Second-generation uncemented stems: excellent 5-13-year results

Introduction: The purpose of this study was to prospectively evaluate the 5-13-year results of a cementless total hip arthroplasty with a special focus on the survivorship, occurrence of osteolysis, incidence of intraoperative femoral fractures, thigh pain, and cortical hypertrophy of the femoral stem. The femoral component used in this study was titanium fluted, slotted, symmetrical component that was prepared with intraoperative machining. The proximal third of the stem had hydroxyl-apatite coating and horizontal steps. Methods: The clinical and radiographical results of a consecutive series of 157 total hip arthroplasties (124 patients) with this stem were investigated. Minimum follow-up was 5years. The average age of the patients at the time of surgery was 47years. Three patients died and ten patients were lost to follow-up, leaving 142 hips for evaluation. The clinical result was evaluated on the basis of the Merle d'Aubigné score, complications and thigh pain. A detailed radiographic analysis was performed at each follow-up visit. Kaplan-Meier survivorship analysis was performed to evaluate stem, cup, and bearing survivorship. Results: The mean follow-up was 8.5years (range 5-13years). The average Merle d'Aubigné score improved from 10.5 points preoperatively to 17.4 points postoperatively. The cumulative 10-year survival rate was 99% for the femoral component, 99% for the acetabular component, and 69% for the bearing. Thigh pain was identified in three patients (2%). There was no distal femoral osteolysis. Seventy-nine percent of all the hips had endosteal spot welds around the coated, proximal one-third of the prosthesis. 51% had radiodense lines around the distal tip of the prosthesis, and 3% had cortical hypertrophy. One undersized stem and one cup were revised for aseptic loosening, and 25 bearings were exchanged. Conclusions: Uncemented, machined, fluted titanium canal-filling femoral components achieve reliable fixation in this young patient population. They have a decreased incidence of activity-related thigh pain, lower rate of intraoperative femur fractures and cortical hypertrophy with comparable bone-ingrowth in comparison to other second-generation uncemented femoral components described in literature. Bearing wear and the need for bearing exchange was the only limitation of these construct

LCPD: Reduced Range of Motion Resulting From Extra- and Intraarticular Impingement

Background: Legg-Calvé-Perthes disease (LCPD) often results in a deformity that can be considered as a complex form of femoroacetabular impingement (FAI). Improved preoperative characterization of the FAI problem based on a noninvasive three-dimensional computer analysis may help to plan the appropriate operative treatment. Questions/purposes: We asked whether the location of impingement zones, the presence of additional extraarticular impingement, and the resulting ROM differ between hips with LCPD and normal hips or hips with FAI. Methods: We used a CT-based virtual dynamic motion analysis based on a motion algorithm to simulate the individual motion for 13 hips with LCPD, 22 hips with FAI, and 27 normal hips. We then determined the motion and impingement pattern of each hip for the anterior (flexion, adduction, internal rotation) and the posterior impingement tests (extension, adduction, external rotation). Results: The location of impingement zones in hips with LCPD differed compared with the FAI/normal groups. Intra- and extraarticular impingement was more frequent in LCPD (79% and 86%, respectively) compared with normal (15%, 15%) and FAI hips (36%, 14%). Hips with LCPD had decreased amplitude for all hip motions (flexion, extension, abduction, adduction, internal and external rotation) compared with FAI or normal. Conclusions: Hips with LCPD show a decreased ROM as a result of a higher prevalence of intra- and extraarticular FAI. Noninvasive assessment of impingement characteristics in hips with LCPD may be helpful in the future for establishment of a surgical pla

Clinical presentation of a traumatic cervical spine disc rupture in alpine sports: a case report

Isolated non-skeletal injuries of the cervical spine are rare and frequently missed. Different evaluation algorithms for C-spine injuries, such as the Canadian C-spine Rule have been proposed, however with strong emphasis on excluding osseous lesions. Discoligamentary injuries may be masked by unique clinical situations presenting to the emergency physician. We report on the case of a 28-year-old patient being admitted to our emergency department after a snowboarding accident, with an assumed hyperflexion injury of the cervical spine. During the initial clinical encounter the only clinical finding the patient demonstrated, was a burning sensation in the palms bilaterally. No neck pain could be elicited and the patient was not intoxicated and did not have distracting injuries. Since the patient described a fall prevention attempt with both arms, a peripheral nerve contusion was considered as a differential diagnosis. However, a high level of suspicion and the use of sophisticated imaging (MRI and CT) of the cervical spine, ultimately led to the diagnosis of a traumatic disc rupture at the C5/6 level. The patient was subsequently treated with a ventral microdiscectomy with cage interposition and ventral plate stabilization at the C5/C6 level and could be discharged home with clearly improving symptoms and without further complications

Epidemiologic analysis of 8000 acute vertebral fractures: evolution of treatment and complications at 10-year follow-up.

STUDY DESIGN This is a retrospective cohort study. OBJECTIVES This study aims to determine the proportional incidence, clinical characteristics, treatment patterns with complications and changes in treatment of vertebral fractures over 10 years at a Swiss university hospital. METHODS A retrospective cohort study was performed. All patients with an acute vertebral fracture were included in this study. The extracted anonymized data from the medical records were manually assessed. Demographic data, exact location, etiology, type of treatment and complications related to the treatment were obtained. RESULTS Of 330,225 treated patients, 4772 presented with at least one vertebral fracture. In total 8307 vertebral fractures were identified, leading to a proportional incidence of 25 vertebral fractures in 1000 patients. Fractures were equally distributed between genders. Male patients were significantly younger and more likely to sustain a traumatic fracture, while female patients more commonly presented with osteoporotic fractures. The thoracolumbar junction (Th11-L2) was the most frequent fracture site in all etiologies. More than two-thirds of vertebral fractures were treated surgically (68.6%). Out of 4622 performed surgeries, we found 290 complications (6.3%). The odds for surgical treatment in osteoporotic fractures were two times higher before 2010 compared to 2010 and after (odds ratio: 2.1, 95% CI 1.5-2.9, p < 0.001). CONCLUSION Twenty-five out of 1000 patients presented with a vertebral fracture. More than 4000 patients with over 8307 vertebral body fractures were treated in 10 years. Over two-thirds of all fractures were treated surgically with 6.3% complications. There was a substantial decrease in surgeries for osteoporotic fractures after 2009

Nachwuchsförderung

Nachwuchswissenschaftler und Nachwuchswissenschaftlerinnen befinden sich in einer vielschichtigen Situation: Sie sind in Lehre und Forschung eingebunden, Mitarbeiter/in am Lehrstuhl oder in einem Projekt und stehen in einem ständigen Betreuungs- und Begutachtungsprozess. Der Wunsch zu promovieren ist schnell gefasst. Schnell jedoch holt einen der Alltag ein und man erkennt, Promovieren hat auch ganz viel mit Organisation, Administration und Durchhalten zu tun. Die Förderung des wissenschaftlichen Nachwuchses ist eine grundlegende Aufgabe der Universität. Sie wird auch Ernst genommen. Davon zeugen z. B. Mentoring-Programme, Promotionskollegs und Doktorandentrainings. Was vielerorts jedoch noch fehlt, sind geeignete Maßnahmen der Personalentwicklung, um eine Karriere außerhalb der Hochschule zu ermöglichen. Einige dieser Themen werden in dem vorliegenden Heft ausführlicher behandelt. Den Anfang macht Jutta Wergen. In ihrem Aufsatz „Will ich oder will ich nicht – und wenn ja, wie? Promovieren!!!“ zeigt sie Wege durch das Labyrinth. Sie beschreibt die verschiedenen Phasen einer Promotion und weist auf die Formalitäten hin. Sie zeigt, wie sich die Zeit des Promovierens finanzieren lässt. Und sie spricht auch das sehr wichtige Thema der Betreuung an. Detaillierter auf diese Beziehung geht Sigrid Metz-Göckel in ihrem Beitrag „Die Freuden und Risiken der Betreuung von Doktorarbeiten oder: Promotionen zahlen sich aus“ ein. Unabhängig davon, ob das Promovieren in einem strukturierten Prozess oder einem traditionellen Betreuungsverhältnis abläuft, auf ihrem Weg zu einer eigenständigen wissenschaftlichen Persönlichkeit können Promovierende ihren Betreuer/inne/n fachlich überlegen und die Betreuer/innen zu deren Begleiter/inne/n werden – was von Metz-Göckel als große Bereicherung ihrer eigenen wissenschaftlichen Tätigkeit erlebt wird. Dass Promovieren mehr ist als das reine Schreiben der Dissertation, betont auch Ulrike Senger in ihrem Beitrag „Kompetenzentwicklung Promovierender – Impulse für universitäres Forschen, Führen und Lehren Lernen“. Die Autorin richtet ihren nüchternen und empathischen Blick auf die Person, die promoviert und auf das, was sie während dieser Zeit lernt. Promovierende schaffen nicht nur Kultur, sie können auch zu „‘Change Agents‘“ im persönlichen, organisatorischen und universitären Bereich werden. Andrea Kottmann und Brigitte Ecker widmen sich in ihrem Beitrag „Die Zukunft der Finanzierung der Doktorandenausbildung“ der Art der Finanzierung der Promotionsphase, die wesentlich dazu beiträgt, in welchem Ausmaß eine qualitativ hochwertige Ausbildung angeboten und durchgeführt werden kann. An ausgewählten Beispielen diskutieren sie zwei Finanzierungsmodelle und weisen auf die unmittelbaren Auswirkungen auf die Profilbildung der Universitäten und die Finanzierung der Promovierenden hin. Der Empfehlung des Wissenschaftsrats und der Forderung der Universitäten an die Hochschuldidaktik als eine serviceorientierte Einrichtung ohne eigene wissenschaftliche Ausrichtung steht der Anspruch der in der Hochschuldidaktik tätigen Wissenschaftler/innen gegenüber. Wie es ist, in einem Fach zu promovieren, das sich aus Bezugswissenschaften zusammensetzt, und wo die Promovierenden Austausch und Vernetzung finden, thematisiert Timo van Treeck in seinem Aufsatz „Raue See und neblige Horizonte: Die Promotion in der Hochschuldidaktik“. Vom „akademischen Prekariat“ ist seit einiger Zeit schlagwortmäßig zu lesen. In „Absicherung gibt es überhaupt keine, man kann nur hoffen…“ widmet sich Lisa Sigl diesem Thema und fragt: Wie erleben junge Forscher/innen den Widerspruch, dass ihre Forschung, deren Verlauf und Ergebnis prinzipiell nicht planbar sind, mit der notwendigen Planung ihrer Erwerbsbiografie und Karriere koordiniert werden muss? Sie greift damit in die Debatte um „‘Governance‘“ und „‘Self-Governance‘“ von Forschungskulturen ein und macht deutlich, welchen Einfluss die Rahmenbedingungen sowohl auf die Art und Weise der Produktion von Wissen haben als auch darauf, welches Wissen überhaupt produziert wird. „Wer geht wohin?“ fragen Ramona Schürmann und Thorben Sembritzki und referieren Ergebnisse der WiNbus-Studie zu Laufbahnintentionen junger Nachwuchswissenschaftler/innen. Bis zu 80 % der promovierten Nachwuchswissenschaftler/innen verlassen die Universität. Schürmann und Sembritzki interessieren sich für deren zukünftige Beschäftigungsbereiche und für die Faktoren, die ein Gehen oder Bleiben beeinflussen. „Auf dem Weg zur Professur – Bessere Chancen durch Berufsberatung?“ von Oliver Kayser ermuntert zukünftige Bewerber/innen in zupackender Hands-on-Mentalität sich aktiv den Anforderungen in einem Berufungsverfahren zu stellen. Er beschreibt die einzelnen Stationen ausführlich und eindrücklich und fordert dazu auf, sich selbst und die eigene Situation richtig einschätzen zu lernen, u. U. mit Hilfe externer Profis

LCPD: reduced range of motion resulting from extra- and intraarticular impingement

Legg-Calvé-Perthes disease (LCPD) often results in a deformity that can be considered as a complex form of femoroacetabular impingement (FAI). Improved preoperative characterization of the FAI problem based on a noninvasive three-dimensional computer analysis may help to plan the appropriate operative treatment

Automated HW/SW co-design for edge AI : State, challenges and steps ahead

Gigantic rates of data production in the era of Big Data, Internet of Thing (IoT), and Smart Cyber Physical Systems (CPS) pose incessantly escalating demands for massive data processing, storage, and transmission while continuously interacting with the physical world using edge sensors and actuators. For IoT systems, there is now a strong trend to move the intelligence from the cloud to the edge or the extreme edge (known as TinyML). Yet, this shift to edge AI systems requires to design powerful machine learning systems under very strict resource constraints. This poses a difficult design task that needs to take the complete system stack from machine learning algorithm, to model optimization and compression, to software implementation, to hardware platform and ML accelerator design into account. This paper discusses the open research challenges to achieve such a holistic Design Space Exploration for a HW/SW Co-design for Edge AI Systems and discusses the current state with three currently developed flows: one design flow for systems with tightly-coupled accelerator architectures based on RISC-V, one approach using loosely-coupled, application-specific accelerators as well as one framework that integrates software and hardware optimization techniques to built efficient Deep Neural Network (DNN) systems.publishedVersionPeer reviewe

GrassPlot - a database of multi-scale plant diversity in Palaearctic grasslands

GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board

The Crowdsourced Replication Initiative: Investigating Immigration and Social Policy Preferences. Executive Report.

In an era of mass migration, social scientists, populist parties and social movements raise concerns over the future of immigration-destination societies. What impacts does this have on policy and social solidarity? Comparative cross-national research, relying mostly on secondary data, has findings in different directions. There is a threat of selective model reporting and lack of replicability. The heterogeneity of countries obscures attempts to clearly define data-generating models. P-hacking and HARKing lurk among standard research practices in this area.This project employs crowdsourcing to address these issues. It draws on replication, deliberation, meta-analysis and harnessing the power of many minds at once. The Crowdsourced Replication Initiative carries two main goals, (a) to better investigate the linkage between immigration and social policy preferences across countries, and (b) to develop crowdsourcing as a social science method. The Executive Report provides short reviews of the area of social policy preferences and immigration, and the methods and impetus behind crowdsourcing plus a description of the entire project. Three main areas of findings will appear in three papers, that are registered as PAPs or in process