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PURPOSE: Our study aimed to evaluate non-inferiority of ProDisc-C to anterior cervical discectomy and fusion (ACDF) in terms of clinical outcomes and incidence of adjacent segment disease (ASD) at 24-months post-surgery in Asian patients with symptomatic cervical disc disease (SCDD). METHODS: This multicentre, prospective, randomized controlled trial was initiated after ethics committee approval at nine centres (China/Hong Kong/Korea/Singapore/Taiwan). Patients with single-level SCDD involving C3-C7-vertebral segments were randomized (2:1) into: group-A treated with ProDisc-C and group-B with ACDF. Assessments were conducted at baseline, 6-weeks, 3/6/12/18/24-months post-surgery and annually thereafter till 84-months. Primary endpoint was overall success at 24-months, defined as composite of: (1) ≥ 20% improvement in neck disability index (NDI); (2) maintained/improved neurologic parameters; (3) no implant removal/revision/re-operation at index level; and (4) no adverse/severe/life-threatening events. RESULTS: Of 120 patients (80ProDisc-C,40ACDF), 76 and 37 were treated as per protocol (PP). Overall success (PP) was 76.5% in group-A and 81.8% in group-B at 24-months (p = 0.12), indicating no clear non-inferiority of ProDisc-C to ACDF. Secondary outcomes improved for both groups with no significant inter-group differences. Occurrence of ASD was higher in group-B with no significant between-group differences. Range of motion (ROM) was sustained with ProDisc-C but lost with ACDF at 24-months. CONCLUSION: Cervical TDR with ProDisc-C is feasible, safe, and effective for treatment of SCDD in Asians. No clear non-inferiority was demonstrated between ProDisc-C and ACDF. However, patients treated with ProDisc-C demonstrated significant improvement in NDI, neurologic success, pain scores, and 36-item-short-form survey, along with ROM preservation at 24-months. Enrolment difficulties resulted in inability to achieve pre-planned sample size to prove non-inferiority. Future Asian-focused, large-scale studies are needed to establish unbiased efficacy of ProDisc-C to ACDF.
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Degeneração do Disco Intervertebral , Fusão Vertebral , Substituição Total de Disco , Povo Asiático , Vértebras Cervicais/cirurgia , Discotomia/métodos , Seguimentos , Humanos , Degeneração do Disco Intervertebral/etiologia , Degeneração do Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral , Estudos Prospectivos , Amplitude de Movimento Articular , Fusão Vertebral/métodos , Substituição Total de Disco/métodos , Resultado do TratamentoRESUMO
INTRODUCTION: Data is currently lacking regarding association between the cholecystectomy/hepatectomy/pancreatectomy and the development of osteoporotic fracture. A retrospective cohort study was conducted to investigate the relationship between cholecystectomy/hepatectomy/pancreatectomy and the subsequent risk of developing osteoporotic fracture. MATERIALS AND METHODS: Patients having undergone cholecystectomy, hepatectomy, or pancreatectomy between 2000 and 2012 were selected from the All Population Based Hospitalization File as the surgery cohort (n = 304,081), which was frequency matched with the control cohort (n = 304,081). The Cox proportional hazard model and Kaplan-Meier analysis were applied to measure the hazard ratios and the cumulative incidence of osteoporotic fracture. RESULTS: A total of 1136 patients in the surgery cohort and 1179 patients in the control cohort were newly diagnosed with osteoporotic fracture. The overall osteoporotic fracture risk in the surgery cohort was 1.12-fold higher [95% confidence interval (CI), 1.03-1.21]. Specifically, surgery cohort had higher vertebral fracture risk than non-surgery cohort [adjusted hazard ratio (aHR) 1.12, Cl, 1.03-1.22]. In addition, patients underwent cholecystectomy (includes open and laparoscopic approaches), hepatectomy (only open approach), and pancreatectomy group (only open approach) were 1.10 (95% CI, 1.01-1.19), 1.49 (95% CI, 1.10-2.01), and 1.88 (95% CI, 1.23-2.87) times more likely to develop osteoporotic fracture, respectively. No significant difference of osteoporotic fracture risk was observed between open and laparoscopic cholecystectomy. The risk of osteoporotic fracture was significantly increased in females, patients aged ≥ 40 years old, and patients with some comorbidity. CONCLUSIONS: Patients post cholecystectomy, hepatectomy, or pancreatectomy significantly increased risk of developing osteoporotic fracture, suggesting closer attention in post-operative care is needed.
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Colecistectomia/efeitos adversos , Hepatectomia/efeitos adversos , Fraturas por Osteoporose/epidemiologia , Pancreatectomia/efeitos adversos , Fraturas da Coluna Vertebral/epidemiologia , Estudos de Coortes , Comorbidade , Feminino , Hospitalização , Humanos , Incidência , Estimativa de Kaplan-Meier , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de RiscoRESUMO
PURPOSE: A slouching posture during smartphone usage increases gravitational loadings on the cervical spine, which may lead to neck pain and degeneration. The objective of the present study was to investigate the head, neck and trunk angles in different smartphone-usage postures, as well as the posture-correction effects and comfort scores of three neck collars. METHODS: This was a prospective cohort study in which 41 healthy young subjects aged 18-25 were recruited. The head, neck and trunk angles were measured in all participants during a neutral position and three smartphone-using postures, including sitting with and without back support and standing. The postural correction and comfort scores of three collars (Aspen Vista, Sport-aid and our customized 3D printed collars) were compared. RESULTS: Smartphone use increased the head and neck flexion angles in all postures, and sitting without back support showed the greatest head and neck flexion angles. The posture-correcting effect of the customized collar was better than the Aspen Vista and Sport-aid collars. In addition, the customized collar was more comfortable to wear than the other two collars in most contact areas. CONCLUSION: Smartphone use increased both the head and neck flexion in different postures, and the proposed customized 3D-printed cervical collar significantly reduced the head and neck angles. These slides can be retrieved under Electronic Supplementary Material.
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Braquetes , Pescoço/fisiologia , Postura/fisiologia , Smartphone , Adolescente , Adulto , Voluntários Saudáveis , Humanos , Estudos Prospectivos , Amplitude de Movimento Articular/fisiologia , Adulto JovemRESUMO
PURPOSE: The diagnosis of painful cemented vertebrae resulting from failed PV is not clearly defined in literature. This report evaluates the effectiveness of modified dynamic radiographs in diagnosing painful cemented vertebrae resulting from failed PV. METHODS: From January 2011 to June 2015, 345 patients with a total of 399 VCFs underwent PV at our institution. Among the 345 patients, 27 patients underwent repeated PV at the cemented vertebrae because of persisting or recurrent pain after vertebroplasty. The prevertebroplasty examinations included routine radiographs, modified dynamic radiographs, and MRI. Kyphotic angles and the anterior vertebral body height (AVBH) were measured. The image findings in routine radiographs, modified dynamic radiographs, and MRI were compared. Finally, a visual analog scale was used to measure the outcome. RESULTS: The patients ranged in age from 67 to 90 years. MRI revealed a moderate amount of fluid (definite diagnosis of refracture) in the cemented vertebrae in seven patients, bone edema without fluid in nine patients, and bone edema with minimal fluid in ten patients. The rate of diagnosis of painful cemented vertebrae according to MRI was 27% (7/26). The difference in the kyphotic angle between sitting and supine cross-table lateral radiographs was -9.36° ± 5.20° (P < 0.001). The difference in AVBH was 8.08 ± 3.21 mm (P < 0.001). All 27 patients were confirmed to have dynamic mobility according to the modified dynamic radiographs. CONCLUSIONS: When the diagnosis of painful cemented vertebrae is questionable, modified dynamic radiographs can help diagnose painful cemented vertebrae resulting from failed PV.
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Fraturas por Compressão/cirurgia , Fraturas por Osteoporose/cirurgia , Dor Pós-Operatória/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Vertebroplastia , Idoso , Idoso de 80 Anos ou mais , Cimentos Ósseos , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Medição da Dor , Radiografia , Estudos Retrospectivos , Falha de Tratamento , Vertebroplastia/instrumentaçãoRESUMO
BACKGROUND: Giant invasive sacral schwannomas are rare tumors. Surgical excision is the standard treatment and total resection is performed if feasible. Advances in three-dimensional (3D) imaging technology have facilitated treatment designs of complex surgical procedures. OBJECTIVE: Our aim was to evaluate virtual surgical planning, computer-aided design (CAD), and manufacturing with 3D printing technology of the customized osteotomy guiding device in giant invasive sacral schwannoma resection. METHODS: A digital 3D model of the sacrum, including the giant invasive sacral schwannoma, was rendered from patient computer tomography (CT) images. The surgeon chose excision margins of the tumor. Based on the virtual surgical planning, the customized guiding tool for osteotomy was designed and manufactured using the CAD and 3D printing. RESULTS: We used the guiding block to successfully excise a giant sacral schwannoma using only a posterior approach to achieve gross total resection. No augmented spinal instrumentation was used to prevent iatrogenic spinal instability. Clinical symptoms resolved dramatically after operation. No spinal instability occurred during follow-up. CONCLUSION: With the assistance of an image-based customized osteotomy guiding device, we achieved both goals of tumor resection and bone preservation in giant sacral schwannoma resection. With thorough surgical planning, this technology can be applied to the complex surgical procedures easily and reliably.
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Desenho Assistido por Computador , Neurilemoma/cirurgia , Osteotomia/métodos , Sacro/cirurgia , Neoplasias da Coluna Vertebral/cirurgia , Cirurgia Assistida por Computador/métodos , Feminino , Humanos , Instabilidade Articular/patologia , Neurilemoma/patologia , Osteotomia/instrumentação , Impressão Tridimensional , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
BACKGROUND/PURPOSE: Premature adjacent-level degeneration has been attributed to vertebral fusion, but spondylolisthesis has not been reported as a pathological factor responsible for the degeneration of adjacent disc and facet joint. We hypothesized that the degeneration of disc and facet joints in the adjacent levels is correlated with spondylolisthesis. METHODS: Magnetic resonance images of 35 symptomatic young adults (16-29 years old) with low-grade L5-S1 spondylolytic spondylolisthesis (Meyerding Grade 1 or 2) and 50 symptomatic young referents (20-29 years old) with L5-S1 disc herniation without spondylolisthesis were recruited to compare the differences between disc and facet-joint degenerations at the olisthetic and adjacent levels using the Mantel extension test. RESULTS: There were statistically significant degenerative changes of the discs and facet joints at the olisthetic and adjacent levels of patients with spondylolytic spondylolisthesis compared with the reference group. There is a trend that the disc and facet joints degenerate the most at the olisthetic level and become less affected at adjacent levels away from the lesion of pars defect. CONCLUSION: Low-grade spondylolytic spondylolisthesis was associated with significant degenerations of the disc and facet joints at olisthetic and adjacent levels in young adults.
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Disco Intervertebral/patologia , Espondilolistese/diagnóstico por imagem , Articulação Zigapofisária/patologia , Adolescente , Adulto , Feminino , Humanos , Disco Intervertebral/diagnóstico por imagem , Dor Lombar/etiologia , Imageamento por Ressonância Magnética , Masculino , Amplitude de Movimento Articular , Estudos Retrospectivos , Ciática/etiologia , Espondilolistese/fisiopatologia , Taiwan , Adulto Jovem , Articulação Zigapofisária/diagnóstico por imagemRESUMO
PURPOSE: To assess the use of the dual-energy computed tomographic (CT) virtual noncalcium technique in the evaluation of bone marrow edema in vertebral compression fractures. MATERIALS AND METHODS: This prospective study was approved by the institutional review board; informed consent was obtained from all patients. Sixty-three consecutive patients with 112 thoracic and/or lumbar vertebral compression fractures were studied between January 2011 and April 2012. All patients underwent both dual-energy CT (100 kV and Sn140 kV, where Sn indicates the use of a 0.4-mm tin filter) and magnetic resonance (MR) imaging. Dual-energy CT data were postprocessed by using a three-material decomposition algorithm for generating noncalcium images of the collapsed bodies. Two radiologists evaluated for the presence of abnormal attenuation alterations in the bone marrow by using color-coded maps and measured CT numbers on noncalcium grayscale images. Bone sclerosis and intravertebral air were evaluated with CT scans. MR images served as the reference standard. CT numbers were subjected to receiver operating characteristic curve analysis. RESULTS: MR imaging depicted 46 edematous and 66 nonedematous vertebral compression fractures. Eighty-two bodies were classified as having less than 50% sclerosis and/or air. Significant differences in noncalcium CT numbers between edematous and nonedematous vertebral compression fractures were found for both readers (P < .0001). CT numbers for the diagnosis of bone marrow edema on the basis of MR imaging revealed areas under the receiver operating characteristic curve of 0.799 and 0.841 for readers 1 and 2, respectively (P = .56). Use of a cutoff value of -80 to differentiate edematous vertebral bodies resulted in a sensitivity of 96.3%, specificity of 98.2%, and accuracy of 97.6% in the group of vertebral bodies with less than 50% sclerosis and/or air. CONCLUSION: Dual-energy CT virtual noncalcium images were able to depict bone marrow in the collapsed vertebral bodies, especially in those with less than 50% sclerosis and/or air.
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Medula Óssea/patologia , Edema/diagnóstico por imagem , Fraturas por Compressão/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
BACKGROUND: The lumbar range of motion has traditionally been used to assess disability in patients with low back disorders. Controversy exists about how movement ranges in static positions or in a single straight plane is related to the functional status of the patients. The trunk circumduction, as the result of neuromuscular coordination, is the integrated movements from three dimensions. The functional workspace stands for the volume of movement configuration from the trunk circumduction and represents all possible positions in three dimensions. By using single quantitative value, the functional workspace substitutes the complicated joint linear or angular motions. The aim of this study is to develop the functional workspace of the trunk circumduction (FWTC) considering possible functional positions in three dimensional planes. The reliability of the trunk circumduction is examined. METHODS: Test-retest reliability was performed with 18 healthy young subjects. A three-dimensional (3-D) Motion Analysis System was used to record the trunk circumduction. The FWTC was defined and calculated based on the volume of the cone that was formed as the resultant scanned area of markers, multiplied by the length of the body segment. The statistical analysis of correlation was performed to describe the relation of maximal displacements of trunk circumduction and straight planes: sagittal and coronal. RESULTS: The results of this study indicate that the movement of trunk circumduction measured by motion analysis instruments is a reliable tool. The ICC value is 0.90-0.96, and the means and standard deviations of the normalized workspace are: C7 0.425 (0.1162); L1 0.843 (0.2965); and knee 0.014 (0.0106). Little correlations between the maximal displacement of trunk circumduction and that of straight planes are shown and therefore suggest different movement patterns exist. CONCLUSIONS: This study demonstrates high statistical reliability for the FWTC, which is important for the potential development as the functional assessment technique. The FWTC provides a single integrated value to represent angular and linear measurements of different joints and planes. Future study is expected to carry out the FWTC to evaluate the amount of workspace for the functional status of patients with low back injuries or patients with spinal surgery.
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Ergonomia , Movimento/fisiologia , Tronco/fisiologia , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Articulações/fisiologia , Joelho/fisiologia , Dor Lombar/diagnóstico , Dor Lombar/fisiopatologia , Região Lombossacral/fisiologia , Masculino , Amplitude de Movimento Articular/fisiologia , Reprodutibilidade dos Testes , Software , Adulto JovemRESUMO
INTRODUCTION: Magnetic resonance images (MRI) fluid sign and intravertebral vacuum phenomenon of the plain radiograph are considered as the characteristic radiological findings for vertebral osteonecrosis after spinal fractures. We aim to study the association between the radiological and histopathologic findings of vertebral osteonecrosis through the use of an open retrieval of specimens. MATERIALS AND METHODS: Twenty consecutive patients (54-84 years, mean 73 years) of unstable vertebral compression fractures treated with anterior corpectomy and fusion were included. All the images and pathologies were correlated, especially the histopathologic changes to the fluid sign and vacuum phenomenon. RESULTS: MRI fluid signs and the histopathologic findings of vertebral osteonecrosis were significantly correlated and both were noted in the first 5 months after injury. The power of the fluid sign in diagnosing vertebral osteonecrosis was better than that of the intravertebral vacuum phenomenon (diagnostic odds ratio 65 vs. 2, sensitivity 86 vs. 50%, specificity 100 vs. 67%). CONCLUSION: MRI fluid sign is more predictable to diagnose vertebral osteonecrosis in operative case, especially within the initial 5 months after injury.
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Osteonecrose/diagnóstico , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas por Compressão/complicações , Fraturas por Compressão/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Fraturas da Coluna Vertebral/cirurgia , Fusão VertebralRESUMO
Study design and objection: Intradural disc herniation is a unusual disease associated with spinal surgery. The definitive diagnosis of intradural herniation depends on intraoperative findings. Summary of background data: We present the case of a 63-year-old woman with backache and left sciatica radiation for more than two months. The L2/3 laminectomy and discectomy were performed after magnetic resonance imaging (MRI) study; however, no disc rupture was noted during surgery. Follow-up lumbar spine MRI revealed one large, ruptured disc. The patient underwent revision surgery with durotomy. The large intradural disc was found and removed piece by piece. Methods Results and Conclusions: Intradural disc herniation, especially large herniation, is hard to diagnose specifically despite the progression of neuroradiologic imaging techniques. A durotomy procedure should be considered if there is a missing ruptured disc or a palpable intradural mass during surgery.
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OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) has long been regarded as a gold standard in the treatment of cervical myelopathy. Subsequently, cervical artificial disc replacement (c-ADR) was developed and provides the advantage of motion preservation at the level of the intervertebral disc surgical site, which may also reduce stress at adjacent levels. The goal of this study was to compare clinical and functional outcomes in patients undergoing ACDF with those in patients undergoing c-ADR for cervical spondylotic myelopathy (CSM). METHODS: A systematic literature review and meta-analysis were performed using the Embase, PubMed, and Cochrane Central Register of Controlled Trials databases from database inception to November 21, 2021. The authors compared Neck Disability Index (NDI), SF-36, and Japanese Orthopaedic Association (JOA) scores; complication rates; and reoperation rates for these two surgical procedures in CSM patients. The Mantel-Haenszel method and variance-weighted means were used to analyze outcomes after identifying articles that met study inclusion criteria. RESULTS: More surgical time was consumed in the c-ADR surgery (p = 0.04). Shorter hospital stays were noted in patients who had undergone c-ADR (p = 0.04). Patients who had undergone c-ADR tended to have better NDI scores (p = 0.02) and SF-36 scores (p = 0.001). Comparable outcomes in terms of JOA scores (p = 0.24) and neurological success rate (p = 0.12) were noted after the surgery. There was no significant between-group difference in the overall complication rates (c-ADR: 18% vs ACDF: 25%, p = 0.17). However, patients in the ACDF group had a higher reoperation rate than patients in the c-ADR group (4.6% vs 1.5%, p = 0.02). CONCLUSIONS: At the midterm follow-up after treatment of CSM, better functional outcomes as reflected by NDI and SF-36 scores were noted in the c-ADR group than those in the ACDF group. c-ADR had the advantage of retaining range of motion at the level of the intervertebral disc surgical site without causing more complications. A large sample size with long-term follow-up studies may be required to confirm these findings in the future.
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BACKGROUND: Vertebral compression fractures, resulting in significant pain and disability, commonly occur in elderly osteoporotic patients. However, the current literature lacks long-term follow-up information related to image parameters and bone formation following vertebroplasty. PURPOSE: To evaluate new bone formation after vertebroplasty and the long-term effect of vertebroplasty. METHODS: A total of 157 patients with new osteoporotic compression fractures who underwent vertebroplasty were retrospectively analyzed. The image parameters, including wedge angles, compression ratios, global alignment, and new bone formation, were recorded before and after vertebroplasty up to three years postoperatively. RESULTS: The wedge angle improved and was maintained for 12 months. The compression ratios also improved but gradually deteriorated during the follow-up period. New bone formation was found in 40% of the patients at 36 months, and the multivariate analysis showed that this might have been related to the correction of the anterior compression ratio. CONCLUSIONS: Vertebroplasty significantly restored the wedge angles and compression ratios up to one year postoperatively, and new bone formation was noted on plain radiographs, which increased over time. Last, the restoration of vertebral parameters may contribute to new bone formation.
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The International Society for Clinical Densitometry (ISCD) launched the professional certification course in early 1996 and was introduced to Taiwan by the Taiwanese Osteoporosis Association in 2002. Disclosing the associated factors of passing the certification examination would be valuable to advance the teaching skill of faculties and clinical excellence of professionals. From June 2002 to July 2009, 732 attendees (male/female=621/111) of 12 professional certification courses (11 courses delivered in Chinese) were enrolled for analysis. All subjects were asked to complete a questionnaire including demographics and professional experience at the time of course registration. After certification examination, subjects were dichotomized as either pass or fail group for analyzing the determinants of pass rate statistically. The average pass rate of the 12 examinations was 75.3% (n=551). In univariate analysis, the age (p<0.001) and hospital level (p<0.001) showed significant differences between the pass and fail groups. However, in the multivariate logistic analysis, only the age (odds ratio [OR]=0.907, 95% confidence interval [CI]: 0.867-0.949, p<0.001) and clinical experience (attending physician vs resident: OR=3.210, 95% CI: 1.215-8.485, p=0.019) were the independent determinants for passing the course. Professionals who are relatively younger or attending physicians have higher pass rate of ISCD course in Taiwan. The fact that only limited predisposing factors might influence the pass rate reflects the efficient design of course delivering. For any knowledge level of professionals who have interest in the excellence of osteoporosis diagnosis and management, the ISCD course is recommended.
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Certificação , Densitometria , Avaliação das Necessidades , Adulto , Fatores Etários , Competência Clínica , Serviço Hospitalar de Educação/normas , Educação Médica Continuada/normas , Avaliação Educacional , Feminino , Humanos , Masculino , Corpo Clínico Hospitalar/educação , Corpo Clínico Hospitalar/normas , Pessoa de Meia-Idade , Análise Multivariada , TaiwanRESUMO
Despite improvements in cancer treatments resulting in higher survival rates, the proliferation and metastasis of tumors still raise new questions in cancer therapy. Therefore, new drugs and strategies are still needed. Midazolam (MDZ) is a common sedative drug acting through the γ-aminobutyric acid receptor in the central nervous system and also binds to the peripheral benzodiazepine receptor (PBR) in peripheral tissues. Previous studies have shown that MDZ inhibits cancer cell proliferation but increases cancer cell apoptosis through different mechanisms. In this study, we investigated the possible anticancer mechanisms of MDZ on different cancer cell types. MDZ inhibited transforming growth factor ß (TGF-ß)-induced cancer cell proliferation of both A549 and MCF-7 cells. MDZ also inhibited TGF-ß-induced cell migration, invasion, epithelial-mesenchymal-transition, and Smad phosphorylation in both cancer cell lines. Inhibition of PBR by PK11195 rescued the MDZ-inhibited cell proliferation, suggesting that MDZ worked through PBR to inhibit TGF-ß pathway. Furthermore, MDZ inhibited proliferation, migration, invasion and levels of mesenchymal proteins in MDA-MD-231 triple-negative breast cancer cells. Together, MDZ inhibits cancer cell proliferation both in epithelial and mesenchymal types and EMT, indicating an important role for MDZ as a candidate to treat lung and breast cancers.
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BACKGROUND: Finite element analysis results will show significant differences if the model used is performed under various material properties, geometries, loading modes or other conditions. This study adopted an FE model, taking into account the possible asymmetry inherently existing in the spine with respect to the sagittal plane, with a more geometrically realistic outline to analyze and compare the biomechanical behaviour of the lumbar spine with regard to the facet force and intradiscal pressure, which are associated with low back pain symptoms and other spinal disorders. Dealing carefully with the contact surfaces of the facet joints at various levels of the lumbar spine can potentially help us further ascertain physiological behaviour concerning the frictional effects of facet joints under separate loadings or the responses to the compressive loads in the discs. METHODS: A lumbar spine model was constructed from processes including smoothing the bony outline of each scan image, stacking the boundary lines into a smooth surface model, and subsequent further processing in order to conform with the purpose of effective finite element analysis performance. For simplicity, most spinal components were modelled as isotropic and linear materials with the exception of spinal ligaments (bilinear). The contact behaviour of the facet joints and changes of the intradiscal pressure with different postures were analyzed. RESULTS: The results revealed that asymmetric responses of the facet joint forces exist in various postures and that such effect is amplified with larger loadings. In axial rotation, the facet joint forces were relatively larger in the contralateral facet joints than in the ipsilateral ones at the same level. Although the effect of the preloads on facet joint forces was not apparent, intradiscal pressure did increase with preload, and its magnitude increased more markedly in flexion than in extension and axial rotation. CONCLUSIONS: Disc pressures showed a significant increase with preload and changed more noticeably in flexion than in extension or in axial rotation. Compared with the applied preloads, the postures played a more important role, especially in axial rotation; the facet joint forces were increased in the contralateral facet joints as compared to the ipsilateral ones at the same level of the lumbar spine.
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Análise de Elementos Finitos , Disco Intervertebral/fisiologia , Dor Lombar/fisiopatologia , Vértebras Lombares/fisiologia , Articulação Zigapofisária/fisiologia , Fenômenos Biomecânicos/fisiologia , Simulação por Computador , Humanos , Pressão Hidrostática/efeitos adversos , Disco Intervertebral/anatomia & histologia , Deslocamento do Disco Intervertebral/fisiopatologia , Vértebras Lombares/anatomia & histologia , Modelos Anatômicos , Pressão/efeitos adversos , Amplitude de Movimento Articular/fisiologia , Espondilose/fisiopatologia , Estresse Mecânico , Suporte de Carga/fisiologia , Articulação Zigapofisária/anatomia & histologiaRESUMO
Intervertebral disc (IVD) is an avascular tissue under hypoxic condition after adulthood. Our previous data showed that inflammatory cytokines (interleukin (IL)-1ß), IL-20, and bone morphogenetic protein-2 (BMP-2) play important roles in the healing process after disc injury. In the current study, we investigated whether IL-1ß, IL-20, or BMP-2 modulate the expression of pro-inflammatory cytokines, chemotaxis factor, and angiogenesis factor on IVD cells under hypoxia. IVD cells were isolated from patients with intervertebral disc herniation (HIVD) at the levels of L4-5 and L5-S1. We found that the expression of IL-1ß, IL-20, BMP-2, hypoxia-inducible factor (HIF)-1α, IL-6, IL-8, angiogenetic factor (vascular endothelial growth factor (VEGF)), chemotactic factor (monocyte chemoattractant protein 1 (MCP-1)), and matrix metalloproteinase-3 (MMP-3) was upregulated in IVD cells under hypoxia conditions. In addition, IL-1ß upregulated the expression of pro-inflammatory cytokines (IL-6 and IL-8), VEGF, MCP-1, and disc degradation factor (MMP-3) in IVD cells under hypoxia conditions. IL-20 upregulated MCP-1 and VEGF expression. BMP-2 also upregulated the expression of MCP-1, VEGF, and IL-8 in IVD cells under hypoxia conditions. Treatment with antibody against IL-1ß decreased VEGF and MMP-3 expression, while treatment with IL-20 or BMP-2 antibodies decreased MCP-1, VEGF, and MMP-3 expression. Moreover, IL-1ß modulated both the expression of IL-20 and BMP-2, but IL-20 only modulated BMP-2 either under a hypoxic or normoxic condition. Therefore, we concluded that the inflammation, chemotaxis, matrix degradation, and angiogenesis after disc herniation are influenced by the hypoxic condition and controlled by IL-1ß, IL-20, and BMP-2.
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Few studies have investigated the factors related to the disability and physical function in degenerative lumbar spondylolisthesis using axially loaded magnetic resonance imaging (MRI). Therefore, we aimed to investigate the effect of axial loading on the morphology of the spine and the spinal canal in patients with degenerative spondylolisthesis of L4-5 and to correlate morphologic changes to their disability and physical functions. From March 2003 to January 2004, 32 consecutive cases (26 females, 6 males) with degenerative L4-5 spondylolisthesis, grade 1-2, intermittent claudication, and low back pain without sciatica were included in this study. All patients underwent unloaded and axially loaded MRI of the lumbo-sacral spine in supine position to elucidate the morphological findings and to measure the parameters of MRI, including disc height (DH), sagittal translation (ST), segmental angulation (SA), dural sac cross-sectional area (DCSA) at L4-5, and lumbar lordotic angles (LLA) at L1-5 between the unloaded and axially loaded condition. Each patient's disability was evaluated by the Oswestry Disability Index (ODI) questionnaire, and physical functioning (PF) was evaluated by the Physical Function scale proposed by Stucki et al. (Spine 21:796-803, 1996). Three patients were excluded due to the presence of neurologic symptoms found with the axially loaded MRI. Finally, a total of 29 (5 males, 24 females) consecutive patients were included in this study. Comparisons and correlations were done to determine which parameters were critical to the patient's disability and PF. The morphologies of the lumbar spine changed after axially loaded MRI. In six of our patients, we observed adjacent segment degeneration (4 L3-L4 and 2 L5-S1) coexisting with degenerative spondylolisthesis of L4-L5 under axially loaded MRI. The mean values of the SA under pre-load and post-load were 7.14 degrees and 5.90 degrees at L4-L5 (listhetic level), respectively. The mean values of the LLA under pre-load and post-load were 37.03 degrees and 39.28 degrees , respectively. There were significant correlations only between the ODI, PF, and the difference of SA, and between PF and the post-loaded LLA. The changes in SA (L4-L5) during axial loading were well correlated to the ODI and PF scores. In addition, the LLA (L1-L5) under axial loading was well correlated to the PF of patients with degenerative L4-L5 spondylolisthesis. We suggest that the angular instability of the intervertebral disc may play a more important role than neurological compression in the pathogenesis of disability in degenerative lumbar spondylolisthesis.
Assuntos
Avaliação da Deficiência , Vértebras Lombares/patologia , Vértebras Lombares/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Espondilolistese/diagnóstico , Espondilolistese/fisiopatologia , Idoso , Fenômenos Biomecânicos/fisiologia , Dura-Máter/patologia , Dura-Máter/fisiopatologia , Feminino , Humanos , Claudicação Intermitente/etiologia , Claudicação Intermitente/fisiopatologia , Disco Intervertebral/patologia , Disco Intervertebral/fisiopatologia , Deslocamento do Disco Intervertebral/diagnóstico , Deslocamento do Disco Intervertebral/fisiopatologia , Instabilidade Articular/diagnóstico , Instabilidade Articular/fisiopatologia , Dor Lombar/etiologia , Dor Lombar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Limitação da Mobilidade , Amplitude de Movimento Articular/fisiologia , Índice de Gravidade de Doença , Estresse Mecânico , Inquéritos e Questionários , Suporte de Carga/fisiologia , Articulação Zigapofisária/patologia , Articulação Zigapofisária/fisiopatologiaRESUMO
One primary focus of the present study was to clarify the crucial resorption-location relationship of a recently developed single-phase TTCP-derived calcium phosphate cement (CPC) implanted in rabbit femur in a systematic and quantitative way. Gross examination of retrieved CPC/bone composite samples indicated that the CPC implant did not evoke inflammatory response, necrosis or fibrous encapsulation in surrounding bony tissues. Histological examination revealed excellent CPC-host bone bonding. At 4 weeks, the resorption-induced voids between terminals of bone defects and implants were largely filled with new bone. CPC resorption, new blood vessels, osteocytes, osteons and osteoblast-like cells lining up with active new bone were observed at remodeling sites. At 12 weeks, a new bone network was developed within femoral defect, while CPC became islands incorporated in the new bone. At this stage, crevices filled with lamellar new bone structure were frequently observed. At 24 weeks, bone ingrowth and remodeling activities became so extensive that the interface between residual cement and new bone became less identifiable. In general, at all implant locations the resorption ratio values increased with implantation time, while at all implantation times the resorption ratios decreased from the exterior (cortical site) to the interior (cancellous site) of implants. At the end of 24 weeks, CPC was almost completely resorbed and bone remodeling almost finished at the cortical site.
Assuntos
Cimentos Ósseos/metabolismo , Remodelação Óssea , Fosfatos de Cálcio/metabolismo , Fêmur/cirurgia , Implantes Experimentais , Implantes Absorvíveis , Animais , Cimentos Ósseos/química , Regeneração Óssea , Fosfatos de Cálcio/análise , Fosfatos de Cálcio/química , Fêmur/química , Fêmur/patologia , Cinética , Masculino , Teste de Materiais , Microscopia , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios XRESUMO
Minimally invasive surgeries including endoscopic surgery and mini-open surgery are current trend of spine surgery, and its main advantages are shorter recovery time and cosmetic benefits, etc. However, mini-open surgery is easier and less technique demanding than endoscopic surgery. Besides, anterior spinal fusion is better than posterior spinal fusion while considering the physiological loading, back muscle function, etc. Therefore, we aimed to introduce the modified "mini-open anterior spine surgery" (MOASS) and to evaluate the feasibility, effectiveness and safety in the treatment of various anterior lumbar diseases with this technique. A total of 61 consecutive patients (46 female, 15 male; mean age 58.2 years) from 1997 to 2004 were included in this study, with an average follow-up of 24-52 (mean 43) months. The disease entities included vertebral fracture (20), failed back surgery (13), segmental instability or spondylolisthesis (10), infection (8), herniated disc (5), undetermined lesion for biopsy (4), and hemivertebra (1). Lesions involved 13 cases at T12-L1, 18 at L1-L2, 18 at L2-L3, 22 at L3-L4 and 11 at L4-L5 levels. All patients received a single stage anterior-only procedure for their anterior lumbar disease. We used the subjective clinical results, Oswestry disability index, fusion rate, and complications to evaluate our clinical outcome. Most patients (91.8%) were subjectively satisfied with the surgery and had good-to-excellent outcomes. Mean operation time was 85 (62-124) minutes, and mean blood loss was 136 (minimal-250) ml in the past 6 years. Hospital stay ranged from 4-26 (mean 10.6) days. Nearly all cases had improved back pain (87%), physical function (90%) and life quality (85%). Most cases (95%) achieved solid or probable solid bony fusion. There were no major complications. Therefore, MOASS is feasible, effective and safe for patients with various anterior lumbar diseases.
Assuntos
Vértebras Lombares/cirurgia , Procedimentos Ortopédicos/métodos , Doenças da Coluna Vertebral/cirurgia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodosRESUMO
Objective We assessed our results of short-segment decompression and fixation for osteoporotic thoracolumbar fractures with neurological deficits. Methods We evaluated 20 elderly patients (age, 60-89 years; mean, 73.2 years) with osteoporotic thoracolumbar fractures and neurological deficits. They underwent short-segment decompression and fixation and followed up for 40.6 (range, 24-68) months. A visual analog scale (VAS) and the Oswestry Disability Index (ODI) were used to measure back pain and disability. We also analyzed patients' radiologic findings and neurological status. Perioperative and postoperative complications were recorded. Results At the latest follow-up, the average VAS score for back pain and ODI scores had significantly improved. The radiologic assessment showed significant improvements in local kyphosis, anterior vertebral height, and the vertebral wedge angle compared with the original measures. Neurological function also improved in 18 of 20 patients. No major complications occurred perioperatively. Our techniques included preservation of the posterior ligament complex, decortication of facet joints for fusion, no tapping to increase the screw insertional torque, pre-contouring of the rods according to the "adaptive" curve obtained from postural reduction, and postoperative spinal bracing. Conclusions Posterior short-segment decompression and fixation could be an effective surgical option for osteoporotic thoracolumbar burst fractures with neurological deficits.