单侧小关节分级切除对腰椎稳定性影响的三维运动研究

采用８具新鲜尸体腰椎功能单位，通过脊柱三维运动实验机施加最大载荷为１０．０Ｎｍ的６种力偶，使脊柱产生前屈／后伸、左／右侧弯和左／右轴向旋转运动。经立体摄像计算机图像处理得到Ｌ_２～Ｌ_３节段的运动范围（ＲＯＭ）、中性区（ＮＺ）和弹性区（ＥＺ）等参数。将完整标本测量的结果为自身对照组，然后在Ｌ_２、Ｌ_３节段依次切除左侧小关节１／３、１／２、和３／３。作ｔ检验和方差分析来分析单侧小关节切除对腰椎三维运动的影响。结果表明：单侧小关节切除１／３后ＲＯＭ增加不显著（Ｐ＞０．０５），不影响脊柱的稳定；小关节全切除后后伸、左侧弯和右旋的ＲＯＭ增加显著（Ｐ＜０．０５）。小关节切除１／２后ＲＯＭ虽增加不显著，但经方差分析与小关节全切的结果无明显差异，说明小关节切除范围超过１／２将导致脊柱失稳。     

单节段腰椎后部结构逐级切除对脊柱三维运动稳定性的影响

目的 观察单节段脊柱后部结构对腰椎三维运动稳定性的影响。方法 选用6具成人新鲜尸体脊柱标本腰1-骶1(L1～S1)，采用单节段逐步切除腰椎后部结构的方法，形成7种状态，通过脊柱三维运动试验机施加10N．m的载荷，使脊柱产生前屈／后仲，左／右侧屈和左／右轴向旋转运动。结果 切除脊柱的后部结构后，在脊柱的三维稳定性中，前屈及轴向旋转运动的稳定性最易受到破坏，前屈平均运动范围增加5．1度，旋转增加3．4度。结论 除小关节骨性结构及关节囊外，后部结构对维持腰椎的稳定性具有重要作用，特别是对前屈及轴向旋转运动。     

利用成年猪脊柱制作胸腰段后凸畸形模型进行脊柱三维运动实验

[目的]探讨应用成年猪脊柱制作胸腰段后凸畸形模型进行生物力学实验研究的可行性,以及胸腰段后凸畸形对腰椎三维运动的生物力学影响.[方法]收集24例成年家猪胸腰椎脊柱新鲜标本,随机分为三组,制造两个Cobb角度水平的胸腰段后凸畸形和相应的腰椎过度前凸模型,进行脊柱三维运动实验,测量L2、3和L4、5的前屈/后伸、左/右侧弯、左/右旋转的运动范围( ROM)以及所对应的中性区(NZ)的大小,对各组数值进行方差分析,用snk(q检验)法对分组变量进行多重比较.[结果]后凸的胸腰段对邻近运动节段(L2、3)矢状面上的运动(前屈/后伸)ROM以及NZ的影响更明显,P＜0.05,而左/右侧弯、左/右旋转的ROM及NZ没有统计学差异,P＞0.05;而下腰椎运动节段(L4、5)的前屈/后伸、左/右侧弯、左/右旋转的ROM及NZ均没有统计学差异,P＞0.05.[结论]利用成年猪脊柱制作胸腰段后凸畸形模型进行脊柱三维运动实验是可行、简便、有效的;腰椎前屈/后伸运动范围的过度增大,是胸腰段后凸畸形后为维持脊柱矢状面平衡的一个重要代偿改变,且ROM的增大以上腰椎的改变更为明显.     

单侧小关节分级切除对腰椎稳定性影响的三维有限元分析

目的研究单侧小关节分级切除对腰椎稳定性的影响。方法采用三维有限元法建立腰椎活动节段（L4～5）的数学力学模型。结果a）在前屈和后伸状态下,各实验切除组与正常对照组无显著性差异（P〉0．05）;b）在左／右侧弯和左／右轴向旋转状态下,小关节切除1／2以上的各组均与正常组有显著性差异（P〈0．05或P〈0．01）。结论a）单侧小关节分级切除对腰椎节段的前屈、后伸稳定性无显著性影响;b）当腰椎小关节切除范围超过1／2,对腰椎节段侧弯运动有显著性影响,尤其以向对侧侧屈为甚;c）当一侧小关节切除超过1／2后,由于失去了小关节和关节囊的限制,导致腰椎活动节段轴向旋转范围增加显著。     

短节段DRFS脊柱内固定术后即刻刚度的变化及其意义

目的测试短节段猪脊柱标本在完整、失稳后及内固定后的刚度变化。方法选择12节段猪脊柱标本12具,测定其前屈、后伸、侧屈及旋转时的刚度;切除椎间盘、小关节及前后纵韧带松解脊柱,测定其各项运动刚度;用DRFS脊柱内固定系统进行短节段内固定后重复测试各项运动刚度。结果与完整脊柱的刚度（前屈、后伸、侧屈及旋转的刚度分别为0.389±0.305,1.090±0.355,1.012±0.301,1.232±0.441,1.103±0.414,1.013±0.402）相比,失稳后脊柱各项运动的刚度（前屈、后伸、侧屈及旋转的刚度分别为0.216±0.218,0.278±0.204,0.255±0.124,0.409±0.169,0.633±0.218,0.626±0.216）均明显减少（P〈0.05）,而内固定后脊柱各项运动的刚度（前屈、后伸、侧屈及旋转的刚度分别为（0.568±0.351,0.679±0.151,0.759±0.314,0.729±0.311,1.006±0.304,0.975±0.218）均明显高于失稳后脊柱,与完整脊柱前屈、侧屈及旋转运动无明显差异,后伸运动的刚度明显高于完整脊柱（P〈0.01）。结论短节段脊柱内固定后各项运动的刚度明显高于脊柱失稳后,与完整标本相比除后伸运动的刚度明显增高外,其余各方向的运动刚度相近。     

双侧小关节分级切除对腰椎稳定性影响的三维运动研究

采用８具新鲜尸体腰椎功能单位，通过脊椎三维运动实验机施加最大载荷为１０．０Ｎ．ｍ的６种力偶，使脊柱产生前屈，后伸，左右侧弯和左，右轴向旋转运动。经立体摄像计算机图像处理得到Ｌ１－２节段的运动范围（ＲＯＭ），中性区（ＮＺ）和弹性区（ＥＺ）等参数。首先对完整标本进行测量，测得的结果为自身对照组，然后在Ｌ１－２节段依次切除双侧小关节１／３，１／２和３／３，根据节段间的运动变化，定量地分析小关节切除对腰椎     

胸腰段脊柱爆裂型骨折机理及实验模型

目的：建立Ｌ１单椎体爆裂型骨折模型，探讨胸腰段脊柱爆裂型骨折机理及损伤后三维运动的变化情况。方法：收集７例新鲜成人Ｔ８～Ｌ５节段胸腰椎标本，在脊柱三维运动试验机上测试正常标本Ｔ１２～Ｌ１及Ｌ１～Ｌ２节段的三维运动范围。然后施以５００Ｊ的能量撞击，撞击后拍摄Ｘ线正侧位片，并重复测试损伤后标本的三维运动范围。结果：７例标本的Ｌ１均产生爆裂型骨折。在Ｔ１２～Ｌ１节段和Ｌ１～Ｌ２节段标本在前屈、后伸、左右侧弯和左右轴向旋转方向的运动范围和中性区均有显著性增大（Ｐ＜０．０１）。结论：我们所建立的单椎体爆裂型骨折模型为脊柱的实验研究提供了一个较为理想的方法。在胸腰椎爆裂型骨折中，脊柱在各个方向上的运动范围均有显著的急性不稳定性     

颈椎前、后路手术的运动学变化

目的：为评价几种颈椎前、后路手术对颈椎稳定性的影响。方法：取四具意外伤亡的新鲜尸体Ｃ２～Ｔ１标本，保留所有韧带和椎间连接，行如下手术：１．Ｃ５，６椎间盘切除；２．椎间植骨；３．前方椎体钢板螺钉内固定；４．Ｃ５全椎板减压；５．Ｃ５，６椎弓根钢板螺钉内固定（去除该部椎体钢板）；６．去除椎弓根钢板和植骨块。测量上述诸术Ｃ２～Ｔ１各节段间的前屈、后伸、左右侧弯，左右旋转运动变化，以完整标本作对照。结果：Ｃ５，６椎间盘切除后的前屈运动增加６７．８％（Ｐ＜０．０１），后伸运动增加５９％（Ｐ＜０．０１），侧弯和旋转运动增加１０％（Ｐ＞０．０５）。植骨后运动变化不明显（Ｐ＞０．０５）。椎体钢板和椎弓根内固定后各向运动均明显减少（Ｐ＜０．０１），以侧弯和旋转尤为明显，椎弓根固定后明显增强三维稳定性。而椎体钢板固定的旋转稳定性最佳。然椎间盘和椎板同时切除引起三维运动明显不稳。损伤和固定节段的运动增大和减小，伴随其相邻上或下节段运动的代偿性减小和增大，但无显著性。结论：以上结果为临床开展颈椎前、后路手术所造成的稳定性变化和在手术内外固定方法的选择上提供了运动学和生物力学理论参考     

5种后路脊柱内固定器械的生物力学评价

采用７具新鲜尸体胸腰段脊柱标本（Ｔ８～Ｌ５），损伤Ｔ１２～Ｌ１的后部结构造成脊柱失稳。在失稳的脊柱标本上轮流安装５种常用后路内固定器械，分别进行脊柱稳定性测试，得出５种内固定器械对损伤节段的固定效果。结果表明，５种内固定器械对失稳脊柱节段的屈／伸及右／左侧弯运动均有良好的固定作用，但对轴向旋转运动均不能控制到完整脊柱的稳定水平。相对而言，Ｄｉｃｋ钉的作用较优。     

脊柱胸腰段应力分布与骨折相关性的三维有限元分析

【摘要】 目的：观察脊柱胸腰段骨折与椎体骨性结构及韧带间应力分布的相关性,探索脊柱胸腰段椎体骨折的力学机制。方法：招募8名健康男性青年志愿者,行脊柱全长X线片和CT检查排除脊柱畸形、肿瘤及骨病,对脊柱各椎体及股骨行骨密度测定排除骨质疏松。均行自T11椎体上终板至L2椎体下缘CT薄层扫描,将8名志愿者CT图像参数导入ABAQUS 2016软件中进行标准化,并进行有限元网格化构建。应用MIMICS 17.0、GEOMAGICS 15.0和PRO/ENGINEER 5.0软件处理,建立脊柱胸腰段有限元模型,测量模型相关参数,并验证模型有效性。在T11椎体上终板上加载竖直轴向载荷500N、附加扭矩10N·m模拟垂直压缩、前屈、后伸、左右侧屈、左右旋转7种运动状态,使用ABAQUS软件对有限元模型7种运动状态下的应力分布特点及变化规律进行分析,观察应力分布与脊柱胸腰段骨折的相关性。结果：建立的三维有限元模型共有309583个节点和428760个单元,包括4个椎体、3个椎间盘、前纵韧带、后纵韧带、横突间韧带、棘间韧带等结构。7种运动状态下的数据与文献报道的数据无明显偏差,模型有效。T11~L2椎体椎弓根截面积分别为135mm2、154mm2、105mm2、139.2mm2。应力云图结果显示各运动状态下高应力区存在于椎体的松质骨、椎弓根及其周围骨皮质。在垂直压缩状况下,T12椎体所受应力最大（617.4MPa）,前屈状态下T11所受应力最大（200.7MPa）,后伸、左右侧屈和左右旋转状态下L1椎体所受应力最大（314.2MPa、574.4MPa、626.2MPa、641.3MPa、527.1MPa）,且前屈体位时椎体所能承受的应力最小,左旋转时所能承受的应力最大。垂直压缩状况下T12椎体发生骨折, 前屈状态下T11发生骨折伴韧带损伤,后伸、左右侧屈和左右旋转状态下L1椎体发生骨折伴韧带损伤。骨折发生时,前纵韧带在后伸、左右侧屈状态下存在高应力区,后纵韧带在前屈状态下存在高应力区,横突间韧带和棘间韧带在前屈、左右侧屈、左右旋转状态下存在高应力区。结论：在构建包括重要韧带、椎间盘等软组织结构的脊柱胸腰段三维模型中,椎体松质骨、椎弓根及其周围骨皮质、韧带均存在高应力区,不同状态下所受应力最大椎体不同,发生骨折的椎体和韧带损伤也不同;L1椎弓根截面积最小,最易发生骨折。     

全脊椎截骨术使脊髓缩短对脊髓功能影响的临床观察

对32例各种类型的脊柱后凸和后侧凸患者行全脊椎截骨加器械矫正术，截骨后使脊髓缩短2～5cm，平均2．8cm。临床结果表明，脊髓缩短在4cm以内者脊髓功能正常，双下肢无神经症状出现，而超过4cm者，由于脊髓迂曲变宽太多，骨性椎管容纳不了就会挤压脊髓产生双下肢神经症状。2例脊髓牵长1cm者双下肢立即出现神经症状。说明脊髓对缩短有很大程度的耐受力，而对牵长则极不耐受。     

Classification of spinal injuries based on the essential traumatic spinal mechanisms

STUDY DESIGN: A biomechanical unitary classification of spinal injuries is proposed. OBJECTIVE: To present an evaluation of spinal injuries based on the essential traumatic spinal mechanisms: axial deformation, torsion, translation and combined mechanisms in connection with the concept of the stabilizing axial spinal pillar. SETTING: Hospital 'Sf. Treime', Iasi, Romania. METHODS: The essential mechanisms of spinal injuries are considered: (1) axial deformation with (a) compression (centric or eccentric), most often eccentric, including compression in flexion or extension; (b) spinal elongation with distraction as centric elongation, but frequently axial eccentric elongation and a flexion or extension injury; (2) torsion or axial spinal rotation, (3) segmental translation, with a shearing version for the double translation and (4) combined mechanisms - the most frequent situation. Over 300 patients with spinal injuries were analysed and the spinal instability was determined using the criteria of clinical instability. The cases of spinal instability were studied in connection with the types of lesion of the central axial spinal pillar. RESULTS: All cases with lesions of the central axial spinal pillar had traumatic spinal instability. The spinal instability was absent in cases of isolated lesions of the anterior or posterior secondary pillar. The X-ray and spinal CT analysis of the traumatic spinal lesions showed the types of lesions and specified the mechanisms of spinal injuries. The combined mechanisms were responsible for the majority of the spinal injuries. CONCLUSIONS: Spinal instability occurs because of the lesion of the central axial spinal pillar The types of lesions of the central spinal pillar and of the secondary spinal pillars are determined by the essential traumatic spinal mechanisms: axial deformation (with compression or elongation), axial rotation, translation and most frequently the above combined mechanisms.     

Effects of spinal analgesics on spinal circulation: the safety standpoint

Administration of spinal analgesics around the spinal cord requires safety assessment due to the possibility of inflicting neurotoxic damage. Thus, neurotoxicologic evaluation should be performed for effective, safer spinal antinociception. Every potential agent for spinal administration should be studied in animals for its effects on spinal blood flow or vessels before any attempt is made to administer the drug to humans. As the spinal cord normally has a marginal blood flow, excessive vasoconstriction might produce spinal cord ischemia and consequent neurologic dysfunction. This review therefore focuses on the effects on the spinal circulation induced by well-known spinal analgesics employed in the treatment of acute and chronic pain disorders.     

脊柱骨母细胞瘤的临床研究进展

脊柱是骨母细胞瘤最常见的发病部位,主要侵及脊柱的附件结构,单发椎体少见。在组织学上该肿瘤并无恶性表现,但临床上常表现出很明显的侵袭性,甚至有恶变的可能。大多数患者存在疼痛症状,肿瘤侵犯压迫脊髓时会产生不同程度的神经损害。手术治疗是脊柱骨母细胞瘤最重要的治疗措施,肿瘤一经发现均应尽快手术切除,手术术式的选择应根据Enneking system分期,切除不彻底容易复发。目前放化疗在脊柱骨母细胞瘤的应用还存在争议,不建议作为骨母细胞瘤的常规治疗手段。     

Experimental determination of the effect of progressive sharp-angle spinal deformity on the spinal cord

Neurological deficit is a serious though not well-known complication associated with spinal deformity. Sharp-angle kyphosis may be congenital, traumatic, degenerative, infectious, or iatrogenic in origin. Many kyphotic deformities are underestimated, thus leading to severe neurological deficit. In order to determine exactly what procedures of angulation the patients should undergo to stabilize the spine, which are major operations, the authors analyzed in an experimental model the effects of progressive sharp angulation on the anatomy of spinal canal and cord. We found that sharp anterior angulation of 50° causes ante rior-posterior stenosis and the dura will touch the spinal cord. At 90° of angulation, the spinal cord will be squeezed and the pressure in the canal will be double what it was initially, probably leading to ischemia. The experimental confirmation (determination) of these angulations allows the physician in charge to define early in the treatment program when a surgical stabilization procedure should be included, before the angulation causes any neurological damage.     

脊柱转移瘤患者脊柱不稳评估方法的研究进展

2018年全球有1810万人被诊断为恶性肿瘤[最终约50％转移到骨骼,脊柱骨转移在骨转移中最常见(约占70％)[2],其中94％～98％的脊柱转移瘤为硬膜外转移瘤[3].恶性肿瘤脊柱转移大部分是溶骨型或混合型,其破坏了正常的骨组织结构,导致脊柱不稳,进而引起脊柱的病理性骨折、脊髓压迫等严重并发症,从而降低生存率[4]....     

Experimental study on spinal cord monitoring--changes in spinal cord evoked potentials during vertical direction distraction of the spinal cord

Experiments were carried out on 18 adult dogs ranging from 9.0 to 11.5 kg. The dogs were intubated and anesthetized with Halothene oxygen, and then mounted on a stereotaxic spinal apparatus. Facetectomies and a discectomy between L1 and L2 vertebrae were performed readily to give traction force to the spinal cord. Spinal cord function was monitored by the first and second negative deflections (I and II, respectively) of the descending spinal cord evoked potentials (descending SCEP) elicited at T7 and recorded at L4 through bipolar catheter electrodes. Both of them were inserted at the midline of the dorsal epidural space. The study was conducted in two parts. In the first part, the cyclic distraction-release program was carried out until motor function was impaired. Distraction was increased in increments of 5 mm, each time maintained for 10 minutes and then totally released for 10 minutes. If neurological deficits in the hind limbs were confirmed by the wake-up test, which was performed every 10 minutes after distraction and release, the 10 minutes' release period was extended for a total period of 30 minutes. The first change in the experimental protocol was transient augmentation of the amplitude of the II deflection which was always observed on a slight distraction, while the I deflection did not change in its amplitude and latency. Each distraction produced a reversible slight reduction of the amplitudes with delay of latencies of the I and II deflections before motor disturbance occurred. However, at a certain traction level paraparesis accompanied by irreversible decrease of amplitudes and delay of latencies was observed, which was confirmed by the wake-up test. At this point, which was designated as the critical point, SCEPs were so time dependent that only a slight amplitude reduction was noted immediately after distraction, but it decreased quickly in a short time during this traction level. Histopathology and microangiography did not show any hemorrhage in the spinal cord of any of the specimens, although there were formation of perivascular space, rupture of a part of nerve fibers in the white matter and findings of acute degeneration in the grey matter. In the second part of this study, a small amount of distraction was introduced until the amplitude of the II deflection depicted transient augmentation, which had a mean amplitude of 167.8 per cent as compared to the control. This enhancement returned approximately to the normal value within 10 minutes by total release.(ABSTRACT TRUNCATED AT 400 WORDS)     

脊柱结核治疗若干问题探讨

随着HIV肆虐和免疫系统缺陷患者增加,全球结核病发病率,包括脊柱结核呈明显回升趋势。耐药性结核菌株的产生更是雪上加霜,“红魔再现(Red King revives)”已是不容否认的事实。中国是全球22个结核病高负担国家之一,每年新发病例占全球总数的16％。脊柱结核是最常见的骨关节结核,约占骨结核的50％,占全部结核病的3％～5％。对此,如诊治有误,可引起较高的致残率。因此,骨科医生对于脊柱结核的诊断与治疗这一历史课题必须再次引起重视。