Measurement of migration of a humeral head resurfacing prosthesis using radiostereometry without implant marking: An experimental study

Today, the shoulder joint is the third most commonly replaced joint after the hip and knee joints and the incidence is increasing. In Sweden, 1863 primary Shoulder Arthroplasties and 195 revisions were performed in 2017. The most common diagnoses are Osteoarthritis and irreparable tears of the rotator cuff, with or without arthropathy, often referred to as cuff tear arthropathy. Different Shoulder Arthroplasty (SA) concepts include anatomical total shoulder arthroplasty (TSA), hemiarthroplasty (HSA) and reversed shoulder arthroplasty, but also humeral head resurfacing (HHR) and stemless arthroplasties. All concepts offer pain relief, improvement of function and in quality of life for the different diagnoses. Unfortunately, there are sometimes complications after SA. They involve periprosthetic joint infection, humeral and glenoid fractures, stress shielding, loosening of the glenoid and humeral component but also glenoid erosion and cuff rupture. Some of these complications are most common within 1 year after operation, some after several years, both may lead to a revision. This, together with the fact that new designs of implants and methods of fixation of SA continues to develop, stresses the importance of continuous monitoring of implant survival and follow-up. The overall aim of this thesis was to describe clinical examples of different methods to assess the outcome after Shoulder Arthroplasty. The most common methods are clinical examination, radiographic assessment, Patient Reported Outcome Measure (PROM), National Joint registries, where revisions are an important outcome, but also Clinical Trials. All of these methods are used in one or more of the 4 papers in this thesis and shows the complexity of the topic and the practical work. In paper I we used Radio Stereometric Analysis (RSA) in an experimental set-up and concluded that marker-free RSA can be used for a humeral head resurfacing arthroplasty. In paper II we used data from the Swedish Shoulder Arthroplasty Registry (SSAR) with PROM and revisions to conclude that age is the only factor that affects revision when comparing HSA and HHR. Paper III is a long-time follow-up of a Randomized controlled study where we used radiological assessment, PROM and revisions. The conclusion was that both TSA and HSA develop severe radiological changes 10 year after primary operation. Paper IV is a prospective RSA cohort study where we also evaluated PROM and revisions. The conclusion is that HHR seems to obtain a secure fixation in the humerus, after an initial migration. But also that the prostheses shows continuous glenoid wear. The main conclusion of this thesis is that patient’s operated with SA needs continuous monitoring and several methods may be used to evaluate the outcome

Avaliação da lordose lombar e sua relação com a dor lombopélvica em gestantes

O objetivo deste trabalho foi avaliar a magnitude da lordose lombar, sua influência na dor lombopélvica e a qualidade de vida em gestantes. Para tal, foi realizado um estudo com 20 mulheres não gestantes (C) e 13 gestantes ao longo dos trimestres gestacionais (G1, G2 e G3). Todas as mulheres foram submetidas à avaliação inicial para registro dos dados pessoais, hábitos de vida, antecedentes pessoais, uso de medicamentos, história ginecológica e obstétrica. Posteriormente, as voluntárias do grupo controle foram avaliadas uma vez e as gestantes foram avaliadas em três momentos distintos, no 10, 20 e 30 trimestres gestacionais. A avaliação do grau de lordose lombar foi realizada por meio de técnica fotogramétrica; a avaliação de locais de dor, o tipo de dor e sua intensidade foram feitas por meio do Questionário McGill de dor; e a avaliação da qualidade de vida foi feita pelo Questionário WHOQOL-bref. Neste trabalho, não foi possível observar padrão de alteração da curvatura lombar no decorrer da gestação. Também não foi observada relação entre a curvatura lombar e a dor lombopélvica relacionada à gestação.The purpose of this study was to evaluate the magnitude of lumbar lordosis, its influence on lumbopelvic pain and quality of life in pregnant women. To this end, a study was done with 20 non-pregnant women (C) and 13 pregnant women during the trimesters of pregnancy (G1, G2 and G3). All women underwent initial assessment for registration of personal data, lifestyle, personal history, medications, gynecological and obstetric history. Later, the volunteers in the control group were evaluated once and pregnant women were evaluated at three different times, the first, second and third trimesters of pregnancy. The evaluation of the degree of lumbar lordosis was performed by a photogrammetric technique. The assessment of points/places of pain, the kind of pain and its intensity were made by McGill Pain Questionnaire, and the quality of life assessment was made by WHOQOL-bref. In this study, it was not possible to observe a pattern of change in lumbar curvature during pregnancy. There was also no relationship between lumbar curvature and lumbopelvic pain related to pregnancy

Observations of Asymmetries in Ionospheric Return Flow During Different Levels of Geomagnetic Activity

It is known that the magnetic field of the Earth's closed magnetosphere can be highly displaced from the quiet‐day configuration when interacting with the interplanetary magnetic field (IMF), an asymmetry largely controlled by the dawn‐dusk component of the IMF. The corresponding ionospheric convection has revealed that footprints in one hemisphere tend to move faster to reduce the displacement, a process we refer to as the restoring of symmetry. Although the influence on the return flow convection from the process of restoring symmetry has been shown to be strongly controlled by the IMF, the influence from internal magnetospheric processes has been less investigated. We use 14 years of line‐of‐sight measurements of the ionospheric plasma convection from the Super Dual Auroral Radar Network to produce high‐latitude convection maps sorted by season, IMF, and geomagnetic activity. We find that the restoring symmetry flows dominate the average convection pattern in the nightside ionosphere during low levels of magnetotail activity. For increasing magnetotail activity, signatures of the restoring symmetry process become less and less pronounced in the global average convection maps. We suggest that tail reconnection acts to reduce the asymmetric state of the closed magnetosphere by removing the asymmetric pressure distribution in the tail set up by the IMF By interaction. During active periods the nightside magnetosphere will therefore reach a more symmetric configuration on a global scale. These results are relevant for better understanding the dynamics of flux tubes in the asymmetric geospace, which is the most common state of the system

Distinct responses of Gulf of Mexico phytoplankton communities to crude oil and the dispersant corexit® Ec9500A under different nutrient regimes

This study examines the potential effects of exposure to South Louisiana sweet crude oil (LSC), Corexit(A (R)) EC9500A, and dispersed oil on enclosed phytoplankton communities under different nutrient regimes. Three distinct microcosm experiments were conducted for 10 days to assess changes to the structure of natural communities from the Gulf of Mexico as quantified by temporal changes in the biomasses of different phytoplankton groups. Concentration of NO3, Si and PO4 were 0.83, 0.99 and 0.09 mu M for the unenriched treatments and 14.07, 13.01 and 0.94 mu M for the enriched treatments, respectively. Overall, the contaminants LSC and Corexit(A (R)) EC9500A led to a decrease in the number of sensitive species and an increase in more resistant species. Phytoplankton communities showed more sensitivity to LSC under nutrient-limited conditions. The addition of nutrients to initially nutrient-limited treatments lessened the inhibitory effect of LSC in the short term. Centric diatoms benefited most from this enrichment, but pennate diatoms demonstrated considerably greater tolerance to crude oil at low crude oil concentrations in nutrient-enriched treatments. Dinoflagellates showed relatively higher tolerance in nutrient-limited treatments and high crude oil concentrations. Corexit(A (R)) EC9500A inputs significantly increased the toxicity of crude oil. Corexit(A (R)) EC9500A alone had a highly inhibitory effect at 63 ppm on phytoplankton communities. This study highlights the fact that different nutrient regimes play a major role in determining the shifts of the phytoplankton community in response to exposure to different concentrations of crude oil and dispersant. Determination of the functional equivalence of shifted phytoplankton groups could complement our research and allow for more pertinent extrapolation to real world conditions