脊柱旋转手法治疗腰椎间盘突出症的实验研究

采用模拟手法对３具新鲜尸体的脊柱标本，进行了Ｌ４．５、Ｌ５Ｓ１椎间盘后外缘应力变化的测定，和脊柱不同位置变化下腰椎小关节突相互关系改变的观察。结果发现前屈侧弯旋转法对腰椎小关节突的活动幅度最大，直立旋转法次之，向左侧旋转时小关节突作切面的旋转滑动，右侧小关节间隙增大；向右侧旋转时反之。做前屈侧弯旋转法时，当脊柱向左侧旋转时，椎间盘左后外侧压力增高，同时右后外侧压力减低；向右旋时则反之。而当旋转动作结束复原时，出现负压的一侧均出现一个微小的正压，这种正负压力多次反复的变化，可以使突出的髓核变位或变形，从而使受压的神经根减张。     

Orion钢板固定后对植骨块及小关节突应力影响的实验研究

目的：研究单纯植骨及植骨 Orion钢板内固定后对植骨块及相邻椎节小关节突应力的影响。方法：采用8具男性新鲜颈椎标本，分别行单纯植骨及植骨 Orion钢板内固定后测量植骨块及相邻椎节小关节突应力的变化。结果：单纯植骨时融合节段上小关节突的应力无明显增加，而植骨 Orion钢板内固定后则显著增加。单纯植骨及植骨 Orion钢板内固定后融合节段下小关节突的应力无明显增加。植骨 Orion钢板内固定后植骨块的应力较单纯植骨时变小。结论：植骨 Orion钢板内固定后融合节段上小关节突的应力明显增加，容易造成融合上节段的退变，并且存在一定的应力遮挡，故在治疗单纯颈椎退行性病变的患者时，使用Orion钢板内固定应持谨慎态度。     

颈椎分离损伤内固定的抗旋转和前屈强度测试

目的：比较四种颈椎内固定方法的旋转和前屈强度。方法：成年新鲜猪第２７颈椎标本５具，每具切取３个脊柱功能单位试件，切断椎间连接造成三柱分离性损伤，采用椎弓根钉、关节突钉、棘突钢丝、椎体钢板将椎骨两两固定，测试它们的旋转和前屈强度及位移大小。结果：椎弓根固定试件的旋转和前屈破坏力最大，加载过程的旋转位移大于正常，前屈位移小于正常，固定最牢。椎体钢板固定的旋转破坏力大于关节突和棘突钢丝试件，前屈破坏力小，位移大。关节突固定的旋转破坏力大于棘突钢丝，角位移小。结论：颈椎严重损伤在选用内固定后，由于抗旋转和前屈强度及位移差异，可适当辅以外固定     

腰椎手法关节和椎间盘压力的力学研究

目的通过压力测量对新鲜脊柱标本进行生物力学实验,测量不同手法对椎间盘和关节的应力变化。方法本实验采用新鲜中年男性尸体,制作脊柱及骨盆标本(保存肌肉韧带),在不同力学状态下(脊柱关节冲击手法、关节松动手法和脊柱单纯旋转),应用压力测量技术获得腰椎L_1-L_5关节突内及椎间盘压力数据。结果实验发现松动手法主要作用点为腰椎关节,对椎间盘影响小。冲击手法对于腰椎关节、椎间盘压力影响较大,在扭力中心有明显的扭力集中现象。结论关节手法对腰椎关节产生明显的压力影响,冲击手法尤甚。如何把握这种压力影响,可能是发挥手法效应和控制副损伤的关键,这为进一步解释手法风险和副作用产生的机理,提供了良好的证据。     

后部结构对腰椎前屈／后伸稳定性的影响

目的：探讨小尾寒羊L5／6后部结构分级切除对腰椎前屈／后伸稳定性的影响。方法：利用改良的定位移生物力学测试方法,对L5／L6后部结构依次分级切除：Ⅰ正常→Ⅱ全椎板减压→Ⅲ左侧关节突切除1／2→Ⅳ左侧关节突全部切除→Ⅴ右侧关节突切除1／2→Ⅵ右侧关节突全部切除,Instron8874试验机依次测试标本前屈／后伸椎间运动的变化。结果：全椎板减压和左侧关节突的全部切除对于前屈／后伸的稳定性影响不大（P〉0．05）;当再切除右侧关节突1／2时,稳定性影响明显（P〈0.05）。结论：在保证手术视野的情况下,腰椎后路手术力求做到微创,尽量保留后部结构的完整性。     

颈椎人工椎间盘置换或前路融合内固定术后关节突间压力的改变

目的:通过测量颈椎前路融合内固定或人工椎间盘置换术后关节突间压力的变化,探讨两种手术对颈椎手术节段后部结构的力学影响。方法:6具成年男性新鲜尸体颈椎标本(C2～C7)作为测试对象,分为完整颈椎组、人工椎间盘置换组及前路融合内固定组。在完整颈椎测试后,所有标本先后行C4/5节段Prestige-LP人工椎间盘置换和前路C4/5节段植骨融合固定术后进行测试。将预制的压敏片置于C4/5左侧关节突关节内,标本先给予75N跟随载荷,再持续加载纯力偶进行三维运动测试。屈伸和侧屈最大运动载荷为2.0N·m、旋转最大运动载荷为4.0N·m,测量加载后的运动范围和零运动载荷、最大运动载荷时的关节突间压力。结果:与零运动载荷时相比,在运动加载后完整颈椎组和颈椎人工椎间盘置换组在后伸、左侧屈和右旋时均表现出左侧关节突间压力明显增大(P0.05);但前屈、右侧屈和左旋时左侧关节突间压力变化没有差异;颈椎前路融合内固定组各运动加载后关节突间压力与零运动载荷下压力均无显著性差异(P0.05)。在三个测试组间比较,完整颈椎组和人工椎间盘置换组在各运动载荷下的关节突间压力最为接近;颈椎前路融合内固定组虽然在后伸、左侧屈和右旋时关节突间压力都有减小,但与其他两组比较无显著性差异(P0.05)。结论:颈椎人工椎间盘成形术后关节突间压力与正常颈椎相比没有明显改变,可以有效地维持关节突间正常生理压力。     

腰椎间盘切除与人工椎间盘置换前后上位关节突关节内压力改变

目的测量腰椎间盘完整时、切除后及人工椎间盘置换后上一关节突关节内压力变化,探讨椎间盘切除及人工椎间盘置换对上一节段的影响,为人工椎间盘的临床应用提供理论依据。方法在7具成人新鲜尸体标本上,分别以200～2000N的轴向、1～10Nm的后伸、侧弯加载,测量L4、5椎间盘完整时、切除后及人工椎间盘置换后L3、4关节突关节内的压力并进行统计学分析。结果相同载荷(轴向、后伸、侧弯)下,上一关节突关节内平均压力:椎间盘切除后与椎间盘完整时差异有统计学意义(P<0.01);人工椎间盘置换后与椎间盘完整时无统计学意义(P>0.05);人工椎间盘置换后与椎间盘切除后差异有统计学意义(P<0.01)。结论腰椎间盘切除后上一关节突关节内压力降低,单纯椎间盘切除可影响腰椎的力学分布,进一步导致继发性腰椎结构的退行性改变;人工椎间盘置换后上一关节突关节内压力与正常一致,对腰椎结构具有保护作用,并提供了一定的生物力学基础和理论依据。     

颈椎前路手术后邻近节段运动变化的生物力学研究

目的利用压敏片(PSF)技术,测量颈椎前路手术后关节突关节内压力的变化,探讨颈前路手术后远期邻近节段退变的生物力学发病机制。方法10具新鲜成人颈椎尸体标本(C2～T1),行前路C4,5椎间盘切除、C4,5椎间植骨钢板内固定术。将压敏片置于关节突关节内,在脊柱三维运动试验机上测量0载荷和2N·m载荷下,后伸、左右侧弯、左右旋转过程中关节突关节内压力的变化。结果颈椎前路手术后,邻近节段关节突关节内的压力增加,以后伸和左右旋转时最为明显,差异有显著性意义(P<0.05)。结论颈椎前路短节段植骨融合术后,邻近节段关节突关节内压力明显增加,可诱发邻近节段关节突关节的退变,从而引起相应的病症。     

弯腰挺立手法治疗腰骶关节紊乱的有限元分析

目的:分析腰骶关节紊乱患者有限元模型及施加弯腰挺立手法后的位移、应力及作用机制。方法 :建立1例腰骶关节紊乱患者的三维有限模型,运用有限元分析方法对模型进行轴向、34°斜向上、垂直向上3种工况加载进行观察分析。结果:腰骶关节紊乱模型应力分布,L_5椎体集中在下终板中央、椎间盘集中在间盘中央,S_1及相关结构应力集中分布在椎体前后缘。模拟手法后应力主要集中在L_5椎体上终板前缘、后缘和下终板中央圆形区域,椎体后部相关结构集中在椎弓根腹侧、峡部和椎板背侧,椎间盘应力分散于椎体后缘;S_1椎体相关结构集中在骶骨椎体后缘和骶骨嵴上。位移结果:腰骶关节紊乱模型中左侧横突、上下关节突和棘突左侧部分向左明显移位,椎间盘向前突出移位。模拟手法后:L_5椎体下切迹向前上方移位,椎间孔面积增大,L_5椎体下关节突向前移行,骶骨上关节突向前下方移位,关节突关节距离加大,骶骨位移最大集中在椎体后缘和骶正中嵴上。结论:腰骶关节建模成功可进行有限元分析;弯腰挺立手法作用机制明确,用于治疗腰骶关节紊乱有效、安全可施。     

Orion钢板固定后对植骨块及小关节突应力影响的实验研究

目的:研究单纯植骨及植骨 Orion钢板内固定后对植骨块及相邻椎节小关节突应力的影响.方法:采用8具男性新鲜颈椎标本,分别行单纯植骨及植骨 Orion钢板内固定后测量植骨块及相邻椎节小关节突应力的变化.结果:单纯植骨时融合节段上小关节突的应力无明显增加,而植骨 Orion钢板内固定后则显著增加.单纯植骨及植骨 Orion钢板内固定后融合节段下小关节突的应力无明显增加.植骨 Orion钢板内固定后植骨块的应力较单纯植骨时变小.结论:植骨 Orion钢板内固定后融合节段上小关节突的应力明显增加,容易造成融合上节段的退变,并且存在一定的应力遮挡,故在治疗单纯颈椎退行性病变的患者时,使用Orion钢板内固定应持谨慎态度.     

手法治疗脊柱滑脱症的临床与实验研究

应用位移传感器测量新鲜尸体标本模拟运动及旋转复位时位移情况，可见腰椎下关节突产生向上及侧方位移，使椎间孔扩大，椎体产生相应向后回位趋势；肉眼观察峡部裂脊柱标本在手法作用下出现峡部裂间距加大。对３５例腰椎滑脱症病人手法治疗，效果较为满意，尤对退变型滑脱为佳；仰卧屈膝，屈髋腰起坐锻炼和等张肌力锻炼是治疗该病的重要措施。     

Strain of the facet joint capsule during rotation and translation range-of-motion tests: an in vitro porcine model as a human surrogate

BACKGROUND CONTEXTPrior data about the modulating effects of lumbar spine posture on facet capsule strains are limited to small joint deviations. Knowledge of facet capsule strain during rotational and translational intervertebral joint motion (ie, large joint deviations) under physiological loading could be useful as it may help explain why visually normal lumbar spinal joints become painful.PURPOSEThis study quantified the strain tensor of the facet capsule during rotation and translation range-of-motion tests.STUDY DESIGN/SETTINGStrain was calculated in isolated porcine functional spinal units. Following a preload, each specimen underwent a flexion/extension rotation (F/E) followed by an anterior/posterior translation (A/P) range-of-motion test while under a 300 N compression load.METHODSTwenty porcine spinal units (10 C3–C4, 10 C5–C6) were tested. Joint flexion/extension was imposed by applying a ±8 Nm moment at a rate of 0.5°/s, and translation was facilitated by loading the caudal vertebra with a ±400 N shear force at a rate of 0.2 mm/s. Points were drawn on the exposed capsule surface and their coordinates were optically tracked throughout each test. Strain was calculated as the displacement of the point configuration with respect to the configuration in a neutral joint position.RESULTSCompared to a neutral posture, superior-inferior strain increased and decreased systematically during flexion and extension, respectively. Posterior displacement of the caudal vertebra by more than 1.3 mm was associated with negative strains, which was significantly lower than the +4.6% strain observed during anterior displacement (p≥.199). The shear strain associated with anterior translation was, on average, −1.1% compared to a neutral joint posture.CONCLUSIONSThese results demonstrate that there is a combination of strain types within the facet capsule when spinal units are rotated and translated. The strains documented in this study did not reach the thresholds associated with nociception.CLINICAL RELEVANCEThe magnitude of flexion-extension rotation and anterior-translation may glean insight into the facet capsule deformation response under low compression (300 N) loading scenarios. Further, intervertebral joint motion alone, even under low compression loading, does not appear to initiate a clinically relevant pain response in the lumbar facet capsule of a nondegenerated spinal joint.     

Biomechanics of sequential posterior lumbar surgical alterations.

Compromise of the functional integrity of the posterior lumbar ligaments and facet joints is a common occurrence after repeated lumbar operative procedures. To evaluate the biomechanical effects of sequential surgical alterations, this investigation analyzed bilateral facetectomies (medial, total, and total with posterior ligament section) in three segments of human cadaveric lumbar spines under increasing compression-flexion. These iatrogenic alterations, designed to replicate common methods of surgical exposure, were created at the lower intervertebral joint (L4-5) while the upper joint (L3-4) remained intact. Overall strength characteristics in the physiological range of 400 N and 600 N demonstrated significant differences (p less than 0.05) in applied compressions for all preparations compared to the intact specimen. Comparison of sequential surgeries, however, did not demonstrate this tendency. Significant changes in the movement of the spinous processes at the upper (unaltered) level occurred only after posterior ligament section, whereas the lower (altered) level showed markedly increasing distraction of both the facets and the spinous processes with sequential operations. Sectioning of the supraspinous/interspinous ligament and associated fascial attachments resulted in a marked transfer of motion to the altered level. This was manifested by the increased anterior displacement of the centrode at the lower level associated with probable posterior migration of the centrode at the upper level. These data suggest that the effects of progressive surgical alterations of the lumbar facet joints are controllable in a preparation undergoing acute compression-flexion loads until the supraspinous/interspinous ligaments, with associated residual tendinous, midline muscle, and fascial attachments, are violated.     

Influence prediction of injury and vibration on adjacent components of spine using finite element methods

OBJECTIVES: A three-dimensional finite element (FE) model of the lumbar spine L3-L5 segment, the ligaments of which were assumed to be nonlinear materials, was established based on the actual vertebra geometry to investigate the influence of the injury lumbar spine on its adjacent components on the condition of whole-body vibration. Several injury conditions of the spine components were assumed, such as facetectomy, nucleotomy, and removal of bony posterior elements. METHODS: The dynamic FE analyses were carried out for those FE conditions under cyclic compression loads at the frequencies of 5 and 10 Hz. Then a comparison between the dynamic results and the static results was conducted to analyze the influence of both the nucleus injury and the facet joint injury on the adjacent intervertebral discs. RESULTS AND CONCLUSIONS: The results indicate that the lumbar spine exhibits not only vertical vibration but also the flexion--extension motion during vibration. The denucleation will cause high stress and large disc bulge on the disc annulus under vibration. The facet joints of lumbar spine can limit the motion amplitude of flexion-extension and protect both the posterior regions and the posterolateral regions of disc annulus from large strain and stress during vibration. The facet joint removal will increase the stress of disc annulus by around 15% at the posterior region for the conditions of nucleotomy or no vibration. The stress of annulus circumference is higher at the posterolateral region than that of other regions of annulus circumference, and the facet joint removal may exacerbate the intervertebral disc degeneration on the condition of whole-body vibration.     

Emerging directions in motion preservation spinal surgery

In this review, we focus on novel surgical techniques and spinal arthroplasty systems inactive development. First, we discuss systems that allow for minimally invasive approaches to the lumbar disc space: (1) lateral approaches, (2) posterior approaches,and (3) oblique approaches. These techniques offer the potential for a minimally invasive lumbar arthroplasty system. Second, we discuss novel facet replacement technology. The facet joints, with the intervertebral disc, comprise the three-joint complex of the spinal unit. Facet joint health is thus crucial to proper disc biomechanics and function. Finally,we discuss dynamic neutralization of the lumbar spine with an artificial posterior tension band device. This allows for a certain degree of immobilization without fusion. Minimally invasive surgical approaches, facet arthroplasty, and posterior tension band devices may be the future of motion preservation spinal surgery.     

椎体位移与椎间盘内压力变化的实验研究

目的 探讨椎体位移对椎间盘内压力的影响,纠正椎体位移在手法治疗椎间盘突出症中的意义。方法 选择8只杂种犬,取L3－L5段脊柱椎体,固定在自制的器械上,将L4椎体后仰前倾,测量新鲜杂种狗腰椎椎体位移及纠正后椎间盘内压力变化。结果 当椎体后仰椎间盘后外侧压力增加明显（P＜0.01）,椎体前倾时椎间盘后外侧压力减小明显（P＜0.01）,而当椎体恢复原位,压力恢复原水平,两者无显著差异（P＞0.05）。结论 1.椎体位移使相邻椎间盘局部应力发生变化。椎体后仰时下方椎间盘后外侧力明显增大。2.手法治疗通过纠正椎体位移,可以确切、有效的使来自椎间盘内部的异常压力消失,解除对神经根的压迫从而达到治愈的目的。     

后部结构分级切除对下腰椎稳定性影响的实验研究

目的 探讨小尾寒羊L5,6后部结构分级切除对腰椎稳定性的影响.方法 选取14只小尾寒羊,截取L4～L7脊柱标本.实验前摄正、侧位X线片以排除脊柱疾患,CT定位关节突关节分级切除.对L5,6节段后部结构依次分级切除如下:Ⅰ正常→Ⅱ全椎板减压→Ⅲ左侧关节突切除1/2→Ⅳ左侧关节突全部切除→Ⅴ右侧关节突切除1/2→Ⅵ右侧关节突全部切除→结束.利用Instron 8874液压伺服动态生物力学测试系统依次测试标本六个自由度上椎间运动的变化,计算平均刚度.利用SPSS 11.5行单因素方差分析,检验水准α值取0.05.结果 全椎板减压和左侧关节突的全部切除对于前屈或后伸的稳定性影响不大;当再切除右侧关节突1/2时,前屈或后伸的平均刚度比正常时分别下降32.33%和30.83%.腰椎后路结构的切除对于腰椎侧弯的稳定性影响不大.全椎板减压即出现左和右扭转失稳,平均刚度分别比正常时下降26.13%和26.20%,关节突关节与扭转的稳定性亦具有重要意义,特别是对对侧扭转的稳定性.结论 行腰椎后路手术时,在保证手术视野的情况下,力求做到微创,尽量保留后部结构的完整性.     

An immunohistochemical study of the dorsal capsule of the lumbar and thoracic facet joints

STUDY DESIGN: The molecular composition of the extracellular matrix in the dorsal capsules of lumbar and thoracic facet joints was analyzed immunohistochemically. OBJECTIVES: To determine whether the immunohistochemical profile of the lumbar joint capsule suggests a role of the capsule in limiting axial rotation of the lumbar motion segment. SUMMARY OF BACKGROUND DATA: During axial rotation of the lumbar vertebrae, the axis of rotation shifts toward the facet joints in the direction of rotation. Thus, the capsule of the opposing joint should become tensed and wrap around the inferior articular process. Previous studies suggest that wrap-around ligaments are fibrocartilaginous. However, thoracic joint capsules are largely shielded from such loading and should be purely fibrous. METHODS: Dorsal capsules were removed from lumbar and thoracic facet joints of six adult cadavers. Specimens were immunolabeled with monoclonal antibodies for collagens, chondroitin, dermatan and keratan sulfates, versican, tenascin, aggrecan and link protein. Antibody binding was detected using the Vectastain ABC 'Elite' peroxidase kit (Vector Laboratories, Inc., Burlingame, CA). RESULTS: Both lumbar and thoracic joint capsules immunolabelled for most glycosaminoglycans and for Type I, III and VI collagens. However, labeling for Type II collagen, chondroitin-6-sulfate, aggrecan, and link protein was restricted to lumbar capsules. Such labeling was constantly seen at entheses and occasionally in the midsubstance. CONCLUSIONS: The molecular composition of the lumbar joint capsule suggests that it acts as a fibrocartilaginous, 'wrap-around' ligament that withstands compression in addition to tension during torsional movements of the lumbar spine. It wraps around the inferior articular process as rotation occurs and limits further movement.     

Effectiveness of posterior tension band fixation in the thoracolumbar seat-belt type injuries of the young population

The effects of different parameters on the mechanical behaviour of the lumbar spine were in most cases determined deterministically with only one uncertain parameter varied at a time while the others were kept fixed. Thus most parameter combinations were disregarded. The aim of the study was to determine in a probabilistic finite element study how intervertebral rotation, intradiscal pressure, and contact force in the facet joints are affected by the input parameters implant position, implant ball radius, presence of scar tissue, and gap size in the facet joints. An osseoligamentous finite element model of the lumbar spine ranging from L3 vertebra to L5/S1 intervertebral disc was used. An artificial disc with a fixed center of rotation was inserted at level L4/L5. The model was loaded with pure moments of 7.5 Nm to simulate flexion, extension, lateral bending, and axial torsion. In a probabilistic study the implant position in anterior–posterior (ap) and in lateral direction, the radius of the implant ball, and the gap size of the facet joint were varied. After implanting an artificial disc, scar tissue may develop, replacing the anterior longitudinal ligament. Thus presence and absence of scar tissue were also simulated. For each loading case studied, intervertebral rotations, intradiscal pressures and contact forces in the facet joints were calculated for 1,000 randomized input parameter combinations in order to determine the probable range of these output parameters. Intervertebral rotation at implant level varies strongly for different combinations of the input parameters. It is mainly affected by gap size, ap-position and implant ball radius for flexion, by scar tissue and implant ball radius for extension and lateral bending, and by gap size and implant ball radius for axial torsion. For extension, intervertebral rotation at implant level varied between 1.4° and 7.5°. Intradiscal pressure in the adjacent discs is only slightly affected by all input parameters. Contact forces in the facet joints at implant level vary strongly for the different combinations of the input parameters. For flexion, forces are 0 in 63% of the cases, but for small gap sizes and large implant ball radii they reach values of up to 533 N. Similar results are found for extension with a maximum predicted force of 560 N. Here the forces are mainly influenced by gap size, implant ball radius and scar tissue. The forces vary between 0 and 300 N for lateral bending and between 0 and 200 N for axial torsion. The parameters that have the greatest effect in both loading cases are the same as those for extension. Intervertebral rotation and contact force in the facet joints depend strongly on the input parameters studied. The probabilistic study shows a large variation of the results and likelihood of certain values. Clinical studies will be required to show whether or not there is a strong correlation of parameter combinations that cause high facet joint forces and low back pain after total disc replacement.     

退行性腰椎侧凸生物力学的研究进展

退行性腰椎侧凸（DLS）的发生、发展与腰椎生物力学性能的改变关系密切。椎间盘、小关节以及腰椎肌肉群不同程度的退变均可能引起腰椎节段受力不平衡,形成腰椎侧凸,进而进一步增加腰椎承受的负重,并改变其受力方向,二者形成恶性循环,加重病情。该文就腰椎整体、椎间盘、小关节以及腰椎肌肉群的生物力学性能改变及其与DLS之间的关系加以综述,为DLS的临床治疗提供理论基础。