bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Rights and Network Power
Authors: Khor Lena
Published: February 2011

This article analyzes how the globalization of human rights discourse enables victims of rights violations to gain presence and influence on a global stage through the concept of network power. This article argues against criticisms of human rights discourse as another form of Western cultural imperialism. This article uses the case of the Rwandan Paul Rusesabagina, especially his representations in Philip Gourevitch’s We Wish to Inform You That Tomorrow We Will Be Killed with Our Families: Stories from Rwanda , Terry George’s film Hotel Rwanda , and Rusesabagina’s autobiography An Ordinary Man to illustrate this point.
“War” in the Jurisprudence of the Inter-American Court of Human Rights
Authors: Burgorgue-Larsen Laurence , de Torres Amaya Úbeda
Published: February 2011

How have the Inter-American human rights bodies dealt with the notion of war, which has been transformed over time into the notion of (internal and international) “armed conflicts”? This question has guided the first part of this study, which sets out the various types of conflicts that have occurred in the American continent. These situations (armed conflicts, internal strife, State terrorism) have produced a wide range of legal qualifications, used by both the Inter-American Commission and Court of human rights in their case-law. This conceptual delimitation carried out by these two bodies is all the more important as it affects the law that applies to armed conflicts. Indeed, by analyzing this question, the everlasting debate on the relationship between International Law on Human Rights and International Humanitarian Law reappears. The second part of this study therefore focuses on the issue of discovering whether and in which way jus in bello has found its place in the Inter-American Human Rights bodies’ case-law. As the active political life of Latin American societies has shown, the study of the different applicable legal regimes also requires looking into the “state of emergency” Law, an issue which has been shaped by the Inter-American Court and Commission’s work.
Between Rights Talk and Bible Speak: The Implementation of Equal Treatment Legislation in Orthodox Reformed Communities in The Netherlands
Authors: Oomen Barbara
Published: February 2011

This article discusses the responses to a number of recent court cases concerning the equal treatment of women and homosexuals amongst Dutch orthodox reformed in the semi-public sphere ( e.g. political parties, schools). In doing so, this article applies and refines legal anthropological theories on the realization of rights in a context of cultural and religious diversity. It also specifically addresses the responses to court cases launched “from the outside” in the context of a western country with a tradition of code law. These cases have an adverse effect on discussions of equal treatment within the communities concerned.
Developing the Right to Work: Intersecting and Dialoguing Human Rights and Economic Policy
Authors: Sarkin Jeremy , Koenig Mark
Published: February 2011

This article explores why the “right to work” remains underdeveloped through an analysis of its theoretical origins and developmental path. First, the article explores specific content of the right to work, as well as the international legal instruments that generate that content. Second, the article examines the development of the right over time, and the debates that have shaped it. This discussion progresses into analysis of the different perspectives and approaches to the right to work emerging from the human rights and labor movements. The differences in approach between policy makers and those in the human rights sector, caused largely by developments in economic theories, is also examined to help explain the contemporary status of the right to work. Ultimately, the article discusses the challenges of bringing human rights dialogue to bear on economic decision-making, and concludes with recommendations for the future development of the right to work.
α-Synuclein in Parkinson disease and other neurodegenerative disorders
Authors: Eller Michael , Williams David R.
Published: February 2011

With the aging population in the Western hemisphere, neurodegenerative parkinsonism and dementia will become two of the great public health challenges of this century. A major pillar in the effort to treat these conditions will be the shift from symptomatic treatment to disease modifying therapy. This step will absolutely require cheap and reliable biomarkers; patients will need to be diagnosed before irreversible change has occurred. α-Synuclein (αS) is a recent candidate biomarker for Lewy body neurodegeneration. It is a 140 amino acid protein that forms the pathological substrate in idiopathic Parkinson's disease (IPD), dementia with Lewy bodies (DLB), as well as multiple system atrophy (MSA), a group of disorders collectively known as the synucleopathies. Biomarker research has investigated αS in blood, skin and cerebrospinal fluid (CSF). Plasma assays have demonstrated inconsistent results but CSF assays show a higher degree of uniformity, mostly demonstrating lower levels of αS in patients with Lewy body disease compared to controls. These results are not yet accurate or reliable enough to use as screening tools or isolated diagnostic tests in established disease. It has become clear that factors other than neurodegeneration affect αS concentrations in these tissue samples, such as genetic and environmental influences. Future studies using standardized techniques and larger patient numbers are awaited to realise the full potential of αS as a more definitive diagnostic biomarker.
Tau and p-tau as CSF biomarkers in dementia: a meta-analysis
Authors: van Harten Argonde C. , Kester Maartje I. , Visser Pieter-Jelle , Blankenstein Marinus A. , Pijnenburg Yolande A.L. , van der Flier Wiesje M. , Scheltens Philip
Published: February 2011

Background: To evaluate the value of total tau (tau) and phosphorylated tau (p-tau) in cerebrospinal fluid (CSF) in the differential diagnosis of dementia, more specifically: dementia with Lewy Bodies (DLB), frontotemporal lobar degeneration (FTLD), vascular dementia (VaD), and Creutzfeldt-Jacob disease (CJD).

Methods: A systematic literature search was performed to identify studies on tau and p-tau in DLB, FTLD, VaD and CJD. Tau concentrations were compared to healthy controls and to subjects with Alzheimer's disease (AD) using random effect meta-analysis. Outcome measures were Cohen's delta, sensitivity and specificity.

Results: Compared to controls, tau concentrations are moderately elevated in DLB, FTLD and VaD, while p-tau concentrations are only slightly elevated in DLB and not elevated in FTLD and VaD. Compared to AD, lower tau concentrations differentiated DLB with a sensitivity of 73% and a specificity of 90%, FTLD with sensitivity and specificity of 74%, and VaD with a sensitivity of 73% and a specificity of 86%. Relative to AD, lower p-tau values differentiated FTLD with a sensitivity of 79% and specificity of 83%, and VaD with a sensitivity of 88% and a specificity of 78%. CJD is characterized by extremely elevated tau concentrations with a sensitivity of 91% and a specificity of 98% vs. AD.

Conclusions: CSF tau concentrations in DLB, FTLD and VaD are intermediate between controls and AD patients. Overlap with both controls and AD patients results in insufficient diagnostic accuracy, and the development of more specific biomarkers for these disorders is needed. CJD is characterized by extremely increased tau values, resulting in a sensitivity and specificity that exceeds 90%.
Fire performance of high-strength concrete reinforced with recycled rubber particles
Authors: Li L.-J. , Xie W.-F. , Liu F. , Guo Y.-C. , Deng J.
Published: February 2011

An experimental study was carried out to investigate the fire performance of rubber-reinforced high-strength concrete. The compressive strength and flexural strength after different fire temperatures were investigated. The change in colour of a specimen's appearance was observed and the loss of mass was measured. Scanning electron microscopy micrographs of cementation material after fire were taken in order to explain the mechanism of change of the macrostructure of rubber-reinforced high-strength concrete. The research shows that although the strength of rubber-reinforced high-strength concrete drops slightly after high temperature, its spalling resistance performance is improved greatly. Test results show that the low content (1%) of 15-sieve rubber particles can prevent the high-strength concrete from spalling under fire more efficiently than other rubber content and size options.
Measurement of polarization curve and development of a unique semi empirical model for description of PEMFC and DMFC performances
Authors: Selyari T. , Ghoreyshi A.A. , Shakeri M. , Najafpour G.D. , Jafary T.
Published: February 2011

In this study, a single polymer electrolyte membrane fuel cell (PEMFC) in
H2/O2 form with an effective dimension of 5?5 cm as well as a single direct
methanol fuel cell (DMFC) with a dimension of 10?10 cm were fabricated. In an
existing test station, the voltage-current density performances of the
fabricated PEMFC and DMFC were examined under various operating conditions.
As was expected DMFC showed a lower electrical performance which can be
attributed to the slower methanol oxidation rate in comparison to the
hydrogen oxidation. The results obtained from the cell operation indicated
that the temperature has a great effect on the cell performance. At 60?C, the
best power output was obtained for PEMFC. There was a drop in the cell
voltage beyond 60?C which can be attributed to the reduction of water content
inside the membrane. For DMFC, maximum power output was resulted at 64oC.
Increasing oxygen stoichiometry and total cell pressure had a marginal effect
on the cell performance. The results also revealed that the cell performance
improved by increasing pressure differences between anode and cathode. A
unified semi-empirical thermodynamic based model was developed to describe
the cell voltage as a function of current density for both kinds of fuel
cells. The model equation parameters were obtained through a nonlinear fit to
the experimental data. There was a good agreement between the experimental
data and the model predicted cell performance for both types of fuel cells.
Response surface optimization of medium composition for protease production by Bacillus subtilis using cassava waste
Authors: Rathakrishnan P. , Nagarajan P. , Kannan Rajesh
Published: February 2011

Optimization of the growth condition for maximum growth rate and protease
production was carried out using Bacillus subtilis. The optimization of
protease production using agro industrial waste product such as cassava waste
as substrate was performed with statistical methodology based on experimental
designs. The screening of twelve nutrients for their influence on protease
production was achieved using a Plackett-Burman design. MgSO4.7H2O, casein
and glucose were selected based on their positive influence on protease
production. The selected components were optimized using Response Surface
Methodology (RSM). The optimum conditions are (% w/w): MgsO4.7H2O- 0.14,
casein- 1.4 and glucose- 2.64. These conditions were validated experimentally
which revealed an enhanced protease yield of 202.048 U/gds.
Preterm Diagnosis of Choristoma and Choroidal Coloboma in Goldenhar's Syndrome
Authors: Herwig Martina C. , Gembruch Ulrich , Born Mark , Gevensleben Heidrun , Loeffler Karin U. , Müller Annette M.
Published: February 2011

In addition to general pathological findings characteristic of Goldenhar's syndrome, we report ocular findings in a 22-week-old fetus with hemifacial microsomia, endorsing this diagnosis. After abortion the fetus was examined via a standard paidopathological autopsy including ophthalmopathologic macroscopic and microscopic examination of both eyes. Postmortem findings included left hemifacial microsomia with ipsilateral microtia, atresia of the acoustic meatus, microphthalmia, a ventricular septal defect, and abnormalities of the ribs. Ophthalmopathological examination of the affected microphthalmic eye revealed a scleral choristoma (cartilage), choroidal/retinal pigment epithelium coloboma, and staphyloma. General pathology findings plus the ocular findings allowed the diagnosis of Goldenhar's syndrome. The cartilaginous choristoma present in the patient has previously not been reported in association with this syndrome. A discussion of differential diagnoses is provided, confirming that the ophthalmopathological investigation of fetal eyes can be of great value for classifying syndromes associated with microphthalmia.
Third-Trimester Stillbirths: Correlative Neuropathology and Placental Pathology
Authors: Chang Kenneth T.E. , Keating Sarah , Costa Stacy , Machin Geoffrey , Kingdom John , Shannon Patrick
Published: February 2011

Although in recent years placental pathology has been the subject of a wealth of detailed descriptions and diagnostic categorization, systematic correlation of these conditions with the pathology of stillbirth has not been attempted. We examine the relationship between specific inflammatory, maternal, and fetal vascular pathologies and the central nervous system pathology and histological indicators of fetal compromise. Our design was a retrospective case series of 37 3rd-trimester intrauterine fetal deaths. In general, mixed placental pathologies were the rule, with three quarters of the placentas demonstrating combinations of maternal vascular pathology, fetal vascular pathologies, umbilical cord abnormalities, or inflammatory lesions. The range of brain pathology was limited to acute, severe congestion, white matter edema, and neuronal karyorrhexis (pontosubicular necrosis with or without neuronal karyorrhexis at other sites). Established periventricular leukomalacia was present in only 2 cases. The presence of neuronal karyorrhexis or white matter gliosis was correlated with the presence of a high-grade inflammatory lesion and with fetal thymic involution. Neuronal karyorrhexis, but not white matter gliosis, correlated as well with histologically established fetal vascular lesions in the placenta, even once the effect of inflammation was accounted for. Gliosis also correlated with inflammation, meconium staining, and thymic involution. Central nervous system injury may be the end result of complex placental pathologies, and neuronal injury may be a consequence of the fetal inflammatory response. The correspondence between the time courses of histological features of chorioamnionitis, neuronal karyorrhexis, and thymic involution points to irreversible central nervous system injury being common 12–48 hours prior to in utero demise.
On the core width and Peierls stress of bubble rafts dislocations within the framework of modified Peierls-Nabarro model
Authors: Wu Xiaozhi , Liu Lili , Wang Rui , Ji Na
Published: February 2011

Using Foreman’s method, the core structure and Peierls stress of dislocations in bubble rafts have been investigated within the framework of the modified Peierls-Nabarro (P-N) model in which the discrete lattice effect is taken into account. The core width obtained from the modified P-N model is much wider than that from the P-N model owing to the discrete lattice effect. It is found that the core width of dislocation increases with a decrease of the bubble radius. The elastic strain energy associated with the discrete effect is considered while calculating the Peierls stress. The new expression of the Peierls stress obtained in this paper is not explicitly dependent on the particular form of the restoring force law, which is only related to the core structure parameter and can be used expediently to predict the Peierls stress of dislocations. The Peierls stress decreases rapidly with the decrease of the bubble radius.
Improved and isotropic resolution in tomographic diffractive microscopy combining sample and illumination rotation
Authors: Vertu Stanislas , Flügge Jens , Delaunay Jean-Jacques , Haeberlé Olivier
Published: February 2011

Tomographic Diffractive Microscopy is a technique, which permits to image transparent living specimens in three dimensions without staining. It is commonly implemented in two configurations, by either rotating the sample illumination keeping the specimen fixed, or by rotating the sample using a fixed illumination. Under the first-order Born approximation, the volume of the frequency domain that can be mapped with the rotating illumination method has the shape of a “doughnut”, which exhibits a so-called “missing cone” of non-captured frequencies, responsible for the strong resolution anisotropy characteristic of transmission microscopes. When rotating the sample, the resolution is almost isotropic, but the set of captured frequencies still exhibits a missing part, the shape of which resembles that of an apple core. Furthermore, its maximal extension is reduced compared to tomography with rotating illumination. We propose various configurations for tomographic diffractive microscopy, which combine both approaches, and aim at obtaining a high and isotropic resolution. We illustrate with simulations the expected imaging performances of these configurations.
Family Treasures: A Dual-Language Book Project for Negotiating Language, Literacy, Culture, and Identity
Authors: Roessingh Hetty
Published: February 2011

This article advances a framework for early language and literacy development among young English language learners (ELLs). A dual-language book project undertaken in partnership with a local elementary school provides a context within which to address children's need to negotiate language, culture, and identity as they transition and make meaning from their home language (L1) to English and the language of school (L2) and back. Using objects of cultural and personal relevance that the children brought from home, stories of ‘Family Treasures’ were generated from the original telling in the L1 into English in small-group contexts, transcribed, illustrated, and uploaded to a Web site for permanent sharing, rereading, and exchange. These booklets also provided an opportunity for identity formation, pride of family and culture, and the acquisition of rudimentary technology skills, which all work to motivate and engage young learners in the development of early literacy.
Quantitative evaluation of movement and strength of the upper limb after transection of the C-7 nerve: is it possible in an animal model?
Authors: Wang Huan , Spinner Robert J. , Windebank Anthony J.
Published: February 2011

Object

Contralateral C-7 nerve transfer has been used clinically for more than 20 years. The increased interest in studies of transfer effectiveness at different target muscles, posttransfer cocontraction, and brain plasticity has prompted the need for an animal model. In addition to the conventional electrophysiological, histomorphometric, and biomechanical evaluation modalities, quantitative functional and behavioral evaluation will be crucial in applying this kind of model. The aim of this study was to establish a C-7 transection animal model and quantify the changes in upper-limb joint movement and muscle power.

Methods

A C-7 nerve transection model was created in Sprague-Dawley rats, the brachial plexus of which resembles the human brachial plexus. The impact of C-7 transection on donor limb function—namely, strength, movement, and coordination—was evaluated in 6 rats. Muscle strength (power reported in g) was measured as a grasping task. The active range of motion (ROM; angle reported in °) of the elbow, wrist, and metacarpophalangeal joints was quantified by computerized video motion analysis. Antiresistance coordinated movement (speed reported in seconds) was assessed by the vertical rope-climbing test. These tests were carried out before surgery and at 2, 4, 6, 8, 10, 14, 21, and 28 days after C-7 transection. Repeated-measures 1-way analysis of variance was applied for statistical analysis. When the overall probability value was < 0.05, the Dunnett multiple-comparison posttest was used to compare postoperative values with preoperative baseline values.

Results

Immediately after C-7 transection, the mean ± SD grip strength declined from 378.50 ± 20.55 g to 297.77 ± 15.04 g. Active elbow extension was impaired, as shown by a significant decrease of the elbow extension angle. The speed of vertical rope climbing was also reduced. Elbow flexion, wrist flexion and extension, and metacarpophalangeal joint flexion and extension were not impaired. Fast recovery of motor function was observed thereafter. Grip strength, range of active elbow extension, and speed of rope climbing returned to baseline values at postoperative Days 4, 8, and 8, respectively.

Conclusions

The ROM and muscle strength of the upper limb in rats can be measured quantitatively in studies that simulate clinical situations. Application of these functional evaluation modalities in a C-7 nerve transection rat model confirmed that transection of C-7 causes only temporary functional dysfunction to the donor limb. The results obtained in this animal model mimic those seen in humans who undergo contralateral C-7 nerve harvesting.
Biomechanical rigidity of cadaveric cervical spine with posterior versus combined posterior and anterior instrumentation
Authors: Dahdaleh Nader S. , Nakamura Satoshi , Torner James C. , Lim Tae-Hong , Hitchon Patrick W.
Published: February 2011

Object

In patients with cervical stenosis with myelopathy, posterior instrumentation following cervical laminectomy has been shown to reduce the incidence of postoperative instability and kyphosis. However, the indications for posterior plus anterior instrumentation are not always obvious, and using both posterior and anterior instrumentation routinely is unnecessary and excessive. This study examines the rigidity of the intact isolated cadaveric cervical spine, after C4–6 laminectomy, with posterior lateral mass instrumentation, and following posterior plus anterior instrumentation.

Methods

Ten fresh-frozen human cadaveric cervical spines from C-1 to T-2 were potted in the neutral position, and retroreflective markers were placed on C-3 and C-7. Specimens were mounted on a biomechanical testing frame, and angular rotations of C-3 relative to C-7 were measured. Pure moments of 0, 0.3, 0.6, 0.9, and 1.2 Nm were applied at C-2 in all 3 planes. Each specimen was load tested as follows: 1) in the intact state; 2) after C4–6 laminectomy; 3) with C3–7 lateral mass instrumentation; and 4) with C3–7 posterior plus anterior instrumentation.

Results

Laminectomy was not associated with a significant increase in motion compared with the intact state with any load or in any direction. Instrumentation was associated with reduction in motion in all directions, and there was no significant difference in posterior versus combined posterior and anterior instrumentation.

Conclusions

Rigidity imparted to the cervical spine by a 5-level posterior lateral mass fixation is not augmented by anterior instrumentation.
Clinical and radiographic outcomes of pedicle screw fixation for upper thoracic spine (T1–5) fractures: a retrospective cohort study of 27 cases
Authors: Fisher Charles , Singh Sandeep , Boyd Michael , Kingwell Stephen , Kwon Brian , Li Meng Jun , Dvorak Marcel
Published: February 2011

Object

The use of pedicle screws (PSs) for stabilization of unstable thoracolumbar fractures has become the standard of care, but PS efficacy has not been reported in the upper thoracic spine. The primary outcome of this study was to determine the efficacy of PS fixation to achieve and maintain reduction of unstable upper thoracic spine fractures (T1–5). Secondary outcomes included scores on a 1-year postoperative generic health-related quality of life (QOL) questionnaire and postoperative complications.

Methods

This study was a retrospective analysis and cross-sectional outcome assessment of cases prospectively entered into a spine database from 1997 to 2004. All patients with a traumatic, unstable upper thoracic spine (T1–5) fracture who underwent PS fixation were included. Preoperative CT scans with sagittal plane reformatted images were used to determine kyphotic deformity and compared with immediate postoperative and latest follow-up radiographs or CT scans. Patient charts, operative notes, and the results of postoperative follow-up examinations were reviewed. Patients were mailed the Short Form-36v2 (SF-36 version 2) by an independent study coordinator.

Results

Cases involving 27 patients (23 male, 4 female) were evaluated. The patients' mean age was 39.9 years (range 16–73 years). In all, 251 PSs were passed between T-1 and T-8. The mean true kyphotic deformity was 18.2° preoperatively, 8.7° (p < 0.0005) initially postoperatively, and 10.1° at final follow-up (mean 2.3 years postoperatively). The mean SF-36 physical component summary score was 35.89 while the mental component summary score was 56.43 at a minimum of 1-year postoperatively (mean 3.2 years). There were no intraoperative vascular or neural complications.

Conclusions

In the hands of fellowship-trained spinal surgeons, PS fixation for reduction and stabilization of upper thoracic spine fractures is a safe and efficacious technique. Health-related QOL outcome data are deficient for spine trauma patients and should be an essential component of quantifying treatment outcomes.
The natural history of cervical spondylotic myelopathy
Authors: Matz Paul G. , Anderson Paul A. , Holly Langston T. , Groff Michael W. , Heary Robert F. , Kaiser Michael G. , Mummaneni Praveen V. , Ryken Timothy C. , Choudhri Tanvir F. , Vresilovic Edward J. , Resnick Daniel K.
Published: February 2011

Object

The objective of this systematic review was to use evidence-based medicine to delineate the natural history of cervical spondylotic myelopathy (CSM) and identify factors associated with clinical deterioration.

Methods

The National Library of Medicine and Cochrane Database were queried using MeSH headings and keywords relevant to the natural history of CSM. Abstracts were reviewed and studies meeting the inclusion criteria were selected. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Classes I–III). Disagreements regarding the level of evidence were resolved through an expert consensus conference. The group formulated recommendations that contained the degree of strength based on the Scottish Intercollegiate Guidelines network. Validation was done through peer review by the Joint Guidelines Committee of the American Association of Neurological Surgeons and the Congress of Neurological Surgeons.

Results

The natural history of CSM is mixed: it may manifest as a slow, stepwise decline or there may be a long period of quiescence (Class III). Long periods of severe stenosis are associated with demyelination and may result in necrosis of both gray and white matter. With severe and/or long lasting CSM symptoms, the likelihood of improvement with nonoperative measures is low. Objectively measurable deterioration is rarely seen acutely in patients younger than 75 years of age with mild CSM (modified Japanese Orthopaedic Association scale score > 12; Class I). In patients with cervical stenosis without myelopathy, the presence of abnormal electromyography findings or the presence of clinical radiculopathy is associated with the development of symptomatic CSM in this patient population (Class I).

Conclusions

The natural history of CSM is variable, which may affect treatment decisions.
Cervical cord compression due to delayed scarring around epidural electrodes used in spinal cord stimulation
Authors: Dam-Hieu Phong , Magro Elsa , Seizeur Romuald , Simon Alexandre , Quinio Bertrand
Published: February 2011

The authors report on 2 cases of delayed compression of the cervical spinal cord by dense scar tissue forming around epidural electrodes implanted for spinal cord stimulation (SCS). This complication has not been previously reported.

Myelopathy developed in 2 patients 5 and 16 years after the surgical placement of a cervical epidural electrode. Prior to myelopathy, both patients experienced a tolerance phenomenon. Magnetic resonance imaging in both cases showed severe compression of the spinal cord by the electrode. At surgery, thick scar tissue surrounding the electrode and compressing the posterior aspect of the cord was discovered. Both patients experienced a full recovery following the removal of both scar tissue and the electrode.

Medical and paramedical staff dealing with SCS should be aware of this severe and delayed complication. In addition, the development of epidural fibrosis can explain the occurrence of tolerance.
A unique device, the disc space–fitted distraction device, for anterior cervical discectomy and fusion: early clinical and radiological evaluation
Authors: Tani Satoshi , Nagashima Hiroyasu , Isoshima Akira , Akiyama Masahiko , Ohashi Hiroki , Tochigi Satoru , Abe Toshiaki
Published: February 2011

Object

To perform interbody distraction and to obtain spinal curvature correction during anterior cervical discectomy and fusion (ACDF), the authors recently adopted a new stand-alone device, a disc space–fitted distraction device (DFDD). In this preliminary report the authors introduce this unique device and discuss some advantages in terms of short-term clinical and radiological evaluations.

Methods

The most unique aspect of the DFDD is the function of gentle distraction at anterior disc space with maximum lordotic correction of up to 8° while rotating a screw at the front of the device. Additional advantages are related to its configuration such as disc space–matched shape in all dimensions, tapering contour for easy insertion into the disc space, multiple spikes to avoid dislodgment, wider contact area to the vertebral endplate for diminishing sinking process, and sufficient space for accommodation of bone-conductive materials. Twenty-four patients who have been observed more than 12 months after ACDF were involved in this evaluation.

Results

The objective clinical outcome, measured by the Neurological Cervical Spine Scale, was significantly improved. In radiological evaluation, statistically significant improvement compared with preoperative values was noted on the curvature index, C2–7 curvature, and disc angle (p < 0.01) throughout the entire postoperative period, up to 12 months. A high fusion rate and remodeling process around the implants were also observed.

Conclusions

The DFDD may have some advantages over other devices—its distraction action, diminished sinking, and early solid bone union resulted in maintaining sufficient correction of the spinal curvature. This corrected spinal curvature may play an important role in preventing progressive adjacent-disc degeneration subsequent to ACDF in the long term.
A computed tomography–based feasibility study of translaminar screw fixation in the upper thoracic spine
Authors: Kretzer Ryan M. , Chaput Christopher , Sciubba Daniel M. , Garonzik Ira M. , Jallo George I. , McAfee Paul C. , Cunningham Bryan W. , Tortolani P. Justin
Published: February 2011

Object

Translaminar screws (TLSs) offer an alternative to pedicle screw (PS) fixation in the upper thoracic spine. Although cadaveric studies have described the anatomy of the laminae and pedicles at T1–2, CT imaging is the modality of choice for presurgical planning. In this study, the goal was to determine the diameter, maximal screw length, and optimal screw trajectory for TLS placement at T1–2, and to compare this information to PS placement in the upper thoracic spine as determined by CT evaluation.

Methods

One hundred patients (50 men and 50 women), whose average age was 41.7 ± 19.6 years, were selected by retrospective review of a trauma registry database over a 6-month period. Patients were included in the study if they were over the age of 18, had standardized axial bone-window CT imaging at T1–2, and had no evidence of spinal trauma. For each lamina and pedicle, width (outer cortical and cancellous), maximal screw length, and optimal screw trajectory were measured using eFilm Lite software. Statistical analysis was performed using the Student t-test.

Results

The T-1 lamina was estimated to accommodate, on average, a 5.8-mm longer screw than the T-2 lamina (p < 0.001). At T-1, the maximal TLS length was similar to PS length (TLS: 33.4 ± 3.6 mm, PS: 33.9 ± 3.3 mm [p = 0.148]), whereas at T-2, the maximal PS length was significantly greater than the TLS length (TLS: 27.6 ± 3.1 mm, PS: 35.3 ± 3.5 mm [p < 0.001]). When the lamina outer cortical and cancellous width was compared between T-1 and T-2, the lamina at T-2 was, on average, 0.3 mm wider than at T-1 (p = 0.007 and p = 0.003, respectively). In comparison with the corresponding pedicle, the mean outer cortical pedicle width at T-1 was wider than the lamina by an average of 1.0 mm (lamina: 6.6 ± 1.1 mm, pedicle: 7.6 ± 1.3 mm [p < 0.001]). At T-2, however, outer cortical lamina width was wider than the corresponding pedicle by an average of 0.6 mm (lamina: 6.9 ± 1.1 mm, pedicle: 6.3 ± 1.2 mm [p < 0.001]). At T-1, 97.5% of laminae measured could accept a 4.0-mm screw with 1.0 mm of clearance, compared with 99.5% of T-1 pedicles; whereas at T-2, 99% of laminae met this requirement, compared with 94.5% of pedicles. The ideal screw trajectory was also measured (T-1: 49.2 ± 3.7° for TLS and 32.8 ± 3.8° for PS; T-2: 51.1 ± 3.5° for TLS and 20.5 ± 4.4° for PS).

Conclusions

Based on CT evaluation, there are no anatomical limitations to the placement of TLSs compared with PSs at T1–2. Differences were noted, however, in lamina length and width between T-1 and T-2 that must be considered when placing TLS at these levels.
Management of anterior cervical pseudarthrosis
Authors: Kaiser Michael G. , Mummaneni Praveen V. , Matz Paul G. , Anderson Paul A. , Groff Michael W. , Heary Robert F. , Holly Langston T. , Ryken Timothy C. , Choudhri Tanvir F. , Vresilovic Edward J. , Resnick Daniel K.
Published: February 2011

Object

The objective of this systematic review was to use evidence-based medicine to identify the best methodology for diagnosis and treatment of anterior pseudarthrosis.

Methods

The National Library of Medicine and Cochrane Database were queried using MeSH headings and key words relevant to pseudarthrosis and cervical spine surgery. Abstracts were reviewed, after which studies meeting inclusion criteria were selected. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Classes I–III). Disagreements regarding the level of evidence were resolved through an expert consensus conference. The group formulated recommendations that contained the degree of strength based on the Scottish Intercollegiate Guidelines network. Validation was done through peer review by the Joint Guidelines Committee of the American Association of Neurological Surgeons/Congress of Neurological Surgeons.

Results

Evaluation for pseudarthrosis is warranted, as there may be an association between clinical outcome and pseudarthrosis. The strength of this association cannot be accurately determined because of the variable incidence of symptomatic and asymptomatic pseudarthroses (Class III). Revision of a symptomatic pseudarthrosis may be considered because arthrodesis is associated with improved clinical outcome (Class III). Both posterior and anterior approaches have proven successful for surgical correction of an anterior pseudarthrosis. Posterior approaches may be associated with higher fusion rates following repair of an anterior pseudarthrosis (Class III).

Conclusions

If suspected, pseudarthrosis should be investigated because there may be an association between arthrodesis and outcome. However, the strength of this association cannot be accurately determined. Anterior and posterior approaches have been successful.
Indications for anterior cervical decompression for the treatment of cervical degenerative radiculopathy
Authors: Matz Paul G. , Holly Langston T. , Groff Michael W. , Vresilovic Edward J. , Anderson Paul A. , Heary Robert F. , Kaiser Michael G. , Mummaneni Praveen V. , Ryken Timothy C. , Choudhri Tanvir F. , Resnick Daniel K.
Published: February 2011

Object

The objective of this systematic review was to use evidence-based medicine to identify the indications and utility of anterior cervical nerve root decompression.

Methods

The National Library of Medicine and Cochrane Database were queried using MeSH headings and key words relevant to surgical management of cervical radiculopathy. Abstracts were reviewed after which studies meeting inclusion criteria were selected. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Classes I–III). Disagreements regarding the level of evidence were resolved through an expert consensus conference. The group formulated recommendations that contained the degree of strength based on the Scottish Intercollegiate Guidelines network. Validation was done through peer review by the Joint Guidelines Committee of the American Association of Neurological Surgeons/Congress of Neurological Surgeons.

Results

Anterior nerve root decompression via anterior cervical discectomy (ACD) with or without fusion for radiculopathy is associated with rapid relief (3–4 months) of arm/neck pain, weakness, and/or sensory loss compared with physical therapy (PT) or cervical collar immobilization. Anterior cervical discectomy and ACD with fusion (ACDF) are associated with longer term (12 months) improvement in certain motor functions compared to PT. Other rapid gains observed after anterior decompression (diminished pain, improved sensation, and improved strength in certain muscle groups) are also maintained over the course of 12 months. However, comparable clinical improvements with PT or cervical immobilization therapy are also present in these clinical modalities (Class I). Conflicting evidence exists as to the efficacy of anterior cervical foraminotomy with reported success rates of 52–99% but recurrent symptoms as high as 30% (Class III).

Conclusions

Anterior cervical discectomy, ACDF, and anterior cervical foraminotomy may improve cervical radicular symptoms. With regard to ACD and ACDF compared to PT or cervical immobilization, more rapid relief (within 3–4 months) may be seen with ACD or ACDF with maintenance of gains over the course of 12 months (Class I). Anterior cervical foraminotomy is associated with improvement in clinical function but the quality of data are weaker (Class III), and there is a wide range of efficacy (52–99%).
The major complications of transpedicular vertebroplasty
Authors: Cosar Murat , Sasani Mehdi , Oktenoglu Tunc , Kaner Tuncay , Ercelen Omur , Kose K. Cagri , Ozer A. Fahir
Published: February 2011

Object

Vertebroplasty is a well-known technique used to treat pain associated with vertebral compression fractures. Despite a success rate of up to 90% in different series, the procedure is often associated with major complications such as cord and root compression, epidural and subdural hematomas (SDHs), and pulmonary emboli, as well as other minor complications. In this study, the authors discuss the major complications of transpedicular vertebroplasty and their clinical implications during the postoperative course.

Methods

Vertebroplasty was performed in 12 vertebrae of 7 patients. Five patients had osteoporotic compression fractures, 1 had tumoral compression fractures, and 1 had a traumatic fracture. Two patients had foraminal leakage, 1 had epidural leakage, 1 had subdural cement leakage, 2 had a spinal SDH, and the last had a split fracture after the procedure.

Results

Three patients had paraparesis (2 had SDHs and 1 had epidural cement leakage), 3 had root symptoms, and 1 had lower back pain. Two of the 3 patients with paraparesis recovered after evacuation of the SDH and subdural cement; however, 1 patient with paraparesis did not recover after epidural cement leakage, despite cement evacuation. Two patients with foraminal leakage and 1 with subdural cement leakage had root symptoms and recovered after evacuation and conservative treatment. The patient with the split fracture had no neurological symptoms and recovered with conservative treatment.

Conclusions

Transpedicular vertebroplasty may have major complications, such as a spinal SDH and/or cement leakage into the epidural and subdural spaces, even when performed by experienced spinal surgeons. Early diagnosis with CT and intervention may prevent worsening of these complications.
Posttraumatic spinal cord tethering and syringomyelia: surgical treatment and long-term outcome
Authors: Falci Scott P. , Indeck Charlotte , Lammertse Daniel P.
Published: February 2011

Object

Permanent neurological loss after spinal cord injury (SCI) is a well-known phenomenon. There has also been a growing recognition and improved understanding of the pathophysiological mechanisms of late progressive neurological loss, which may occur after SCI as a result of posttraumatic spinal cord tethering (SCT), myelomalacia, and syringomyelia. A clinical study of 404 patients sustaining traumatic SCIs and undergoing surgery to arrest a progressive myelopathy caused by SCT, with or without progressive myelomalacia and cystic cavitation (syringomyelia) was undertaken. Both objective and subjective long-term outcomes were evaluated. To the authors' knowledge, this is the first series of this size correlating long-term patient perception of outcome with long-term objective outcome analyses.

Methods

During the period from January 1993 to November 2003, 404 patients who had previously sustained traumatic SCIs underwent 468 surgeries for progressive myelopathies attributed to tethering of the spinal cord to the surrounding spinal canal, with or without myelomalacia and syrinx formation. Forty-two patients were excluded because of additional pathological entities that were known to contribute to a progressive myelopathy. All surgeries were performed by the same neurosurgeon at a single SCI treatment center and by using a consistent surgical technique of spinal cord detethering, expansion duraplasty, and when indicated, cyst shunting.

Results

Outcome data were collected up to 12 years postoperatively. Comparisons of pre- and postoperative American Spinal Injury Association sensory and motor index scores showed no significant change when only a single surgery was required (86% of patients). An outcome questionnaire and phone interview resulted in > 90% of patients self-assessing arrest of functional loss; > 50% of patients self-assessing improvement of function; 17 and 18% self-assessing improvement of motor and sensory functions to a point greater than that achieved at any time postinjury, respectively; 59% reporting improvement of spasticity; and 77% reporting improvement of hyperhidrosis.

Conclusions

Surgery for spinal cord detethering, expansion duraplasty, and when indicated, cyst shunting, is a successful treatment strategy for arresting a progressive myelopathy related to posttraumatic SCT and syringomyelia. Results suggest that surgery leads to functional return in ~ 50% of patients, and that in some patients posttraumatic SCT limits maximal recovery of spinal cord function postinjury. A patient's perception of surgery's failure to arrest the progressive myelopathy corresponds closely with the need for repeat surgery because of retethering, cyst reexpansion, and pseudomeningocele formation.
Use of allograft bone for posterior C1–2 fusion
Authors: Hillard Virany Huynh , Fassett Daniel R. , Finn Michael A. , Apfelbaum Ronald I.
Published: February 2011

Object

An iliac crest autograft is the gold standard for bone grafting in posterior atlantoaxial arthrodesis but can be associated with significant donor-site morbidity. Conversely, an allograft has historically performed suboptimally for atlantoaxial arthrodesis as an onlay graft. The authors have modified a bone grafting technique to allow placement of a bicortical iliac crest allograft in an interpositional manner, and they evaluated it as an alternative to an autograft in posterior atlantoaxial arthrodesis.

Methods

The records of 89 consecutive patients in whom C1–2 arthrodesis was performed between 2001 and 2005 were reviewed.

Results

Forty-seven patients underwent 48 atlantoaxial arthrodeses with an allograft (mean follow-up 16.1 months, range 0–49 months), and 42 patients underwent autograft bone grafting (mean follow-up 17.6 months, range 0–61.0 months). The operative time was 50 minutes shorter in the allograft (mean 184 minutes, range 106–328 minutes) than in the autograft procedure (mean 234 minutes, range 154–358 minutes), and the estimated blood loss was 50% lower in the allograft group than in the autograft group (mean 103 ml [range 30–200 ml] vs mean 206 ml [range 50–400 ml], respectively). Bone incorporation was initially slower in the allograft than in the autograft group but equalized by 12 months postprocedure. The respective fusion rates after 24 months were 96.7 and 88.9% for autografts and allografts. Complications at the donor site occurred in 16.7% of the autograft patients, including 1 pelvic fracture, 1 retained sponge, 1 infection, 2 hernias requiring repair, 2 hematomas, and persistent pain.

Conclusions

The authors describe a technique for interpositional bone grafting between C-1 and C-2 that allows for the use of an allograft with excellent fusion results. This technique reduced the operative time and blood loss and eliminated donor-site morbidity.
Factors associated with pressure ulcers in patients with complete or sensory-only preserved spinal cord injury: is there any difference between traumatic and nontraumatic causes?
Authors: Taghipoor Keyvan Davatgaran , Arejan Roya Habibi , Rasouli Mohammad Reza , Saadat Soheil , Moghadam Mojgan , Vaccaro Alexander R. , Rahimi-Movaghar Vafa
Published: February 2011

Object

Pressure ulcers (PUs) are common complications in patients with complete spinal cord injury (SCI) or incomplete SCI in which sensory function is spared. Most studies analyzing associated factors of PU and SCI have been performed in cases of traumatic SCI and in just a few cases of nontraumatic SCI. This study was designed to look specifically at the differences in causative factors of PU in cases of traumatic and nontraumatic SCIs.

Methods

The authors performed a retrospective, cross-sectional study evaluating patients with complete and incomplete SCIs (American Spinal Injury Association Grades A and B) under the coverage of the financial, medicosocial, and rehabilitative support provided by the State Welfare Organization of Iran (SWOI). There were 3791 cases of traumatic SCI (63.2%) and 2110 cases of nontraumatic SCI (35.2%). For 94 patients (1.6%), sufficient data were not available.

Results

A PU was detected in 39.2% of all patients with an SCI (71.8% of those with traumatic SCI vs 28.2% of those with nontraumatic SCI). A univariate analysis showed a significant association between occupation, education, and the presence of PU in patients with a traumatic SCI (p < 0.05). This contrasted with nontraumatic SCI in which an association between PU and age was noted (p < 0.05).

Using logistic regression, traumatic cause, older age, an interval less than 1 year since the onset of SCI, male sex, and single status were found to significantly increase the risk of PU in all patients with an SCI. However, a higher education level had a preventive effect on PU.

Conclusions

This study revealed some risk factors for PU in the authors' setting. The authors' findings suggest a possible difference between the risk factors for PU in patients with both types of SCI. Further study on the pathoetiology of these differences is paramount in the future.