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Radiological features of traumatic vertebral endplate fracture:an analysis of 194 cases with 263 vertebral fractures

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Chinese Medical Journal 2020年第22期133卷 2696-2702页

作者： Xiao-Rong Wang Fei-Rong Xu Qiu-Li Huang Yi Xiang J.Wang Department of Radiology Ningbo First HospitalNingboZhejiang 315010China Department of Imaging and Interventional Radiology Faculty of MedicinePrince of Wales HospitalThe Chinese University of Hong KongHong KongChina Department of Radiology Ningbo Women and Children's HospitalNingboZhejiang 315012China

Background:The importance of identifying osteoporotic vertebral endplate or/and cortex fracture(ECF),which primarily includes endplate fracture(EPF)and vertebral anterior cortex buckling,has been recognized.However,some old traumatic ECFs with healing process in the elderly may be mistaken as osteoporotic.This study analyzes the radiological features of traumatic EPF.Methods:This was a retrospective analysis of 194 spine trauma patients with 263 vertebral fractures(mean age:42.11±9.82 years,118 males and 76 females).All patients had traumatic EPF identified by X-ray/CT/MRI.Results:The involved vertebra was mostly L1(29.7%),followed by T12 and L2.Except EPFs involved both superior and inferior endplates(12.6%),only 1.9%involved inferior endplate alone,with the majority involved superior endplate.If each endplate was divided into five segments of equal lengths(from anterior to posterior:a1,a2,m,p2,p1),the most depressed point of superior EPFs was mostly at segment-a2(approximately 45%),followed by segment-a1(approximately 20%)or segment-m(approximately 20%),and very rarely at segment-p1.The upper 1/3 of anterior vertebral wall was more likely to fracture,followed by middle 1/3 of anterior wall.For posterior vertebral wall fracture,68.5%broke the bony wall surrounding the basivertebral vain.58.6%,30.0%,and 11.4%of vertebral fractures had1/3 vertebral body height loss.As the extent of vertebral height loss increased,the chance of having both superior and inferior EPFs also increased;however,the chance of having inferior EPF alone did not increase.Conclusion:Traumatic EPF features are characterized,which may help the differentiation of traumatic and osteoporotic EPFs.

关键词： Spine Vertebral fracture endplate Traumatic Vertebral cortex

Effect of osteoporosis and intervertebral disc degeneration on endplate cartilage injury in rats

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Asian Pacific Journal of Tropical Medicine 2014年第10期7卷 796-800页

作者： Lei Wang Wei Cui Jean Pierre Kalal Tom Van Hoof Bao-Ge Liu Department of Orthopaedics Beijing Tiantan Hospital affiliated to Capital Medical University Department of Neurosurgery University HospitalUniversity of GhentBelgium Department of Human Anatomy EmbryologyHistology and Medical PhysicsUniversity of GhentBelgium

Objective:To investigate the effect of osteoporosis and intervertebral disc degeneration on the endplate cartilage injury in rats.Methods:A total of 48 female Sprague Dawley rats(3 months)were randomly divided into Groups A,B,C and D with 12 rats in each group.Osteoporosis and intervertebral disc degeneration composite model,simple degeneration model and simple osteoporosis model were prepared in Groups A,B and C respectively.After modeling,four rats of each group at 12th.18th and 24th week were sacrificed,Intervertebral height of cervical vertebra C6/C7 was measured.Micro-CT was used to image the endplate of cephalic and caudal cartilage at C6/C7 intervertebral disc.Abraded area rate of C6 caudal and C7 cephalic cartilage endplate was calculated,and then C6/C7 intervertebral disc was routinely embedded and sectioned.stained with safranin O to observe histological changes microscopically.Results:At 12,18 and24 weeks,intervertebral disc height of C6/C7 were(0.58±0.09)mm,(0.53±0.04)mm and(0.04±0.06)mm in Group A rats,(0.55±0.05)mm,(0.52±0.07)mm and(0.07±0.05)mm in Group B rats.At 24th week.intervertebral disc height of Group A rats was significantly lower than that of Group B rats(P0.05).At 12 and 18 weeks,the abraded rate of C6 caudal and C7 cephalic cartilage endplate in Group A rats were significantly higher than that in Groups B.C and D rats(P0.05).Microscopic observation of CT showed that ventral defects in C6caudal or C7 cephalic cartilage endplate in Groups A and B appeared after 12 weeks of modeling;obvious cracks were found in front of the C6 and C7 vertebral body,and cartilage defect shown the trend of"repairing"at 18 and 24 weeks after modeling.Conclusions:Intervertebral disc de

关键词： Osteoporosis Intervertebral disc degeneration Vertebral bodies Cartilage endplate Damage

Effects of Muscle Electrical Activity on the Transmission of Developing Neuromuscular Junction

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Science China Chemistry 1994年第5期37卷 573-580页

作者：汤云贵谢佐平毛健何展全赵南明 State Key Laboratory of Biomembrane and Membrane Biotechnique Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 PRC

Miniature endplate potentials (MEPPS) caused by the spontaneous release of ACh from the growth cone of cholinergic neurons, are recorded by the whole-cell patch-clamp technique on a large number of 1-day cultured myoballs which have contact neurites of co-cultured neurons. Both muscle cell and neuron are dissociated from the 1-day-old (about stage 20) Xenopus embryo. Frequency and/or amplitude of MEPPs can obviously increase after the repetitive high-level depolarization caused by the stimuli on muscle cells. No detectable changes of single ACh receptor channel property are observed by using the single-channel recording technique. These results suggest that the mechanism of the increase of MEPPs after electrical activity of postsynaptic muscle cells probably involve some alteration of presynaptic membrane.

关键词： electrical activity of muscle cell patch-clamp technique miniature endplate potentials (MEPPs) acetylcholine (ACh) receptor channel.

Biomechanical effects of bone cement volume on the endplates of augmented vertebral body： a three-dimensional finite element analysis

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Chinese Medical Journal 2014年第1期127卷 79-84页

作者： Yan Liang Chang Zhen Xu Zhengwei Liu Tuanjiang He Baorong Hao Dingjun Department of Spine Surgery Hong Hui Hospital Xi'an Jiaotong University College of Medicine Xi'an Shaanxi 710054 China Department of Spine Surgery Shaanxi Province Orthopaedic Hospital Xi'an Shaanxi 710054 China

Background Previous studies have suggested that percutaneous vertebroplasty might alter vertebral stress transfer,leading to adjacent vertebral failure.However,no three-dimensional finite element study so far accounted for the stress distributions on different cement volumes.The purpose of this study was to evaluate the stress distributions on the endplate under different loading conditions after augmentation with various volumes of bone cement.Methods L2-L3 motion segment data were obtained from CT scans of the lumbar spine from a cadaver of a young man who had no abnormal findings on roentgenograms.Three-dimensional model of L2-L3 was established using Mimics software,and finite element model of L2-L3 functional spinal unit （FSU） was established using Ansys10.0 software.For simulating percutaneous vertebral augmentation,polymethylmethacrylate （PMMA） was deposited into the bipedicle of the L2 vertebra.The percentage of PMMA volume varied between 15％ and 30％.The stress distributions on the endplate of the augmented vertebral body were calculated under three different loading conditions.Results In general,the stress level monotonically increased with bone cement volume.Under each loading condition,the stress change on the L2 superior and inferior endplates in three kinds of finite element models shows monotonic increase.Compared with the stress-increasing region of the endplate,the central part of the L2 endplate was subject to the greatest stress under three kinds of loading conditions,especially on the superior endplate and under flexion.Conclusions The finite element models of FSU are useful to optimize the planning for vertebroplasty.The bone cement volume might have an influence on the endplate of the augmentation,especially the superior endplate.It should be noted that the optimization of bone cement volume is patient specific; the volume of the bone cement should be based on the size,body mineral density,and stiffness of the vertebrae of individual patients.

关键词： osteoporosis fracture finite element analysis vertebroplasty endplate stress distribution

Numerical Study on Air Turbines with Enhanced Techniques for OWC Wave Energy Conversion

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China Ocean Engineering 2017年第5期31卷 517-527页

作者： CUI Ying HYUN Beom-Soo KIM Kilwon Department of Ocean Engineering College of EngineeringOcean University of China Division of Naval Architecture and Ocean Engineering Korea Maritime and Ocean University

In recent years,the oscillating water column(OWC) wave energy converter,which can capture wave energy from the ocean,has been widely applied all over the world.As the essential part of the OWC system,the impulse and Wells turbines are capable of converting the low pressure pneumatic energy into the mechanical shaft power.As an enhanced technique,the design of endplate or ring attached to the blade tip is investigated numerically in this paper.3 D numerical models based on a CFD-software FLUENT 12.0 are established and validated by the corresponding experimental results from the reports of Setoguchi et al.(2004) and Takao et al.(2001).Then the flow fields and non-dimensional evaluating coefficients are calculated and analyzed under steady conditions.Results show that the efficiency of impulse turbine with ring can reach up to 0.49 when Ф=1,which is 4% higher than that in the cases for the endplate-type and the original one.And the ring-type Wells turbine with fixed guide vanes shows the best performance with the maximal efficiency of 0.55,which is 22% higher than that of the original one.In addition,the quasi-steady analysis is used to calculate the mean efficiency and output-work of a wave cycle under sinusoidal flow condition.Taking all together,this study provides support for structural optimization of impulse turbine and Wells turbine in the future.

关键词： OWC impulse turbine Wells turbine CFD endplate ring quasi-steady analysis

Pathophysiology, diagnosis, and treatment of discogenic low back pain

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World Journal of Orthopedics 2013年第2期4卷 42-52页

作者： Bao-Gan Peng Department of Spinal Surgery Institute of Spinal Surgery of Armed Police Force General Hospital of Armed Police Force

Discogenic low back pain is a serious medical and social problem, and accounts for 26%-42% of the patients with chronic low back pain. Recent studies found that the pathologic features of discs obtained from the patients with discogenic low back pain were the formation of the zones of vascularized granulation tissue, with extensive innervation in fissures extending from the outer part of the annulus into the nucleus pulposus. Studies suggested that the degeneration of the painful disc might originate from the injury and subsequent repair of annulus fibrosus. Growth factors such as basic fibroblast growth factor, transforming growth factor β1, and connective tissue growth factor, macrophages and mast cells might play a key role in the repair of the injured annulus fibrosus and subsequent disc degeneration. Although there exist controversies about the role of discography as a diagnostic test, provocation discography still is the only available means by which to identify a painful disc. A recent study has classified discogenic low back pain into two types that were annular disruption-induced low back pain and internal endplate disruption-induced low back pain, which have been fully supported by clinical and theoretical bases. Current treatment options for discogenic back pain range from medicinal anti-inflammation strategy to invasive procedures including spine fusion and recently spinal arthroplasty. However, these treatments are limited to relieving symptoms, with no attempt to restore the disc's structure. Recently, there has been a growing interest in developing strategies that aim to repair or regenerate the degenerated disc biologically.

关键词： Intervertebral disc Degeneration Diagnosis Treatment Discogenic low back pain Classification Internal disc disruption Internal annular disruption Internal endplate disruption

Rabbit models of Modic changes(MCs) is difficult to establish due to specific histological features of the endplate

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Rabbit models of Modic changes(MCs) is difficult to establis...

Quantitative Measures of Modic Changes in Lumbar Spine Magnetic Resonance Imaging

2016年浙江省骨科学学术年会

作者： Liu Junhui Zhao Fengdong Department of Othopaedics Sir Run Run Shaw HospitalSchool of MedicineZhejiang University

Objective:To establish a rabbit model of MCs and analyze why the rabbit model is difficult to generate from the point of view of histological endplate features.Methods:Thirty-six New Zealand White rabbits were randomly divided into 3 groups:the subchondral bone superior to discs of L4-5 and L5-6 were injected with 1 mL Propionibacteriumacne,normal saline(Vehicle),or punctured without injection(Sham) percutaneously.The degenerative process was evaluated using MRI before surgery,and 2 weeks,1,2,3,6 months postoperatively.Following sacrifice,TNF-α,IL-1β,IL-4,IFN-γ,PDGF-βexpression was quantified in endplate tissues.Histological features of the endplate were analyzed and compared with those of the adult mice,rats,monkeys and humans.Results:At 6 postoperative months,though TNF-a,IL-1β and IFN-γ levels in the P.acne,vehicle and sham group significantly increased compared to the blank control;only 6 of the 24 segments injected with P.acne were identified as type II MCs.The histological endplate structure varied significantly between animals and those of human.Rabbits and rats,in particular,contain a robust bony endplate with multiple vascular channels,which are absent in humans.The mouse endplate consists of primarily cartilage,and it is separated from the vertebral body by a layer of growth plate.The monkey and human endplate consists of a cartilaginous layer and the bony endplate without the growth plate.Conclusions:A rabbit model of MCs is hard to generate,given the special histological features of endplates,especially the robust bony endplate with multiple vascular channels.Monkey may be best choice for animal model of MCs.

关键词： Animal model Modic changes New Zealand White rabbit endplate

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Quantitative Measures of Modic Changes in Lumbar Spine Magne...