Inter- and intra-observer reliability of the new AO/OTA classification of proximal femur fractures.

INTRODUCTION: Hip fractures are a global health burden, with an incidence that is projected to increase from 66,000/year currently in the United Kingdom to 100,000/year by 2033. The classification of intertrochanteric fractures is key to the treatment algorithms advising on their surgical management. The AO/OTA classification is the most commonly used system, initially published in 1990 and subsequently shown to have poor inter- and intra-observer reliability, it was revised in 2018 with the main aim of re-classifying and further defining the 31-A2 group. METHODS: 150 plain film anteroposterior and lateral plain film radiographs of intertrochanteric fractures from three hospitals were classified using the 2018 AO/OTA classification of intertrochanteric fractures by six Orthopaedic Surgeons (2 Consultants, 4 Trainees), all were blinded to the definitive surgical treatment for patients. Radiographs were re-classified after a minimum of 3-months, Cohen's Kappa for inter-observer reliability was calculated from first round classifications and intra-observer reliability from first and second classifications. RESULTS: Mean Kappa for inter-observer reliability for AO group classification (e.g. 31-A1) was 0.479 (0.220 - 0.771, for sub-group classification (e.g. 31-A1.1) reliability reduced to 0.376 (0.276 - 0.613). Intra-observer reliability was comparable for both group and sub-group classifications, 0.661 and 0.587 respectively. CONCLUSIONS: The revised 2018 AO/OTA classification aimed to simply the classification of intertrochanteric fractures, however it remains unreliable with only a "moderate" inter-observer reliability at group level with this falling to "fair" when sub-group classifications are made. Identification of stable and unstable injuries using the new AO/OTA system remains fraught with difficulties and appears difficult to apply with consistent accuracy.

Burden of disease associated with dietary exposure to carcinogenic aflatoxins in Portugal using human biomonitoring approach.

Human biomonitoring is an important tool to assess human exposure to chemicals, contributing to describe trends of exposure over time and to identify population groups that could be under risk. Aflatoxins are genotoxic and carcinogenic food contaminants causing hepatocellular carcinoma, the third leading cause of cancer deaths worldwide. In Portugal, scarce data are available regarding exposure to aflatoxins and no previous study used human biomonitoring data to comprehensively characterize the associated burden of disease. 24 h urine and first-morning urine paired samples were collected by 94 participants and were analyzed by liquid chromatography-tandem mass spectrometry for the quantitative determination of aflatoxins (B1, B2, G1, G2 and M1). Deterministic and probabilistic models were developed to assess the Portuguese exposure to aflatoxins and to estimate the health impact of this exposure, estimating the attributed Disability-Adjusted Life Years (DALYs). Aflatoxins were detected in a maximum of 13% (AFB1), 16% (AFB2), 1% (AFG1), 2% (AFG2) and 19% (AFM1) of the urine samples. Data obtained through the probabilistic approach revealed an estimated mean probable daily intake of 13.43 ng/kg body weight per day resulting in 0.13 extra cases of hepatocellular carcinoma, corresponding to mean annual DALYs of 172.8 for the Portuguese population (10291027 inhabitants). The present study generated for the first time and within a human biomonitoring study, reliable and crucial data to characterize the burden associated to the exposure to aflatoxins of the Portuguese population. The obtained results constitute an imperative support to risk managers in the establishment of preventive policy measures that contribute to ensure public health protection.

Exposure assessment of Portuguese population to multiple mycotoxins: The human biomonitoring approach.

Mycotoxins constitute a relevant group of food contaminants with several associated health outcomes such as estrogenic, immunotoxic, nephrotoxic and teratogenic effects. Although scarce data are available in Portugal, human biomonitoring studies have been globally developed to assess the exposure to mycotoxins at individual level. In order to overcome this lack of data, the present study concerned the analysis of mycotoxins in 24h urine and first-morning urine paired samples from 94 participants enrolled within the scope of the National Food, Nutrition, and Physical Activity Survey of the Portuguese General Population (2015-2016). Following a salt-assisted matrix extraction, urine samples were analysed by liquid chromatography-mass spectrometry for the simultaneous determination of 37 urinary mycotoxins' biomarkers and data obtained used to estimate the probable daily intake as well as the risk characterization applying the Hazard Quotient approach. Results revealed the exposure of Portuguese population to zearalenone, deoxynivalenol, ochratoxin A, alternariol, citrinin and fumonisin B1 through the quantification in 24h urine and first-morning urine paired samples. Risk characterization data revealed a potential concern to some reported mycotoxins since the reference intake values were exceeded by some of the considered participants. Alternariol was identified for the first time in urine samples from a European country; however, risk characterization was not performed due to lack of reference intake value. These results confirmed mycotoxins as part of the human exposome of the Portuguese population reinforcing the need for further studies regarding the determinants of exposure.

Risk-Benefit Assessment of Foods.

Food is an elementary requirement for human life, providing nutrients and essential energy needed for optimal health. But at the same time, food can also be a vehicle of hazardous substances or pathogens that could affect human health negatively. Risk-benefit assessment (RBA) of foods, a relatively new methodology for decision support, integrates nutrition, toxicology, microbiology, chemistry and human epidemiology for a comprehensive health impact assessment. By integrating health risks and benefits related to food consumption, RBA facilitates science-based decision-making in food-related areas and the development of policies and consumer advice. The present work programme aimed to allow the fellow to become acquainted with the process of RBA and the associated tools needed to assess quantitatively the risks and the benefits through three main activities (i) to learn the different methodologies used for RBA; (ii) to apply these methodologies to a specific case-study - RBA of raw milk consumption; and (iii) to participate in the main activities of the Risk-Benefit research group at DTU Food regarding risk-benefit issues. For the RBA of raw milk consumption, microbiological pathogens (Listeria monocytogenes, Salmonella spp., Campylobacter jejuni and Shiga toxin-producing Escherichia coli), probiotic bacteria and nutritional components (vitamins B2 and A) were considered, as well as the potential impact of raw milk consumption in the reduction of the allergies' prevalence. Two major approaches were applied: the bottom-up (estimating the disease incidence due to the exposure) and the top-down (using epidemiological and incidence data to the estimate the number of cases attributable to a certain exposure). Through all the training and hands-on activities performed, the present work programme enabled the fellow to extend the knowledge on the quantitative RBA, specifically in the context of raw milk consumption. EU-FORA programme also provided an exceptional opportunity of networking and establishment of future research lines of collaboration.

Characterization of in vitro effects of patulin on intestinal epithelial and immune cells.

The intestinal mucosa is the first biological barrier encountered by natural toxins, and could possibly be exposed to high amounts of dietary mycotoxins. Patulin (PAT), a mycotoxin produced by Penicillium spp. during fruit spoilage, is one of the best known enteropathogenic mycotoxins able to alter functions of the intestine (Maresca et al., 2008). This study evaluated the effects of PAT on barrier function of the gut mucosa utilizing the intestinal epithelial cell model Caco-2, and scrutinized immunomodulatory effects using human peripheral blood mononuclear cells (PBMC) and human blood monocyte-derived dendritic cells (moDCs) as test systems. PAT exposure reduced Caco-2 cell viability at concentrations above 12µM. As expected, the integrity of a polarized Caco-2 monolayer was affected by PAT exposure, as demonstrated by a decrease in TER values, becoming more pronounced at 50µM. No effects were detected on the expression levels of the tight junction proteins occludin, claudin-1 and claudin-3 at 50µM. However, the expression of zonula occludens-1 (ZO-1) and myosin light chain 2 (MLC2) declined. Also, levels of phospho-MLC2 (p-MLC2) increased after 24h of exposure to 50µM of PAT. T cell proliferation was highly sensitive to PAT with major effects for concentrations above 10nM of PAT. The same conditions did not affect the maturation of moDC. PAT causes a reduction in Caco-2 barrier function mainly by perturbation of ZO-1 levels and the phosphorylation of MLC. Low doses of PAT strongly inhibited T cell proliferation induced by a polyclonal activator, but had no effect on the maturation of moDC. These results provide new information that strengthens the concept that the epithelium and immune cells of the intestinal mucosa are important targets for the toxic effects of food contaminants like mycotoxins.

Revision arthroplasty for periprosthetic femoral fracture using an uncemented modular tapered conical stem.

Periprosthetic femoral fracture (PFF) is a potentially devastating complication after total hip arthroplasty, with historically high rates of complication and failure because of the technical challenges of surgery, as well as the prevalence of advanced age and comorbidity in the patients at risk. This study describes the short-term outcome after revision arthroplasty using a modular, titanium, tapered, conical stem for PFF in a series of 38 fractures in 37 patients. The mean age of the cohort was 77 years (47 to 96). A total of 27 patients had an American Society of Anesthesiologists grade of at least 3. At a mean follow-up of 35 months (4 to 66) the mean Oxford Hip Score (OHS) was 35 (15 to 48) and comorbidity was significantly associated with a poorer OHS. All fractures united and no stem needed to be revised. Three hips in three patients required further surgery for infection, recurrent PFF and recurrent dislocation and three other patients required closed manipulation for a single dislocation. One stem subsided more than 5 mm but then stabilised and required no further intervention. In this series, a modular, tapered, conical stem provided a versatile reconstruction solution with a low rate of complications.

The relationship between operative and radiographic acetabular component orientation: which factors influence resultant cup orientation?

There is great variability in acetabular component orientation following hip replacement. The aims of this study were to compare the component orientation at impaction with the orientation measured on post-operative radiographs and identify factors that influence the difference between the two. A total of 67 hip replacements (52 total hip replacements and 15 hip resurfacings) were prospectively studied. Intra-operatively, the orientation of the acetabular component after impaction relative to the operating table was measured using a validated stereo-photogrammetry protocol. Post-operatively, the radiographic orientation was measured; the mean inclination/anteversion was 43° (sd 6°)/ 19° (sd 7°). A simulated radiographic orientation was calculated based on how the orientation would have appeared had an on-table radiograph been taken intra-operatively. The mean difference between radiographic and intra-operative inclination/anteversion was 5° (sd 5°)/ -8° (sd 8°). The mean difference between simulated radiographic and intra-operative inclination/anteversion, which quantifies the effect of the different way acetabular orientation is measured, was 3°/-6° (sd 2°). The mean difference between radiographic and simulated radiographic orientation inclination/anteversion, which is a manifestation of the change in pelvic position between component impaction and radiograph, was 1°/-2° (sd 7°). This study demonstrated that in order to achieve a specific radiographic orientation target, surgeons should implant the acetabular component 5° less inclined and 8° more anteverted than their target. Great variability (2 sd about ± 15°) in the post-operative radiographic cup orientation was seen. The two equally contributing causes for this are variability in the orientation at which the cup is implanted, and the change in pelvic position between impaction and post-operative radiograph.

Pelvic position and movement during hip replacement.

The orientation of the acetabular component is influenced not only by the orientation at which the surgeon implants the component, but also the orientation of the pelvis at the time of implantation. Hence, the orientation of the pelvis at set-up and its movement during the operation, are important. During 67 hip replacements, using a validated photogrammetric technique, we measured how three surgeons orientated the patient's pelvis, how much the pelvis moved during surgery, and what effect these had on the final orientation of the acetabular component. Pelvic orientation at set-up, varied widely (mean (± 2, standard deviation (sd))): tilt 8° (2sd ± 32), obliquity -4° (2sd ± 12), rotation -8° (2sd ± 14). Significant differences in pelvic positioning were detected between surgeons (p < 0.001). The mean angular movement of the pelvis between set-up and component implantation was 9° (sd 6). Factors influencing pelvic movement included surgeon, approach (posterior > lateral), procedure (hip resurfacing > total hip replacement) and type of support (p < 0.001). Although, on average, surgeons achieved their desired acetabular component orientation, there was considerable variability (2sd ± 16) in component orientation. We conclude that inconsistency in positioning the patient at set-up and movement of the pelvis during the operation account for much of the variation in acetabular component orientation. Improved methods of positioning and holding the pelvis are required.

Patient recall of surgical information after day case knee arthroscopy.

PURPOSE: Day case knee arthroscopy is frequently performed on dedicated lists designed to optimise the throughput of patients. This could affect patient recall of clinical information with clinical, ethical and medicolegal consequences. The purpose of this study was to assess patient recall after knee arthroscopy and identify potential contributory factors. METHODS: Seventy-two patients undergoing day case knee arthroscopy were provided with information about their surgery post-operatively and tested for recall of the information prior to discharge. All patients underwent cognitive assessment when information was delivered and again when tested. Patient recall was correlated with demographic and anaesthetic factors and a multivariate regression model was used to identify risk factors for reduced recall. RESULTS: Recall overall was poor. Significant independent risk factors for reduced recall were reduced cognitive state at the time of information delivery and a shorter time between surgery and information delivery. Duration of anaesthesia, use of sedatives and use of opiate analgesia were not significantly correlated with recall. CONCLUSIONS: Information recall after day case knee athroscopy may be suboptimal. Allowing more time between surgery and information delivery may improve recall. However, this may be difficult during the course of a busy list and surgeons should consider using additional techniques to improve patient recall after surgery to reduce the risk of patient anxiety or non-compliance. LEVEL OF EVIDENCE: IV.

The limits of precision in conventionally instrumented computer-navigated total knee arthroplasty.

PURPOSE: Computer-navigated total knee arthroplasty (TKA) improves the accuracy of component implantation. However, the final implant alignment may not match planned alignment. The hypothesis of this study is that although computer navigation improves alignment, imprecision may not be completely eliminated. The aim of the study was to establish the incidence and sources of imprecision during TKA using computer navigation to measure deviations from planned alignment. METHODS: Computer navigation was used to quantify changes in planned alignment at four steps during 136 TKA's: application of cutting blocks, addition of definitive pin fixation, bone cuts and after prosthesis application. Mean changes in alignment deviation at each step in each plane were measured and the number of significant outliers (>3° from the planned resection plane) were assessed in each plane. RESULTS: Overall changes in planned alignment were small and non-cumulative between steps but the incidence of outliers (cuts measured as >3° from planned alignment at each step) increased through the steps, with 21.3 % (n = 29) of final implants outlying in the tibial sagittal plane, which was the least precise plane. The highest number of outliers occurred after bone resection and the addition of pins to cutting blocks was also identified as a source of imprecision. CONCLUSION: Despite improved accuracy of bone resection with computer-navigated TKA, the precision of bone cuts may be affected at several steps of the procedure. Cutting block application, bone resection and prosthesis application may all affect accuracy. Bone cuts should be made with meticulous care, whether navigated or not, and navigated cuts should be checked and corrected, particularly in the tibial sagittal plane. LEVEL OF EVIDENCE: IV.

Fast detection of arbitrarily shaped disease clusters.

Disease cluster detection and evaluation have commonly used spatial statistics methods that scan the map with a fixed circular window to locate candidate clusters. Recently, there has been interest in searching for clusters with arbitrary shape. The circular scan test retains high power of detecting a cluster, but does not necessarily identify the exact regions contained in a non-circular cluster particularly well. We propose, implement and evaluate a new procedure that is fast and produces clusters estimates of arbitrary shape in a rich class of possible cluster candidates. We showed that our methods contain the so-called upper level set method as a particular case. We present a power study of our method and, among other results, the main conclusion is that the likelihood-based arbitrarily shaped scan method is not appropriate to find a cluster estimate. When the parameter space includes the set of all possible spatial clusters in a map, a large and discrete parameter space, maximum likely cluster estimates tend to overestimate the true cluster by a large extent. This calls for a new approach different from the maximum likelihood method for this important public health problem.

Segmental fracture of the scaphoid: report of a rare fracture pattern.

INTRODUCTION: To the best of our knowledge, there are no reports in the orthopaedic and trauma literature of true segmental fracture of the scaphoid bone. We present such a case with a brief discussion of the morphology and mechanisms of injury of scaphoid fractures and the problems they present, particularly in diagnosis. CASE HISTORY: A 43-year-old male with polytrauma sustained in a motorcycle road traffic accident was treated at our hospital. His injuries included a fracture initially thought to involve the waist of the scaphoid. Because he had bilateral upper limb injuries, we elected to treat the fracture surgically to facilitate rehabilitation. At the time of surgery, the fracture was noted to be truly segmental, an unsuspected and rare finding. The fracture was internally fixed, with a satisfactory result. DISCUSSION: Scaphoid fracture patterns are generally consistent and predictable, occurring most commonly through the waist of the bone. Mechanism for injury is thought to be hyperextension of the wrist. Comminution, with or without a butterfly fragment, is occasionally seen, as are simultaneous tuberosity fractures. We suggest that the mechanism in this case may have been multiple or secondary trauma, or an effect of loaded rotation. We highlight the need for careful imaging of the scaphoid bone prior to choosing treatment.

Spatial distribution of the Human T-Lymphotropic Virus types I and II (HTLV-I/II) infection among blood donors of Hemominas Foundation, Belo Horizonte, Minas Gerais State, Brazil, 1994-1996.

We conducted a cross-sectional study of the spatial distribution of HTLV-I/II infection among blood donors of Hemominas Foundation, living in Belo Horizonte, from 1994 to 1996. Study population (1,022) was composed by 533 cases (positive Western Blot (WB), indeterminate WB and ELISA positive without WB result) and a random sample of 489 non-cases (HTLV-I/II serum negative). Cases and non-cases were georeferenced using the exact or an approximation of the household address reported at the blood donation interview. Using multivariate analysis, cases with WB result are less likely to be reposition blood donors compared to voluntary ones (OR = 0.70; CI 95%: 0.50-0.99). Using the difference between univariate K functions, we found no evidence that cases and non-cases differ in their spatial distribution. We found no evidence that cases with and without WB result differ in the distance between their residence and Hemominas Foundation. No donors without WB result were georeferenced by the exact address. These donors could not have received the Hemominas letter inviting them to return to collect the second blood sample.

Spatial distribution of human and canine visceral leishmaniasis in Belo Horizonte, Minas Gerais State, Brasil, 1994-1997.

In this paper, we present spatial analysis of the association between all incidents cases of human Visceral Leishmaniasis and seropositive dogs, from 1994 to 1997 in Belo Horizonte, a large Brazilian city. We geocoded 158 human cases and 11,048 seropositive dogs and compared canine prevalence rates with Human Bayesian Incidence rates in the same areas. We also used Knox's test to evaluate the hypothesis of space-time clustering of human cases in the period. Additionally, we used Kernel's maps for seropositive dogs distribution and located the human cases in the resulting smooth maps. We concluded that human and dog rates are correlated. Also, the Visceral Leishmaniasis in Belo Horizonte spread quickly, but apart from the rates' magnitude, it has kept the same spatial pattern through time. We believe it is possible to use this technique to choose areas to implement control measures against Visceral Leishmaniasis in a more efficient way.

[Homicide clusters and drug traffic in Belo Horizonte, Minas Gerais State, Brazil from 1995 to 1999]. / Conglomerados de homicídios e o tráfico de drogas em Belo Horizonte, Minas Gerais, Brasil, de 1995 a 1999.

The article presents a spatial analysis of homicides in Belo Horizonte according to the Minas Gerais Military Police records from 1995 to 1999. The authors identify clusters of high mortality risk and relate them to areas with drug traffic and associated violence. SaTScan software is used to locate the clusters.

Diffusion and prediction of Leishmaniasis in a large metropolitan area in Brazil with a Bayesian space-time model.

We present results from an analysis of human visceral Leishmaniasis cases based on public health records of Belo Horizonte, Brazil, from 1994 to 1997. The main emphasis in this study is on the development of a spatial statistical model to map and project the rates of visceral Leishmaniasis in Belo Horizonte. The model allows for space-time interaction and it is based on a hierarchical Bayesian approach. We assume that the underlying rates evolve in time according to a polynomial trend specific to each small area in the region. The parameters of these polynomials receive a spatial distribution in the form of an autonormal distribution. While the raw rates are extremely noisy and inadequate to support decisions, the resulting smoothed rates estimates are considerably less affected by small area issues and provide very clear directions to implement public health actions.

American cutaneous leishmaniasis in Southeast Brazil: space-time clustering.

BACKGROUND: American cutaneous leishmaniasis (ACL) is endemic in many rural areas of Brazil where different transmission patterns of the disease have been described. This ecological study was carried out in a municipality located in Southeast Brazil and aimed to investigate the space-temporal patterns of the disease and environmental risk factors from 1966 to 1996. METHODS: Incident ACL cases were defined by clinical diagnosis, confirmed by a positive skin test and/or parasitological examination. Age-adjusted morbidity rate of ACL was calculated by year for this municipality and their different census enumeration districts. The homogeneity chi2 test, Moran and empirical Bayes index and Knox procedure were employed for testing the significance of clusters in time, space and in time-space, respectively. A Poisson regression model was used to identify environmental factors related to rate variability. RESULTS: A total of 1712 new ACL cases were reported with a yearly incidence rate of 48/100000 inhabitants. Higher incidence rates were detected in 1968, 1974, and 1988 (100, 160, and 190 cases/100000, respectively) with evidence of spatial clustering from 1986 to 1993. Significant space-time clustering with epidemic peaks followed by low incidence in subsequent periods was observed. The incidence rates of ACL were independently associated with rural areas; areas lacking sanitary installations and with higher proportion of exposed garbage (P < 0.01). CONCLUSIONS: This study suggests that ACL rates vary across space and time. Rural areas and some environmental factors could explain part of this variation. Environmental modifications in the vicinity of households over time and accumulation of susceptible individuals are discussed as possible factors responsible for variability.

PIP: This paper presents the results of an ecological study on American cutaneous leishmaniasis (ACL) cases carried out in Caratinga municipality, Southeast Brazil. The study aimed to estimate the incidence rates of ACL from 1966 to 1996, to test for space and temporal patterns in the rates and to correlate them to sociogeographic factors. Findings of the study showed an increase in the incidence rates of reported ACL cases. A total of 1712 ACL cases were reported in Caratinga during 1966-96, with a yearly incidence rate of 48/100,000 inhabitants. Evidence of spatial clustering was noted during 1986-93. Higher incidence rates were detected in 1968 (100 cases/100,000 inhabitants), 1974 (160/100,000), and 1988 (190/100,000). In addition, an observation noted that explosive outbreaks of ACL are followed with very low incident rate cases in the subsequent period. This observation indicates a lifelong resistance for treated individuals following clinically apparent infection. Moreover, prevalence of ACL infection was associated with rural areas, lack of sanitary disposal, and exposed garbage.

A new proposal to adjust Moran's I for population density.

We analyse the effect of using prevalence rates based on populations with different sizes in the power of spatial independence tests. We compare the well known spatial correlation Moran's index to three indexes obtained after adjusting for population density, one proposed by Oden, another proposed by Waldhör, and a third proposed by us in this paper. We find an effect of spatially correlated populations in the type I error probability on the test based on Moran's and Waldhör's indexes. We conclude also that the test proposed by Oden is powerful to test risk heterogeneity, but it has disadvantages when the interest is solely on the spatial correlation of morbidity risks. In this latter case, we recommend using our proposed test which is more powerful than the usual Moran's index applied directly to the rates.

[Management of AIDS during traditional hospitalization and at outpatient clinics in Recife (Brazil)]. / Prise en charge du sida en hospitalisations traditionnelle et de jour à Recife (Brésil).

The management of 50 AIDS patients by traditional hospital admission (25 cases) and outpatient clinics (25 cases) was studied between August and November 1995 in the Department of Infectious and Parasitic Diseases of the Federal University Hospital. The most costly items of expenditure were hospital services and consumable materials. Comparison of costs was complicated by differences in clinical status of the patients in the two groups. The choice of treatment was much more dependent on clinical status than on sociodemographic factors. Traditional hospital admission tended to be associated with the poorest patients. The rationalization of care based on cost-benefit analysis requires much future work.

[Maps of epidemiological rates: a Bayesian approach]. / Mapas de taxas epidemiológicas: uma abordagem Bayesiana.

This article presents statistical methods recently developed for the analysis of maps of disease rates when the geographic units have small populations at risk. They adopt the Bayesian approach and use intensive computational methods for estimating risk in each area. The objective of the methods is to separate the variability of rates due to differences between regions from the background risk due to pure random fluctuation. Risk estimates have a total mean quadratic error smaller than usual estimates. We apply these new methods to estimate infant mortality risk in the municipalities of the State of Minas Gerais in 1994.