18 research outputs found

    Optimal surgical care for adolescent idiopathic scoliosis: an international consensus

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    Purpose The surgical management of adolescent idiopathic scoliosis (AIS) has seen many developments in the last two decades. Little high-level evidence is available to support these changes and guide treatment. This study aimed to identify optimal operative care for adolescents with AIS curves between 40° and 90° Cobb angle. Methods From July 2012 to April 2013, the AOSpine Knowledge Forum Deformity performed a modified Delphi survey where current expert opinion from 48 experienced deformity surgeons, representing 29 diverse countries, was gathered. Four rounds were performed: three web-based surveys and a final face-to-face meeting. Consensus was achieved with ≄70 % agreement. Data were analyzed qualitatively and quantitatively. Results Consensus of what constitutes optimal care was reached on greater than 60 aspects including: preoperative radiographs; posterior as opposed to anterior (endoscopic) surgical approaches; use of intraoperative spinal cord monitoring; use of local autologous bone (not iliac crest) for grafts; use of thoracic and lumbar pedicle screws; use of titanium anchor points; implant density of <80 % for 40°–70° curves; and aspects of postoperative care. Variability in practice patterns was found where there was no consensus. In addition, there was consensus on what does not constitute optimal care, including: routine pre- and intraoperative traction; routine anterior release; use of bone morphogenetic proteins; and routine postoperative CT scanning. Conclusions International consensus was found on many aspects of what does and does not constitute optimal operative care for adolescents with AIS. In the absence of current high-level evidence, at present, these expert opinion findings will aid health care providers worldwide define appropriate care in their regions. Areas with no consensus provide excellent insight and priorities for future researchpublished_or_final_versio

    News from the Muon (g-2) Experiment at BNL

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    The magnetic moment anomaly a_mu = (g_mu - 2) / 2 of the positive muon has been measured at the Brookhaven Alternating Gradient Synchrotron with an uncertainty of 0.7 ppm. The new result, based on data taken in 2000, agrees well with previous measurements. Standard Model evaluations currently differ from the experimental result by 1.6 to 3.0 standard deviations.Comment: Talk presented at RADCOR - Loops and Legs 2002, Kloster Banz, Germany, September 8-13 2002, to be published in Nuclear Physics B (Proc. Suppl.); 5 pages, 3 figure

    Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm

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    We present the first results of the Fermilab Muon g-2 Experiment for the positive muon magnetic anomaly aÎŒâ‰Ą(gΌ−2)/2a_\mu \equiv (g_\mu-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ωa\omega_a between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω~pâ€Č{\tilde{\omega}'^{}_p} in a spherical water sample at 34.7∘^{\circ}C. The ratio ωa/ω~pâ€Č\omega_a / {\tilde{\omega}'^{}_p}, together with known fundamental constants, determines aÎŒ(FNAL)=116 592 040(54)×10−11a_\mu({\rm FNAL}) = 116\,592\,040(54)\times 10^{-11} (0.46\,ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both ÎŒ+\mu^+ and Ό−\mu^-, the new experimental average of aÎŒ(Exp)=116 592 061(41)×10−11a_\mu({\rm Exp}) = 116\,592\,061(41)\times 10^{-11} (0.35\,ppm) increases the tension between experiment and theory to 4.2 standard deviationsComment: 10 pages; 4 figure

    Measuring outcomes in adult spinal deformity surgery: a systematic review to identify current strengths, weaknesses and gaps in patient-reported outcome measures

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    Contains fulltext : 176886.pdf (Publisher’s version ) (Open Access)PURPOSE: Adult spinal deformity (ASD) causes severe disability, reduces overall quality of life, and results in a substantial societal burden of disease. As healthcare is becoming more value based, and to facilitate global benchmarking, it is critical to identify and standardize patient-reported outcome measures (PROMs). This study aims to identify the current strengths, weaknesses, and gaps in PROMs used for ASD. METHODS: Studies were included following a systematic search in multiple bibliographic databases between 2000 and 2015. PROMs were extracted and linked to the outcome domains of WHO's International Classification of Functioning and Health (ICF) framework. Subsequently, the clinimetric quality of identified PROMs was evaluated. RESULTS: The literature search identified 144 papers that met the inclusion criteria, and nine frequently used PROMs were identified. These covered 29 ICF outcome domains, which could be grouped into three of the four main ICF chapters: body function (n = 7), activity and participation (n = 19), environmental factors (n = 3), and body structure (n = 0). A low quantity (n = 3) of papers was identified that studied the clinimetric quality of PROMs. The Scoliosis Research Society (SRS)-22 has the highest level of clinimetric quality for ASD. CONCLUSIONS: Outcome domains related to mobility and pain were well represented. We identified a gap in current outcome measures regarding neurological and pulmonary function. In addition, no outcome domains were measured in the ICF chapter body structure. These results will serve as a foundation for the process of seeking international consensus on a standard set of outcome domains, accompanied PROMs and contributing factors to be used in future clinical trials and spine registries

    Light-weight flexible magnetic shields for large-aperture photomultiplier tubes

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    Thin flexible sheets of high-permeability FINEMETŸ foils encased in thin plastic layers have been used to shield various types of 20-cm-diameter photomultiplier tubes from ambient magnetic fields. In the presence of the Earth's magnetic field this type of shielding is shown to increase the collection efficiency of photoelectrons and can improve the uniformity of response of these photomultiplier tubes. © 2013 Elsevier B.V

    Integrative science in practice : Process perspectives from ASB, the partnership for the tropical forest margins

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    ASB, the Partnership for the Tropical Forest Margins, is a decade-old, complex, multi-institutional, multi-disciplinary, multi-site research and development consortium. It has been recognized for its success in producing scientific outputs and real world impacts and as a pioneer in integrated natural resource management (iNRM). Until now, there has been little understanding of the reasons for its success in integrating different perspectives and ways of working. To fill this gap, an on-line consultation involving ASB researchers was structured following an analytical framework developed by the Initiative on Science and Technology for Sustainability. The structure of the presentation of major results presented in this article also follows that framework, which includes four dimensions of integration (disciplinary, functional, spatial/temporal, and knowledge) and linked challenges of institutional learning and adaptation, fostering appropriate participation, and managing resource and capacity constraints. To lay the foundations for interpreting these insights and to motivate the study, introductory sections present qualitative evidence regarding organizational learning within the consortium (using research hypotheses as indicators) and success in producing integrated results (using a selection of research results as evidence). This report on ASB's experience in integrative science and organizational learning is intended to advance understanding of the scope and limits of a complex international consortium to integrate activities across disciplines, organizations, scales and knowledge systems in order to produce knowledge and policy relevant outputs. ASB's processes and structures have weaknesses as well as strengths. And while there almost certainly are a range of effective alternative approaches to integrative science, the insights from ASB's experience documented in these online discussions could be of interest to other geographically dispersed teams, especially those working on environment and development issues. Moreover, from a methodological perspective, the use of information technology reported in this article proved to be an effective means of triangulating the perceptions of geographically dispersed researchers. In doing so, this web-based consultation provided a medium for reflection by a large ‘virtual team’ on whether words about integration are translated into practice, at least as perceived and self-reported by the scientists who participated. These techniques could be employed for process documentation by other dispersed teams, thereby adding to the stock of information on what works (and what does not) in efforts to put integrative science into practice on a significant scale

    Responding to Intraoperative Neuromonitoring Changes During Pediatric Coronal Spinal Deformity Surgery

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    Contains fulltext : 208126.pdf (publisher's version ) (Open Access)Study Design: Retrospective case study on prospectively collected data. Objectives: The purpose of this explorative study was: 1) to determine if patterns of spinal cord injury could be detected through intra-operative neuromonitoring (IONM) changes in pediatric patients undergoing spinal deformity corrections, 2) to identify if perfusion based or direct trauma causes of IONM changes could be distinguished, 3) to observe the effects of the interventions performed in response to these events, and 4) to attempt to identify different treatment algorithms for the different causes of IONM alerts. Methods: Prospectively collected neuromonitoring data in pre-established forms on consecutive pediatric patients undergoing coronal spinal deformity surgery at a single center was reviewed. Real-time data was collected on IONM alerts with >50% loss in signal. Patients with alerts were divided into 2 groups: unilateral changes (direct cord trauma), and bilateral MEP changes (cord perfusion deficits). Results: A total of 97 pediatric patients involving 71 females and 26 males with a mean age of 14.9 (11-18) years were included in this study. There were 39 alerts in 27 patients (27.8% overall incidence). All bilateral changes responded to a combination of transfusion, increasing blood pressure, and rod removal. Unilateral changes as a result of direct trauma, mainly during laminotomies for osteotomies, improved with removal of the causative agent. Following corrective actions in response to the alerts, all cases were completed as planned. Signal returned to near baseline in 20/27 patients at closure, with no new neurological deficits in this series. Conclusion: A high incidence of alerts occurred in this series of cases. Dividing IONM changes into perfusion-based vs direct trauma directed treatment to the offending cause, allowing for safe corrections of the deformities. Patients did not need to recover IONM signal to baseline to have a normal neurological examination
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