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Total lumbar disc replacement is an alternative to interbody fusion for the effective treatment of symptomatic degenerative disc disease. This paper reviewed the history of ball-on-socket type artificial lumbar disc (ALD) prosthesis, which is a typical ALD prosthesis and summarized the ALD prosthesis research progress, according to different materials such as metal-on-metal, metal-on-polymer, and polymer-on-polymer prosthesis. The structural design factors of ball-on-socket type ALD prosthesis were analyzed and its prospect of development was also presented. The purpose of this paper is to provide a theoretical reference for the design of the ball-on-socket ALD prosthesis by reviewing the current state of ball-on-socket type ALD prosthesis.
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In recent years, with the growth of social development, the incidence of lumbar vertebrae diseases has increased year by year, and many surgical methods have been developed. These treatment methods mark the accumulation of surgical experience and the development of medical technology. However, a new issue appears, i.e. how to evaluate the degree of lumbar disease and postoperative rehabilitation. There is an urgent need to establish a quantitative index of preoperative examination and postoperative rehabilitation criteria for lumbar disease from both doctors’ and patients’ perspectives. The current studies show that the measurement of the center of rotation (COR) for lumbar vertebrae and surface electromyography (sEMG) can reduce the error in the evaluation of clinical curative effect for treating lumbar disease and can be applied widely. This review summarizes the relationship between COR and lumbar disease, as well as the role of COR and sEMG joint evaluation in clinical operation and postoperative rehabilitation.
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Objective To establish a refined model of trunk composed of different lumbar segments, lumped thoracic spine and pelvis, analyze the kinematic differences between patients with lumbar disc herniation (LDH) and healthy people during three daily activities, and to compare the refined trunk model with the simplified trunk model adopting the whole lumbar segment, and discuss the necessity of using the refined trunk model for kinematic analysis of LDH patients. Methods Motion capture system NDI was used to collect kinematic parameters of each segment from 15 healthy people and 7 male LDH patients during level walking, trunk flexion and contralateral pickup, then the kinematic differences between patients and healthy people by the two models were compared respectively. Results During level walking, the rotation of the thoracic segment and pelvis for LDH patients increased, while no significant change was found in motion angle of the whole lumbar segment, and the rotation angle of L4-5 segment significantly reduced. During trunk flexion, the flexion angles of all lumbar segments for LDH patients were reduced by varying degrees, and the flexion angle of L3-4 segment was significantly different from that of healthy people. During contralateral pickup, the performance on the sagittal plane was similar to that during flexion. However, the lateral bending angles of L3-4 segment and L4-5 segment for LDH patients were significantly lower than those for healthy people. ConclusionsLDH patients mainly restrict the motion of injured lumbar segments in daily activities. During some motions, only refined model can discover the abnormal motion of injured lumbar segments. Therefore, it is necessary to subdivide the lumbar spine into 5 independent segments for analyzing the kinematic characteristics of LDH patients.
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Objective To study the biomechanical properties of porous titanium cages used for different lumbar interbody fusion surgeries. Methods The three-dimensional (3D) finite element model of the lumbar spine was constructed, and mechanical parameters of porous materials were obtained by mechanical test. The biomechanical properties of porous titanium cages in anterior lumbar interbody fusion (ALIF), posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), direct lateral interbody fusion (DLIF) were compared. Results After lumbar interbody surgery, the predicted range of motion (ROM) and the maximum stress in cage of DLIF model and ALIF model were substantially lower than those of PLIF model and TLIF model. The maximum stress in endplate of DLIF model, ALIF model and TLIF model were obviously lower than that of PLIF model. Conclusions DLIF with the porous cage showed advantages in biomechanical properties, which was simple to operate and suitable for minimally invasive surgery in clinical practice. DLIF performed the superior comprehensive properties.
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The mechanical properties of artificial intervertebral disc (AID) are related to long-term reliability of prosthesis. There are three testing methods involved in the mechanical performance evaluation of AID based on different tools: the testing method using mechanical simulator, specimen testing method and finite element analysis method. In this study, the testing standard, testing equipment and materials of AID were firstly introduced. Then, the present status of AID static mechanical properties test (static axial compression, static axial compression-shear), dynamic mechanical properties test (dynamic axial compression, dynamic axial compression-shear), creep and stress relaxation test, device pushout test, core pushout test, subsidence test, etc. were focused on. The experimental techniques using specimen testing method and testing results of available artificial discs were summarized. The experimental methods and research status of finite element analysis were also summarized. Finally, the research trends of AID mechanical performance evaluation were forecasted. The simulator, load, dynamic cycle, motion mode, specimen and test standard would be important research fields in the future.
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The research progress of finite element method (FEM) applied in biomechanics of lumbar fusion and artificial lumbar disc replacement was reviewed and its prospect was forecasted. The main research directions of FEM are optimal selection of operation plans before the surgery, performance evaluation of implanted devices and prediction of postoperative outcomes. Based on the recent research progress, the application prospects of FEM in simulation of personalized surgery, evaluation of elastic implants and postoperative prediction of novel operation method were discussed. By reviewing and prospecting the application of FEM in biomechanical research of lumbar fusion and artificial lumbar disc replacement, the purpose of this paper is to provide theoretical references and practical guidance for the treatment of lumbar diseases in clinic.
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Aiming at the background and significance of biomechanical researches on lumbar interbody fusion, the research progress of interbody cage and interbody fusion was reviewed and its prospect was forecasted. The related work was summarized, including research method of lumbar biomechanics, biomechanics of interbody cage, and biomechanics of lumbar interbody fusion. The main research directions on biomechanical study of lumbar interbody fusion were: modeling refinement of finite element method， geometrical optimization of traditional fusion device, clinical application of new porous fusion device, and diversification of the supplemented fixation method. Finally, the prospect of biomechanics of lumbar interbody fusion was discussed. The review and prospect on biomechanics of lumbar interbody fusion will provide references for clinical treatment of lumbar spine diseases.
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Objective To analyze the characteristics and correlated factors of attempted suicide among psychological aid hotline callers,and provide a reference for suicide prevention and intervention to the domestic psychological aid hotlines.Methods From September,2010 to August,2015,1 299 callers who had the database of attempted suicide among hotline callers were collected.During the calling,the callers were interviewed on their attempted suicides,depression and 10 correlated factors associated with caller's suicidal behaviors.Results Among 1 299 callers who received assessment of suicidal behavior relates factors,361 (27.8％) had evaluated of current suicidal ideation or behavior,223 (17.2％) had history of prior suicidal attempts.There was no significant difference in the incidence of suicide attempts among different gender,age and occupation.1 024 (78.8％) had symptoms of mental illness,794 (61.1％) had symptoms of anxiety,708 (54.5％) had symptoms of depression,864(66.5％) had concomitant two or more symptoms.Compared the caller's occurrence rate of suicidal attempter between single depression and concomitant other symptoms,the results found single depression and concomitant anxiety,concomitant obsession,concomitant panic and concomitant fear were statistically significant.Multiple logistic regression analysis showed that high depression emotion (β=O.389,OR=1.48,95％CI=1.08-2.02),the history of prior attempted suicide (3=0.487,OR=1.63,95％CI=1.19-2.22) and high hopelessness (β=0.618,OR=1.86,95％CI=1.32-2.60) were associated with the caller of ever attempted suicide behaviors.Conclusion Among the callers with attempted suicide,in order to improve the effectiveness of hotline prevention and invention,the psychological consultant should focus on the evaluation of concomitant mental symptoms,high depression emotion,history of prior attempted suicide and hopelessness.
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Objective To characterize hotline callers and related factors in Xiamen psychological aids hotline.Methods The data of 8397 callers who had used hotline were recruited from September 2010 to August 2015.During the calling,the callers were interviewed on their demographic characteristics,main counseling problems and suicidal related factors.Results Among the 8397 callers,1304 (15.5％) were frequent callers.Frequent callers had a high proportion of love and interpersonal problems,learning problems,mental illness problems.After adjusted for demographic characteristics,suicidal ideation or behavior (OR=1.417,95％CI:1.083～1.853),prior suicidal behavior 2 weeks before calling (OR=1.453,95％CI:1.058～1.996),symptoms of mental illness (OR=1.909,95％CI:1.188～3.065) were associated with repeated calls among hotline caller.Conclusion Counselor should pay attention to the suicidal related factors in psychological aids hotline to provide better service for hotline caller.
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Objective To characterize hotline callers and related factors in Xiamen psychological aids hotline.Methods The data of 8397 callers who had used hotline were recruited from September 2010 to August 2015.During the calling,the callers were interviewed on their demographic characteristics,main counseling problems and suicidal related factors.Results Among the 8397 callers,1304 (15.5％) were frequent callers.Frequent callers had a high proportion of love and interpersonal problems,learning problems,mental illness problems.After adjusted for demographic characteristics,suicidal ideation or behavior (OR=1.417,95％CI:1.083～1.853),prior suicidal behavior 2 weeks before calling (OR=1.453,95％CI:1.058～1.996),symptoms of mental illness (OR=1.909,95％CI:1.188～3.065) were associated with repeated calls among hotline caller.Conclusion Counselor should pay attention to the suicidal related factors in psychological aids hotline to provide better service for hotline caller.
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This article reviews the progress of biomechanical studies on anterior cervical fusion and non-fusion surgery in recent years. The similarities and differences between animal and human cervical spines as well as the major three biomechanical test methods are introduced. Major progresses of biomechanical evaluation in anterior cervical fusion and non-fusion devices, hybrid surgery, coupled motion and biomechanical parameters, such as the instant center of rotation, are classified and summarized. Future development of loading method, multilevel hybrid surgery and coupling character are also discussed.
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Animals , Humans , Biomechanical Phenomena , Cervical Vertebrae , General Surgery , Rotation , Spinal Fusion , MethodsABSTRACT
Objective To investigate the relationship between dystrobrevin binding protein 1 (DTNBP1) gene polymorphisms and cognitive function in patients with recurrent depressive disorder.Methods 49 recurrent depressive disorder patients and 60 age-,gender-and education-matched normal controls were recruited in this case-control study.Clinical symptoms were evaluated by HAMD and Wechsler adult memory scale,Wisconsin card sorting test,trail making test(TMT),verbal fluency test (VFT),S troop colorword test were used to evaluate cognitive function.The gene polymorphisms of DTNBP1 were determined by PCR-RFLP technique.SPSS 16.0 was used for statistical analysis.Results The distributions of genotypes in the patients and controls were consistent with Hardy-Weinberg equilibrium(P＞0.05).The time in trail making A task (73.4±30.5 vs 56.2± 11.7),the digital Span (9.6±2.3 vs 8.1±3.0),visual reproduction (9.6±2.3 vs 7.4±3.1),paired association learning (9.7±2.2 vs 6.1±4.2) and Spilling forward (9.1 ±2.4 vs 7.2±2.9) in Wechsler adult memory scale,the categories completed (1.8 ± 1.6 vs 2.5 ± 1.8),total trials (47.6± 1.1 vs 47.3± 0.7) and error numbers (28.5±5.3 vs 24.1±9.3) in WCST performs,and the word meaning interference score (18.4±9.0 vs 25.3±9.5) in Stroop color-word test were monitored.Patients with the genotype of rs9476867 G/G got higher interference number than patients with DTNBP1 rs9476867 C/G and C/C,and patients with the genotype of rs16876738 A/G spent more time to finish TMT-A than patients with rs16876738 G/G and A/A.G/G single nucleotide polymorphism (SNP) of rs9476867 and A/G SNP of rs16876738 affected attention ability.Conclusion DTNBP 1 gene polymorphisms are correlated with cognitive function in recurrent depressive disorder patients.
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BACKGROUND:Artificial Lumbar disc replacement as a new choice for the treatment of degenerative disc disease has aroused widespread concern by clinicians because of the preservation of lumbar vertebra’s biomechanical characteristics during pain eliminating. While the design of the prosthesis structure and material needs further study and validation. OBJECTIVE:To review the structure and material types of several newly designed artificial lumbar discs, then to discuss the trends in the optimization design of prosthesis, in order to provide instruction for the design and assessment of new lumbar artificial disc prosthesis. METHODS:The PubMed database, CNKI database and SinoMed database were searched for related articles. New articles related to artificial lumbar disc structure, material, in vivo and in vitro biomechanics were included. Repetitive studies and stale perspectives were excluded. A total of 46 articles were summarized and discussed in the end. RESULTS AND CONCLUSION:Artificial lumbar disc has developed for nearly 30 years, the design of structure and biological material has been in continuous improvement. At first, we summarized the principle and current situation in the design of movement reservation, movement constraint, instant fixation, base material, weight-bearing material and coating material of artificial lumbar disc prosthesis, then combined with the exist newly in vivo and in vitro biomechanical results to evaluate different kinds of design with the recent research trend to prospect the development of biomimetic design, material improvement, the optimization design of prosthesis and assisted devices.
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BACKGROUND:The basic idea of artificial disc replacement is the intension to minimize the impact on adjacent segments based on the premise of stabilizing index segment, then prevent and reduce the incidence of adjacent segment degeneration. OBJECTIVE:To explore the indications and contraindications of artificial disc replacement, peri-operative economics considerations, long-term complications, as wel as the effect of artificial lumbar disc replacement combined with fusion surgery. METHODS:The PubMed database, CNKI database and SinoMed database over the past decade were searched for the related articles. The retrospective and prospective clinical trials of artificial lumbar disc replacement were included. Repetitive studies and stale perspectives were excluded. A total of 34 articles were summarized and analyzed in the end. RESULTS AND CONCLUSION:Since the first artificial lumbar disc prosthesis designed to be commercial y distributed in 1982, there have been a plenty of clinical trials on lumbar disc replacement. However, there is no answer to many problems that encountered in clinical trials. The effect of the number of replaced segment on the clinical outcomes, the effect of facet joint degeneration on the clinical outcomes, selection of the patients with the history of lumbar disc surgery, age of the patients and the rest time before disc replacement should be taken into consideration in the researches on indications and contraindications of artificial disc replacement. The intraoperative blood loss, operation time and hospital stay after replacement can be used to evaluate whether lumbar disc replacement is better than the traditional lumbar fusion surgery or not. The complications after lumbar disc replacement include heterotopic ossification, implants mechanical failure, and facet joint and adjacent segment degeneration. The combination of lumbar disc replacement and fusion surgery for the treatment of multi-segmental lumbar disc diseases can achieve complement and thus obtaining the efficacy that better than the application of one surgery alone.
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10.3969/j.issn.2095-4344.2013.26.019
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Hepatic perfusion parameters play an important role in detecting and diagnosing diffusion diseases of liver. Based on a hemodynamic model. In this study, we described a fast and accurate method to calculate the perfusion parameters. First, we used a dual-input one-compartment kinetics model to illustrate the distribution of the contrast agent concentration among the body. Then, we used the Gaussian function to fit the scatter concentration data of portal vein and aorta, to obtain a liver agent concentration on function of time. Finally, we solved the model parameters by using Levenberg-Marquardt algorithm, and calculated the perfusion parameters. The results showed that the method proposed in this study could calculate the parameters precisely, and had a prosperous future application possibility.
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Humans , Algorithms , Contrast Media , Hemodynamics , Liver , Physiology , Models, Biological , PerfusionABSTRACT
ObjectiveTo explore the characteristics and risk factors of suicidal ideation among community subjects in Xiamen city and to provide appropriate suicide intervention strategies.MethodsUsing multi-stage stratified cluster sampling,12071 subjects aged 18 years and older were identified in Xiamen City.Their suicidal ideation was recorded with the investigation list made by Beijing Huilongguan Hospital Beijing Suicide Research and Prevention Center.Psychiatrists determined their diagnosis with Diagnostic and Statistical Manual of Mental Disorder 4th edition (DSM-Ⅳ).ResultsA total of 10757 subjects completed the survey,the completion was 89.1％.The life-time prevalence of suicidal ideation was 2.48％ (95％CI:2.19％ ～ 2.77％ ),the prevalence was higher in female(3.00％ ) than male( 1.88％ ) (RR =1.60,95％CI:1.24 ～2.06).Analysis of risk factors by single logistic regression showed that the suicidal ideation of persons were mostly in female,44 years and older group,in rural,not-being married,no medical insurance,poor mental or physical health in last month,being in hospital due to the mental problems,low quality of life,living alone,having blood relatives or acquaintance with suicidal behavior.While the risk factors by muhivariate logistic regression were ranked as follows:having acquaintance with suicidal behavior (OR =3.66,95％CI:2.44 ～5.50),being in hospital because of mental problems (OR =3.30,95％CI:1.08 ～10.09),poor mental health in last month(OR =3.17,95％CI:2.37 ～4.24),any blood relatives having suicidal behavior (OR =2.91,95％CI:1.61 ～ 5.25 ),low of quality of life (OR =2.21,95％CI:1.50 ～ 3.26 ),not-being married (OR =1.73,95％CI:1.28 ～ 2.32),living alone (OR =1.65,95％CI:1.18 ～ 2.32),being female (OR=1.57,95％CI:1.21 ～ 2.05).The prevalence of mental disorders in suicidal ideation was 46.4％.ConclusionThe prevalence of suicidal ideation is significantly higher in female residents than in male.Having acquaintance with suicidal behavior,being in hospital due to the mental problems as well as poor mental health in last month are the main risk factors of suicidal ideation.