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1.
J Clin Neurosci ; 41: 46-49, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28343922

RESUMO

Degeneration of IVD is a progressive and irreversible process and can be evaluated with immunohistochemical examination or radiological grading. MMPs are a family of proteolytic enzymes and involved in the degradation of the matrix components of the IVD. We aimed to compare MMP-1, -2, -3, and -9 expressions with demographic features, visual analogue scale (VAS), Oswestry Disability Index (ODI) and radiological (MRI) grades. The study involved 60 participants. We recorded data about age, complaint, radiological imaging, expression levels of MMP-1, -2, -3, and -9, ODI and VAS for back pain retrospectively. Intervertebral disc degeneration was graded on a 0-5 scale according to the Pfirrmann classification. As a result of the study, the median age was 52.09±12.74years. There were statistical significances between age and MMP-1, and MMP-2. There was a close correlation between grade and MMP-9. We found correlation between the VAS and the MMP-9 expression. In addition, there was relationship between expression of MMP-2 and MMP-1, MMP-3, MMP-9. In conclusion, the expressions of MMP-1 and -2 are increased with aging. There was no relationship between radiological evaluation of IVDD and aging. Increased expression of MMPs affected IVDD positively. The relationship with MMPs is not explained. This study adds to our understanding of the interaction between MMPs and IVDD.


Assuntos
Envelhecimento/patologia , Degeneração do Disco Intervertebral/enzimologia , Metaloproteinases da Matriz Secretadas/biossíntese , Adulto , Idoso , Feminino , Humanos , Degeneração do Disco Intervertebral/diagnóstico , Vértebras Lombares , Imageamento por Ressonância Magnética , Masculino , Metaloproteinase 1 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 3 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Metaloproteinases da Matriz Secretadas/análise , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos
2.
Eur Spine J ; 25(7): 2050-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27095700

RESUMO

PURPOSE: C5 palsy is a well-known complication of cervical spine decompression surgery. The complication develops in both posterior and anterior approaches. We aimed to review reports regarding postoperative C5 palsy in hopes for better prevention and treatment of this morbidity. METHOD: We systematically reviewed and evaluated the abstracts and full texts of the identified papers in the literature. We reviewed and analyzed papers published between January 1970 and February 2015 regarding C5 palsy as a complication of cervical surgical procedures. We made statistical comparisons as much as possible. RESULTS: We did not find any statistical significance between the pathologies (p = 0.088) and between the surgical routes (p = 0.486). There was statistical significance between the types of procedures (p < 0.05). Posterior laminectomy had low incidence of C5 palsy when compared to laminectomy and fusion (p = 0.029) and laminoplasty (p = 0.37). There was no statistically significant difference between anterior cervical decompression and fusion and other procedures (p > 0.05). CONCLUSION: Some studies conclude that anterior procedure is more safe. Of all anterior procedures, the multilevel ACDF had the lowest incidence of C5 palsy. The hybrid technique can be chosen for more than two-vertebra corpectomy. In term of posterior procedures, laminectomy is safer. To prevent C5 palsy, electromyography can be used as a sensitive predictor and selective foraminotomy can be performed.


Assuntos
Vértebras Cervicais/cirurgia , Descompressão Cirúrgica/métodos , Doenças do Sistema Nervoso Periférico/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Compressão da Medula Espinal/cirurgia , Eletromiografia , Foraminotomia/métodos , Humanos , Incidência , Laminectomia/métodos , Laminoplastia/métodos , Compressão da Medula Espinal/etiologia , Raízes Nervosas Espinhais , Espondilose/complicações
4.
Turk J Med Sci ; 45(3): 467-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26281308

RESUMO

BACKGROUND/AIM: To investigate the neuroprotective effects of glucagon-like peptide 2 (Glp-2), which increases cerebral blood flow, on the hippocampal complex after cerebral ischemia/reperfusion (I/R) injury in rats. MATERIALS AND METHODS: Animals were randomized into 4 groups: sham, I/R + 0.9% NaCl, I/R + pre-Glp-2, and I/R + post-Glp-2. Cerebral ischemia was performed via the occlusion of the bilateral internal carotid artery for 40 min and continued with a reperfusion process. At the end of 6 h of reperfusion, animals were decapitated in all groups and brain tissues were removed. Malondialdehyde (MDA) and natural intracellular antioxidant glutathione (GSH) levels and myeloperoxidase (MPO) activities were measured in the left hippocampal tissue. The right hippocampal tissues of all group members were taken for histopathologic study. RESULTS: MDA levels and MPO activities increased from Group I to Group II and decreased from Group II to Groups III and IV. On the other hand, GSH levels were not significantly different among the groups. The number of apoptotic hippocampal tissue cells increased from Group I to Group II and decreased from Group II to Groups III and IV. CONCLUSION: Our preliminary study revealed that Glp-2 treatment may decrease oxidative damage from I/R in cerebral tissue.


Assuntos
Isquemia Encefálica/metabolismo , Peptídeo 2 Semelhante ao Glucagon/farmacologia , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Isquemia Encefálica/patologia , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Glutationa/efeitos dos fármacos , Glutationa/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/efeitos dos fármacos , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo
5.
Turk Neurosurg ; 25(1): 111-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25640554

RESUMO

AIM: In this study, our aim was to examine if matrix metalloproteinase expressions (MMP-1, MMP-2, MMP-3) in patients operated with a lumbar disc hernia diagnosis are different in terms of clinical and neuroradiological findings. MATERIAL AND METHODS: The study included 80 patients treated with micro discectomy for lumbar disc hernia. Degeneration was scored via magnetic resonance (MR) images. MMP-1, MMP-2, and MMP-3 antibodies were used for immunohistochemical evaluation of degenerated disc materials. MMP expressions were compared between primary and recurrent cases, and correlation analysis was conducted. RESULTS: Discectomy material showed higher expression of MMP-1 and MMP-3 in cases of recurrent lumbar disc herniation than in primary herniation. There was no significant relationship between MMP expression and MR degeneration score. CONCLUSION: MMP-1 and MMP-3 expressions were significantly higher in recurrent cases in terms of magnetic resonance degeneration score. We assume that the higher co-expression of MMP-1 and MMP-3 might be used in targeted treatment regiemens in patients with recurrent LDH.


Assuntos
Colagenases/metabolismo , Deslocamento do Disco Intervertebral/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Discotomia , Feminino , Humanos , Deslocamento do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos
6.
APMIS ; 123(3): 199-204, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25556322

RESUMO

Pituitary adenomas are the third most common intracranial tumors. Invasive adenomas account for only 0.1-0.2% of pituitary tumors. SPARC is a matrix glycoprotein that plays a role in progression and invasiveness of neoplasms. In this study, we examined the potential role of SPARC in invasive pituitary adenomas. Forty pituitary adenomas have been examined with histopathological and immunohistochemical techniques. The cohort has been classified into two groups as invasive (n = 25) and non-invasive (n = 15) utilizing the Hardy classification. Formalin fixed tissues have been stained with hematoxylin eosin. Ki-67, p53, and SPARC monoclonal antibodies have been used. We did not detect any significant difference on Ki-67, SPARC, and p53 expression patterns correlating with the pathological subtype or invasiveness. Only 24% of invasive adenomas had Ki-67 levels over 1%. A total of 67.7% non-invasive adenomas had Ki-67 levels below 1%. We did not detect any relation between SPARC levels and invasiveness of pituitary adenomas. Absence of significant SPARC expression in tumor progression, sellar dilatation, erosion and destruction suggest that SPARC scores are not related with invasiveness or progressiveness of pituitary adenomas.


Assuntos
Regulação Neoplásica da Expressão Gênica , Osteonectina/metabolismo , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/patologia , Adulto , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Imunofenotipagem , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Osteonectina/genética , Prognóstico , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
7.
J Spinal Disord Tech ; 28(1): E35-44, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25089674

RESUMO

STUDY DESIGN: Prospective in vivo rat tail model of disk degeneration comparing the effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) injection over various time points and grades of degeneration. OBJECTIVE: To evaluate the effect of timing and disk grade on rhBMP-2 injection in a rat tail model of disk degeneration. SUMMARY OF BACKGROUND DATA: rhBMP-2 stimulates the proliferation of intervertebral disk cells and the secretion of extracellular matrix. However, few in vivo studies have demonstrated whether rhBMP-2 also improves disk degeneration and the severity of disk degeneration beyond which disks cannot be recovered by rhBMP-2 treatment. METHODS: Two coccygeal disks of each rodent subject were punctured percutaneously using an 18 G needle. At 4 weeks after the puncture, disks demonstrating induced degeneration were divided into 3 groups. Groups 1, 2, and 3 were treated with 7.5 µg rhBMP-2 or phosphate buffered saline by injection into the disk at 4, 6, and 8 weeks postpuncture, respectively. Plain radiographs and magnetic resonance images (MRIs) were obtained on the day of puncture and every 2 weeks thereafter until sacrifice. At 6 weeks after injection, each group was killed and examined with histologic and immunohistochemical analysis. RESULTS: According to MRI disk grade evaluation of the degenerative disk, rhBMP-2 significantly improved degeneration grade in group 1 at 2 weeks after injection. According to radiographic disk height index, groups 1 and 2 showed a trend toward improvement at 2 weeks after rhBMP-2 injection. Chondrogenic differentiation was noted on immunohistochemical staining of many disks treated with rhBMP-2. CONCLUSIONS: rhBMP-2 injection of degenerated disks at 4 weeks postpuncture induced a transient improvement in disk grade on MRI and stimulated chondrogenic differentiation. These data suggest rhBMP-2 as a potential therapy for degenerative disk disease.


Assuntos
Proteína Morfogenética Óssea 2/administração & dosagem , Proteína Morfogenética Óssea 2/uso terapêutico , Degeneração do Disco Intervertebral/tratamento farmacológico , Cauda/efeitos dos fármacos , Fator de Crescimento Transformador beta/administração & dosagem , Fator de Crescimento Transformador beta/uso terapêutico , Animais , Proteína Morfogenética Óssea 2/farmacologia , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Injeções , Disco Intervertebral/efeitos dos fármacos , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/patologia , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Proteoglicanas/metabolismo , Punções , Radiografia , Ratos Endogâmicos Lew , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Coloração e Rotulagem , Fatores de Tempo , Fator de Crescimento Transformador beta/farmacologia
8.
Br J Neurosurg ; 29(2): 285-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25365662

RESUMO

OBJECTIVE: Arachnoiditis is an inflammatory process resulting with the fibrosis of arachnoid mater. It can vary in severity from mild thickenings to catastrophic adhesions that ruins subarachnoid space. As a result, arachnoid cysts can be formed. Arachnoid cyst induced by symptomatic spinal arachnoiditis is a rare complication of subarachnoid haemorrhages. In this article, we aimed to present a case of spinal arachnoid cyst formation following subarachnoid haemorrhage and examine similar cases in the literature. CASE REPORT: Forty-six years old, previously healthy female patient has been treated medically for headaches due to perimesencephalic subarachnoid bleeding. Approximately two and a half months later, she started to have severe headaches and diplopia. We detected hydrocephalus and performed ventriculoperitoneal shunt surgery. Two months later, she started to have complaints of weakness in her lower extremities. On neurological examination, she had paraparesis and on spinal magnetic resonance imaging she had an arachnoid cyst lengthening from C7 to T2 and compressing the spinal cord posteriorly. We performed partial laminectomy, drainage of arachnoid cyst and replacement of cystopleural T tube shunt. On follow-up, her lower extremity strength has ameliorated. She was taken into a physical therapy and rehabilitation programme. Three months later she was able to walk with a crutch. CONCLUSION: Subarachnoiditis and associated arachnoid cyst can cause severe morbidity. This rare situation (which especially occurs following subarachnoid haemorrhage of posterior fossa) should be known and physicians should keep in mind that it requires urgent surgical procedure.


Assuntos
Cistos Aracnóideos/cirurgia , Aracnoidite/congênito , Paraparesia/cirurgia , Compressão da Medula Espinal , Hemorragia Subaracnóidea/cirurgia , Cistos Aracnóideos/complicações , Cistos Aracnóideos/diagnóstico , Aracnoidite/diagnóstico , Aracnoidite/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Paraparesia/diagnóstico , Hemorragia Subaracnóidea/diagnóstico , Hemorragia Subaracnóidea/etiologia , Vértebras Torácicas/cirurgia
9.
Turk J Med Sci ; 44(2): 237-42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25536730

RESUMO

AIM: To carry out comparison and correlation analyses of the intervertebral disc (IVD) and vertebral body (VB) volumes in magnetic resonance (MR) images of patients with degenerated and nondegenerated lumbar discs. MATERIALS AND METHODS: MR images were examined retrospectively in 93 patients. Lumbar VB and IVD volumes in T1-T2 weighted sagittal MR images were calculated via the Cavalieri method, a stereological method. Volumetric changes in degenerated and nondegenerated discs were compared. RESULTS: The percentages of degenerated IVDs were 12.9%, 12.9%, 28%, 50.5%, and 52% in discs from levels L1 to L5, respectively. There were no differences in VB volumes between the degenerated and nondegenerated groups for all lumbar vertebra levels. However, significant volumetric decreases were observed in degenerated IVDs for all lumbar vertebra levels, as compared to nondegenerated IVDs. Comparisons of VB volume and IVD volume ratios also revealed decreases, but they were significant only for levels L1 and L4. CONCLUSION: Disc volumes were found to be decreased, although vertebral bodies were not affected in degenerated IVD groups. However, using VB and IVD volume ratios may not always yield reliable results.


Assuntos
Imageamento Tridimensional/métodos , Degeneração do Disco Intervertebral/patologia , Disco Intervertebral/patologia , Vértebras Lombares/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos
10.
Turk Neurosurg ; 24(5): 731-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25269045

RESUMO

AIM: The matrix metalloproteinase (MMP) enzyme family has been shown to be active in tumorigenesis and tumor progression. In this study, we analyzed the prevalence of a guanine insertion in the MMP-1 gene promoter region in meningiomas and its effect on invasion and prognosis. MATERIAL AND METHODS: The study was performed with 33 meningioma patients. We also included 33 healthy patients in the study as a control group. The promoter area was amplified by polymerase chain reaction (PCR) following DNA isolation. The polymorphism was detected by restriction fragment length polymorphism (RFLP). RESULTS: According to the WHO classification of meningiomas, 87.9% of the affected patients were grade 1, and 12.1% were grade 2. In total, 72.7% of the meningioma patients (n=24) had at least one copy of the insertion (2G/1G or 2G/2G genotypes) and 27.3% (n=9) did not (1G/1G). There was no significant difference between the meningioma and control groups according to genotype distribution. CONCLUSION: In this study, the polymorphism in the matrix metalloproteinase-1 gene promoter region did not have an effect on the initiation, growth and progression of meningioma.


Assuntos
Metaloproteinase 1 da Matriz/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Adolescente , Adulto , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , DNA/análise , Feminino , Genótipo , Humanos , Masculino , Neoplasias Meníngeas/patologia , Meningioma/patologia , Pessoa de Meia-Idade , Invasividade Neoplásica , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prognóstico
11.
Asian Spine J ; 8(4): 516-20, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25187872

RESUMO

Pseudotumor cerebri is a condition of increased intracranial pressure in the absence of clinical, laboratory or radiological pathology. Spinal intradural hematoma formation after lumboperitoneal shunt (LPS) implantation is very rare, but it can cause sudden and serious deterioration. In this report, we present a patient who developed an intradural hematoma following LPS operation. A 27-year-old male patient suffering from headaches and progressive vision loss was diagnosed with pseudotumor cerebri. He underwent LPS operation in January 2009. Four hours after the operation, he developed urinary and fecal incontinence with paraparesis (1/5). Lumbar magnetic resonance imaging identified an intradural hematoma at the level of L2-L3, and he was reoperated. The intradural hematoma was removed. Physical therapy was started because of paraparesis. Two months later, the patient's muscle strength had increased to 3/5. Surgeons must remember that, LPS implantation can cause a spinal intradural hematoma in a small percentage of patients, with catastrophic results.

12.
Case Rep Otolaryngol ; 2014: 756280, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25140266

RESUMO

Brain herniation into the middle ear is very rarely seen. In addition to reasons like congenital factors, trauma, and infection, tegmen defect may develop as a result of iatrogenic events secondary to chronic otitis media surgery with or without cholesteatoma. Since it may cause life-threatening complications, patients must be evaluated and monitored for tegmen defect. In this paper, diagnosis and treatment of a brain herniation case due to iatrogenic tegmen defect were described along with relevant literature.

13.
Acta Cir Bras ; 29(4): 268-73, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24760028

RESUMO

PURPOSE: To investigate the neuroprotective effects of Sulindac on the hippocampal complex after global cerebral ischemia/reperfusion (I/R) injury in rats. METHODS: Thirty one Sprague-Dawley rats were used, distributed into group I (sham) n:7 were used as control. For group II (n:8), III (n:8) and IV (n:8) rats, cerebral ischemia was performed via the occlusion of bilateral internal carotid artery for 45 minutes and continued with reperfusion process. 0.3 mL/kg/h 0.9 % sodium chloride was infused intraperitoneally to the Group II rats before ischemia, 5µg/kg/h/0.3 ml sulindac was infused intraperitoneally to the Group III rats before ischemia and 5µg/kg/h/0.3 ml sulindac was infused intraperitoneally to the Group IV rats after ischemia and before reperfusion process. The levels of MDA, GSH and MPO activity were measured in the left hippocampus tissue. The hippocampal tissue of all group members were taken for histopathological study. RESULTS: The MDA and MPO levels increased from group I (control) to group II (I/R) (P<0.05) and decreased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05). Beside these, the GSH levels decreased from group I (control) to group II (I/R) (P<0.05) and increased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05).The number of apoptotic neurons increased from group I (control) to group II (I/R) (P<0.05) and decreased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05). CONCLUSION: The Sulindac may have neuroprotective effects on ischemic neural tissue to prevent the reperfusion injury after ischemia.


Assuntos
Inibidores de Ciclo-Oxigenase/farmacologia , Hipocampo/irrigação sanguínea , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Sulindaco/farmacologia , Animais , Apoptose , Isquemia Encefálica/prevenção & controle , Modelos Animais de Doenças , Glutationa/análise , Hipocampo/patologia , Infusões Parenterais , Malondialdeído/análise , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/análise , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
14.
Acta cir. bras ; 29(4): 268-273, abr. 2014. graf
Artigo em Inglês | LILACS | ID: lil-706956

RESUMO

To investigate the neuroprotective effects of Sulindac on the hippocampal complex after global cerebral ischemia/reperfusion (I/R) injury in rats. Thirty one Sprague-Dawley rats were used, distributed into group I (sham) n:7 were used as control. For group II (n:8), III (n:8) and IV (n:8) rats, cerebral ischemia was performed via the occlusion of bilateral internal carotid artery for 45 minutes and continued with reperfusion process. 0.3 mL/kg/h 0.9 % sodium chloride was infused intraperitoneally to the Group II rats before ischemia, 5μg/kg/h/0.3 ml sulindac was infused intraperitoneally to the Group III rats before ischemia and 5μg/kg/h/0.3 ml sulindac was infused intraperitoneally to the Group IV rats after ischemia and before reperfusion process. The levels of MDA, GSH and MPO activity were measured in the left hippocampus tissue. The hippocampal tissue of all group members were taken for histopathological study. The MDA and MPO levels increased from group I (control) to group II (I/R) (P<0.05) and decreased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05). Beside these, the GSH levels decreased from group I (control) to group II (I/R) (P<0.05) and increased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05).The number of apoptotic neurons increased from group I (control) to group II (I/R) (P<0.05) and decreased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05). The Sulindac may have neuroprotective effects on ischemic neural tissue to prevent the reperfusion injury after ischemia.


Assuntos
Animais , Ratos , Fármacos Neuroprotetores/análise , Isquemia/patologia , Reperfusão , Ferimentos e Lesões , Ratos/classificação
15.
J Neurosurg Spine ; 20(5): 542-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24579877

RESUMO

OBJECT: The center (axis) of rotation (COR) in the lumbar spine has been studied well. However, there is limited information on the kinetic and kinematic consequences of imposed shift in the location of the COR, although this type of shift can be seen after surgeries using motion preservation or dynamic stabilization devices. The objective of this study was to assess the kinetic and kinematic changes in the lumbar spinal segment due to various imposed CORs. METHODS: A 3D finite element model of the L4-5 segment was constructed and validated. The segment was loaded under a 7.5-Nm bending moment while constrained to rotate about various imposed CORs in the sagittal and axial motion planes. Range of motion, ligament forces, facet loads, and disc stresses were measured. RESULTS: The present model showed an agreement with previous in vitro and finite element studies under the same load and boundary conditions. Range of motion, facet forces, disc stresses, and ligament loads showed a strong association with the location of the COR. CONCLUSIONS: Acute alterations in the location of the COR can significantly change the load sharing characteristics within the spine segment. The normal location of the COR is a result of the tendency of the vertebra to move in the path of least cumulative resistance.


Assuntos
Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiologia , Amplitude de Movimento Articular/fisiologia , Tomografia Computadorizada por Raios X , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Rotação
16.
Adv Orthop ; 2013: 753470, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23662211

RESUMO

Fusion and rigid instrumentation have been currently the mainstay for the surgical treatment of degenerative diseases of the spine over the last 4 decades. In all over the world the common experience was formed about fusion surgery. Satisfactory results of lumbar spinal fusion appeared completely incompatible and unfavorable within years. Rigid spinal implants along with fusion cause increased stresses of the adjacent segments and have some important disadvantages such as donor site morbidity including pain, wound problems, infections because of longer operating time, pseudarthrosis, and fatigue failure of implants. Alternative spinal implants were developed with time on unsatisfactory outcomes of rigid internal fixation along with fusion. Motion preservation devices which include both anterior and posterior dynamic stabilization are designed and used especially in the last two decades. This paper evaluates the dynamic stabilization of the lumbar spine and talks about chronologically some novel dynamic stabilization devices and thier efficacies.

17.
J Neurosurg Spine ; 18(6): 617-26, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23600587

RESUMO

OBJECT: The goal of this study was to investigate the effect of ligament failure on the instantaneous center of rotation (ICR) in the lower lumbar spine. METHODS: A 3D finite element model of the L4-5 segment was obtained and validated. Ligament failure was simulated by reducing ligaments in a stepwise manner from posterior to anterior. A pure bending moment of 7.5 Nm was applied to the model in 3 anatomical planes for the purpose of validation, and a 6-Nm moment was applied to analyze the effect of ligament failure. For each loading case, ligament reduction step, and load increment, the range of motion of the segment and the ICR of the mobile (L-4) vertebra were calculated and characterized. RESULTS: The present model showed a consistent increase in the range of motion as the ligaments were removed, which was in agreement with the literature reporting the kinematics of the L4-5 segment. The shift in the location of the ICR was below 5 mm in the sagittal plane and 3 mm in both the axial and coronal planes. CONCLUSIONS: The location of the ICR changed in all planes of motion with the simulation of multiple ligament injury. The removal of the ligaments also changed the load sharing within the motion segment. The change in the center of rotation of the spine together with the change in the range of motion could have a diagnostic value, revealing more detailed information on the type of injury, the state of the ligaments, and load transfer and sharing characteristics of the segment.


Assuntos
Simulação por Computador , Análise de Elementos Finitos , Ligamentos Articulares/fisiologia , Vértebras Lombares/fisiologia , Modelos Anatômicos , Amplitude de Movimento Articular/fisiologia , Fenômenos Biomecânicos/fisiologia , Humanos , Ligamentos Articulares/patologia , Rotação
18.
Spine (Phila Pa 1976) ; 38(10): 806-13, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23197010

RESUMO

STUDY DESIGN: In vivo rodent model. OBJECTIVE: Investigate the effect of systemic corticosteroid administration on soft-tissue inflammation after local delivery of recombinant human bone morphogenetic protein-2 (rhBMP-2). SUMMARY OF BACKGROUND DATA: Corticosteroid use in cases of soft-tissue inflammation associated with the use of rhBMP-2 has been reported in clinical studies, but the effectiveness of its use and appropriate timing remain unclear. METHODS: Absorbable collagen sponges were implanted with control or rhBMP-2 into the lumbar region of rats subcutaneously and intramuscularly. Four groups were studied: group I, control sponge only; group 2, BMP-2 sponge only; group III, BMP-2 sponge and preoperative intraperitoneal methylprednisolone (MPSS); group IV, BMP-2 sponge with MPSS given on day 2. Using magnetic resonance imaging, inflammation was assessed in terms of soft tissue edema volume at 0, 2, 4, and 7 days. Rats were sacrificed after 7 days for gross and histological analysis. RESULTS: The peak mean intramuscular inflammatory volume occurred on day 2 in all groups. Group II (BMP-2 without MPSS) had a significantly higher peak mean inflammatory volume (405.46 mm) on day 2 than that of groups I (266 mm), III (278 mm), and IV (291 mm) (P = 0.001). No significant difference in intramuscular soft-tissue inflammation was observed between the control group and the groups receiving MPSS on day 0 or day 2 at any time point. No differences in the area of inflammatory cell infiltrate surrounding the sponge was observed histologically, after sacrificing them, in groups treated with BMP-2. CONCLUSION: Systemic MPSS administration reduced soft tissue edema associated with rhBMP-2 as measured by magnetic resonance imaging, but no effect was observed on the histological area of inflammation. Further studies are required to elucidate if there is any benefit to the use of corticosteroid administration in reducing the area of inflammation associated with the use of rhBMP-2.


Assuntos
Proteína Morfogenética Óssea 2/efeitos adversos , Modelos Animais de Doenças , Inflamação/prevenção & controle , Metilprednisolona/farmacologia , Músculos/efeitos dos fármacos , Fator de Crescimento Transformador beta/efeitos adversos , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Sistemas de Liberação de Medicamentos , Edema/induzido quimicamente , Edema/prevenção & controle , Humanos , Inflamação/induzido quimicamente , Injeções Intraperitoneais , Imageamento por Ressonância Magnética , Metilprednisolona/administração & dosagem , Músculos/patologia , Ratos , Ratos Endogâmicos Lew , Proteínas Recombinantes/efeitos adversos , Tampões de Gaze Cirúrgicos , Fatores de Tempo , Resultado do Tratamento
19.
Orthop Rev (Pavia) ; 4(2): e22, 2012 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-22802990

RESUMO

Low-back pain is a common problem in neu-rosurgery practice, and an algorithm has been developed for assessing these cases. However, one subgroup of these patients shares several clinical features and these individuals are not easy to categorize and diagnose. We present our observations for 8 of these patients, individuals with low-back pain caused by atypical annulus fibrosus rupture (AAR). The aim of this study is to show the consequences of overlooked annular tears on acute onset of low back pain. Eight patients with acute-onset severe low-back pain were admitted. Physical examinations were normal and each individual was examined neurologically and assessed with neuroradiologic studies [plain x-rays, magnetic resonance imaging (MRI), discography and computed tomography (CT) discography]. AAR was ultimately diagnosed with provocative discography. In all cases, MRI showed a healthy disc or mild degeneration, whereas discography and CT discography demonstrated disc disease. Anterior interbody cage implantation was performed in 3 of the 8 cases and posterior dynamic stabilization was carried out in 3 cases. The other 2 individuals refused surgery, and we were informed that one of them developed disc herniation at the affected level 1 year after our diagnosis. Clinical and radiological outcomes were evaluated. In cases where AAR is suspected, MRI, discography, and CT discography should be performed in addition to routine neuroradiologic studies.

20.
J Neurosurg Spine ; 17(2): 124-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22681618

RESUMO

OBJECT: In most cases of lumbar disc herniation, the primary problem is usually limited to radicular pain due to nerve compression on the herniated side, which is generally limited to the side of operation. The aim of this study was to reevaluate the side of the surgical approach in a selected group of patients with leg pain and contralateral lumbar disc herniation. METHODS: Included in this study were a total of 5 patients with lumbar disc herniations who presented with contralateral symptoms and neurological signs. In all cases, patients underwent a microdiscectomy from the side ipsilateral to the herniated lumbar disc, the side contralateral to the motor deficits and leg pain. RESULTS: The symptoms and signs, to some extent, resolved during the immediate postoperative period. There were no postoperative complications. CONCLUSIONS: The findings confirm that performing a laminotomy via the side of the herniation is sufficient for this group of patients.


Assuntos
Discotomia/métodos , Deslocamento do Disco Intervertebral/cirurgia , Laminectomia/métodos , Vértebras Lombares/cirurgia , Adulto , Feminino , Humanos , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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