Imaging of knee injuries with special focus on tibial plateau fractures

Acute knee injury is a common event throughout life, and it is usually the result of a traffic accident, simple fall, or twisting injury. Over 90% of patients with acute knee injury undergo radiography. An overlooked fracture or delayed diagnosis can lead to poor patient outcome. The major aim of this thesis was retrospectively to study imaging of knee injury with a special focus on tibial plateau fractures in patients referred to a level-one trauma center. Multi-detector computed tomography (MDCT) findings of acute knee trauma were studied and compared to radiography, as well as whether non-contrast MDCT can detect cruciate ligaments with reasonable accuracy. The prevalence, type, and location of meniscal injuries in magnetic resonance imaging (MRI) were evaluated, particularly in order to assess the prevalence of unstable meniscal tears in acute knee trauma with tibial plateau fractures. The possibility to analyze with conventional MRI the signal appearance of menisci repaired with bioabsorbable arrows was also studied. The postoperative use of MDCT was studied in surgically treated tibial plateau fractures: to establish the frequency and indications of MDCT and to assess the common findings and their clinical impact in a level-one trauma hospital. This thesis focused on MDCT and MRI of knee injuries, and radiographs were analyzed when applica-ble. Radiography constitutes the basis for imaging acute knee injury, but MDCT can yield information beyond the capabilities of radiography. Especially in severely injured patients , sufficient radiographs are often difficult to obtain, and in those patients, radiography is unreliable to rule out fractures. MDCT detected intact cruciate ligaments with good specificity, accuracy, and negative predictive value, but the assessment of torn ligaments was unreliable. A total of 36% (14/39) patients with tibial plateau fracture had an unstable meniscal tear in MRI. When a meniscal tear is properly detected preoperatively, treatment can be combined with primary fracture fixation, thus avoiding another operation. The number of meniscal contusions was high. Awareness of the imaging features of this meniscal abnormality can help radiologists increase specificity by avoiding false-positive findings in meniscal tears. Postoperative menisci treated with bioabsorbable arrows showed no difference, among different signal intensities in MRI, among menisci between patients with operated or intact ACL. The highest incidence of menisci with an increased signal intensity extending to the meniscal surface was in patients whose surgery was within the previous 18 months. The results may indicate that a rather long time is necessary for menisci to heal completely after arrow repair. Whether the menisci with an increased signal intensity extending to the meniscal surface represent improper healing or re-tear, or whether this is just the earlier healing feature in the natural process remains unclear, and further prospective studies are needed to clarify this. Postoperative use of MDCT in tibial plateau fractures was rather infrequent even in this large trauma center, but when performed, it revealed clinically significant information, thus benefitting patients in regard to treatment.Akuutti polvivamma on yleinen tapaturma aikuisväestössä. Se on useimmiten seurausta liikenneonnettomuudesta, kaatumisesta tai vääntövammasta. Polven röntgenkuvaus onkin yleisin radiologinen kuvaus tapaturma-asemilla ja yli 90% tapaturma-asemille hakeutuvista polvivammapotilaista otetaan polven röntgenkuvat. Näistä potilaista 6-12% on todella polvimurtuma. Polvimurtuman viivästynyt diagnoosi voi johtaa huonoon hoitotulokseen. Väitöskirjassa tutkittiin polvivammoja; erityisesti sääriluun nivelpinnan käsittävien murtumien löydöksiä. Tutkimusaineisto koostui suuren traumasairaalan potilaista. Tutkimuksen pääpaino oli monileiketietokonetomografia- ja magneettitutkimuksissa ja perinteisten röntgenkuvien löydöksiä ei analysoitu kaikissa osatöissä. Akuutin polvivamman löydöksiä tutkittiin monileiketietokonetomografian avulla ja verrattiin perinteiseen röntgenkuvaukseen, lisäksi selvitettiin monileiketietokonetomografian mahdollisuuksia pehmytkudosten vammojen diagnostiikassa. Polven nivelpinnan murtumiin liittyvien polven nivelkierukoiden vammojen yleisyyttä, erilaisia vammatyyppejä ja erityisesti hoidettavien vammojen esiintyvyyttä selvitettiin. Väitöskirjassa selvitettiin biohajoavilla nuolilla kirurgisesti hoidettujen nivelkierukoiden magneettikuvauslöydöksiä, sekä tutkittiin monileiketietokonetomografian käyttöä kirurgisesti hoidettujen polvien nivelpinnan murtumien seurannassa. Röntgenkuvat olivat riittävät ensisijaisena tutkimuksena akuutin polvivamman kuvantamisessa suurimmalle osalle potilaista, mutta vakavasti loukkaantuneilla potilailla röntgenkuvaus ei välttämättä riittänyt poissulkemaan murtumaa ja heille suositellaan jatkotutkimuksena monileiketietokonetomografian käyttöä. Polven ristisiteiden kuvantamisessa monileiketietokonetomografian avulla ehjät ristisiteet erottuivat luotettavasti, mutta revenneiden ristisiteiden osalta kuvantaminen oli epäluotettavaa. Sääriluun nivelpinnan käsittävien murtumien yhteydessä löytyi paljon polven nivelkierukoiden epästabiileja re-peämiä, jotka yleensä vaativat kirurgista hoitoa. Näiden murtumien yhteydessä magneettikuvaus onkin suositeltavaa. Biohajoavin nuolin korjattujen polven nivelkierukoiden kuvantaminen perinteisellä magneettikuvauksella osoittautui epävarmaksi potilaiden seurannassa ja erityistä nivelensisäistä kontras-tiainetta suositellaan käytettäväksi ainakin niille potilaille, joilla toimenpiteestä on kulunut alle 18kk. Kirurgisesti hoidettujen sääriluun nivelpinnan käsittävien murtumien jatkoseuranta toteutetaan nykyisin pääosin perinteisellä röntgenkuvauksella ja jopa tässä suuressa traumasairaalassa vain 9% hoidetuista potilaista tehtiin jatkotutkimuksena monileiketietokonetomografia tutkimus. Näissä tapauksissa monileiketietokonetomografian avulla saatiin kuitenkin potilaiden hoitoa hyödyttävää lisätietoa

Hantavirus Research in Finland: Highlights and Perspectives

Finland has the highest incidence of hantavirus infections globally, with a significant impact on public health. The large coverage of boreal forests and the cyclic dynamics of the dominant forest rodent species, the bank vole Myodes glareolus, explain most of this. We review the relationships between Puumala hantavirus (PUUV), its host rodent, and the hantavirus disease, nephropathia epidemica (NE), in Finland. We describe the history of NE and its diagnostic research in Finland, the seasonal and multiannual cyclic dynamics of PUUV in bank voles impacting human epidemiology, and we compare our northern epidemiological patterns with those in temperate Europe. The long survival of PUUV outside the host and the life-long shedding of PUUV by the bank voles are highlighted. In humans, the infection has unique features in pathobiology but rarely long-term consequences. NE is affected by specific host genetics and risk behavior (smoking), and certain biomarkers can predict the outcome. Unlike many other hantaviruses, PUUV causes a relatively mild disease and is rarely fatal. Reinfections do not exist. Antiviral therapy is complicated by the fact that when symptoms appear, the patient already has a generalized infection. Blocking vascular leakage measures counteracting pathobiology, offer a real therapeutic approach

Long-Term Consequences of Puumala Hantavirus Infection

Several viral infections are associated with acute and long-term complications. During the past two years, there have been many reports on post-infectious symptoms of the patients suffering from COVID-19 disease. Serious complications occasionally occur during the acute phase of Puumala orthohantavirus caused nephropathia epidemica. Severe long-term consequences are rare. Fatigue for several weeks is quite common. Hormonal insufficiencies should be excluded if the patient does not recover normally.Peer reviewe

Trophic overlap between expanding and contracting fish predators in a range margin undergoing change

Climate change is predicted to cause a freshening of the Baltic Sea, facilitating range expansions of freshwater species and contractions of marine. Resident marine flounders (Platichthys flesus) and expansive freshwater roach (Rutilus rutilus) are dominant consumers in the Baltic Sea sublittoral where they occur in partial sympatry. By comparing patterns of resource use by flounders and roach along a declining resource gradient of blue mussels (Mytilus trossulus) our aim was to explore predator functional responses and the degree of trophic overlap. Understanding the nature of density-dependent prey acquisition has important implications for predicting population dynamics of both predators and their shared prey. Results showed a highly specialized diet for both species, high reliance on blue mussels throughout the range, similar prey size preference and high trophic overlap. Highest overlap occurred where blue mussels were abundant but overlap was also high where they were scarce. Our results highlight the importance of a single food item - the blue mussel - for both species, likely promoting high population size and range expansion of roach. Findings also suggest that range expansion of roach may have a top-down structuring force on mussels that differ in severity and location from that originating from resident flounders.Peer reviewe

Long-Term Consequences of Puumala Hantavirus Infection

Several viral infections are associated with acute and long-term complications. During the past two years, there have been many reports on post-infectious symptoms of the patients suffering from COVID-19 disease. Serious complications occasionally occur during the acute phase of Puumala orthohantavirus caused nephropathia epidemica. Severe long-term consequences are rare. Fatigue for several weeks is quite common. Hormonal insufficiencies should be excluded if the patient does not recover normally

Neutrophil Activation in Acute Hemorrhagic Fever With Renal Syndrome Is Mediated by Hantavirus-Infected Microvascular Endothelial Cells

Hantaviruses cause hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS) in humans. Both diseases are considered to be immunologically mediated but the exact pathological mechanisms are still poorly understood. Neutrophils are considered the first line of defense against invading microbes but little is still known of their role in virus infections. We wanted to study the role of neutrophils in HFRS using blood and tissue samples obtained from Puumala hantavirus (PUUV)-infected patients. We found that neutrophil activation products myeloperoxidase and neutrophil elastase, together with interleukin-8 (the major neutrophil chemotactic factor in humans), are strongly elevated in blood of acute PUUV-HFRS and positively correlate with kidney dysfunction, the hallmark clinical finding of HFRS. These markers localized mainly in the tubulointerstitial space in the kidneys of PUUV-HFRS patients suggesting neutrophil activation to be a likely component of the general immune response toward hantaviruses. We also observed increased levels of circulating extracellular histones at the acute stage of the disease supporting previous findings of neutrophil extracellular trap formation in PUUV-HFRS. Mechanistically, we did not find evidence for direct PUUV-mediated activation of neutrophils but instead primary blood microvascular endothelial cells acquired a pro-inflammatory phenotype and promoted neutrophil degranulation in response to PUUV infection in vitro. These results suggest that neutrophils are activated by hantavirus-infected endothelial cells and may contribute to the kidney pathology which determines the severity of HFRS.Peer reviewe

Sosiodemografiset tekijät ja elämäntapa matkailukulutusta selittävinä tekijöinä: kausaalinen analyysi

Sociodemographic variables and lifestyles as explanatory factors for tourism consumption: Causal analysis Postmodern theories state that instead of demographics, social divisions are based on identity and lifestyle. In this article, the effects of these both were examined. Tourism consumption was divided into two dimensions, “actual tourism” and “desire to travel more”. Analysis was based on survey “Finland 2004”. Sociodemographic factors were assumed to influence more on actual tourism than on desire to travel more. However, sociodemographic variables might influence on travelling habits also inderectly through life-styles. The results strengthened the hypothesis. The effect of lifestyles was quite strong but sociodemographic factors had still direct but also indirect effect via lifestyles.Postmodern theories state that instead of demographics, social divisions are based on identity and lifestyle. In this article, the effects of these both were examined. Tourism consumption was divided into two dimensions, “actual tourism” and “desire to travel more”. Analysis was based on survey “Finland 2004”. Sociodemographic factors were assumed to influence more on actual tourism than on desire to travel more. However, sociodemographic variables might influence on travelling habits also inderectly through life-styles. The results strengthened the hypothesis. The effect of lifestyles was quite strong but sociodemographic factors had still direct but also indirect effect via lifestyles

Vain Puumala-virus aiheuttaa myyräkuumetta

KommenttiHantavirusten aiheuttamat ¬infektiot eroavat toisistaan taudinkuvaltaan ja vaikeudeltaan