Growth factors in intervertebral disc homeostasis

Intervertebral disc degeneration is a complex age-related pathology associated with back pain. Research on the growth factors that regulate disc homeostasis is of critical importance for understanding the basis of the disease. Here we summarize the data on the expression and function of various growth factors in the disc from in vivo and in vitro studies, as well as on their alterations during degeneration and ageing. Such studies are becoming more crucial in the prospect of clinical application of growth factors for the treatment of disc degeneration.     

Finite element application in implant research for treatment of lumbar degenerative disc disease

Surgical treatment for disc degeneration can be roughly grouped as fusion, disc replacement and dynamic stabilization. The clinical efficacy and biomechanical features of the implants used for disc degenerations can be evaluated through short- or long-term follow up observation, in vitro and in vivo experiments and computational simulations. Finite element models are already making an important contribution to our understanding of the spine and its components. Models are being used to reveal the biomechanical function of the spine and its behavior when healthy, diseased or damaged. They are also providing support in the design and application of spinal instrumentation. The article reviewed the most recent studies in the application of FE models that address the issue of implant research for treatment of low back pain. The published studies were grouped and reviewed thoroughly based on the function of implants investigated. The considerations of the finite element analysis in these studies were further discussed.     

Roles of large aggregating proteoglycans in human intervertebral disc degeneration

Degeneration of the intervertebral discs, a natural progression of the aging process, is strongly implicated as a cause of low back pain. Aggrecan is the major structural proteoglycan in the extracellular matrix of the intervertebral disc. It is large, possessing numerous glycosaminoglycan chains and the ability to form aggregates in association with hyaluronan. The negatively charged glycosaminoglycan side chains in aggrecan in the nucleus pulposus of the intervertebral discs can bind electrostatically to polar water molecules, which are crucial for maintaining the well-hydrated state that enables the discs to undergo reversible deformation under compressive loading. A more in-depth understanding of the molecular basis of disc degeneration is essential to the design of therapeutic solutions to treat degenerative discs. Within this scope, we discuss the current knowledge concerning the structure and function of aggrecan in intervertebral disc degeneration. These data suggest that aggrecan plays a central role in the function and degeneration of the intervertebral disc, which may suggest potential aggrecan-based therapies for disc regeneration.     

Link protein N-terminal peptide and fullerol promote matrix production and decrease degradation enzymes in rabbit annulus cells

Purpose: Intervertebral disc degeneration is a major cause of back pain. Novel therapies for prevention or reversal of disc degeneration are needed. It is desirable for potential therapies to target both inflammation and matrix degeneration. Materials and Methods: The combined regenerative potential of link protein N-terminal peptide (LN) and fullerol on annulus fibrosus (AF) cells was evaluated in a 3D culture model. Results: Interleukin-1α (IL-1α)-induced AF cell degeneration was counteracted by fullerol, LN, and fullerol + LN, with the latter having the greatest effect on matrix production as evaluated by real-time polymerase chain reaction and glycosaminoglycan assay. IL-1α-induced increases in pro-inflammatory mediators (interleukin-6 and cyclooxygenase-2) and matrix metalloproteinases (MMP-1, -2, -9, and -13) were also counteracted by fullerol and LN. Conclusion: Our data demonstrate that LN and fullerol individually, and in combination, promote matrix production and have anti-inflammatory and anti-catabolic effects on AF cells.     

The improvement of calvarial bone healing by durable nanogel-crosslinked materials

Abstract

Different approaches have been developed to improve the scaffold properties that provide structural support and biological interaction to achieve the desired environment for tissue regeneration. We previously reported that addition of human fibroblast growth factor 18 (hFGF18) to acryloyl group-modified cholesterol-bearing pullulan (CHPOA) nanogel-crosslinked (NanoClik) hydrogels that contain human bone morphogenetic protein 2 (hBMP2) stabilized bone healing in mouse calvarial defect model. In this study, we evaluated the use of disc-shaped dried nanogel-crosslinked gel as carriers of growth factors in order to seek possible clinical application in future. Both conventionally-dried NanoClik disc and nanogel-crosslinked porous (NanoCliP) disc made by freeze-drying that contained the growth factors induced bone healing but not as much as with NanoClik hydrogel application but addition of RGD peptides (RGD-NanoCliP disc) improved the healing. All type of discs showed the same biphasic ovalbumin-Alexa Fluor 488 protein release profile in vitro, an initial burst followed by a gradual sustained release more than one week, which was confirmed in vivo. Histological analysis showed remarkable new bone formation with more calcification in RGD-NanoCliP disc with the growth factors and the osteogenesis appeared to begin in the dura mater in contact with the disc. These observations suggest: (1) the fitness of the durable discs to the bone defect is a critical factor for bone healing, which is supplemented by addition of RGD peptides, (2) the porosity is suitable for osteoblast recruitment, (3) growth factor release pattern of the CHPOA nanogel based gels is ideal for bone healing.     

Damage to the human lumbar cartilage endplate and its clinical implications

The cartilaginous endplate (CEP) is a thin layer of hyaline cartilage, and plays an important role in the diffusion of nutrients into the intervertebral discs. Its damage may seriously affect the disc degeneration, and result in low back pain (LBP). However, the structural features of damaged CEPs have not been well characterized, and this hinders our understanding of the etiology of disc degeneration and pain. To present the structural features of micro-damaged CEPs in patients with disc degeneration and LBP that might even be regarded as an initial factor for disc degeneration, we performed a histological study of micro-damaged CEPs harvested from human lumbar intervertebral discs and analyzed its clinical implications. Human lumbar CEPs were excised from 35 patients (mean age 60.91 years) who had disc degeneration and LBP. Control tissue was obtained from 15 patients (mean age 54.67 years) with lumbar vertebral burst fractures. LBP and disability were assessed clinically, and all patients underwent anterior vertebral body fusion surgery. CEPs together with some adjacent nucleus pulposus (NP) were sectioned at 4 µm, and stained using H&E, Safranin O/Fast Green, and Alcian Blue. Immunostaining and PCR were used to identify various markers of degeneration, innervation, and inflammation. Histology demonstrated physical micro-damage in 14/35 CEPs from the disc degeneration group. Six major types of damage could be distinguished: fissure, traumatic nodes, vascular mimicry, incorporation of NP tissue within the CEP, incorporation of bone within the CEP, and incorporation of NP and bone within the CEP. Pain and disability scores (ODI: p = 0.0190; JOA: p = 0.0205; JOABPEQ: p = 0.0034) were significantly higher in those with micro-damaged CEPs (N = 14) than in those with non-damaged CEPs (N = 21). CEP damage was significantly associated with elevated MMP3 (p = 0.043), MMP13 (p = 0.0191), ADAMTS5 (p = 0.0253), TNF-α (p = 0.0011), and Substance P (p = 0.0028), and with reduced Sox9 (p = 0.0212), aggrecan (p = 0.0127), and type II collagen (p = 0.0139). In conclusion, we presented a new classification of human lumbar micro-damaged CEPs. Furthermore, we verify disc degeneration, innervation, and discogenic pain in micro-damaged CEPs.     

椎间盘退行性变的相关生物分子因素

背景：随着年龄的增长,椎体过度活动和超负荷承载使椎体加快出现老化,并在外力的作用下,继发病理性改变,以致椎间盘纤维环破裂,椎间盘内的髓核突出,引起腰腿痛和神经功能障碍。 目的：总结椎间盘退行性变的相关生物分子因素的研究进展,并展望其发展趋势。 方法：应用计算机检索PubMed数据库;中国知网数据库;万方数据库;维普数据库2000-02/2012-01有关椎间盘退行性变的相关生物分子因素的文献。检索文献包括研究原著及综述,排除重复性研究。 结果与结论：共保留32篇文献归纳总结。椎间盘退变是由多种相关因素在长期条件下相互作用而引起的,是一系列脊柱退行性病变的前提和慢性病理过程的基础。椎间盘髓核细胞不仅是残留脊索细胞,而且对于整个椎间盘功能的维持起到重要作用。对髓核细胞在RNA、DNA及蛋白水平相关生物分子因素的研究,为延缓及治疗以及将来扭转和修复椎间盘退行性变提供了可能。     

生长因子治疗椎间盘退变的研究进展

目的：探讨椎间盘退变的发生机制,总结生长因子治疗椎间盘退变的相关研究成果,并提出尚待解决的问题和未来研究的热点。方法：从刺激椎间盘细胞增殖,促进椎间盘基质的合成,抑制椎间盘细胞的凋亡,应用方式,现阶段研究中存在的问题等方面对国内外相关研究进行总结。结果：使用生长因子治疗椎间盘退变可以从生理结构上阻止、逆转椎间盘退变,恢复椎间盘丢失的高度和生物学功能。结论：椎间盘的生长因子治疗尚存在一定的问题和不足,随着研究的深入和应用方法的改进,生长因子治疗有望为椎间盘退变提供一条新的治疗途径。     

腰椎间盘退变的分子病理学变化及发病机制

背景：腰椎间盘退变是引起腰腿痛的常见原因,椎间盘退变的病理改变及发病机制至今仍未完全明确。 目的：介绍腰椎间盘退变的分子病理改变及其发病机制的研究进展。 方法：以“disc histology,disc degenerative disease,disc gene”等主题词检索PubMed数据库,检索时间为2005/2010年,筛选与腰椎间盘组织学变化和发病机制相关的文献,总结归纳腰椎间盘退变的研究进展和研究结果。 结果与结论：共检索到与腰椎间盘退变有关的文章118篇,共纳入30篇。结果表明腰椎间盘退变受多种因素影响,包括基因遗传因素、自然老化和积累性损伤等,基因的多形性是诱发退变的重要前置因素。椎间盘退变可通过免疫反应、机械性压迫或不稳定、血循环障碍和炎性递质等因素导致椎间盘退变性疾病。老化和病理性退变在影像和病理上难以区别,应根据椎间盘退变性疾病的具体情况采取合理的治疗方法,生物学治疗提供了新的治疗思路,但目前仍处在实验研究阶段。     

脊柱椎间盘退变与高尿酸血症的相关性

背景:高尿酸血症是常见的代谢性疾病,高尿酸血症患者以尿酸结晶形成导致痛风为主要临床表现。既往研究仅报道了尿酸结晶会导致脊柱椎间盘的退变,但关于高尿酸血症与脊柱椎间盘退变的相关性研究较少。目的:回顾性分析高尿酸血症患者脊柱椎间盘的退变特点以及血尿酸浓度与脊柱椎间盘退变的相关性。方法:回顾性分析2021年1月至2022年12月在西南医科大学附属医院骨科就诊并被诊断为脊柱椎间盘退变的所有患者,纳入97例高尿酸血症患者作为高尿酸血症组,然后根据性别、年龄按照1∶2进行匹配,将194例非高尿酸血症患者作为对照组。收集两组患者的血尿酸检验结果,并在全脊柱MRI图像上对两组患者的椎间盘退变程度进行Pfirrmann评分。比较两组患者椎间盘退变程度的差异,分析血尿酸浓度与椎间盘退变程度的相关性。结果与结论:①高尿酸血症组的椎间盘退变程度Pfirrmann评分大于对照组,且高尿酸血症组的椎间盘退变总数大于对照组,差异均有显著性意义(P<0.05);②Spearman相关分析显示,在高尿酸血症组内的多个节段,男性患者的椎间盘退变程度与血尿酸浓度呈正相关(C_(3/4):r=0.317,C_(4/5):r=0.333,C_(5/6):r=0.309,L_(2/3):r=0.443;P<0.05);女性患者的椎间盘退变程度也与血尿酸浓度呈正相关(C_(3/4):r=0.354,C_(4/5):r=0.388,C_(6/7):r=0.312,T_(7/8):r=0.282,T_(9/10):r=0.305,T_(11/12):r=0.277,L_(4/5):r=0.319,L_(5)-S_(1):r=0.367,P<0.05);③在对照组中,男性和女性患者的椎间盘退变程度与血尿酸浓度无明显相关性(P>0.05);④结果提示:在高尿酸血症患者中,血尿酸浓度越高,椎间盘退变程度越严重。因此,高尿酸血症是导致椎间盘退变的危险因素之一。     

Release of active and depot GDF-5 after adenovirus-mediated overexpression stimulates rabbit and human intervertebral disc cells

To develop new therapeutic options for the treatment of disc degeneration we tested the possibility of overexpression of active growth and differentiation factor (GDF) 5 and of transforming growth factor (TGF) ₁ by adenoviral gene transfer and characterized its effect on cell proliferation and matrix synthesis of cultured rabbit and human intervertebral disc cells. Recombinant adenovirus encoding for GDF-5 or TGF-₁ was developed and transgene expression characterized by RT-PCR, western blot and ELISA. Growth and matrix synthesis of transduced cells was measured by [³H]thymidine or [³⁵S]sulfate incorporation. Disc cells expressed the receptors BMPR1A, BMPR1B, and BMPR2, which are relevant for GDF-5 action. Adenovirus efficiently transferred the GDF-5 gene or the TGF-₁ gene to rabbit and human intervertebral disc cells. About 50 ng GDF-5 protein/10⁶ cells per 24 h or 7 ng TGF-₁ protein/10⁶ cells per 24 h was produced. According to western blotting, two GDF-5 forms, with molecular weights consistent with the activated GDF-5 dimer and the proform, were secreted over the 3 weeks following gene transfer. Overexpressed GDF-5 and TGF-₁ were bioactive and promoted growth of rabbit disc cells in monolayer culture. Our results suggest that ex vivo gene delivery of GDF-5 and TGF-₁ is an attractive approach for the release of mature and pre-GDF-5 in surrounding tissue. This leads us to hope that it will prove possible to improve the treatment of degenerative disc disease by means of ex vivo gene transfer of single or multiple growth factors.Abbreviations BMP Bone morphogenetic proteins - CHO Chinese hamster ovary - ELISA Enzyme-linked immunosorbent assay - FCS Fetal calf serum - GDF Growth and differentiation factor - GFP Green fluorescent protein - IVD Intervertebral discs - MOI Multiplicity of infection - TGF Transforming growth factor     

Intervertebral disc regeneration in an ex vivo culture system using mesenchymal stem cells and platelet-rich plasma

An ex vivo degenerative intervertebral disc (IVD) organ culture system was established for the screening of disc regeneration agents. Its application was demonstrated by a stem cell and growth factor-based therapeutic approach for the amelioration of IVD. An ex vivo culture system using chymopapain to partially digest nucleus proposus tissue was established to mimic human IVD degeneration. This system was then used for the evaluation of different therapeutic regimens including: mesenchymal stem cell derived from eGFP-transgenic porcine (MSC-GFP), platelet-rich plasma (PRP) and MSC-GFP/PRP combined treatment, and confirmed in in vivo animal model. Chondrogenic-specific gene products including Col II and aggrecan were found upregulated and chondrogenic matrix deposition increased, as evident by sustained fluorescent signals over 4 weeks, in the MSC-GFP implanted group. Previously, we demonstrated in vitro stage-specific chondrogenesis of MSC by chondrocytic commitment. These same molecules upregulated for chondrogenesis were also observed in MSC-GFP group. PRP that has been shown to promote nucleus pulposus (NP) regeneration also resulted in significant increased levels of mRNA involved in chondrogenesis and matrices accumulation. The ex vivo IVD regeneration results were repeated and supported by in vivo porcine degenerative system. Moreover, the disc height index (DHI) was significantly increased in both in vivo MSC-GFP and PRP regeneration groups. Unexpectedly, the MSC-GFP/PRP combined therapy demonstrated an inclination towards osteogenesis in ex vivo system. The ex vivo degenerative IVD culture system described in this study could serve as an alternative and more accessible model over large animal model. This system also provides a high-throughput platform for screening therapeutic agents for IVD regeneration.     

Assessment of glycosaminoglycan distribution in human lumbar intervertebral discs using chemical exchange saturation transfer at 3 T: feasibility and initial experience

Recent studies have proposed that glycosaminoglycan chemical exchange saturation transfer (gagCEST) is associated with a loss of glycosaminoglycans (GAGs), which may be an initiating factor in intervertebral disc (IVD) degeneration. Despite its promising potential, this application has not been reported in human in vivo IVD studies because of the challenges of B₀ magnetic field inhomogeneity in gagCEST. This study aimed to evaluate the feasibility of quantifying CEST values in IVDs of healthy volunteers using a clinical 3 T scanner. A single‐slice turbo spin echo sequence was used to quantify the CEST effect in various GAG phantoms and in IVDs of 12 volunteers. The phantom results indicated high correlation between gagCEST and GAG concentrations (R² = 0.95). With optimal B₀ inhomogeneity correction, in vivo CEST maps of IVDs showed robust contrast between the nucleus pulposus (NP) and the annulus fibrosus (AF) (p < 0.01), as well as higher signal in the central relative to the peripheral NP. In addition, a trend of decreasing CEST values from upper to lower disc levels was evident in NP. Our results demonstrate that in vivo gagCEST quantification in human lumbar IVDs is feasible at 3 T in combination with successful B₀ inhomogeneity correction, but without significant hardware modifications. Our initial findings suggest that it would be worthwhile to perform direct correlation studies between CEST and GAGs using cadaver samples, and to extend this novel technique to studies on patients with degenerative discs to better understand its distinct imaging features relative to conventional techniques. Copyright © 2011 John Wiley & Sons, Ltd.     

退行性变椎间盘组织转化生长因子β1基因的表达

背景：据报道,转化生长因子β1能促进椎间盘细胞的增殖与分化,并参与其损伤修复过程。但转化生长因子β1是否参与椎间盘退变的过程？ 目的：分析在人体退行性变椎间盘组织中转化生长因子β1的表达情况,并探讨其与人体椎间盘退行性变的关系。 方法：收集正常椎间盘组织30例,退行性变人体椎间盘组织530例,采用苏木精-伊红染色、免疫印迹和RT-PCR方法进行研究,对退行性变的椎间盘组织进行病理学分型,分别检测转化生长因子β1在不同类型退变的椎间盘中表达的情况并与正常椎间盘组织进行对比分析。 结果与结论：苏木精-伊红染色病理学诊断：将退行性变的椎间盘组织根据病理学改变程度分为4型。免疫印迹法和RT-PCR法均显示：在正常和退变椎间盘组织中,转化生长因子β1均有表达,但在病变组织中随病变加重转化生长因子β1表达量随之增加,退变组织与正常组织比较差异有非常显著性意义 (P < 0.01)。说明转化生长因子β1高表达与人体椎间盘退行性变呈正相关。     

Effect of Severity of Intervertebral Disc Injury on Mesenchymal Stem Cell-Based Regeneration

Mesenchymal stem cell (MSC) implantation has been shown previously to arrest disc degeneration. This study aims to assess the effect of severity of disc degeneration on the ability of MSCs to arrest the degeneration. Disc degeneration was induced in New Zealand white rabbits at lumbar levels by annular puncture. The degeneration was allowed to progress for 1 month (early group) or 7 months (late group), followed by intradiscal injection of autologous MSCs. For disc levels that received MSCs treatment, 1 × 10⁵ BrdU-labeled MSCs were injected per disc level. For the early group, MSC-injection had no significant effects on disc height or the progression of disc degeneration. For the late group, although the MSC-injected discs displayed lower disc heights than the control discs, they were significantly less degenerated together with near normal level of proteoglycan in localized areas. This is the first pilot study to demonstrate that severity of degeneration can influence the therapeutic effect of MSCs. Future studies of cell-based intervertebral disc regeneration should be carefully controlled in the context of stage of disc degeneration.     

椎间盘退变模型的研究现状及进展

目的：探讨椎间盘退变模型的研究现状及进展。方法：在Pubmed、中国知网查阅有关椎间盘退变模型研究的文献,进行汇总分析。结果：椎间盘退变模型可以通过体外和体内两种方法构建,前者包括椎间盘细胞模型和椎间盘组织模型,后者包括诱发性椎间盘退变模型和自发性椎间盘退变模型。体外模型适用面较广,但培养要求较高,不能全面模拟体内环境;体内培养干预技术较容易实现,但适用面较窄。结论：人椎间盘退变的影响因素繁多,目前的椎间盘退变模型往往具有一定的局限性,无法全面地模拟出人的椎间盘退变情况。无创、微创构建椎间盘退变模型将是未来的发展趋势。     

Glucosamine and chondroitin sulfate supplementation to treat symptomatic disc degeneration: Biochemical rationale and case report

Background

Glucosamine and chondroitin sulfate preparations are widely used as food supplements against osteoarthritis, but critics are skeptical about their efficacy, because of the lack of convincing clinical trials and a reasonable scientific rationale for the use of these nutraceuticals. Most trials were on osteoarthritis of the knee, while virtually no documentation exists on spinal disc degeneration. The purpose of this article is to highlight the potential of these food additives against cartilage degeneration in general, and against symptomatic spinal disc degeneration in particular, as is illustrated by a case report. The water content of the intervertebral disc is a reliable measure of its degeneration/ regeneration status, and can be objectively determined by Magnetic Resonance Imaging (MRI) signals.

Case presentation

Oral intake of glucosamine and chondroitin sulfate for two years associated with disk recovery (brightening of MRI signal) in a case of symptomatic spinal disc degeneration. We provide a biochemical explanation for the possible efficacy of these nutraceuticals. They are bioavailable to cartilage chondrocytes, may stimulate the biosynthesis and inhibit the breakdown of their extracellular matrix proteoglycans.

Conclusion

The case suggests that long-term glucosamine and chondroitin sulfate intake may counteract symptomatic spinal disc degeneration, particularly at an early stage. However, definite proof requires well-conducted clinical trials with these food supplements, in which disc de-/regeneration can be objectively determined by MRI. A number of biochemical reasons (that mechanistically need to be further resolved) explain why these agents may have cartilage structure- and symptom-modifying effects, suggesting their therapeutic efficacy against osteoarthritis in general.

     

Mechanisms of Mineralization in the Enameloid of Elasmobranchs and Teleosts

Ultrastructural and cytochemical studies on the mineralization of enameloid were performed using Heterodontus japonicus, an elasmobranch, and Tilapia buttikoferi, a teleost as materials. The mineralization of the enameloid in the Heterodontus was divided into the following two steps: (1) initial crystallization in the tubular vesicles that originated from the odontoblasts, and (2) crystal growth that was accompanied by the degeneration and removal of the organic matrix around the crystals. In the Tilapia, the mineralization of the cap enameloid followed three steps: (1) initial crystallization at the matrix vesicles, (2) aggregation of fine slender crystals along collagen fibrils, and (3) crystal growth with the degeneration and removal of the organic matrix. The pattern of early mineralization and the composition of organic matrix in enameloid were considerably different between the two species examined, while in both species the odontoblasts were mainly involved in the formation of the organic matrix of enameloid and in the initial mineralization. In the next step, remarkable crystal growth associated with the degeneration and removal of the organic matrix occurred in both the elasmobranch and the teleost species. The absorptive functions of the dental epithelial cells in the later stages of enameloid formation is probably similar in the two types of enameloid, and is essential for the production of well-mineralized enameloid.     

The interaction between aggrecan gene VNTR polymorphism and cigarette smoking in predicting incident symptomatic intervertebral disc degeneration

An association between the aggrecan variable number of tandem repeat (VNTR) polymorphism and the disc degeneration has been previously reported in Finnish men, and smoking had previously been suspected of causing disc degeneration. However, the interaction between aggrecan gene VNTR polymorphism and smoking in symptomatic intervertebral disc degeneration (IDD) has not been well studied. To examine the interaction between aggrecan gene VNTR and smoking in the susceptibility of symptomatic IDD of Chinese Han in northern China, intervertebral discs of 132 participants were evaluated on magnetic resonance imaging, using decreased signal intensity. After harvesting the blood samples, the aggrecan gene VNTR region was analyzed using polymerase chain reaction (PCR). The data indicated that between the two groups, participants carrying one or two alleles ≤25 repeats who did not smoke showed a 1.102-fold increased risk for symptomatic IDD (p= 0.855; 95% confidence interval 0.389–3.119), and participants carrying two alleles >25 repeats who smoked more than 1 pack-year showed a 1.013-fold higher risk (p = 0.982; 95% confidence interval 0.333–3.084), whereas participants carrying one or two alleles ≤25 repeats who smoked more than 1 pack-year showed a 4.5-fold increased risk for symptomatic IDD (p = 0.005; 95% confidence interval 1.589–12.743). Overall, we observed an underlying additive and multiplicative interaction between the aggrecan gene VNTR polymorphism and smoking in symptomatic IDD.     

软骨终板形态与椎间盘退变的相关性

背景：以往研究证明多种内环境因素共同作用引发椎间盘退变,最重要的机制为椎间盘软骨终板的退变。 目的：分析椎间盘退变与终板形态的关系。 方法：回顾性分析62例因椎间盘源性慢性下腰痛和79例因髓核脱出致神经根性症状患者的腰椎MRI正中矢状位图像资料。根据腰椎MRI正中矢状位T1W1图像确定终板形态,T2W1图像确定椎间盘退变程度分级。 结果与结论：平坦型和不规则型终板最常见于椎间盘退变人群下腰椎,L5/S1平坦型最多见。髓核脱出组与椎间盘源性慢性下腰痛组中凹陷型终板椎间盘退变程度均较平坦型、不规则型低,平坦型终板椎间盘退变程度较不规则型低(P < 0.01)。两组间凹陷型与不规则型终板椎间盘退变程度差异无显著性意义,髓核脱出组平坦型椎间盘退变程度较椎间盘源性慢性下腰痛组高(P < 0.05)。提示随着椎间盘退变程度的加重,软骨终板形态有由凹陷型向平坦型、不规则型依次转变的趋势。