Calcaneal ultrasound as a screening test for osteoporosis

Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/OpenIntroduction: Dual energy X-ray absorptiometry (DEXA) has been the cornerstone in the diagnosis of osteoporosis. Quantitative ultrasound (QUS) of calcaneus is easy to perform and cheaper than DEXA but prior studies have shown a limited correlation and agreement between the two tests. The purpose of this study was to assess calcaneal ultrasound as a screening test for osteoporosis. Material and methods: Two-hundred-ninety-seven 70-years-old Icelandic women underwent a DEXA measurement of lumbar spine, left hip and whole body as well as QUS of left calcaneus. We assessed the correlation and agreement between the two tests and searched for the optimal cut-off point in QUS for the diagnosis of osteoporosis from sensitivity and specificity calculations and ROC curves. We also examined correlation between DEXA or QUS and anthropometric or biochemical measurements of bone markers. Finally, we compared the women who had sustained a fracture to those who had not with regard to DEXA and QUS. Results: The correlation between DEXA at different sites and QUS ranged form 0.40 to 0.57 (Spearman's correlation coefficient) with the best correlation for left hip DEXA. The best sensitivity/specificity relationship of QUS in diagnosis of osteoporosis (WHO criteria) at the hip, was found for QUS T-score of -2.5; sensitivity 91.7%, specificity 49.0%, positive predictive value 25.8% and negative predictive value of 96.8%. Kappa-statistic showed a marginal agreement between the two tests (k=0.25, p<0.01). The correlation was generally stronger between DEXA and serum biochemical markers of bone turnover or weight than between QUS and these parameters but was in the same direction. Mean hip bone density and QUS results were lower in the group of women with history of fractures than the others, 0.731+/-0.112 g/cm(2) vs. 0.779+/-0.130 g/cm(2) (T-score -1.18+/-1.18 vs. -1.61+/-1.20, p=0.001) and T-score -3.12+/-0.94 vs. -2.40+/-1.22 (p=0.0001) for QUS. Conclusions: Even though QUS is not a good test for diagnosing osteoporosis as defined by WHO criteria, it is a reasonable screening test with good sensitivity and fair specificity when using T-score of -2.5 as the cut-off point.Tilgangur: Að meta gildi ómunar (quantitative ultrasound, QUS) af hælbeini sem skimpróf fyrir beinþynningu. Inngangur: Hingað til hefur beinþéttnimæling með dual energy X-ray absorptiometry (DEXA) verið kjörrannsókn til greiningar á beinþynningu. DEXA krefst dýrs tækjabúnaðar og sérþekkingar. Ómun af hælbeini er ný rannsókn sem metur uppbyggingu beins. Talsvert misræmi er á milli DEXA og ómunar af hælbeini til greiningar á beinþynningu en hins vegar er ágætt samræmi milli niðurstaðna ómunar og tíðni beinbrota. Efniviður og aðferðir: Við rannsökuðum 297 sjötugar íslenskar konur. Allar fóru þær í DEXA mælingu af hrygg, mjöðm og lærleggshálsi og ómun af hælbeini. Við bárum saman fylgni og samræmi rannsóknaraðferðanna og mátum næmi og sértæki ómunar af hælbeini til greiningar á beinþynningu miðað við DEXA. Einnig reiknuðum við út fylgni við beinumsetningarvísa í blóði og þvagi. Að lokum var brotasaga kvennanna borin saman við beinþéttnimælingar. Niðurstöður: Fylgni þessara tveggja mæliaðferða var r=0,40-0,57 eftir því hvaða DEXA beinþéttnimælingu ómunin var borin saman við. Mesta fylgnin var við beinþéttni í mjöðm (nærenda lærleggs). Ef viðmiðunin var 2,5 staðalfrávik neðan við meðaltal ungra kvenna í DEXA (sem er skilmerki Alþjóðaheilbrigðisstofnunarinnar fyrir beinþynningu) kom í ljós að næmi ómunar af hælbeini miðað við beinþéttni í mjöðm var 91,7% og sértæki 49,0%. Jákvætt forspárgildi ómunar um beinþynningu í mjöðm samkvæmt DEXA var 25,8% en neikvætt forspárgildi var 96,8%. Samræmi rannsóknanna var reiknað út með kappa tölfræði og kom í ljós að k=0,25 sem þýðir að samræmi rannsóknanna er meira en tilviljun háð. Marktæk fylgni var við osteocalcin og Osteomark og á það við bæði DEXA og ómun af hælbeini. Sterk tengsl voru milli beinbrota og ómunar og DEXA. Ályktanir: Niðurstöður benda til þess að fylgni og samræmi ómunar af hælbeini og DEXA sé ekki mikil og því hæpið að nota ómun af hælbeini til greiningar á beinþynningu. Þar sem næmi ómunar af hælbeini er ágætt virðist hins vegar mega nota ómun til skimunar í hópi sem er í áhættu fyrir beinþynningu

Tetanus - A case report and literature review

Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Allur texti - Full textA 79 year old farmer was referred to the University Hospital with a three days history of difficulty in opening his mouth. On examination, both masseters were seen to be stiff, suggesting tetanus or jaw-subluxation. An attempt to reduce the joint was made, but failed. He subsequently developed progressive respiratory difficulties requiring intubation. The farmer had recently cut his finger on barbed wire. He had not received tetanus immunization for years and it was not clear whether primary immunization had been completed. Tetanus immunoglobulin and antibiotics were administered. He proceeded to develop autonomic instability and critical illness polyneuropathy requiring 45 days of ICU care. He was finally discharged eight months later. The farmer has gradually improved and is now living unaided at home. In this article we will review this case and the literature on tetanus. Correspondence: Albert Pall Sigurdsson, [email protected] Key words: Tetanus, case report.79 ára bónda var vísað á Landspítala þar sem hann hafði ekki getað opnað munninn í þrjá daga. Við skoðun voru tyggingarvöðvar spenntir. Talið var að þetta væri stífkrampi eða los á kjálkaliði. Reynt var að setja hann í lið án árangurs. Síðar bar á öndunarörðugleikum sem ágerðust. Bóndinn fór á gjörgæslu í öndunarvél. Hann hafði stungið sig í fingur á gaddavír við landbúnaðarstörf nokkru áður. Hann hafði ekki fengið stífkrampabólusetningu í mörg ár og óljóst var um grunnbólusetningu. Gefið var stífkrampa-ónæmisglóbúlín og sýklalyf. Síðar fékk hann truflun á ósjálfráða taugakerfinu auk gjörgæslu-úttaugameins. Hann lá 45 daga á gjörgæslu og útskrifaðist heim eftir 8 mánaða legu. Ástandið hefur lagast og er hann nú að mestu leyti sjálfbjarga. Í greininni er farið yfir tilfellið og gefið yfirlit yfir stífkrampa

Body Composition and Physical Fitness of Students in High School vs. Students Enrolled in High School Sports Academia Programs

In recent years more and more high schools in Iceland are offering sports academia programs. These programs are intended for teenage athletes in various sports who have the potential of becoming elite athletes. The sports academia programs make it easier for these student athletes to focus on training for their sport while attending high school, and thereby, enable them to get a good education and enhance their athletic potential. These programs also have the potential to reduce drop-out in sports because it is easier for the students to balance athletics and academics. Nevertheless, sports performance is not necessarily linked to better health. The purpose of this study was to compare students enrolled in regular high school tracks to students enrolled in sports academia programs on body composition and physical fitness

Modelling the 20th and 21st century evolution of Hoffellsjökull glacier, SE-Vatnajökull, Iceland

The Little Ice Age maximum extent of glaciers in Iceland was reached about 1890 AD and most glaciers in the country have retreated during the 20th century. A model for the surface mass balance and the flow of glaciers is used to reconstruct the 20th century retreat history of Hoffellsjökull, a south-flowing outlet glacier of the ice cap Vatnajökull, which is located close to the southeastern coast of Iceland. The bedrock topography was surveyed with radio-echo soundings in 2001. A wealth of data are available to force and constrain the model, e.g. surface elevation maps from ~1890, 1936, 1946, 1989, 2001, 2008 and 2010, mass balance observations conducted in 1936–1938 and after 2001, energy balance measurements after 2001, and glacier surface velocity derived by kinematic and differential GPS surveys and correlation of SPOT5 images. The approximately 20% volume loss of this glacier in the period 1895–2010 is realistically simulated with the model. After calibration of the model with past observations, it is used to simulate the future response of the glacier during the 21st century. The mass balance model was forced with an ensemble of temperature and precipitation scenarios derived from 10 global and 3 regional climate model simulations using the A1B emission scenario. If the average climate of 2000–2009 is maintained into the future, the volume of the glacier is projected to be reduced by 30% with respect to the present at the end of this century. If the climate warms, as suggested by most of the climate change scenarios, the model projects this glacier to almost disappear by the end of the 21st century. Runoff from the glacier is predicted to increase for the next 30–40 yr and decrease after that as a consequence of the diminishing ice-covered area

Diagnostic accuracy of 64-slice computed tomography compared with coronary angiography

Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/OpenObjective: The aim of this study was to evaluate the diagnostic accuracy (sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV)) of 64-slice multidetector computed tomography (MDCT) compared with quantitative coronary angiography (QCA) for detection of coronary artery disease (CAD). Material and methods: Sixty-nine patients participating in a study of coronary in-stent restenosis were investigated. After a 64-slice MDCT scan patients were evaluated by QCA. The coronary arteries were divided into 15 segments and stenosis was graded for each segment by both methods. The diagnostic accuracy of 64-slice MDCT was evaluated using the QCA as the gold standard. Results: Among the 69 patients included in the study 13 (19%) were female and 56 male. The mean age was 63 (SD 10) years. The following risk factors were present: high blood pressure 67%, elevated blood cholesterol 54%, diabetes 12% and family history of CAD 71%. Current smokers were 22% and previous smokers were 48%. Altogether 663 segments were examined. Of those 221 (33%) segments were excluded; 103 because of stents, 48 because of heavy calcification, 41 because of motion artifacts and 29 because the segments were less than 1.5 mm in diameter. The mean time between MDCT and QCA was 6.3 (SD 12.1) days. The sensitivity of 64-slice MDCT for diagnosing significant stenosis (>/= 50% according to QCA) was 20%, the specificity was 94%, PPV was 16%, NPV was 95% and the accuracy was 89%. Conclusion: High NPV and specificity indicates that MDCT is useful for accurately excluding significant CAD but the low sensitivity and low PPV indicate that the method is not accurate in diagnosing coronary artery stenosis of 50% or more according to QCA. Key words: coronary artery disease, multidetector computed tomography, cardiac catheterisation. Correspondence: Karl Andersen, [email protected]: Markmið rannsóknarinnar var að meta greiningarhæfni (næmi, sértæki, jákvætt forspárgildi, neikvætt forspárgildi og nákvæmni) 64 sneiða tölvusneiðmyndatækni (TS-tækni) á kransæðasjúkdómi með hjartaþræðingu sem viðmið. Efniviður og aðferðir: Rannsóknarhópurinn samanstóð af 69 sjúklingum sem tóku þátt í rannsókn á endurþrengslum í stoðnetum kransæða. Framkvæmd var TS af kransæðum til að meta æðaþrengsli. Nokkrum dögum síðar voru þátttakendur hjartaþræddir. Kransæðatrénu var skipt upp í 15 hluta. Æðaþrengsli voru metin í öllum hlutum æðatrésins með báðum aðferðunum. Greiningarhæfni 64 sneiða TS-tækni var metin og kransæðaþræðing höfð sem viðmið. Niðurstöður: Í rannsókninni voru 13 (19%) konur og 56 karlar. Meðalaldur þátttakenda var 63 (SD 10) ár, háþrýsting höfðu 67%, háar blóðfitur 54%, sykursýki 12% og ættarsaga um kransæðasjúkdóm var til staðar í 71% tilvika. Reykingamenn voru 22% og fyrrum reykingamenn 48%. Samtals 663 æðahlutar voru rannsakaðir. Af þeim voru 221 (33,4%) útilokaðir; 103 vegna stoðneta, 48 vegna truflana af völdum kalks, 41 vegna hreyfitruflana og 29 þar sem æðin var minni en 1,5 mm í þvermál. Meðaltími milli TS og hjartaþræðingar voru 6,3 (SD 12,1) dagar. Næmi 64 sneiða TS til greiningar marktækra þrengsla (?50% þrengsli samkvæmt hjartaþræðingu) var 20%, sértæki 94%, jákvætt forspárgildi 16%, neikvætt forspárgildi 95% og nákvæmni 89%. Ályktun: Hátt neikvætt forspárgildi og hátt sértæki gefur til kynna að TS-rannsókn sé gagnleg til að útiloka kransæðasjúkdóm. Lágt næmi og lágt jákvætt forspárgildi benda til að aðferðin sé ekki góð til að meta hvort kransæðaþrengsli séu 50% eða meiri við hjartaþræðingu

Markerless motion capture: What clinician-scientists need to know right now

National Institutes of Health R37-HD037985 provided tuition and stipend support for NI’s work. NIH R01-AR072034 provided stipend support for HBS and tuition and stipend support for KDS’s work. NIH F31-AR078580 and Foundation for Physical Therapy Research PODS II Scholarship provided tuition and stipend support for EKA's work.Peer reviewe

Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007

ABSTRACTGlaciers and ice caps around the world are changing quickly, with surge-type behaviour superimposed upon climatic forcing. Here, we study Iceland's second largest ice cap, Langjökull, which has both surge- and non-surge-type outlets. By differencing elevation change with surface mass balance, we estimate the contribution of ice dynamics to elevation change. We use DEMs, in situ stake measurements, regional reanalyses and a mass-balance model to calculate the vertical ice velocity. Thus, we not only compare the geodetic, modelled and glaciological mass balances, but also map spatial variations in glacier dynamics. Maps of emergence and submergence velocity successfully highlight the 1998 surge and subsequent quiescence of one of Langjökull's outlets by visualizing both source and sink areas. In addition to observing the extent of traditional surge behaviour (i.e. mass transfer from the accumulation area to the ablation area followed by recharge of the source area), we see peripheral areas where the surge impinged upon an adjacent ridge and subsequently retreated. While mass balances are largely in good agreement, discrepancies between modelled and geodetic mass balance may be explained by inaccurate estimates of precipitation, saturated adiabatic lapse rate or degree-day factors. Nevertheless, the study was ultimately able to investigate dynamic surge behaviour in the absence of in situ measurements during the surge.In situ mass balance survey is a joint effort of the Glaciology Group, Institute of Earth Sciences, University of Iceland and the National Power Company (Landsvirkjun). We thank Philippe Crochet and Tómas Jóhannesson from the Icelandic Meteorological Office for providing the gridded climate data and for useful discussions about the climatology of Langjökull. The 2007 lidar data were collected by the UK Natural Environment Research Council Airborne Research and Survey Facility (Grant IPY 07-08). Additional funding was provided by the United States National Science Foundation (Grant No. DGE-1038596), St Catharine’s, St John’s and Trinity Colleges and the University of Cambridge B.B. Roberts and Scandinavian Studies Funds. We thank Cameron Rye for initial help coding the mass balance model.This is the author accepted manuscript. The final version is available from Cambridge University Press via https://doi.org/10.1017/jog.2016.5