bluuebunny/crossref_metadata_2025_split huggingface dataset:
X-rays and scans can fail to differentiate hip pathology from lumbar spinal stenosis: Two case reports
Authors: Singh Ravindra , Kim Hyeun-Sung , Adsul Nitin , Kashlan Osama Nezar , Woon Oh Sung , Noh Jung Hoon , Moon Soeng Cheol , Park Chang Hwan , Jang Il Tae , Hoon Oh Seong 
Published: August 2019

Background:
Occasionally, hip pathologies may present alone or combined with lumbar spine pathology, especially lumbar stenosis. Although the history and clinical examination may help differentiate between the two, hip X-rays alone without accompanying magnetic resonance imaging (MRI) studies may prove unreliable.

Case Descriptions:
Case 1 – A 72-year-old male presented with the sudden onset of severe back and left posterior thigh pain. Straight leg raising test was positive at 70° (right) and 60° (left), and he had left lower extremity numbness and weakness. The lumbar MRI showed L5-S1 spinal stenosis. Although X-rays of both hips were negative, the MRI showed bilateral femoral neck fractures. He underwent screw fixation of the hip fractures and later underwent endoscopic decompression of the spinal stenosis. Case 2 – A 35-year-old male presented with low backache and right hip pain of 1 month’s duration. The neurological examination was normal, except for positive straight leg raising bilaterally at 60°. The spine MRI was normal. However, despite negative X-ray of both hips, the hip MRI revealed avascular necrosis (AVN) of both femoral heads requiring subsequent orthopedic management.

Conclusion:
Hip pathology may mimic lumbar spinal stenosis. In the two cases presented, plain X-rays failed to document hip fractures (case 1) and AVN (case 2), respectively, both of which were later diagnosed on MRI studies.
Penetrating spinal cord injury: A case report and literature review
Authors: Mackowsky Matthew , Hadjiloucas Nicole , Campbell Stuart , Bulauitan Constantine 
Published: August 2019

Background:
Penetrating spinal cord injury (pSCI) is uncommon in civilian settings. However, there is a lack of consensus regarding perioperative management and thresholds for operative intervention. This review explores the various trends in the management of pSCI along with a literature review.

Case Description:
A 34-year-old male presented with a gunshot wound (GSW) to the left chest. Injuries included a pneumothorax, diaphragmatic injury, splenic injury, multiple small bowel injuries, transverse colon injury, and a bullet lodged at the L5 spinal level. The patient underwent chest tube placement, an exploratory laparotomy, splenectomy, diaphragmatic repair, multiple small bowel resections, and a transverse colon resection. Later on, the patient required a lumbar laminectomy for wound debridement and bullet excision.

Conclusion:
The standards for the surgical management of pSCI are poorly defined. Older studies suggested that >7 days of antibiotics decreased the risk of infection associated with HVI while shorter regimens correlated with higher rates of spinal and neurologic infections (meningitis, paraspinal abscess, and osteomyelitis). Newer studies fail to confirm the benefit of extended antimicrobial therapy, noting no increased infections with 48 h or less of antibiotic use while suggesting increased risks of long-term antibiotic prophylaxis (i.e., antimicrobial resistance and Clostridium difficile infection). There is no current role for steroids in the treatment of pSCI, and routine operative management is no longer necessarily indicated.
Cervical spondylodiscitis caused by Candida albicans in a non-immunocompromised patient: A case report and review of literature
Authors: Huang Shiwei , Kappel Ari D. , Peterson Catherine , Chamiraju Parthasarathi , Rajah Gary B. , Moisi Marc D. 
Published: August 2019

Background:
Fungal cervical spondylodiscitis is rare and accounts for less than 1% of all cervical, thoracic, and lumbar vertebral osteomyelitis and discitis.

Case Description:
A 32-year-old non-immunocompromised male presented with persistent neck pain and paresthesias. The magnetic resonance imaging of the cervical spine demonstrated a contrast-enhancing erosive lesion involving the cervical C6 and C7 vertebral bodies accompanied by epidural phlegmon. Blood culture was negative. The patient underwent a C6 and C7 anterior corpectomy with instrumented fusion (e.g., expandable cage C5 to T1). Intraoperatively, frank pus was noted within the C6-C7 disc space and was accompanied by thick prevertebral and epidural phlegmon extending from C5 to T1. Intraoperative cultures grew Candida albicans. Three days later, a C6-C7 laminectomy with C4-T2 posterior instrumented fusion was performed; the cultures again grew C. albicans. The patient was treated with intravenous micafungin for 14 days followed by 6–12 months of 400 mg oral fluconazole daily.

Conclusion:
There are few cases in literature where non-immunocompromised patients developed fungal cervical spondylodiscitis. Prompt diagnosis and appropriate management are critical to effectively treat these patients. Surgical intervention may warrant corpectomy, discectomy, and operative debridement followed by long-term targeted antifungal therapy.
Rupture immediately after growth of unruptured intracranial aneurysms during follow-up
Authors: Yanagawa Taro , Harada Yoichi , Hatayama Toru , Kono Takuji 
Published: August 2019

Background:
The annual rupture rate of small unruptured intracranial aneurysms (UIAs) <5 mm is generally low; further, small UIAs are often treated conservatively. While the growth of aneurysms during follow-up is associated with a high risk of rupture, the urgency for surgical treatment of asymptomatic enlarged UIAs remains controversial. We experienced two patients in whom UIAs ruptured shortly after asymptomatic growth during follow-up.

Case Description:
A 1-mm right middle cerebral artery aneurysm was incidentally found in a 63-year-old woman. Preventive surgery was planned because the aneurysm grew rapidly; however, the aneurysm ruptured preoperatively. A 68-year-old woman had a small (4 mm) aneurysm at the left internal carotid-posterior communicating artery. The aneurysm grew rapidly after many years. Several hours after magnetic resonance imaging was performed, she presented to the hospital with loss of consciousness, and a diagnosis of subarachnoid hemorrhage due to the ruptured aneurysm was made.

Conclusion:
UIAs that rapidly increase during follow-up may be regarded as impending ruptured aneurysms.
Minimally invasive lateral transpsoas approach for lumbar corpectomy and stabilization
Authors: Srikantha Umesh , Lokanath Yadhu Kasetti , Hari Akshay , Nirmala S. , Varma Ravi Gopal 
Published: August 2019

Background:
Here, we present our experience with the minimally invasive (MI) transpsoas approach for lumbar corpectomy and stabilization. Transpsoas approach accesses the lumbar spine and includes both the direct lateral interbody fusion and extreme lateral interbody fusion techniques. Both procedures utilize a tubular retractor system which facilitates adequate retraction and direct visualization of the target, while supposedly reducing soft tissue trauma.

Case Description:
We evaluated two patients, one with a traumatic L2 wedge compression fracture and the other with an L3 pathological compression fracture due to multiple myeloma. Both patients underwent MI transpsoas lumbar corpectomy, anterior column reconstruction with an expandable cage, and posterior pedicle screw instrumentation to correct a kyphotic deformity. Both patients were mobilized on the 1st postoperative day and experienced significant postoperative pain relief.

Conclusion:
In two cases involving L2 and L3 compression fractures, MI transpsoas lumbar corpectomy was safely performed, with reduced perioperative and postoperative morbidity. Here, the transpsoas approach also allowed for early mobilization, adequate postoperative biomechanical stability, and resulted in immediate good outcomes.
A surgical case of cerebellar tuberculoma caused by a paradoxical reaction while on therapy for tuberculosis spondylitis
Authors: Ninomiya Atsuhiko , Saito Atsushi , Ishida Tomohisa , Inoue Tomoo , Inoue Takashi , Ezura Masayuki , Suzuki Shinsuke , Uenohara Hiroshi , Tominaga Teiji 
Published: August 2019

Background:
A paradoxical reaction (PR) is a phenomenon in which the primary tuberculous lesion worsens or another de novo tuberculous lesion appears while on anti-tuberculosis therapy. Here, we report a rare case of cerebellar tuberculoma caused by a PR during therapy for lumbar tuberculous spondylitis (Pott’s disease).

Case Description:
A 47-year-old male with human immunodeficiency virus seronegative was diagnosed with lumber tuberculous spondylitis (Pott’s disease) and prescribed anti-tuberculous agents. His lower back pain and inflammatory condition recovered after initiation of anti-tuberculous therapy. Two months later, he complained of headache, nausea, and staggering. Magnetic resonance images revealed a ring-enhanced lesion located at the cerebellar hemisphere extending to the vermis, which caused perifocal edema and bilateral ventriculomegaly. These findings were consistent with his symptoms of hydrocephalus. He did not have preceding clinical findings of meningitis, and a PR was suggested to cause de novo aggregation of cerebellar tuberculoma. A lesionectomy was performed, and the surgical specimen was pathologically diagnosed as a tuberculoma. He recovered well from neurological disorders after the resection.

Conclusion:
De novo formation of intracranial tuberculoma alone caused by a PR without preceding meningitis is very rare. Lesionectomy is needed for intracranial tuberculoma, which manifests as a mass effect, as well as antituberculous therapy.
Which factors predict the loss of cervical lordosis following cervical laminoplasty? A review of various indices and their clinical implications
Authors: Sharma Ravi , Borkar Sachin A. , Goda Revanth , Kale Shashank S. 
Published: August 2019

Background:
Many patients undergoing laminoplasty develop postoperative loss of cervical lordosis or kyphotic alignment of cervical spine despite sufficient preoperative lordosis. This results in poor surgical outcomes.

Methods:
Here, we reviewed the relationship between multiple radiological parameters of cervical alignment that correlated with postoperative loss of cervical lordosis in patients undergoing laminoplasty.

Results:
Patient with a high T1 slope (T1S) has more lordotic alignment of the cervical spine preoperatively and is at increased risk for the loss of cervical lordosis postlaminoplasty. Those with lower values of difference between T1S and Cobb’s angle (T1S-CL) and CL-T1S ratio have higher risks of developing a loss of the cervical lordosis postoperatively. Alternatively, C2-C7 lordosis, neck tilt, cervical range of motion, and thoracic kyphosis had no role in predicting the postlaminoplasty kyphosis.

Conclusion:
Among various radiological parameters, the preoperative T1S is the most important factor in predicting the postoperative loss of the cervical lordosis/alignment following laminoplasty.
Intraoperative imaging and navigation for C1-C2 posterior fusion
Authors: Harel Ran , Nulman Maya , Knoller Nachshon 
Published: August 2019

Background:
Cervical axial spine fusion is challenging as the anatomy is extremely variable, and screw misplacement can lead to severe complications. C1 lateral mass screws and C2 pedicle screws are routinely placed under either fluoroscopic guidance or imaging-assisted navigation. Here, we compared the two for axial screw placement.

Methods:
We retrospectively evaluated patients’ treated from 2011–2016 utilizing the Harm’s procedure for C1-C2 screw fixation performed under either fluoroscopic guidance (nine patients) or image-assisted O-arm navigation (five patients). The groups had similar demographic and risk factors. Variables studied included operative time, estimated blood loss (EBL), accuracy of screw placement, screw reposition rates, and reoperation rates.

Results:
The mean EBL was 555CC and 260CC, respectively (not a significant difference) utilizing fluoroscopic versus O-arm navigation. Of interest, the mean surgical duration was 27 min longer in the O-arm versus fluoroscopy group (P = 0.03). Ten C2 pedicle screws were performed using O-arm navigation. Alternatively, as 9 of 18 C2 pedicles were considered “risky” for the placement of fluoroscopic-guided pedicle screws, laminar screws were utilized. Although the accuracy rate of C1 and C2 screw placement was higher for the navigated group, this finding was not significant. Similarly, despite complications involving two unacceptably placed screws from the fluoroscopic guidance group, there were no neurological sequelae.

Conclusion:
Axial cervical spine instrumentation is challenging. Utilization of Imaging-assisted navigation increases the accuracy and safety of screw placement.
Missed thoracic myelopathy: Do not throw the hammer away yet
Authors: Shields Lisa B. E. , Iyer Vasudeva G. , Zhang Yi Ping , Shields Christopher B. 
Published: August 2019

Background:
Spinal stenosis may result in myelopathy, radiculopathy, and neurogenic claudication. It is often difficult to differentiate between these conditions. A comprehensive history and physical examination and a magnetic resonance imaging (MRI) of the entire spine accurately confirm the diagnosis.

Case Description:
Here, we report a patient with low back and progressive bilateral lower extremity pain, numbness, and weakness with bowel incontinence, urinary retention, and gait abnormalities. A lumbar MRI demonstrated multilevel severe spondylosis/stenosis from L3-S1. The patient underwent a decompressive lumbar laminectomy from L3-5. However, the patient continued to experience the same symptoms postoperatively along with flexor spasms of the left leg, dystonic posturing of the left foot, hyperactive bilateral patellar and Achilles deep tendon reflexes, and a Babinski sign. An NCV of the legs revealed no lumbar radiculopathy. The thoracic MRI, however, demonstrated severe spondylosis at the T11-12 level attributed to a large synovial cyst. Following decompression/cyst resection, the patient’s symptoms partially resolved within 1 postoperative month.

Conclusion:
Spinal surgeons should be alert to the potential for overlapping symptoms/signs of thoracic myelopathy and lumbar myeloradiculopathy. If there are features of upper and lower motor neuron disease, MR scans of the entire spine are necessary before lumbar surgical decompression to identify significant cephalad surgical pathology.
Computed tomography perfusion in detecting malignant middle cerebral artery infarct
Authors: Lee Chun Lin , Kandasamy Regunath , Mohammad Raffiq Mohammed Azman Bin 
Published: August 2019

Background:
Computed tomography perfusion (CTP) is an emerging modality which produces maps of time-to- peak (TTP), cerebral blood flow (CBF), and cerebral blood volume (CBV), with a computerized automated map of the infarct and penumbra. This modality provides a better evaluation of the extent of infarction, making it a potential method for assessing patients suffering from large middle cerebral artery (MCA) infarctions.

Methods:
A prospective cohort study of all patients in Hospital Kuala Lumpur, Malaysia, who presented with the clinical diagnosis of a large MCA infarction within 48 h of onset were subjected to CT brain, and CTP scans on admission and were followed up to determine the development of malignant infarction requiring surgical decompression.

Results:
CTP parameters were generally lower in patients with malignant brain infarct (MBI) group compared to the nonMBI group. The largest mean difference between the group was noted in the TTP values (P = 0.005). CTP parameters had a comparable positive predictive value (83%–90%) and high net present value (88–93). CBF with cutoff value of >32.85 of the hemisphere could accurately predict malignant infarctions in 81.4% of cases. The National Institutes of Health Stroke Scale score of more than 13.5 was also found to be able to accurately determine malignant infarct (97.6%). Functional outcome of patients based on Glasgow outcome scale was similar on discharge, however, showed improvement at 6 months during reviewed base on modified Rankin scale (P < 0.001).

Conclusion:
CTP parameters should be included in the initial evaluation of patients to predict malignant brain infarction and facilitate surgical treatment of large MCA infarctions.

Key messages:
CT perfusion parameters have an important role in predicting malignant brain infarction and should be included in the initial evaluation of patients to facilitate the early identification and surgical treatment of large middle cerebral artery infarctions, to improve patient’s prognosis.
O uso das tecnologias da informação e comunicação como recursos didáticos no ensino de física
Authors: Loureiro Bruna Cristina Oliveira 
Published: August 2019

Este trabalho apresenta os resultados relativos a pesquisa bibliográfica realizada com o objetivo de investigar se as Tecnologias da Informação e Comunicação - TIC’s estão sendo inseridas como recursos didáticos no processo de ensino e aprendizagem da disciplina de Física de modo a proporcionar uma aprendizagem significativa aos alunos, uma vez que as tecnologias se mostram com grande potencial de contribuir para o processo de ensino e aprendizagem. Reuniu-se os autores que versam sobre o tema como Ricardo e Freire (2007), Voelzke E Araújo (2014), Souza (2013) dentre outros. Buscou-se verificar se o uso das TIC’s está sendo efetivado no Ensino de Física, quais dificuldades encontradas para a implementação entre outras questões identificadas nos textos dos autores. Concluiu-se que está ocorrendo a implantação das TIC’s, no entanto não em sua plena potencialidade, os professores encontram barreiras estruturais, como a falta de espaço, equipamentos e internet na escola como também em sua formação, que deveria ser continuada a ponto de estar sempre se aperfeiçoando para poder se adequar as tecnologias que vão surgindo.
O conceito de simetria na Física
Authors: Moreira Marco Antonio 
Published: August 2019

A ideia de simetria é abordada, inicialmente, como parte do cotidiano e depois como um conceito central na Física. São apresentados significados do conceito no contexto da Física e são dados exemplos. É destacada a relação entre simetria e leis de conservação, expressa no teorema de Noether. Boa parte do texto é dedicada ao conceito de quebra espontânea de simetria. A proposta do texto é a de enfatizar o papel da simetria na construção do conhecimento físico.
Effect of Viscosity Parameter on Numerical Simulation of Fire Damaged Concrete Columns
Authors: Hussain Iqrar , Yaqub Muhammad , Ehsan Adeel , Rehman Safi Ur 
Published: August 2019

The assessment of the residual strength of post-heated concrete structural members in a professional way is a prime factor to take a decision about the restoration or destruction of fire-damaged structure. This Paper explores the numerical modelling of RC square columns damaged by exposure to heat at 5000C, unjacketed. Software ABAQUS was used for numerical modelling of fire damaged compression member i-e column. The main objective of this study is prediction of axial load and axial deformation of fire damaged concrete using finite element studies. Moreover, a parametric nonlinear finite element (FE) research is carried out to check the effect of viscosity parameters on numerical simulation of fire damaged concrete columns. For the said objectives, numerical simulation of existing experimental study of fire damaged RC columns is conducted with varied values of viscosity parameters. The numerical analysis (Finite Element Modeling) indicated that axial load capacity decreases and axial deformation increases after exposure to fire. The experimental and numerical studies are compared in terms of load displacement analysis. The use of optimum viscosity parameter and its definition to FEM improves significantly the performance of convergence and reduces analysis time of numerical simulations of RC square columns. Moreover, a good agreement was found between the experimental and the finite model results.
Increasing the Contribution of GFRP Bars on the Compressive Strength of Concrete Columns with Circular Cross Section
Authors: Tabkhi Wayghan Amir Reza , Mofid Massood , Babaei Ravandi Behnam , Zinati Yazdi Seyed Morteza 
Published: August 2019

Corrosion of steel in concrete elements is a major issue in concrete structures. In order to overcome this matter, Glass Fiber Reinforced Polymer (GFRP) reinforcement is being used in concrete members from almost 20 years ago. Although it has been used and developed in recent years, there are still some uncertainties for the application of FRP reinforcement, especially in concrete columns. Most codes such as ACI, CSA, JSCE & etc. neglects the effect of these reinforcements or they do not permit them in compressive concrete elements. In this essay, it has been shown that these rebar can contribute significantly in compressive strength of concrete columns if the column confinement is provided sufficiently. In order to achieve the required confinement to reach a sharp contribution of GFRP longitudinal rebar in concrete columns, the spiral of FRP rebar with small pitches around longitudinal rebar is taken into account. This leads to higher strains of concrete which can result in a higher contribution of FRP longitudinal rebar. Foremost, equations related to the compressive strength of concrete columns considering the influence of spiral confinement will be carried out. Then, a parametric study will be performed, and the effects of pitch, concrete strength, column diameter, the quantity of longitudinal rebar and concrete cover will be investigated.
PWM output CMOS Stress Sensor based in PiezoFET current mirrors
Authors: Ramirez Bohorquez Jose Luis , Fruett Fabiano 
Published: August 2019

This work shows the design and characterization of a stress sensor based on piezoFET current mirrors with a Pulse Width Modulated output, a compact device designed to be integrated in any CMOS process which is suitable to estimate the stress state over the silicon surface. The multi-terminal device integrates the piezo-MOSFETs with different alignments within current mirrors with the bias circuits to extract differential currents, which are related to the different stress components at the surface of the device. The analog current outputs are converter into single-bit digital signal using a Pulse Width modulator. In the absence of stress, the duty cycle of the output is 50%, but if stress is applied, the mismatches in the currents generate a shift in the duty cycle proportional to the stress. Since there are piezoFET aligned in different directions, it is possible to add the currents to isolate effect of the different stress components. The piezoFET current mirrors and the PWM stress sensor were characterized using a four-point bending test; a controlled uniaxial stress in a range [5MPa, 70MPa] was applied aligned to the main crystallographic directions of the device surface, while both the currents at the piezoFET mirrors and the digital output are observed. The analog outputs show a linear behaviour with stress and fit the equations from the piezoresistive effect while the duty cycle of the digital output varies also linearly around the 50%.