The controversy of patellar resurfacing in total knee arthroplasty: Ibisne in medio tutissimus?

Early arthroplasty designs were associated with a high level of anterior knee pain as they failed to cater for the patello-femoral joint. Patellar resurfacing was heralded as the saviour safeguarding patient satisfaction and success but opinion on its necessity has since deeply divided the scientific community and has become synonymous to topics of religion or politics. Opponents of resurfacing contend that the native patella provides better patellar tracking, improved clinical function, and avoids implant-related complications, whilst proponents argue that patients have less pain, are overall more satisfied, and avert the need for secondary resurfacing. The question remains whether complications associated with patellar resurfacing including those arising from future component revision outweigh the somewhat increased incidence of anterior knee pain recorded in unresurfaced patients. The current scientific literature, which is often affected by methodological limitations and observer bias, remains confusing as it provides evidence in support of both sides of the argument, whilst blinded satisfaction studies comparing resurfaced and non-resurfaced knees generally reveal equivalent results. Even national arthroplasty register data show wide variations in the proportion of patellar resurfacing between countries that cannot be explained by cultural differences alone. Advocates who always resurface or never resurface indiscriminately expose the patella to a random choice. Selective resurfacing offers a compromise by providing a decision algorithm based on a propensity for improved clinical success, whilst avoiding potential complications associated with unnecessary resurfacing. Evidence regarding the validity of selection criteria, however, is missing, and the decision when to resurface is often based on intuitive reasoning. Our lack of understanding why, irrespective of pre-operative symptoms and patellar resurfacing, some patients may suffer pain following TKA and others may not have so far stifled our efforts to make the strategy of selective resurfacing succeed. We should hence devote our efforts in defining predictive criteria and indicators that will enable us to reliably identify those individuals who might benefit from a resurfacing procedure. Level of evidence V

Addressing vulnerability, building resilience:community-based adaptation to vector-borne diseases in the context of global change

Abstract Background The threat of a rapidly changing planet – of coupled social, environmental and climatic change – pose new conceptual and practical challenges in responding to vector-borne diseases. These include non-linear and uncertain spatial-temporal change dynamics associated with climate, animals, land, water, food, settlement, conflict, ecology and human socio-cultural, economic and political-institutional systems. To date, research efforts have been dominated by disease modeling, which has provided limited practical advice to policymakers and practitioners in developing policies and programmes on the ground. Main body In this paper, we provide an alternative biosocial perspective grounded in social science insights, drawing upon concepts of vulnerability, resilience, participation and community-based adaptation. Our analysis was informed by a realist review (provided in the Additional file 2) focused on seven major climate-sensitive vector-borne diseases: malaria, schistosomiasis, dengue, leishmaniasis, sleeping sickness, chagas disease, and rift valley fever. Here, we situate our analysis of existing community-based interventions within the context of global change processes and the wider social science literature. We identify and discuss best practices and conceptual principles that should guide future community-based efforts to mitigate human vulnerability to vector-borne diseases. We argue that more focused attention and investments are needed in meaningful public participation, appropriate technologies, the strengthening of health systems, sustainable development, wider institutional changes and attention to the social determinants of health, including the drivers of co-infection. Conclusion In order to respond effectively to uncertain future scenarios for vector-borne disease in a changing world, more attention needs to be given to building resilient and equitable systems in the present

Estudo comparativo dos meios de contraste baritado e iodado-iônico e não-iônico no trato respiratório de ratos Comparative study of barium and iodine agents - ionic and nonionic on the respiratory tract of the rats

OBJETIVO: Durante estudos radiológicos pode ocorrer a passagem do meio de contraste para a árvore traqueo-brônquica, determinando reações adversas e até fatais. O objetivo deste estudo é conhecer as alterações desencadeadas no trato respiratório pela presença do meio de contraste. MÉTODOS: Utilizaram-se 91 ratos divididos, aleatoriamente, em 4 grupos. Um grupo de controle não manipulado com 7 animais e os demais grupos com 21 ratos. O grupo controle manipulado recebeu solução fisiológica e os grupos de experimento: bário, iodo ônico e iodo não iônico conforme o grupo a que pertenciam. Sob anestesia e visibilização direta da traquéia, injetou-se 0,75 ml/kg (0,25 ml) do meio de contraste de acordo com o grupo ao qual pertencesse o animal. Realizaram-se as aferições com 1 hora, 1 dia e 1 semana. Os ratos foram sorteados para a autanásia nos três tempos estudados. Fez-se documentação radiográfica seguida da ressecção dos pulmões e exame histo-patológico. RESULTADOS: Na primeira hora, no grupo que recebeu bário, os campos médios e o superior direito ficaram acometidos. Nos grupos que receberam iodo iônico e iodo não iônico, todo o pulmão direito mostrava-se opacificado. Nas avaliações de uma dia e 1 semana os grupos que receberam iodo estavam normais enquanto que o grupo que recebeu bário mostrava comprometimento dos campos médios. No estudo histo-patológico observou-se, no grupo que recebeu bário, na avaliação de uma semana, grande quantidade de macrófagos intra-alveolares, perivasculares e peribrônquicos. CONCLUSÃO: Os contrastes iodados iônico e não iônico levam a alterações passageiras enquanto que o bário promove reação inflamatória crônica com manutenção da tradução radiográfica, no rato.<br>PURPOSE: During roadiologic studies, passage of the contrast medium to the tracheobronchial tree may occur, causibng adverse or even fatal reactions. The objective of the present study was to determine the changes in the respiratory tract triggered by the presence of contrast medium. METHODS: Ninety-one rats were divided at random into 5 groups, i.e., an intact control group of 7 animals and 4 groups of 21 rats each. The manipulated control group received physiological saline and the experimental groups respectively received barium, ionic iodine and non-ionic iodine. Under anesthesia and direct visualization of the trachea, 0.75 ml/kg (0.25 ml) of the contrast medium was injected into the animals of each group. The effects of the procedure were determined after 1 hour, 1 day and 1 week, with the animals being sacrificed at each time point by drawing lots. Radiographic documentation was obtained, followed by resection and histopathologic examination of the lungs. RESULTS: After 1 hour, the middle fields and the right upper field were involved in the group injected with barium. In the groups injected with ionic iodine and non-ionic iodine, the entire right lung was found to be opacified. After 1 day and 1 week, the groups injected with iodine were normal, whereas the group injected with barium showed involvement of the middle fields. After 1 week, histopathologic examination revealed that the group injected with barium exhibited large amounts of intra-alveolar, perivascular and peribronchial macrophages CONCLUSION: The ionic and non-ionic iodine contrast media led to temporary changes, whereas barium promoted a chronic inflammatory reaction with maintenance of radiographic translation