Реверсивное эндопротезирование плечевого сустава после оскольчатого перелома плечевой кости: клинический случай

Background. Fractures of the proximal humerus are common injury, especially among older age group patients. For the treatment of most cases, conservative tactics are required, some require surgery: osteosynthesis, arthroplasty. Proximal humerus fractures with extension to the metadiaphyseal and diaphyseal zones uncommon, and treatment of this type of injuries is complex for trauma surgeons. The aim of the study is to demonstrate successful experience of two-stage treatment of the proximal humerus fracture with extension to the diaphysis middle third in an older age group patient. Case presentation. The clinical case presents successful two-stage treatment of the proximal humerus fracture with extension to the middle third of the diaphysis in an older age group patient. The first stage was performed osteosynthesis of the humerus with the PHILOS Long plate, the second stage reverse shoulder arthroplasty. Conclusion. Consistent performing of osteosynthesis and total reverse shoulder arthroplasty allows to achieve satisfactory treatment results with restoration of the injured limb function and relief of pain syndrome.Актуальность. Переломы проксимального отдела плечевой кости распространенная травма, особенно среди пациентов старшей возрастной группы. Для лечения большинства данных повреждений применяется консервативная тактика, однако некоторым пациентам требуется хирургическое лечение: остеосинтез, эндопротезирование. Переломы проксимального отдела плечевой кости с распространением на метадиафизарную и диафизарную зоны встречаются значительно реже, и их лечение представляет сложную задачу для травматологов. Описание случая. Представлен успешный опыт двухэтапного лечения перелома проксимального отдела плечевой кости с распространением до средней трети диафиза у пациентки старшей возрастной группы. Первым этапом выполнен остеосинтез плечевой кости пластиной PHILOS Long, вторым этапом реверсивное эндопротезирование плечевого сустава. Заключение. Последовательное применение остеосинтеза и тотального реверсивного эндопротезирования плечевого сустава позволяет добиться удовлетворительных результатов лечения с восстановлением функции травмированной конечности и купированием болевого синдрома

Rotating membranes on G_2 manifolds, logarithmic anomalous dimensions and N=1 duality

We show that the $E-S \sim \log S$ behaviour found for long strings rotating on $AdS_5\times S^5$ may be reproduced by membranes rotating on $AdS_4\times S^7$ and on a warped $AdS_5$ M-theory solution. We go on to obtain rotating membrane configurations with the same $E-K \sim \log K$ relation on $G_2$ holonomy backgrounds that are dual to ${\mathcal{N}}=1$ gauge theories in four dimensions. We study membrane configurations on $G_2$ holonomy backgrounds systematically, finding various other Energy-Charge relations. We end with some comments about strings rotating on warped backgrounds.Comment: 1+44 pages. Latex. No figures. Minor corrections to make all membrane configurations consistent. One configuration is now noncompac

Cosmic Strings in the Abelian Higgs Model with Conformal Coupling to Gravity

Cosmic string solutions of the abelian Higgs model with conformal coupling to gravity are shown to exist. The main characteristics of the solutions are presented and the differences with respect to the minimally coupled case are studied. An important difference is the absence of Bogomolnyi cosmic string solutions for conformal coupling. Several new features of the abelian Higgs cosmic strings of both types are discussed. The most interesting is perhaps a relation between the angular deficit and the central magnetic field which is bounded by a critical value.Comment: 22 pages, 10 figures; to appear in Phys. Rev.

Complete Classification of the String-like Solutions of the Gravitating Abelian Higgs Model

The static cylindrically symmetric solutions of the gravitating Abelian Higgs model form a two parameter family. In this paper we give a complete classification of the string-like solutions of this system. We show that the parameter plane is composed of two different regions with the following characteristics: One region contains the standard asymptotically conic cosmic string solutions together with a second kind of solutions with Melvin-like asymptotic behavior. The other region contains two types of solutions with bounded radial extension. The border between the two regions is the curve of maximal angular deficit of $2\pi$.Comment: 12 pages, 4 figure

Межэкспертная согласованность результатов МРТ диагностики патологии вращательной манжеты плечевого сустава

Background. The shoulder MRI is one of the main methods for the rotator cuff injuries diagnostics and determination of the further treatment tactics. The agreement in the MRI data interpretation among specialists regarding different types of shoulder ruptures is an integral part of diagnostic test validity evaluation. The purpose of this study was to assess the agreement in the MRI data interpretation in the patients with shoulder rotator cuff pathology among trauma surgeons, as well as between trauma surgeons and a radiologist. Materials and Methods. The study was a retrospective analysis of the MRI data and surgical reports regarding 57 patients with various shoulder pathologies undergone the shoulder MRI and arthroscopic shoulder revisions in the period from 2017 to 2019. There were 38 (67%) men and 19 (33%) women among the patients. The average age of the patients was 52.7±13.6 years. The sensitivity and specificity, as well as the shoulder MRI inter-rater reliability were assessed in the course of the study. Results. The rotator cuff pathology was revealed in 52 patients: supraspinatus tendon injury in 98% of cases, supraspinatus and infraspinatus tendon — in 26%, isolated subscapularis tendon injury — in 2%, supraspinatus and subscapularis tendon — in 39%. The maximal concordance in the MRI data interpretation was achieved in the patients with full-thickness supraspinatus tendon rupture, as well as with the supraspinatus tendon calcifications. However, significant disagreement was found between orthopedists with different work experience in determination of the presence and type of infraspinatus and subscapularis tendons pathology and supraspinatus tendon incomplete ruptures and tendinitis. Conclusion. The high agreement in the MRI data interpretation in determining the pathology of the shoulder rotator cuff among trauma surgeons, as well as between trauma surgeons and radiologists, was observed only regarding the supraspinatus tendon, calcifying tendonitis and full-thickness injury. The diagnosis of tendinitis and incomplete tendon rupture remains difficult. Their interpretation results vary greatly. It is also worth noting the heterogeneity of the results of diagnostics of the infraspinatus and subscapularis tendon pathology.Актуальность. МРТ плечевого сустава является одним из основных методов диагностики повреждений вращательной манжеты и определения дальнейшей тактики лечения. Согласованность результатов интерпретации МРТ между специалистами при различных вариантах разрывов плечевого сустава является неотъемлемой частью оценки эффективности диагностического теста. Цель — оценка согласованности интерпретации данных МРТ при патологии вращательной манжеты плечевого сустава между врачами-травматологами, а также между травматологами и рентгенологом. Материал и методы. Исследование представляет собой ретроспективный анализ результатов лучевых методов исследования и протоколов операций 57 пациентов с различными патологиями плечевого сустава, которым выполнялись МРТ плечевого сустава и артроскопическая ревизия плечевого сустава в период с 2017 по 2019 г. Среди обследованных было 38 (67%) мужчин и 19 (33%) женщин. Средний возраст пациентов составил 52,7±13,6 лет. В рамках работы была проведена оценка чувствительности и специфичности, а также межэкспертной надежности МРТ плечевого сустава. Результаты. У 52 пациентов была выявлена патология вращательной манжеты: в 98% случаев — повреждение сухожилия надостной мышцы, в 26% — сухожилия надостной и подостной мышц, в 2% — изолированное повреждение сухожилия подлопаточной мышцы и в 39% — повреждение сухожилий надостной и подлопаточной мышц. При анализе результатов максимальная согласованность интерпретации результатов МРТ была достигнута при определении полнослойного разрыва сухожилия надостной мышцы, а также кальцинатов сухожилия надостной мышцы. Однако были выявлены существенные разногласия между ортопедами с различным стажем работы в определении наличия и вида патологии сухожилий подостной и подлопаточной мышц, неполнослойных разрывов и тендиноза сухожилия надостной мышцы. Заключение. Высокая согласованность трактовки результатов МРТ в определении патологии вращательной манжеты плечевого сустава между травматологами, а также между травматологами и рентгенологами наблюдается только при оценке патологии сухожилия надостной мышцы, при кальцинирующем тендините и полнослойном повреждении. Диагностика тендинозов и неполнослойных разрывов остается затруднительной, и результаты интерпретации сильно разнятся. Стоит отметить также гетерогенность результатов диагностики патологии сухожилий подостной и подлопаточной мышц

Cosmological Non-Linearities as an Effective Fluid

The universe is smooth on large scales but very inhomogeneous on small scales. Why is the spacetime on large scales modeled to a good approximation by the Friedmann equations? Are we sure that small-scale non-linearities do not induce a large backreaction? Related to this, what is the effective theory that describes the universe on large scales? In this paper we make progress in addressing these questions. We show that the effective theory for the long-wavelength universe behaves as a viscous fluid coupled to gravity: integrating out short-wavelength perturbations renormalizes the homogeneous background and introduces dissipative dynamics into the evolution of long-wavelength perturbations. The effective fluid has small perturbations and is characterized by a few parameters like an equation of state, a sound speed and a viscosity parameter. These parameters can be matched to numerical simulations or fitted from observations. We find that the backreaction of small-scale non-linearities is very small, being suppressed by the large hierarchy between the scale of non-linearities and the horizon scale. The effective pressure of the fluid is always positive and much too small to significantly affect the background evolution. Moreover, we prove that virialized scales decouple completely from the large-scale dynamics, at all orders in the post-Newtonian expansion. We propose that our effective theory be used to formulate a well-defined and controlled alternative to conventional perturbation theory, and we discuss possible observational applications. Finally, our way of reformulating results in second-order perturbation theory in terms of a long-wavelength effective fluid provides the opportunity to understand non-linear effects in a simple and physically intuitive way.Comment: 84 pages, 3 figure

Higher dimensional dust collapse with a cosmological constant

The general solution of the Einstein equation for higher dimensional (HD) spherically symmetric collapse of inhomogeneous dust in presence of a cosmological term, i.e., exact interior solutions of the Einstein field equations is presented for the HD Tolman-Bondi metrics imbedded in a de Sitter background. The solution is then matched to exterior HD Scwarschild-de Sitter. A brief discussion on the causal structure singularities and horizons is provided. It turns out that the collapse proceed in the same way as in the Minkowski background, i.e., the strong curvature naked singularities form and that the higher dimensions seem to favor black holes rather than naked singularities.Comment: 7 Pages, no figure

Gravitational Coupling and Dynamical Reduction of The Cosmological Constant

We introduce a dynamical model to reduce a large cosmological constant to a sufficiently small value. The basic ingredient in this model is a distinction which has been made between the two unit systems used in cosmology and particle physics. We have used a conformal invariant gravitational model to define a particular conformal frame in terms of large scale properties of the universe. It is then argued that the contributions of mass scales in particle physics to the vacuum energy density should be considered in a different conformal frame. In this manner, a decaying mechanism is presented in which the conformal factor appears as a dynamical field and plays a key role to relax a large effective cosmological constant. Moreover, we argue that this model also provides a possible explanation for the coincidence problem.Comment: To appear in GR

Observation of a Narrow Resonance of Mass 2.46 GeV/c^2 Decaying to D_s^*+ pi^0 and Confirmation of the D_sJ^* (2317) State

Using 13.5 inverse fb of e+e- annihilation data collected with the CLEO II detector we have observed a narrow resonance in the Ds*+pi0 final state, with a mass near 2.46 GeV. The search for such a state was motivated by the recent discovery by the BaBar Collaboration of a narrow state at 2.32 GeV, the DsJ*(2317)+ that decays to Ds+pi0. Reconstructing the Ds+pi0 and Ds*+pi0 final states in CLEO data, we observe peaks in both of the corresponding reconstructed mass difference distributions, dM(Dspi0)=M(Dspi0)-M(Ds) and dM(Ds*pi0)=M(Ds*pi0)-M(Ds*), both of them at values near 350 MeV. We interpret these peaks as signatures of two distinct states, the DsJ*(2317)+ plus a new state, designated as the DsJ(2463)+. Because of the similar dM values, each of these states represents a source of background for the other if photons are lost, ignored or added. A quantitative accounting of these reflections confirms that both states exist. We have measured the mean mass differences = 350.0 +/- 1.2 [stat] +/- 1.0 [syst] MeV for the DsJ*(2317) state, and = 351.2 +/- 1.7 [stat] +/- 1.0 [syst] MeV for the new DsJ(2463)+ state. We have also searched, but find no evidence, for decays of the two states via the channels Ds*+gamma, Ds+gamma, and Ds+pi+pi-. The observations of the two states at 2.32 and 2.46 GeV, in the Ds+pi0 and Ds*+pi0 decay channels respectively, are consistent with their interpretations as (c anti-strange) mesons with orbital angular momentum L=1, and spin-parities of 0+ and 1+.Comment: 16 pages postscript, also available through http://w4.lns.cornell.edu/public/CLNS, version to be published in Physical Review D; minor modifications and fixes to typographical errors, plus an added section on production properties. The main results are unchanged; they supersede those reported in hep-ex/030501

Spin asymmetry A_1^d and the spin-dependent structure function g_1^d of the deuteron at low values of x and Q^2

We present a precise measurement of the deuteron longitudinal spin asymmetry A_1^d and of the deuteron spin-dependent structure function g_1^d at Q^2 < 1 GeV^2 and 4*10^-5 < x < 2.5*10^-2 based on the data collected by the COMPASS experiment at CERN during the years 2002 and 2003. The statistical precision is tenfold better than that of the previous measurement in this region. The measured A_1^d and g_1^d are found to be consistent with zero in the whole range of x.Comment: 17 pages, 10 figure