机械牵张应力对骨化颈椎后纵韧带成纤维细胞的影响

目的探讨机械牵张应力对体外培养的颈椎后纵韧带骨化症（OPLL）患者颈椎韧带成纤维细胞的影响。方法对2012年1月至2013年12月 OPLL 与颈椎外伤但无后纵韧带骨化（非OPLL）患者（各15例）行前路颈椎手术治疗,术中取韧带标本。采用组织块培养法进行细胞体外培养,免疫细胞化学及免疫荧光技术检测胞质波形蛋白。采用 Flexercell 4000细胞加载培养系统分别对两组患者第3代细胞进行机械牵张应力加载,逆转录-聚合酶链式反应（RT-PCR）方法检测两组成纤维细胞应力刺激前及刺激后12、24 h 成骨特异性指标骨钙素、碱性磷酸酶与Ⅰ型胶原 mRNA 表达。结果免疫细胞化学及免疫荧光检测显示胞质波形蛋白呈阳性表达。OPLL组后纵韧带成纤维细胞经机械牵张应力刺激12 h后,骨钙素、碱性磷酸酶及Ⅰ型胶原 mRNA 表达明显升高,应力刺激前后差异具有统计学意义;而非OPLL组应力刺激前后骨钙素、碱性磷酸酶及Ⅰ型胶原 mRNA 表达无明显变化。结论机械牵张应力可促使OPLL患者后纵韧带成纤维细胞骨钙素、碱性磷酸酶及Ⅰ型胶原mRNA表达增加,促进其骨化,其在OPLL进展中发挥重要作用。     

应用负载碱性成纤维细胞生长因子的人脱细胞羊膜构建人工活性真皮

目的 探讨构建一种新型人工活性真皮的可行性.方法 组织块法培养幼儿包皮成纤维细胞;采用酶-去垢剂法制备人脱细胞羊膜(HAAM);双相法制备碱性成纤维细胞生长因子(bFGF)-明胶-壳聚糖缓释微球;缓释微球黏附于HAAM;bFGF基体式负载于HAAM,绘制药物缓释曲线;将第3～4代成纤维细胞培养于负载缓释微球的HAAM;扫描电镜观察HAAM、缓释微球的表面特征及缓释微球与HAAM的粘附情况;Western印迹法检测成纤维细胞中层粘连蛋白的表达.结果 制备的HAAM为白色半透明状薄膜,有较高的孔隙率,空隙不规则,孔径大小为10～100 nm,无细胞毒性;bFGF-明胶壳聚糖缓释微球分散较均匀,呈球形,粒径均匀,球体表面比较光滑,载药率为20 ng/g,包封率为80.5％,体外药物缓释曲线显示药物控释效果良好;成纤维细胞在支架表面爬行生长良好,层粘连蛋白表达较对照组高.结论 通过将成纤维细胞种植于负载bFGF-明胶-壳聚糖缓释微球的HAAM,有望制备出一种新型的人工活性真皮.     

脱细胞羊膜的制备及其生物相容性研究

目的制备脱细胞人羊膜(HAAM),检测其细胞相容性和组织相容性,探讨其作为组织工程支架材料的可行性. 方法新鲜人羊膜经漂洗后戊二醛交联,0.5%SDS震摇24小时,胰蛋白酶消化4小时,充分漂洗,冷冻干燥,分装,环氧乙烷消毒备用.倒置相差显微镜和扫描电镜观察表面结构,测量孔径,并作HE、Mallory染色.体外培养人成纤维细胞并复合于HAAM,倒置相差显微镜和扫描电镜观察细胞的黏附、生长,四甲基偶氮唑盐(MTT)法测定HAAM浸提液对培养的人成纤维细胞的细胞毒性.将HAAM植入SD大鼠背部皮下,观察其组织相容性. 结果 HAAM的一面为网状结构,孔径为10～80 nm,另一面为致密纤维结构.HE、Mallory染色表明材料无细胞残留,均为胶原组成.成纤维细胞能在HAAM上黏附、增殖.MTT示材料细胞毒性为0或1级,动物埋置实验无异常反应. 结论应用去垢剂-酶消化法处理新鲜人羊膜,能有效去除组织中的细胞和可溶性成分,可进一步降低其免疫原性,保留基质及网状结构,有良好的细胞相容性和组织相容性,可作为组织缺损的修复材料及组织工程的膜支架材料.     

基于生物信息学对脊髓损伤后关键微小RNA与转录因子的筛选及其靶基因预测

目的探讨脊髓损伤(SCI)后关键的微小RNA(miRNAs)与转录因子(TFs)并进一步了解miRNAs、TFs与靶基因的互作关系。方法从基因表达综合数据库(GEO)下载基因表达谱(GSE19890), 将差异倍数(log2FC)≥1和错误发现率(FDR)≤0.05作为标准阈值, 通过对微阵列数据分析筛选出差异表达的miRNAs(DEmiRNAs)。预测DEmiRNAs靶基因后分别进行京都基因与基因组百科全书(KEGG)通路和基因本体论(GO)功能富集分析, 接着基于TFs-靶基因互作分析确定关键的TFs, 根据靶基因的蛋白-蛋白互作网络分析确定特殊的DEmiRNA。结果通过对数据的分析, 分别与对照组相比, SCI后1 d出现5个下调基因和74个上调基因, 3 d后有118个下调基因和21个上调基因, 7 d后有450个下调基因和11个上调基因。韦恩在线分析筛选出7个重叠的DEmiRNAs参与了SCI后的表达调控。KEGG富集分析主要涉及细胞衰老、胰岛素抵抗和促性腺激素释放激素(GnRH)等信号通路, GO富集分析主要涉及RNA聚合酶Ⅱ启动子的转录正调控、基因表达的正调控和大脑发育等...     

微RNA-218通过抑制RUNX2及Ⅰ型胶原基因表达延缓后纵韧带骨化

目的探讨微RNA-218(mi RNA-218)对后纵韧带骨化症(OPLL)患者原代后纵韧带细胞骨化的影响及其作用机制。方法原代培养5例OPLL患者及5例非OPLL者的韧带细胞,比较2组细胞miRNA-218的表达差异。利用agomir过表达或antagomir抑制OPLL患者韧带细胞中miRNA-218的表达水平后进行成骨诱导,通过检测茜素红染色水平、碱性磷酸酶活性及成骨相关基因的表达验证miRNA-218对韧带细胞骨化的作用。采用Target scan预测miRNA-218的靶基因,并采用双荧光素酶报告基因实验验证miRNA-218的靶向作用。结果 OPLL患者韧带细胞miRNA-218的表达水平低于非OPLL者,差异有统计学意义(P 0.05)。过表达miRNA-218后OPLL患者韧带细胞茜素红染色水平、碱性磷酸酶活性及成骨相关基因的表达均低于对照组;抑制miRNA-218后OPLL患者韧带细胞茜素红染色水平、碱性磷酸酶活性及成骨相关基因的表达均高于对照组;差异均有统计学意义(P 0.05)。Target scan预测miRNA-218靶基因可能为RUNX2和Ⅰ型胶原(COL1A1),双荧光素酶报告基因实验显示miRNA-218能降低RUNX2及COL1A1基因的荧光素酶活性水平。结论 miRNA-218能明显抑制原代后纵韧带细胞的骨化反应,其作用机制与抑制RUNX2和COL1A1基因表达相关。     

脊柱韧带骨化发病机制研究进展

脊柱韧带骨化的病因及发病机制尚不明确。机械应力、元素含量、内分泌水平、遗传等多因素共同参与脊柱韧带骨化的发生和发展。近年来,出现了较多关于对机械应力刺激高度敏感的韧带组织或细胞相关机制的研究,细胞外基质-整合素-细胞骨架途径在信号转导中的作用引起广泛重视,一系列新的成骨相关生长因子、转录因子及基因多态性位点等陆续被发现。该文对近年来脊柱韧带骨化发病机制研究进展作一综述。     

颈椎后纵韧带骨化细胞体外培养及成骨活性检测

目的探讨体外培养颈椎后纵韧带骨化(ossification of posterior longitudinal ligament,OPLL)患者韧带细胞的方法并检测其成骨活性。方法 2013年1~12月颈椎外伤与后纵韧带骨化患者各15例行颈前路手术治疗。术中切取韧带标本,采用组织块培养法进行体外培养。取第3代细胞进行细胞鉴定,逆转录聚合酶链反应方法测量2组细胞骨钙素、碱性磷酸酶与Ⅰ型胶原mRNA表达差异。结果组织块培养法培养7~14 d见细胞萌出,细胞呈梭形、纺锤形及多角的星形,细胞核大、卵圆形、细胞边界不清。免疫细胞化学及免疫荧光检测显示波形蛋白阳性表达,证实细胞培养成功。逆转录聚合酶链反应结果提示韧带骨化组细胞骨钙素、碱性磷酸酶与Ⅰ型胶原mRNA表达明显高于外伤组。结论组织块培养法可成功培养颈椎后纵韧带组织细胞,形态学表现为成纤维细胞特点。体外培养的OPLL患者的韧带细胞具有明显的成骨活性。     

强直性脊柱炎棘上棘间韧带的扫描电镜与成纤维细胞培养研究

目的 观察强直性脊柱炎（AS）棘上棘间韧带的超微结构和探讨成纤维细胞在韧带骨化中的作用。找出AS韧带中胶原紊乱排列和钙颗粒沉积是否由成纤维细胞活动引起。方法 采用扫描电镜－X线能谱仪联机对AS脊柱韧带进行观察。采用细胞培养法对AS棘上棘间韧带成纤维细胞进行体外培养,显微观察和组化染色特等。结果 扫描电镜显示韧带上的胶原排列紊乱,其间有钙颗粒沉积,X线能谱能显示出钙峰,细胞培养观察到AS成飨维细胞增残活跃,分泌颗粒旺盛。细胞经AlcainBlue,甲苯胺蓝,ARS染色均呈阳性反应。AKP酶测试亦显示有多量AKP存在于胞体内外。结论 AS的成纤维细胞能分泌各种成骨基质。AS脊柱韧带中的胶原纤维排列紊乱和钙沉积与该细胞的活动密切相关。     

利用微阵列芯片技术筛选主动脉夹层致病相关基因

目的 应用微阵列芯片技术观察主动脉夹层(Stanford B型)基因表达谱的变化,筛选差异表达基因,寻找致病相关基因.方法 选取急性期的主动脉夹层(AD)标本6例,以6例正常胸主动脉作对照.抽提标本总RNA,纯化mRNA后逆转录,制备杂交探针,采用Phalanx人类全基因组芯片进行检测,应用DAVID、Pathway studio 5.0、SAM 3.01等软件对微阵列芯片的结果进行统计学、聚类和差异表达分析.选取两组间差异表达的7个基因,采用Real time PCR验证微阵列芯片结果.结果 共得到6375个基因的有效数据,其中670个差异表达基因,AD组218个基因发生上调,452个基因发生下调;其中14个基因参与细胞间黏附;12个基因参与细胞外基质的生成;4个基因参与细胞与细胞外基质间黏附;14个基因参与细胞外骨架的组成;10个基因参与免疫与炎症反应;10个基因参与胶原合成;12个基因参与细胞凋亡.Real time PCR验证结果和微阵列芯片所得数据一致.结论 AD的发生伴随着多个基因的差异表达,微阵列芯片筛选差异表达基因,有助于找到与AD致病相关的基因;上述基因的差异表达可能是AD的重要发病机制.     

成人黄韧带细胞的体外培养

目的:探讨成人黄韧带细胞的体外培养方法,为研究黄韧带退变的发病机制奠定基础。方法:采集成年胸腰椎骨折患者后路减压术中的黄韧带,应用胶原酶预消化组织块培养法分离黄韧带细胞,并传代培养;倒置相差显微镜下观察细胞从组织块内迁出时间、细胞形态和生长状态;传1、3、5代细胞培养1～8d,用四甲基偶氮唑盐比色法(MTT)测定其吸光度(OD)值,评价细胞增殖状况,并绘制细胞生长曲线;用免疫荧光染色法检测传3代细胞的波形蛋白和Ⅰ型胶原的表达。结果:在原代培养第10～14天,黄韧带细胞开始从组织块迁出,细胞呈多种形态,主要为梭形和多角形,细胞接近融合时呈涡流状生长。传1、3、5代细胞生长曲线呈S形,同一代细胞在不同时间点的OD值差异有统计学意义(P0.001),同一时间点不同代次细胞的OD值无统计学差异(P0.05),细胞代次与时间点间无交互效应,各代细胞增殖状况无统计学差异(F=0.283,P=0.957)。传3代细胞的波形蛋白和Ⅰ型胶原免疫荧光染色呈阳性。结论:胶原酶预消化组织块培养法能有效分离成人黄韧带细胞;体外培养的黄韧带细胞呈成纤维细胞样表型,细胞在传5代以内生物学特性稳定。     

膀胱癌组织中miRNA-720、miRNA-191差异表达的意义

目的 探讨miRNA-720、miRNA-191在膀胱癌中差异表达的意义。方法 取手术切除的24例新鲜膀胱癌组织（T1~4）及12例前列腺增生患者膀胱组织保存于液氮中,Trizol试剂提取总RNA,NanoDrop 2000及变性琼脂糖凝胶电泳进行RNA检测,用标记酶Hy3TM荧光基团标记RNA的探针和miRCURYTM芯片杂交,GenePix 4000B芯片扫描仪及GenePix pro V6.0进行图像采集和数据分析,对差异表达的miRNA进行检测,实时定量逆转录PCR（qRT-PCR）对部分差异表达的miRNA进行验证。结果 与正常膀胱黏膜组织比较,非浸润性膀胱癌组织中有77个miRNA表达增加,72个表达降低;浸润性膀胱癌组织中有42个miRNA表达增加,104个表达降低。qRT-PCR检测证实miRNA-720和miRNA-191的表达水平与基因芯片结果一致。结论 非浸润性和浸润性膀胱癌组织中miRNA的差异表达普遍存在,miRNA-720可以作为膀胱癌检测的一个组织标志物,而miRNA-191在浸润性膀胱癌中的表达水平较非浸润性膀胱癌低（P〈0.05）,可作为膀胱癌是否浸润肌层的一个组织标志物。     

miRNA在绝经后骨质疏松症肾阴虚证中的表达谱特征及生物信息学分析

目的探讨绝经后骨质疏松症(postmenopausal osteoporosis,PMOP)肾阴虚证miRNA的表达谱特征,及对差异表达的miRNA进行生物信息学分析。方法随机选择绝经后骨质疏松症受试者,中医辨证,分为3组:PMOP肾阴虚组3例,PMOP肾阳虚组3例,健康绝经后妇女3例作为对照组。采用人miRNA芯片检测外周血单个核细胞miRNA的表达水平。肾阴虚证组分别与其他两组比较,筛选共同的差异表达基因,实时荧光定量PCR验证芯片结果,并对差异表达的miRNA进行pathway分析及靶基因预测。结果肾阴虚证组与对照组、肾阳虚证组两组比较,筛选出20条共同差异表达miRNA;实时定量PCR验证hsa-miR-411-5p、hsa-miR-143-3p、hsa-miR-95-3p表达的结果与芯片结果相符;pathway分析结果显示,这些差异miRNA主要参与代谢通路、癌症通路、Rap1信号通路、粘着斑信号通路、PI3K-Akt、MAPK信号通路、钙离子信号通路、内质网蛋白加工、c GMP-PKG信号通路、Ras信号通路、Wnt信号通路的调控;结合多个数据库对差异表达的miRNA进行靶基因预测,最终筛选出9个靶基因(RC3H1、SOX11、FUT4、GABRA4、NUFIP2、ONECUT2、PHF20、PURB、ZNF148)。结论建立了PMOP肾阴虚证的miRNA基因表达谱,且这20个差异表达的miRNA可能通过调控PI3K-Akt、MAPK、Wnt等与骨代谢相关信号通路参与PMOP肾阴虚证的发生发展过程。     

Spinal cord compression caused by unusual location and extension of ossified ligamenta flava in a Caucasian male. A case report and literature review

STUDY DESIGN: A case report of a spinal cord compression caused by ossification of the ligamenta flava is presented together with a review of the literature. OBJECTIVE: To present the diagnosis of ossification of the ligamenta flava in a Caucasian man with a proximal thoracic myelopathy. SUMMARY OF BACKGROUND DATA: This case shows that the upper parts of the thoracic spine can be involved in ossification of the ligamenta flava, which never before has been reported in Caucasian individuals. Furthermore, it is advised that computed tomography scanning and magnetic resonance imaging be combined to provide an accurate diagnosis and proper preoperative evaluation of the bony changes, spinal cord, and compression of the spinal cord. METHODS: A patient with a thoracic spinal cord compression caused by ossification of the ligamenta flava was treated surgically and made a good clinical recovery. Imaging studies, surgical findings, and results of histopathologic investigations were analyzed to substantiate the diagnosis. RESULTS: The results of the surgical findings seemed to be in contrast with those of the imaging studies. This contrast was occasioned by the uncommon perioperative finding of a fusion of the completely ossified upper and lower parts of the involved adjacent ligamenta flava. Ossification of the ligamenta flava was diagnosed by histopathologic examination, which revealed endochondral ossification and lamellar bone formation without fragments of ligamenta flava. CONCLUSION: Although rarely reported in whites, ossification of the ligamenta flava should be considered in all patients presenting with a spinal cord compression, even at high thoracic levels. The prognosis after decompressive surgery can be good, especially if intramedullary hyperintensities are absent on preoperatively performed T2-weighted magnetic resonance images.     

急性腰椎黄韧带皱褶嵌入椎管狭窄症的手术治疗

目的探讨无椎间盘突出症(LDH)的急性腰椎黄韧带皱褶嵌入椎管狭窄症的手术治疗远期疗效。方法解剖人脊柱腰骶段35例,对黄韧带的后方毗邻及椎板内聚黄韧带皱褶嵌入作了较细致的观察,同时手术探查无椎间盘突出症者行小切口椎板内聚黄韧带皱褶突出处切除椎管减压术。结果观察的人脊柱腰段35例,对黄韧带的分布,建议使用"盘-黄间隙"一词并对国内外LDH插图提出修改意见。对224例LDH中28例急性腰椎黄韧带皱褶嵌入椎管狭窄症者行手术治疗。随访5～12年,本组治愈率为89.3%。结论探查腰椎无椎间盘突出时,应考虑到由于椎板内聚而致黄韧带皱褶的嵌入所致的类似腰椎间盘突出症症状。但有合并症者应同时处理。本术式是一种远期疗效较高的安全及微创手术。     

microRNA-186-5p及其靶基因CLDN18与甲状腺乳头状癌复发风险的关系

背景与目的：microRNA（miRNA）在肿瘤的发生、发展中发挥重要作用,而且不同的miRNA表达状态与肿瘤的不同生物学特征紧密关联。本研究通过分析不同复发风险甲状腺乳头状癌（PTC）患者差异表达的miRNA,筛选与PTC复发风险相关的miRNA,并分析其作用机制。 方法：用基因芯片技术分析低危复发风险与中高危复发风险PTC患者血清外泌体中差异表达的miRNA,然后用qRT-PCR方法PTC患者肿瘤组织中验证;用Transwell实验筛选出与PTC细胞侵袭能力有关的差异表达miRNA。通过OncomiR在线数据库对筛选的细胞侵袭力相关miRNA的靶基因进行预测,随后采用过表达与敲低策略,分析PTC细胞相关蛋白表达（Western blot）与PTC细胞侵袭能力（Transwell）的变化,明确细胞侵袭力相关miRNA与预测靶基因的关系。最后,通过GEPIA在线网站对TCGA数据库中PTC临床样本的分析进一步确证。 结果：基因芯片分析结果显示,与低危复发风险PTC患者比较,中高危复发风险PTC患者血清外泌体中4个miRNA（miR-186-5p、miR-532-3p、miR-199b-3p、miR-3158-5p）表达上调,1个miRNA（miR-3605-5p）表达下调（均P<0.05）;组织标本qRT-PCR验证结果显示,中高危复发风险PTC患者癌组织中miR-186-5p和miR-3158-5p表达上调（均P<0.05）;Transwell实验结果显示,过表达miR-186-5p后PTC细胞侵袭能力明显增强,敲低则明显减弱（均P<0.05）,但改变miR-3158-5p的表达水平对PTC细胞的侵袭能力无明显影响（均P>0.05）。OncomiR在线数据库预测PRDX6、S100PBP、CLDN18、MAP2可能是miR-186-5p的靶基因;Western blot结果显示,过表达miR-186-5p后PTC细胞中CLDN18的蛋白表达明显降低,敲低则相反,但改变miR-3158-5p的表达水平对其他3个基因的蛋白表达无明显影响;Transwell实验结果显示,过表达CLDN18表达后PTC细胞的侵袭能力明显减弱,敲低则明显增强,而过表达或敲低miR-186-5p对PTC细胞的作用被同时过表达或敲低CLDN18所逆转（均P<0.05）。TCGA数据库分析结果显示,PTC组织中CLDN18表达较正常甲状腺组织明显降低。 结论：miR-186-5p表达的增高可能与PTC的复发风险密切相关,机制可能与其通过调节下游CLDN18基因的表达而影响PTC细胞的侵袭能力有关。     

Ossification of ligamentum flavum unmasked by acute paraplegia

A 30-year-old black man presented sudden-onset paraplegia during a foot-ball match, after a movement of hyperextension of the trunk. Moreover, the patient exhibited an hypoesthesia below the T11 level, with sphincter disturbances. The MRI and the CT-scan showed a stenosis of the spinal canal related to an ossification of hypertrophied ligamenta flava from T10 to T12. Intramedullary abnormal signals on MRI images were compatible with a spinal cord hemorrhage. A laminectomy with removal of abnormal ligamenta flava was carried out, and their endochondral ossification was confirmed by pathological examination. Two months later, the patient was able to walk alone and exhibited a mild spasticity associated to sensory disturbances of lower limbs. Ossification of ligamenta flava is usually observed in Japanese patients, sometimes in Caucasians, more rarely in black people. Its mechanism is unclear except when associated with metabolic or endocrine diseases. The patients usually present with clinical features of chronic spinal cord compression. Our case seems to be the first one disclosed by an acute spinal cord injury on ossified ligamenta flava. In this patient, because of remaining adjacent ossified ligamenta flava and the development on postoperative MRI of an intramedullary cavity, a long-term clinical and radiological follow-up is particularly necessary.     

Cervical radiculomyelopathy due to calcification of the ligamenta flava

Three cases of cervical radiculomyelopathy caused by calcification of the ligamenta flava of the cervical spine are reported. A review of the literature yielded 13 cases of calcification of the cervical ligamenta flava with findings similar to those in our cases. Specifically, we observed that 1) all patients were more than 50 years of age; 2) most were female; and 3) the calcifications appeared consistently as oval nodules, located symmetrically and paramedially in and around the region of the fifth cervical vertebra. Such characteristic similarities in both clinical and radiologic features are important in considering the etiology of calcification of the cervical ligamenta flava.     

Cervical radiculomyelopathy caused by deposition of calcium pyrophosphate dihydrate crystals in the ligamenta flava. Case report

A case of cervical radiculomyelopathy caused by multiple calcified nodules in the ligamenta flava is presented. Roentgenological examination of the cervical spine showed radiopaque nodular lesions, 7 x 7 x 5 mm in size, located in the paramedian portion of the posterior spinal canal. The nodules were removed surgically and they were confirmed to be calcifications of ligamenta flava. Microscopic examination of the nodules with the polarized light revealed extensive deposition of crystals. By x-ray diffraction study, the crystal was determined as calcium pyrophosphate dihydrate (CPPD: Ca2P2O7 . 2H2O). Although CPPD deposition in the cartilage has been known as pseudo-gout syndrome, deposition in the ligament has been reported only in a few cases. This is the first case with radiopaque calcified nodules in the ligamenta flava causing spinal cord compression, the composition of which proved to be CPPD.     

Ossification of the proximal thoracic ligamenta flava causing acute myelopathy in a Caucasian: case report and literature review

STUDY DESIGN: Case report and literature review. OBJECTIVE: To illustrate that ossification of the proximal thoracic ligamenta flava can be a rare cause of acute myelopathy in a Caucasian patient and that timely surgery can lead to a good outcome. SETTING: Nottingham, UK. METHODS: Proximal multiple contiguous ossified thoracic ligamenta flava from T3/T4 to T5/T6 causing acute myelopathy was diagnosed in a Caucasian man based on history and examination followed by magnetic resonance imaging and computed tomography scanning. The literature is reviewed for all reported cases of ossified ligamenta flava causing myelopathy in Caucasians. RESULTS: Following prompt diagnosis and T3 to T5 laminectomies, our patient made near-complete neurological recovery over a 10-month period. This condition usually affects the lower thoracic spine. Although chronic and subacute myelopathy secondary to this circumstance has been reported in Caucasians, acute myelopathy has not been reported and proximal thoracic involvement has been reported twice. CONCLUSION: Ossification of the proximal thoracic ligamenta flava can be a rare cause of acute myelopathy in Caucasians. Prognosis following decompressive surgery is usually good.     

Topographical anatomy of the lumbar epidural region: an in vivo study using computerized axial tomography

The lumbar epidural region was studied using computerized tomography. This technique allows examination of the region in vivo. It confirmed that the spinal canal is oval in the upper lumbar region, becoming triangular lower down, and that the ligamenta flava form a posterior recess to the vertebral canal. Epidural fat is confined to this region between the ligamenta flava and the intervertebral foramina, and the dura mater lies apposed to the walls of the vertebral canal except where there is epidural fat. The absence of a posterior midline fold of dura mater was noted, and discussed in the light of other studies.