎板钉联合对侧寰椎侧块螺钉+枢椎椎弓根螺钉内固定组的顺序进行。结果失稳组ROM较完整组显著增加,内固定后ROM显著减小,三种内固定组中:寰椎侧块螺钉联合单侧枢椎椎板螺钉+对侧枢椎椎弓根螺钉固定组在旋转和侧屈方向上具有最小的ROM,双侧寰椎侧块螺钉联合枢椎椎弓根螺钉内固定组在屈伸运动方向上有最小的R0M。一侧寰椎一体式椎板钩+枢椎椎板钉联合对侧寰椎侧块螺钉+枢椎椎弓根螺钉内固定组ROM在旋转、侧屈以及屈伸方向上均较另外两组大,但差异均无统计学意义。结论寰椎一体式椎板钩与枢椎椎板钉组合非对称内固定可提供良好的生物力学稳定性。     

新型寰椎钩棒及椎板钩联合枢椎椎弓根螺钉内固定的生物力学

目的 评价自行研制的寰椎后弓环抱钩棒及椎板钩联合枢椎椎弓根螺钉内固定系统的生物力学稳定性,为临床应用提供实验依据. 方法 6具新鲜尸体枕颈部标本,采用脊柱三维运动试验机依次对其齿状突切断后(A组)、寰椎椎板钩联合枢椎椎弓根螺钉内固定(B组)、自制寰椎钩棒及椎板钩联合枢椎椎弓根螺钉内固定(C组)、寰椎椎弓根螺钉联合枢椎椎弓根螺钉内固定(D组)等4种状态进行三维运动范围测试;分析比较新型寰枢椎后路内固定系统的稳定性. 结果 B组后伸平均ROM明显大于C、D组,差异均有统计学意义(P＜0.05);C、D组后伸平均ROM差异无统计学意义(P＞0.05);而B、C、D组间在其他角度ROM(前屈、侧屈、旋转)差异均无统计学意义(P＞0.05).结论 采用自制寰椎后弓钩棒及椎板钩联合枢椎椎弓根螺钉进行内固定,可为失稳的寰枢关节提供良好的即刻和较长期稳定性.     

寰椎椎板钩联合枢椎椎弓根螺钉内固定的力学稳定性评价

目的 评价寰椎椎板钩联合枢椎椎弓根螺钉内固定的生物力学稳定性.方法 取6具新鲜尸体颈椎标本置于1.5 N·m载荷下,测量C_(1-2)节段的三维运动范围(ROM).标本按随机顺序,依次行完整状态(完整状态组)、不稳状态(齿状突周围韧带切除,为不稳状态组)、经寰枢关节间隙螺钉联合Gallic内固定(固定A组)、寰椎椎板钩联合枢椎椎弓根螺钉内固定(固定B组)、寰枢椎椎弓根螺钉内固定(固定C组)5种状态下的三维ROM值测量.比较各组标本的屈伸、侧屈、旋转ROM值.结果 完整状态组、不稳状态组、固定A、B、C组的平均屈伸ROM值分别为17.78°、30.69°、2.25°、2.93°、2.73°,组间比较差异有统计学意义(F=216.69,P=0.000);平均侧屈ROM值分别为9.56°、17.18°、1.91°、2.30°、2.05°,组间比较差异有统计学意义(F=122.75,P=0.000);平均旋转ROM值分别为44.19°、57.30°、1.22°、2.88°、2.07°,组间比较差异有统计学意义(F=154.54,P=0.000).固定A、B、C组较完整状态组和不稳状态组各个方向的ROM值均明显减少,差异均有统计学意义(P<0.05),但固定A、B、C组之间符个方向的ROM值比较差异均无统计学意义(P>0.05).结论 寰椎椎板钩联合枢椎椎弓根螺钉内固定可提供与经寰枢关节间隙螺钉联合Gallic内固定和寰枢椎椎弓根螺钉内固定相当的力学稳定性.在以上两种方法无法实施时,可作为一种安全的替代.     

寰枢椎后路两种四点内固定技术三维稳定性生物力学评价

寰枢椎后路双侧经关节螺钉加Apo-fix椎板夹固定(简称经典四点固定技术)治疗寰枢椎不稳症,具有可靠的力学稳定性,且术后的骨性融合率较高[1].我们通过测试Magerl螺钉+C1双侧椎板钩组合C2椎板交叉螺钉固定(简称改良四点内固定技术)三维运动范围,并比较两种四点内固定方式的生物力学稳定性,并对改良四点内固定技术机制作初步探讨.     

寰椎侧块-枢椎椎板螺钉固定的有限元分析

目的:建立寰椎侧块-枢椎椎板螺钉固定的三维有限元模型并进行有限元分析,探讨其生物力学特性。方法:通过CT扫描获取1例健康成年男性寰枢椎图像信息,应用VTK软件及ABAQUS软件构建寰椎侧块-枢椎椎板螺钉固定的三维有限元模型,观察中立、前屈/后伸、侧弯、旋转、前后平移等载荷下固定系统的应力变化,分析寰枢侧块-枢椎椎板螺钉固定系统的生物力学特性。结果:所建立的有限元模型逼真地描绘了寰椎侧块-枢椎椎板螺钉固定系统的结构特点,共包含183363个节点(椎骨130982个,螺钉52381个),116082个单元(椎骨83776个,螺钉32306个)。在不同运动状态下,螺钉应力分布主要集中在螺钉置入骨质部分的根部周围和钉棒连接处。前屈载荷时,连接棒从头端至尾端的应力逐步减小,在寰椎侧块螺钉的钉棒连接处应力最大;其他载荷下连接棒应力分布从头端至尾端逐步增大,至枢椎椎板螺钉的钉棒连接处达到最大。后伸和旋转载荷下,螺钉存在明显的高应力区,各螺钉的应力最大值大于其他运动状态。结论:寰椎侧块-枢椎椎板螺钉固定系统固定时各螺钉在颈椎旋转及后伸时所受应力明显增加,术后应避免颈椎过度旋转及后伸,以减少螺钉松动和断裂的发生。     

双侧寰椎椎板挂钩及经寰枢椎关节间隙螺钉固定术

寰枢椎后路融合术是稳定上颈椎最常用的手术方式之一。目前临床上常用的内固定方法包括钢丝捆扎技术（Gallie技术和Brooks技术）、椎板夹技术、经C1～C2关节螺钉技术（Magrel技术）、C1～C2椎弓根螺钉技术等。研究表明，上述每项单一技术均有其不足和缺陷。2004年2月至2004年12月，我们采用一种新的寰枢椎后路内固定术——双侧寰椎椎板挂钩及经寰枢椎关节间隙螺钉固定术及自体骼骨植骨治疗了16例寰枢椎不稳患者，现将初步临床应用情况报道如下。     

A finite element investigation of upper cervical instrumentation.

STUDY DESIGN: The finite element technique was used to predict changes in biomechanics that accompany the application of a novel instrumentation system designed for use in the upper cervical spine. OBJECTIVE: To determine alterations in joint loading, kinematics, and instrumentation stresses in the craniovertebral junction after application of a novel instrumentation system. Specifically, this design was used to assess the changes in these parameters brought about by two different cervical anchor types: C2 pedicle versus C2-C1 transarticular screws, and unilateral versus bilateral instrumentation. SUMMARY OF BACKGROUND DATA: Arthrodesis procedures can be difficult to obtain in the highly mobile craniovertebral junction. Solid fusion is most likely achieved when motion is eliminated. Biomechanical studies have shown that C1-C2 transarticular screws provide good stability in craniovertebral constructs; however, implantation of these screws is accompanied by risk of vertebral artery injury. A novel instrumentation system that can be used with transarticular screws or with C2 pedicle screws has been developed. This design also allows for unilateral or bilateral implantation. However, the authors are unaware of any reports to date on the changes in joint loading or instrumentation stresses that are associated with the choice of C2 anchor or unilateral/bilateral use. METHODS: A ligamentous, nonlinear, sliding contact, three-dimensional finite element model of the C0-C1-C2 complex and a novel instrumentation system was developed. Validation of the model has been previously reported. Finite element models representing combinations of cervical anchor type (C1-C2 transarticular screws vs. C2 pedicle screws) and unilateral versus bilateral instrumentation were evaluated. All models were subjected to compression with pure moments in either flexion, extension, or lateral bending. Kinematic reductions with respect to the intact (uninjured and without instrumentation) case caused by instrumentation use were reported. Changes in loading profiles through the right and left C0-C1 and C1-C2 facets, transverse ligament-dens, and dens-anterior ring of C1 articulations were calculated by the finite element model. Maximum von Mises stresses within the instrumentation were predicted for each model variant and loading scenario. RESULTS: Bilateral instrumentation provided greater motion reductions than the unilateral instrumentation. When used bilaterally, C2 pedicle screws approximate the kinematic reductions and instrumentation stresses (except in lateral bending) that are seen with C1-C2 transarticular screws. The finite element model predicted that the maximum stress was always in the region in which the plate transformed into the rod. CONCLUSIONS: To the best of the authors' knowledge, this is the first report of predicting changes in loading in the upper cervical spine caused by instrumentation. The most significant conclusion that can be drawn from the finite element model predictions is that C2 pedicle screw fixation provides the same relative stability and instrumentation stresses as C1-C2 transarticular screw use. C2 pedicle screws can be a good alternative to C2-C1 transarticular screws when bilateral instrumentation is applied.     

枢椎椎板螺钉在上颈椎后路固定术中的应用

目的探讨枢椎椎板螺钉固定术应用于上颈椎后路融合内固定术中的可行性。方法回顾性分析本院2012年1月—2014年12月在上颈椎后路融合固定术中采用枢椎椎板螺钉固定的19例患者资料,术中根据枢椎椎弓根是否存在缺如、细小等情况,选择置入双侧枢椎椎板螺钉或单侧枢椎椎板螺钉并对侧椎弓根螺钉,联合枕骨板螺钉和/或寰椎侧块螺钉。15例上颈椎畸形患者均有不同程度脊髓功能损害表现,日本骨科学会(JOA)评分为5~15分,平均11.5分。4例外伤性寰枢椎骨折患者有后颈部疼痛及活动障碍,疼痛视觉模拟量表(VAS)评分为2~7分,平均4.5分。术后复查患者影像学资料,观察内固定位置及植骨融合情况。结果所有手术顺利完成,未发生椎动脉、脊髓等损伤。术后复查CT,显示所有枢椎椎板螺钉位置良好,均未突破内侧皮质骨。随访时X线、CT示螺钉位置良好,无松动及断钉。所有患者术后12个月植骨均融合,上颈椎畸形患者神经功能均有不同程度改善,JOA评分为13~17分,平均15.3分。外伤性寰枢椎骨折患者颈部疼痛及活动障碍明显改善,VAS评分为0~2分,平均1.0分。结论枢椎椎板螺钉固定在上颈椎后路固定手术中方法简单安全、效果良好,对于无法行枢椎椎弓根螺钉固定的患者,枢椎椎板螺钉固定是一种安全有效的替代方法。     

Safety of atlantoaxial fusion using laminar and transarticular screws combined with an atlas hook in a patient with unilateral vertebral artery occlusion (case report)

Objective and importance  A disadvantage of transarticular and C2 pedicle screws is vertebral artery (VA) injury as a result of screw misplacement. If unilateral occlusion of the VA is present, VA injury of the dominant side will cause fatal complications as a result of collateral flow insufficiency. Several authors have recently reported the usefulness of C2 laminar screws because of their safety on VA injury. We used transarticular and C2 laminar screws combined with the atlas hook in a patient with C1-2 instability and unilateral VA occlusion, in order to reduce the risk of further VA injury. Clinical presentation  A 64-year-old woman with rheumatoid atlantoaxial subluxation complained of cervical myelopathy and neck pain. Preoperative MR angiography showed a left side VA occlusion. Technique  The patient underwent atlantoaxial, posterior fusion using a transarticular screw on the side of the occlusion and a C2 laminar screw on the dominant side combined with a bilateral atlas hook. The transarticular screw was inserted using a navigation system and image intensifier, and the laminar screw was inserted free hand. Bone grafting from the iliac crest was performed. Conclusion  Transarticular and C2 laminar screws fixation combined with the atlas hook in a patient with unilateral VA occlusion is a useful technique, in order to reduce the risk of further VA injury.     

Bilateral atlas laminar hook combined with transarticular screw fixation for an unstable bursting atlantal fracture

Introduction  The unstable atlas burst fracture (“Jefferson fracture”) is a fracture of the anterior and posterior atlantal arch with rupture of the transverse atlantal ligament and an incongruence of the atlanto-occipital and the atlanto-axial joint facets. The posterior atlantoaxial fusion is frequently used to reconstruct the stability of atlantoaxial joint. Conventional posterior atlantoaxial fixations are associated with high rates of pseudoarthrosis and chronic atlantoaxial instability. As a modified three-point fixation the bilateral C1-2 transarticular screws combined with C1 laminar hook and bone grafts can provide best biomechanical stability, but no standard protocol has been reported for the use of this fusion technique. A retrospective review of clinical series should be conducted to evaluate the clinical outcome of bilateral atlas laminar hook combined with transarticular screw fixation for unstable bursting atlantal fracture. Materials and methods  From March 2002 to March 2006, there were total 12 cases of unstable atlantal bursting fractures, 10 males and 2 females, age ranging 18–54, with mean of 36 years old. All patients were operated on posterior atlantoaxial fusion using bilateral atlas laminar hook combined with transarticular screw fixation after atlantoaxial joint were reduced and followed up for 12–24 months. The medical records and radiographs of the 12 patients were reviewed. Each patient underwent a complete cervical radiograph series including lateral flexion-extension view and a computed topographic scan. The Frankel grades and ASIA scores were applied to assess the neurologic status. Results  In all patients, a good bony fusion of the atlanto-axial segment was achieved. All patients showed significant improvement of the neurologic defect and no instability on their follow-up plain radiographs and computerized tomography in follow-up interval. Conclusions  For the patients who suffer from the unstable bursting atlantal fracture, the nonoperative methods could carry some clinical complications including infection, nerve injury, etc. and is frequently failure, Posterior atlantoaxial fusion using bilateral atlas laminar hook combined with transarticular screw fixation is an effective treatment. Xiang Guo and Bin Ni contributed equally to the article.     

Biomechanical comparison of five different atlantoaxial posterior fixation techniques

STUDY DESIGN: Five different reconstructions of the atlantoaxial complex were biomechanically compared in vitro in a nondestructive test. OBJECTIVES: To determine whether non-bone graft-dependent one-point fixation affords stability levels equivalent to three-point reconstructions. SUMMARY OF BACKGROUND DATA: Previous investigations have demonstrated that three-point fixation, using bilateral transarticular screws in combination with posterior wiring, provide the most effective resistance to minimize motion around C1-C2. However, placement of transarticular screws is technically demanding. Posterior wiring techniques affording one-point fixation have failure rates of approximately 15%, with failure considered to be secondary to structural bone graft failures. One-point, non-bone graft-dependent fixations have not been tested. METHODS: Eight human cervical specimens, C0-C3 were loaded nondestructively. Unconstrained three-dimensional segmental motion was measured. The reconstructions tested were two one-point fixations, one two-point fixation, and two three-point fixations. RESULTS: Under axial rotation two and three-point reconstructions provided better stiffness than the one-point reconstructions (P < 0.05). During flexion-extension, higher stiffness levels were observed in one- and three-point fixations when compared with the intact spine (P < 0.05). In lateral bending no significant differences were observed among the six groups, although the trend was that reconstructions including transarticular screws provided greater stability than one-point fixations. CONCLUSION: The current findings substantiate the use of three-point fixation as the treatment of choice for C1-C2 instability. [l: atlantoaxial fixation, biomechanics, cervical spine, instability, spinal instrumentation, transarticular screws]     

前路经寰枢关节螺钉内固定生物力学性能的有限元分析

目的:通过有限元分析的方法评估前路经寰枢关节螺钉内固定的生物力学性能。方法:选择一名21岁健康男性志愿者,采用螺旋CT对枕骨底到C3椎体进行层厚1mm的薄层扫描,利用MIMICS 13.0软件、Freeform Plus软件及ANSYS 9.0软件,建立正常上颈椎有限元模型。去除模型中横韧带的所有单元模拟寰枢关节不稳,以枢椎前弓下缘与枢椎椎体侧缘交界点上方4mm处为进钉点,经寰枢关节分别向两寰椎侧块外上角中部置钉,最终建立前路经寰枢关节螺钉内固定治疗寰枢关节不稳的有限元模型。给予模型分别施加前屈、后伸、侧屈、旋转四种生理载荷,观察不同载荷下螺钉的三维运动范围与应力变化,分析前路经寰枢关节螺钉内固定的生物力学性能。结果:前路经寰枢关节螺钉内固定在不同载荷下三维运动范围均较小,但前屈、后伸状态下三维运动范围(0.72°,1.08°)明显大于侧屈、旋转状态(0.39°,0.32°)。不同状态下应力集中区域均为螺钉经寰枢关节部位,最大应力值为10.58×107Pa,出现在后伸状态。结论:前路经寰枢关节螺钉内固定具有可靠的生物力学性能,在侧屈、旋转状态下的力学性能优于前屈后伸状态,螺钉经寰枢关节部位易产生应力集中,为可能的断钉部位,临床应用时应采取有效预防措施。     

The mechanical role of laminar hook protection of pedicle screws at the caudal end vertebra

Biomechanical studies have shown hooks to be superior to pedicle screws in pull-out, especially in osteoporosis. This study evaluates the possible increase in stiffness of pedicle screws provided by laminar hooks while applying non-destructive forces to a vertebrectomy model assembled with Compact Cotrel Dubousset (CCD) instrumentation. Synthetic vertebrae were employed in a three-level vertebrectomy model. CCD screw-based three-level constructs with and without sublaminar hooks in the caudal element were tested in flexion, extension, compression, lateral bending, and torsion. There was no statistically significant advantage in adding inferior laminar hooks to a caudal end vertebra that had bilateral pedicle screws in any of the testing modes. Torsional stability, however, was augmented, but not significantly. Torsional instability and osteoporotic bone may be the clinical justifications for adding laminar hooks below screws in the caudal end vertebra.     

一种新型后路寰枢椎固定系统的设计及有限元分析

目的:基于影像学参数设计一种新型后路寰枢椎固定系统,运用有限元方法评价该系统固定的生物力学稳定性。方法:运用医学影像存档与通信系统测量工具对后弓发育正常且结构完整的成人寰椎CT进行解剖学参数测量,依据寰椎影像学测量参数设计出一种符合寰椎解剖结构的新型后路寰枢椎固定系统。对1例健康志愿者上颈椎进行薄层CT扫描,对其CT图片数字图像处理,进行网格划分、设置材料属性及载荷与边界条件,建立正常上颈椎有限元模型(正常模型),并与已发表文献对比验证其有效性;在正常模型基础上通过修改材料属性及去除横韧带构建寰枢椎失稳有限元模型(失稳模型),加载新型后路寰枢椎内固定系统至失稳模型上建立新型后路寰枢椎固定系统固定有限元模型(新型模型);运用Abaqus 2019对新型模型施加扭矩为1.5N·m,对该模型C0-C3节段屈伸、侧屈、旋转活动度进行计算分析,并与寰枢椎椎弓根螺钉固定有限元模型(椎弓根螺钉模型)对比。结果:设计出的新型后路寰枢椎固定系统符合寰椎的解剖结构,此系统由新型寰椎后弓钢板、连接棒及枢椎椎弓根螺钉组成。与以往文献对比,建立的正常模型验证有效。新型模型与正常模型相比减少了屈伸95.3%、侧屈92.6%、旋转99.0%的活动度,在各状态明显减少置入节段(C1-2)的活动度。有限元分析得出新型模型在屈伸、侧屈、旋转状态下C1-2节段活动度分别为1.10°、0.49°、0.59°,与椎弓根螺钉模型活动度相近;新型模型C2/3椎间盘最大应力在前屈、后伸、左侧屈、右侧屈、左旋转、右旋转状态下分别为3.71MPa、5.84MPa、3.09MPa、3.43MPa、2.65MPa、3.59MPa,与正常模型最大应力一致;新型后路寰枢椎固定系统固定的应力主要集中于枢椎椎弓根螺钉根部及连接棒。结论:新型后路寰枢椎固定系统固定具有良好的生物力学稳定性,可作为寰枢椎失稳内固定的补充方式。