椎间盘造影中碘海醇剂量对大鼠椎间盘退行性变的影响

目的 探讨椎间盘造影中造影剂碘海醇剂量对椎间盘退行性变的影响。方法 以10只成年雄性SD大鼠的40个尾椎椎间盘（每只4个）为实验对象,分为空白组（Co₆/Co₇）、对照组（Co₇/Co₈）、常规剂量组（Co₈/Co₉,2 μL碘海醇）和高剂量组（Co₉/Co₁₀,3 μL碘海醇）。分别于椎间盘造影术后2周和4周使用X线检测椎间高度指数（DHI）,使用MRI评估椎间盘信号;术后4周检测椎间盘含水量,并采用HE染色检测组织学变化。结果 术后2周和4周时,与空白组相比,对照组DHI未见明显变化,常规剂量组和高剂量组DHI降低,且高剂量组比常规剂量组降低更为显著,差异均有统计学意义（P < 0.05）;对照组、常规剂量组和高剂量组椎间盘信号均降低,且剂量越大信号越低,差异均有统计学意义（P < 0.05）。与空白组相比,对照组椎间盘含水量未见明显变化,常规剂量组和高剂量组椎间盘含水量降低,且高剂量组降低更为显著,差异均有统计学意义（P < 0.05）。与空白组相比,对照组椎间盘组织学评分无明显变化,常规剂量组和高剂量组椎间盘组织学评分均增高,且剂量越大评分越高,差异均有统计学意义（P < 0.05）。结论 椎间盘造影时注入碘海醇可促进椎间盘退行性变,且呈剂量依赖性。在造影操作时应尽量减少造影剂的使用,以降低对椎间盘的影响。     

In vitro measurement of pressure in intervertebral discs and annulus fibrosus with and without annular tears during discography

BACKGROUND CONTEXT: Discogram studies have shown that pain reproduction correlates with the extent of annular disruption. However, it has not been assessed if pressure changes in the annulus fibrosus vary incrementally with intradiscal pressure. PURPOSE: To determine the relationship between intradiscal pressure and outer annular pressure during discography in intervertebral discs with and without annular tears. STUDY DESIGN: Intradiscal and periannular pressures were measured simultaneously in vitro during intradiscal injection in porcine cadaver spines. METHODS: Twenty fresh porcine cadaver lumbar spines with intervening discs were tested. Intradiscal and periannular pressures were measured simultaneously using two pressure sensors during intradiscal contrast injection. The tip of a 25-gauge needle connected with a pressure manometer was placed in the center of the nucleus pulposus. A second pressure transducer was located at the outer third of the annulus fibrosus. Needle and transducer locations were confirmed by fluoroscopy. To compare the intact and torn annulus fibrosus, annular disruptions were created with a 20-gauge needle and confirmed by fluoroscopy. RESULTS: During intradiscal injections of discs with an intact annulus, annulus fibrosus pressure remained low and a sharp increase in intradiscal pressure was observed. Significantly higher pressures were noted in the outer annulus in discs with annular tears (p<.01). Mean pressures at the central nucleus pulposus, the outer third of intact annuli and torn annuli were 93.4+/-40.9 psi, 14.8+/-1.9 psi and 85.7+/-24.8 psi, respectively. CONCLUSIONS: Volumetric injection of intervertebral discs with a torn annulus fibrosis during discography may increase intra-annular pressure similar to the increase in pressure that may occur during spinal loading activities. This effect may not occur in discs with an intact annulus fibrosus.     

椎间失稳致兔椎间盘退变磁共振影像计量分析

目的 :探讨由于椎间失稳诱发的椎间盘退变在磁共振成像 (magneticresonanceimaging ,MRI)中的表现。方法 :选用新西兰兔 15只 ,随机分为手术组 9只、对照组 6只 ,手术组沿L3～ 6棘突作后正中切口 ,剥离骶棘肌和关节突附丽肌肉 ,切除棘上、棘间韧带和关节突关节外后 1/ 2 ;对照组作相同皮肤切口即缝合。所有动物在标准条件下饲养 ,分别于术后 2、 4、 8个月行腰椎MRI检查及髓核信号值测量。结果 :术后 2～ 8个月 ,对照组腰椎未见异常 ,而手术组L3～ 6椎间盘则相继出现T2 加权像低信号、腰椎后凸畸形、T1加权像低信号、椎间盘后突和硬膜囊受压等改变。对手术组手术节段及其邻近节段椎间盘髓核信号值的定量分析显示 ,T2 加权像信号值减低在术后 2、 4、8个月均具有统计学意义 ,而T1加权像信号值减低在术后 8个月具有统计学意义 ;T2 信号值减低主要发生于术后 2个月 ,T1信号值减低发生于术后 8个月。结论 :脊柱失稳可诱发椎间盘退变。髓核T2 加权像低信号是椎间盘退变的早期和先发征象 ,T1加权像显示形态改变较好 ,但T1信号值在退变早期变化不明显。     

Influence of lumbar intervertebral disc degeneration on the outcome of total lumbar disc replacement: a prospective clinical, histological, X-ray and MRI investigation

Introduction

The role of fusion of lumbar motion segments for the treatment of axial low back pain (LBP) from lumbar degenerative disc disease (DDD) without any true deformities or instabilities remains controversially debated. In an attempt to avoid previously published and fusion-related negative side effects, motion preserving technologies such as total lumbar disc replacement (TDR) have been introduced. The adequate extent of preoperative DDD for TDR remains unknown, the number of previously published studies is scarce and the limited data available reveal contradictory results. The goal of this current analysis was to perform a prospective histological, X-ray and MRI investigation of the index-segment’s degree of DDD and to correlate these data with each patient’s pre- and postoperative clinical outcome parameters from an ongoing prospective clinical trial with ProDisc II (Synthes, Paoli, USA).

Materials and methods

Nucleus pulposus (NP) and annulus fibrosus (AF) changes were evaluated according to a previously validated quantitative histological degeneration score (HDS). X-ray evaluation included assessment of the mean, anterior and posterior disc space height (DSH). MRI investigation of DDD was performed on a 5-scale grading system. The prospective clinical outcome assessment included Visual Analogue Scale (VAS), Oswestry Disability Index (ODI) scores as well as the patient’s subjective satisfaction rates.

Results

Data from 51 patients with an average follow-up of 50.5 months (range 6.1–91.9 months) were included in the study. Postoperative VAS and ODI scores improved significantly in comparison to preoperative levels (p < 0.002). A significant correlation and interdependence was established between various parameters of DDD preoperatively (p < 0.05). Degenerative changes of NP tissue samples were significantly more pronounced in comparison to those of AF material (p < 0.001) with no significant correlation between each other (p > 0.05). Preoperatively, the extent of DDD was not significantly correlated with the patient’s symptomatology (p > 0.05). No negative influence was associated with increasing stages of DDD on the postoperative clinical outcome parameters following TDR (p > 0.05). Increasing stages of DDD in terms of lower DSH scores were not associated with inferior clinical results as outlined by postoperative VAS or ODI scores or the patient’s subjective outcome evaluation at the last FU examination (p > 0.05). Conversely, some potential positive effects on the postoperative outcome were observed in patients with advanced stages of preoperative DDD. Patients with more severe preoperative HDS scores of NP samples demonstrated significantly lower VAS scores during the early postoperative course (p = 0.02).

Conclusion

Increasing stages of DDD did not negatively impact on the outcome following TDR in a highly selected patient population. In particular, no preoperative DDD threshold value was identified from which an inferior postoperative outcome could have been deduced. Conversely, some positive effects on the postoperative outcome were detected in patients with advanced stages of DDD. Combined advantageous effects of progressive morphological structural rigidity of the index segment and restabilizing effects from larger distraction in degenerated segments may compensate for increasing axial rotational instability, one of TDR’s perceived disadvantages. Our data reveal a “therapeutic window” for TDR in a cohort of patients with various stages of DDD as long as preoperative facet joint complaints or degenerative facet arthropathies can be excluded and stringent preoperative decision making criteria are adhered to. Previously published absolute DSH values as contraindication against TDR should be reconsidered.     

Evaluation of cervical disc degeneration with ultralow field MRI and discography. An experimental study on cadavers

The purpose of this study was to test the value of low-field magnetic resonance imaging (MRI) and discography in visualizing disc degeneration of the cervical spine. Plain roentgenograms, MR images, discograms, and macroanatomic appearance of the cervical spines of ten cadavers were compared. At levels C4-5-C7-T1, general disc degeneration seen in discography correlated well with macroanatomy (weighted kappa (Kw) = 0.77). The nuclear shape in MRI showed a weak correlation with macroanatomy (Kw = 0.31) and general disc degeneration in discography (Kw = 0.32), whereas nuclear intensity in MRI underestimated such changes. Magnetic resonance imaging showed posterior extension of the nucleus in most cases where moderate or severe leaking was seen in discography. The latter phenomenon represents an increase to our information on structural changes not available by any other noninvasive and nonirradiative method of examination.     

The effect of discography on the canine intervertebral disc

With increasing use of chemonucleolysis, interest and use of discography is at an all-time high. Various reports in past years have disagreed on the safety and efficacy of intradiscal injections of contrast mediums. This experimental study was devised to determine the effects of discography on the gross and histologic appearance of the lumbar intervertebral disc. Through a laparotomy approach, five lumbar discs in ten dogs were exposed. In each dog, one disc served as a control, another punctured with a needle, and the others injected with metrizamide, hypaque, or saline, At 2, 4, 6, 8, and 10 weeks postoperative, two dogs were killed at each time interval. Examination of the discs revealed no gross differences between any of the groups. The normal gross architecture of the concentric annulus and gelatinous nucleus was maintained in all specimens. This study found no evidence that discography results in gross or histologic damage to the intervertebral disc. It does not appear that discography will predispose a normal intervertebral disc to herniate. Discography alone appears to be a safe diagnostic procedure with no experimental evidence of any untoward gross or histologic effects.     

腰椎终板、椎间盘退变及椎间盘造影疼痛激发试验的相关性研究

目的探讨下腰痛患者腰椎终板Modic退变、椎间盘退变及CT引导下腰椎间盘造影疼痛激发试验的相关性.方法对45例下腰痛患者常规行腰椎X线和MR检查,分别按Modic终板退变标准（0～3级）与Pearce椎间盘退变标准（Ⅰ～Ⅴ级）对终板和椎间盘进行评估.在CT引导下对45例患者中的40例（120个椎间盘）进行造影和疼痛激发试验,并按Dallas椎间盘造影分级系统（DDD）测评椎间盘退变程度.采用SPSS 11.5统计学软件分析腰椎终板Modic退变、椎间盘退变与腰椎间盘造影疼痛激发试验之间的相关性.结果40例下腰痛患者的腰椎终板Modic分级与椎间盘退变Pearce分级存在较强的相关性（Pearson x^2=43.326,P=0.000）,与椎间盘造影疼痛激发试验有显著相关性（Pearson x^2=27.858,P=0.000）;椎间盘退变Pearce分级与CT椎间盘造影椎间盘退变Dallas分级也呈较强的相关性.结论腰椎终板Modic退变分级与椎间盘退变Pearce分级密切相关,而与椎间盘疼痛激发试验有显著相关性,提示终板Modic退变可能是下腰痛的原因之一.     

A critical evaluation of discography in patients with lumbar intervertebral disc disease

STUDY DESIGN: The study is a prospective observational study of 48 continuous patients with symptomatic lumbar degenerative disk disease. Each patient underwent discography, MRI, and a biochemical analysis of disk lavage fluid. OBJECTIVES: The purpose of this study was to correlate concordant pain on discography with MRI grade and biochemical markers of inflammation in a clinical setting. SUMMARY OF BACKGROUND DATA: The pathophysiology of degenerative disk disease is complex. Discography is used to differentiate symptomatic from asymptomatic levels. MRI is used to image changes in disk water content. Biochemical assays have identified molecular markers of inflammation. To date, no study has correlated concordant pain on discography with MRI findings and biochemical markers. METHODS: Forty-eight (48) continuous patients with symptomatic lumbar degenerative disk disease gave informed consent for study entry. Patient sex, age, insurance, work status and visual analog score (VAS) were recorded. MRI was obtained and Pfirrmann grading was performed by a single spine surgeon. Discography with disc lavage was performed by a single anesthesiologist. Lavage samples were tested for inflammatory markers with high resolution multi-plex bead immunoassays and ELISA with >5 pg/ml resolution. RESULTS: None of demographic variables was significantly related to concordant pain on discogram by chi-squared tests and Mann-Whitney U-test. The Pfirrmann score was significantly different for patients with and without concordant pain at L3-L4 (p<0.001), but was insignificant at other levels after multitest correction. Pfirrmann scores were significantly different at any level in patients with and without concordant pain. VAS scores were not significantly correlated with opening pressures at any level. Despite the presence of serum proteins in the disk lavage fluid, none of the tested inflammatory mediators was identified by multi-plex bead immunoassays and ELISA. CONCLUSIONS: There are only weak correlations between demographic, discogram, and radiographic variables. Response to discogram cannot be predicted by non-invasive means. The disk lavage method was unable to identify the presence of specific inflammatory peptides with multi-plex immunoassays and ELISA.     

椎体终板与椎间盘退变

椎间盘退变是导致下腰痛的常见原因,与之密切相关的椎体终板退变也逐渐受到重视.MRI的T1和T2加权像上,退变的椎体终板表现为终板与终板下骨相对于正常终板的信号改变,且与对应的椎间盘退变有较高的相关性.经椎体终板的弥散是椎间盘获得营养的主要途径,同时椎体终板又是脊柱运动单位中最容易受损伤的部位,轴向负荷可导致软骨终板、骨性终板及终板下骨小梁弯曲变形,软骨终板与骨性终板分离.这一系列的终板损伤和软骨终板钙化和骨化会妨碍椎间盘营养供应,导致椎间盘组织学退变.新近研究进一步表明椎体终板与椎间盘退变不仅在组织学上密切相关,而且在力学上也密不可分,椎板形状如曲率也与椎间盘退变和突出存在一定的关联.     

1991 Volvo Award in clinical sciences. Smoking and lumbar intervertebral disc degeneration: an MRI study of identical twins

The primary objective of this study was to determine whether disc degeneration, as assessed through magnetic resonance imaging, is greater in smokers than in nonsmokers. To control for the maximum number of potentially confounding variables, pairs of identical twins highly discordant for cigarette smoking were selected as study subjects. Data analyses revealed 18% greater mean disc degeneration scores in the lumbar spines of smokers as compared with nonsmokers. The effect was present across the entire lumbar spine, implicating a mechanism acting systemically. This investigation demonstrates the efficiency of using carefully selected controls in studying conditions of multifactorial etiology, such as disc degeneration.     

炎症因子与椎间盘退变

椎间盘退变是导致腰背痛的主要原因之一.研究证明,肿瘤坏死因子-α、白细胞介素-1β、前列腺素E2、环氧化酶-2、一氧化氮等炎症因子在椎间盘退变进程中起重要作用.它们主要通过引起炎症反应、诱导细胞凋亡等途径促进椎间盘退变,同时各种炎症因子之间还可相互影响.针对性地阻断退变椎间盘中炎症因子的作用途径,抑制其引起的炎症反应,减少椎间盘细胞凋亡,对于延缓椎间盘退变进程,减轻患者临床症状具有重要意义.     

炎性因子与椎间盘退变

椎间盘退行性变是腰腿痛的重要原因之一,其特征性改变是髓核中蛋白多糖特别是聚合体含量下降、胶原类型的改变及伴随的水分的丢失。目前,椎间盘退变的原因尚不完全清楚,白介素(IL)、肿瘤坏死因子-α(TNF -α)等炎性细胞因子(简称炎性因子)具有促进椎间盘蛋白多糖降解和抑制其合成,参与椎间盘炎症反应等作用,极可能在椎间盘退变及其继发性疾病发病机制中起重要的作用。1　椎间盘中的炎性因子及其来源和影响因素体内检测到的众多炎性因子中,IL - 1、IL - 6、IL - 8、IL - 10、TNF -α、干扰素-γ(IFN -γ)及集落刺激因子(GM -CSF)等…     

MRI evaluation of spontaneous intervertebral disc degeneration in the alpaca cervical spine

Animal models have historically provided an appropriate benchmark for understanding human pathology, treatment, and healing, but few animals are known to naturally develop intervertebral disc degeneration. The study of degenerative disc disease and its treatment would greatly benefit from a more comprehensive, and comparable animal model. Alpacas have recently been presented as a potential large animal model of intervertebral disc degeneration due to similarities in spinal posture, disc size, biomechanical flexibility, and natural disc pathology. This research further investigated alpacas by determining the prevalence of intervertebral disc degeneration among an aging alpaca population. Twenty healthy female alpacas comprised two age subgroups (5 young: 2–6 years; and 15 older: 10+ years) and were rated according to the Pfirrmann‐grade for degeneration of the cervical intervertebral discs. Incidence rates of degeneration showed strong correlations with age and spinal level: younger alpacas were nearly immune to developing disc degeneration, and in older animals, disc degeneration had an increased incidence rate and severity at lower cervical levels. Advanced disc degeneration was present in at least one of the cervical intervertebral discs of 47% of the older alpacas, and it was most common at the two lowest cervical intervertebral discs. The prevalence of intervertebral disc degeneration encourages further investigation and application of the lower cervical spine of alpacas and similar camelids as a large animal model of intervertebral disc degeneration. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1776–1783, 2015.     

感染性椎间盘炎的MRI诊断及临床综合治疗

目的：探讨感染性椎间盘炎的MRI诊断价值及临床综合治疗。方法：搜集经MRI诊断，临床或手术病理证实的感染性椎间盘炎20例进行回顾性分析。全部病例均采用美国GE signa contruo0．5T超导MR扫描仪检查，常规SE序列，矢状位，T1WI，T2WI。8例采用钆喷酸葡甲胺（Gd—DTPA）增强扫描。20例感染性椎间盘炎患者中有25个椎间盘感染，其中单纯腰椎间盘感染17例，腰骶椎椎间盘同时感染3例。将20例患者随机分为治疗组和对照组，治疗组急性期采用大剂量抗生素冲击疗法并内服活血化瘀，消炎补肾，通络止痛等中药；慢性期采用中药熏洗，超短波理疗及远红外线热疗等。对照组急性期采用常规剂量抗生素治疗，慢性期采用理疗等方法。结果：①MRI结果：急性期14例，MRI表现为病变椎间盘，边缘模糊，呈略长T1、长T2信号。部分椎间盘破坏或碎裂，相邻椎体及软组织受累亦呈略长T1、T2信号。慢性期6例，MRI表现为病变椎间盘变薄或消失，呈混杂长T1，混杂长T2，信号，周围组织不同程度受累。②治疗组结果：急性期7例，保守治疗痊愈6例，手术治疗痊愈1例。慢性期3例，痊愈2例，1例遗留慢性腰痛症状。③对照组结果：急性期7例，保守治疗痊愈3例，手术治疗痊愈4例。慢性期3例，痊愈1例，无效2例（改用综合治疗方法后痊愈）。结论：MRI对感染性椎间盘炎的诊断及监测治疗效果有重要价值；对感染性椎间盘炎临床应根据分期采用综合治疗。     

Pathomechanics and clinical relevance of disc degeneration and annular tear: a point-of-view review.

Annular tear is a major cause of intervertebral disc degeneration that results in disabling back pain. Many of the stresses resulting in this type of lesion are common in the workplace: compression, torsion, compression combined with flexion, and vibration. Age-related disc degeneration begins early in adulthood, and progresses thereafter, altering disc morphology and mechanical properties in ways that predispose to disc herniation, and should not be misconstrued as "old age." Acute trauma may produce disc herniation whether or not there are predisposing factors, such as age-related degeneration, but disc herniation in the absence of acute injury requires the presence of preexisting degenerative changes.     

Mechanical initiation of intervertebral disc degeneration

STUDY DESIGN: Mechanical testing of cadaveric lumbar motion segments. OBJECTIVES: To test the hypothesis that minor damage to a vertebral body can lead to progressive disruption of the adjacent intervertebral disc. SUMMARY OF BACKGROUND DATA: Disc degeneration involves gross structural disruption as well as cell-mediated changes in matrix composition, but there is little evidence concerning which comes first. Comparatively minor damage to a vertebral body is known to decompress the adjacent discs, and this may adversely affect both structure and cell function in the disc. METHODS: In this study, 38 cadaveric lumbar motion segments (mean age, 51 years) were subjected to complex mechanical loading to simulate typical activities in vivo while the distribution of compressive stress in the disc matrix was measured using a pressure transducer mounted in a needle 1.3 mm in diameter. "Stress profiles" were repeated after a controlled compressive overload injury had reduced motion segment height by approximately 1%. Moderate repetitive loading, appropriate for the simulation of light manual labor, then was applied to the damaged specimens for approximately 4 hours, and stress profilometry was repeated a third time. Discs then were sectioned and photographed. RESULTS: Endplate damage reduced pressure in the adjacent nucleus pulposus by 25% +/- 27% and generated peaks of compressive stress in the anulus, usually posteriorly to the nucleus. Discs 50 to 70 years of age were affected the most. Repetitive loading further decompressed the nucleus and intensified stress concentrations in the anulus, especially in simulated lordotic postures. Sagittal plane sections of 15 of the discs showed an inwardly collapsing anulus in 9 discs, extreme outward bulging of the anulus in 11 discs, and complete radial fissures in 2 discs, 1 of which allowed posterior migration of nucleus pulposus. Comparisons with the results from tissue culture experiments indicated that the observed changes in matrix compressive stress would inhibit disc cell metabolism throughout the disc, and could lead to progressive deterioration of the matrix. CONCLUSIONS: Minor damage to a vertebral body endplate leads to progressive structural changes in the adjacent intervertebral discs.     

椎间盘退变病因学研究概况

椎间盘退变是腰背痛的主要原因之一,目前的治疗方法仍不理想,原因在于其病因机制尚未完全阐明.近年研究发现椎间盘退变由多种因素影响所致,椎间盘细胞能合成和分泌一些细胞因子,加重炎症反应并影响椎间盘的物质代谢,促进椎间盘退变;某些具有遗传特性的特异性基因与椎间盘退变相关;椎间盘渗透功能降低会引起椎间盘营养障碍,导致椎间盘退变.     

大鼠腰椎间盘退变模型的MRI及病理学观察

目的研究大鼠腰椎间盘退变模型的MRI表现及病理学改变。方法随机选取32只SD大鼠,分为实验组和对照组,每组各16只。实验组采用手术方法以L3为中心切除相关腰椎的棘突、关节突、棘上韧带棘间韧带,切断双侧竖棘肌。通过改变脊柱的生物力学制作腰椎问盘退变动物模型。对照组仅切开皮肤后即缝合。术后分别于1个月、2个月、3个月行MRI检查,之后处死行病理学观察。结果MRI检查结果对照组：无特异性改变,实验组：于术后2个月、3个月时的T2信号明显降低。病理学检查对照组：无明显变化,实验组：表现为髓核细胞减少,外周纤维环结构紊乱。结论本实验方法的建立为研究腰椎间盘退变提供了比较理想的动物模型。