Is there a need for routine follow-up after primary total hip arthroplasty?

Background: The objective of routine outpatient assessment of well functioning patients after primary total hip arthroplasty (THA) is to detect asymptomatic failure of prostheses to guide recommendations for early intervention. We have observed that the revision of THAs in asymptomatic patients is highly uncommon. We therefore question the need for routine follow-up of patients after THA. Methods: A prospective analysis of an orthopaedic database identified 158 patients who received 177 revision THAs over a 4 year period. A retrospective chart review was conducted. Patient demographics, primary and revision surgery parameters and follow-up information was recorded and cross referenced with AOA NJRR data. Results: 110 THAs in 104 patients (average age 70.4 (SD 9.8 years). There were 70 (63.6%) total, 13 (11.8%) femoral and 27 (24.5%) acetabular revisions. The indications for revision were aseptic loosening (70%), dislocation (8.2%), peri-prosthetic fracture (7.3%), osteolysis (6.4%) and infection (4.5%). Only 4 (3.6%) were asymptomatic revisions. A mean of 5.3 (SD 5.2 and 1.9 (SD 5.3 follow-up appointments were required before revision in patients with and without symptoms, respectively. The average time from the primary to revision surgery was 11.8 (SD 7.23) years. Conclusions: We conclude that patients with prostheses with excellent long term clinical results as validated by Joint Registries, routine follow-up of asymptomatic THA should be questioned and requires further investigation. Based on the work of this study, the current practice of routine follow-up of asymptomatic THA may be excessively costly and unnecessary and a less resource-intensive review method may be more appropriate.

Application of data mining techniques in the prediction of coronary artery disease : use of anaesthesia time-series and patient risk factor data

The high morbidity and mortality associated with atherosclerotic coronary vascular disease (CVD) and its complications are being lessened by the increased knowledge of risk factors, effective preventative measures and proven therapeutic interventions. However, significant CVD morbidity remains and sudden cardiac death continues to be a presenting feature for some subsequently diagnosed with CVD. Coronary vascular disease is also the leading cause of anaesthesia related complications. Stress electrocardiography/exercise testing is predictive of 10 year risk of CVD events and the cardiovascular variables used to score this test are monitored peri-operatively. Similar physiological time-series datasets are being subjected to data mining methods for the prediction of medical diagnoses and outcomes. This study aims to find predictors of CVD using anaesthesia time-series data and patient risk factor data. Several pre-processing and predictive data mining methods are applied to this data. Physiological time-series data related to anaesthetic procedures are subjected to pre-processing methods for removal of outliers, calculation of moving averages as well as data summarisation and data abstraction methods. Feature selection methods of both wrapper and filter types are applied to derived physiological time-series variable sets alone and to the same variables combined with risk factor variables. The ability of these methods to identify subsets of highly correlated but non-redundant variables is assessed. The major dataset is derived from the entire anaesthesia population and subsets of this population are considered to be at increased anaesthesia risk based on their need for more intensive monitoring (invasive haemodynamic monitoring and additional ECG leads). Because of the unbalanced class distribution in the data, majority class under-sampling and Kappa statistic together with misclassification rate and area under the ROC curve (AUC) are used for evaluation of models generated using different prediction algorithms. The performance based on models derived from feature reduced datasets reveal the filter method, Cfs subset evaluation, to be most consistently effective although Consistency derived subsets tended to slightly increased accuracy but markedly increased complexity. The use of misclassification rate (MR) for model performance evaluation is influenced by class distribution. This could be eliminated by consideration of the AUC or Kappa statistic as well by evaluation of subsets with under-sampled majority class. The noise and outlier removal pre-processing methods produced models with MR ranging from 10.69 to 12.62 with the lowest value being for data from which both outliers and noise were removed (MR 10.69). For the raw time-series dataset, MR is 12.34. Feature selection results in reduction in MR to 9.8 to 10.16 with time segmented summary data (dataset F) MR being 9.8 and raw time-series summary data (dataset A) being 9.92. However, for all time-series only based datasets, the complexity is high. For most pre-processing methods, Cfs could identify a subset of correlated and non-redundant variables from the time-series alone datasets but models derived from these subsets are of one leaf only. MR values are consistent with class distribution in the subset folds evaluated in the n-cross validation method. For models based on Cfs selected time-series derived and risk factor (RF) variables, the MR ranges from 8.83 to 10.36 with dataset RF_A (raw time-series data and RF) being 8.85 and dataset RF_F (time segmented time-series variables and RF) being 9.09. The models based on counts of outliers and counts of data points outside normal range (Dataset RF_E) and derived variables based on time series transformed using Symbolic Aggregate Approximation (SAX) with associated time-series pattern cluster membership (Dataset RF_ G) perform the least well with MR of 10.25 and 10.36 respectively. For coronary vascular disease prediction, nearest neighbour (NNge) and the support vector machine based method, SMO, have the highest MR of 10.1 and 10.28 while logistic regression (LR) and the decision tree (DT) method, J48, have MR of 8.85 and 9.0 respectively. DT rules are most comprehensible and clinically relevant. The predictive accuracy increase achieved by addition of risk factor variables to time-series variable based models is significant. The addition of time-series derived variables to models based on risk factor variables alone is associated with a trend to improved performance. Data mining of feature reduced, anaesthesia time-series variables together with risk factor variables can produce compact and moderately accurate models able to predict coronary vascular disease. Decision tree analysis of time-series data combined with risk factor variables yields rules which are more accurate than models based on time-series data alone. The limited additional value provided by electrocardiographic variables when compared to use of risk factors alone is similar to recent suggestions that exercise electrocardiography (exECG) under standardised conditions has limited additional diagnostic value over risk factor analysis and symptom pattern. The effect of the pre-processing used in this study had limited effect when time-series variables and risk factor variables are used as model input. In the absence of risk factor input, the use of time-series variables after outlier removal and time series variables based on physiological variable values’ being outside the accepted normal range is associated with some improvement in model performance.

HCI & sustainable food culture : a design framework for engagement

The current food practices around the world raises concerns for food insecurity in the future. Urban / suburban / and peri-urban environments are particularly problematic in their segregation from rural areas where the natural food sources are grown and harvested. Soaring urban population growth only deteriorates the lack of understanding in and access to fresh produce for the people who live, work, and play in the city. This paper explores the role of Human-Computer Interaction (HCI) design in encouraging individual users to participate in creating sustainable food cultures in urban environments. The paper takes a disciplinary perspective of urban informatics and presents five core constituents of the HCI design framework to encourage sustainable food culture in the city via ubiquitous technologies: the perspective of transdisciplinarity; the domains of interest of people, place, and technology; and the perspective of design.

Diarrhoea risk factors in enterally tube fed critically ill patients : a retrospective audit

Objective: Diarrhoea in the enterally tube fed (ETF) intensive care unit (ICU) patient is a multifactorial problem. Diarrhoeal aetiologies in this patient cohort remain debatable; however, the consequences of diarrhoea have been well established and include electrolyte imbalance, dehydration, bacterial translocation, peri anal wound contamination and sleep deprivation. This study examined the incidence of diarrhoea and explored factors contributing to the development of diarrhoea in the ETF, critically ill, adult patient. ---------- Method: After institutional ethical review and approval, a single centre medical chart audit was undertaken to examine the incidence of diarrhoea in ETF, critically ill patients. Retrospective, non-probability sequential sampling was used of all emergency admission adult ICU patients who met the inclusion/exclusion criteria. ---------- Results: Fifty patients were audited. Faecal frequency, consistency and quantity were considered important criteria in defining ETF diarrhoea. The incidence of diarrhoea was 78%. Total patient diarrhoea days (r = 0.422; p = 0.02) and total diarrhoea frequency (r = 0.313; p = 0.027) increased when the patient was ETF for longer periods of time. Increased severity of illness, peripheral oxygen saturation (Sp02), glucose control, albumin and white cell count were found to be statistically significant factors for the development of diarrhoea. ---------- Conclusion: Diarrhoea in ETF critically ill patients is multi-factorial. The early identification of diarrhoea risk factors and the development of a diarrhoea risk management algorithm is recommended.

Designing for engagement towards healthier lifestyles through food image sharing : the case of I8DAT

This paper introduces the underlying design concepts of I8DAT, a food image sharing application that has been developed as part of a three-year research project – Eat, Cook, Grow: Ubiquitous Technology for Sustainable Food Culture in the City (http://www.urbaninformatics .net/projects/food) – exploring urban food practices to engage people in healthier, more environmentally and socially sustainable eating, cooking, and growing food in their everyday lives. The key aim of the project is to produce actionable knowledge, which is then applied to create and test several accessible, user-centred interactive design solutions that motivate user-engagement through playful and social means rather than authoritative information distribution. Through the design and implementation processes we envisage to integrate these design interventions to create a sustainable food network that is both technical and socio-cultural in nature (technosocial). Our primary research locale is Brisbane, Australia, with additional work carried out in three reference cities with divergent geographic, socio-cultural, and technological backgrounds: Seoul, South Korea, for its global leadership in ubiquitous technology, broadband access, and high population density; Lincoln, UK, for the regional and peri-urban dimension it provides, and Portland, Oregon, US, for its international standing as a hub of the sustainable food movement.

The role of transport infrastructure in facilitating the survival and growth of micro-enterprises in developing economies

Transport and logistics are essential to effective business. Very little is currently known about the impact of improved transport on micro-enterprises in developing economies and whether improvements in this area would assist the very poor. This paper looks at the obstacles of an inefficient transport facilitation system and the high costs incurred by 22 survival micro-entrepreneurs funded by the same local NGO and operating in diverse industry sectors in a peri-urban context in Mozambique. Six case studies are selected to illustrate the most common constraints they face. The perspectives of the micro-business owners are confronted with those of government officials and community leaders for two reasons: to identify any mismatch and to discuss possible solutions. Significant discrepancies are detected between government agenda and needs of the population, while community-based entrepreneurship (CBE) is discussed as a possible collective strategy in dealing with the problem.

Improving Indigenous women’s wellness through action research

Today in Australia, 75% of all Indigenous Australians reside in urban and peri-urban areas. In Brisbane, Indigenous Australians now number just over 45,000, and this number is rapidly increasing. Undertaking research with urban based Indigenous Australians is a relatively new phenomenon. Most past research with Indigenous people has been carried out in remote and regional areas. This paper focuses on a Participation Action Research project undertaken with Indigenous women in the highly urbanised area of North Brisbane. The project takes on the challenge of undertaking urban based Indigenous research. It opts not to centre on poor Indigenous women’s health statistics but instead centres on Indigenous women’s wellness and ways to talk about and work towards wellness. Through the cycles of dialogue with Indigenous women these concepts were teased out and manifested in two highly successful Women’s Wellness Summits. This paper will outline aspects of this project.

Re-cementing in revision total hip replacement

Removal of well-fixed cement at revision surgery risks bone loss, cortical perforation and fracture, is time-consuming, technically demanding and carries increased risks for the patient. The cement-in-cement technique avoids these problems and when used appropriately has given favourable results at our centre when used on both the femoral and acetabular sides of the articulation. A modified technique has also been used in selected cases of infection and peri-prosthetic fracture. This chapter highlights the results to date and the operative techniques employed. It is essential to recognise that this technique relies fundamentally on the presence of a well-fixed cement mantle, and it is imperative that the criteria laid out are adhered to in order to achieve success. If there is loosening or lysis on the femoral side extending distal to the lesser trochanter or around more than just the periphery of the acetabular cement mantle, then alternative revision techniques should be employed.

Complications related to therapeutic anticoagulation in total hip arthroplasty

Bleeding related wound complications cause significant morbidity in lower limb arthroplasty surgery. Patients who require therapeutic anticoagulation in the peri operative period are potentially at higher risk of these complications. This is a retrospective case control study reviewing all primary total hip replacements performed in a single center over a five year period and comparing outcomes of the patients on warfarin with a double-matched control group of patients not on warfarin. The warfarin group had significantly higher risk of deep joint infection (9% vs 2.2%), haematoma/ wound ooze (28% vs 4%) and superficial infection (13.5% vs 2.2%). Managing the total hip arthroplasty patient with therapeutic anticoagulation is a balance between the risk of thromboembolic disease and bleeding related complications. Improved understanding of this risk will better allow the patient to make an informed decision regarding their elective arthroplasty surgery.

Micro-credit is not sufficient for the success of micro-enterprises at the bottom of the pyramid

This study examines the factors affecting the successful provision of micro-credit to people at the bottom of the pyramid and discusses the activities required to support entrepreneurial activities in a peri-urban African setting. The findings enable us to better understand why micro-credit, though useful, is only part of the solution, in a setting characterized by extreme resource constraints with an institutional fabric lacking the infrastructure that assists market development. We depict the crafting of new entrepreneurial activity as an ongoing process and present an emerging research agenda for future developments.

Quality of life for older people in residential care is related to connectedness, willingness to enter care, and co-residents

Aim: To establish associations with quality of life (QOL) of older people in long-term residential care facilities in two New Zealand cities. Methods: The outcome measure of QOL was the Life Satisfaction Index. We used multiple linear regression to explore how broad categories of factors might contribute to QOL. Results: A total of 599 people (median age of 85 years; 74% women) participated. Response rates were 85% for facilities and 83% for residents. A resident's QOL was significantly related to the QOL of co-residents. QOL was higher for people who were more positive about entry to residential care, more physically able, and not depressed, and for those with more family and emotional support. Conclusion: Attending to the circumstances around entry to residential care may enhance QOL, as may promoting physical activity, treating depression and ensuring older people remain emotionally connected to their families. In choosing a facility, noting the QOL of co-residents is important.

Home-based activity program for older people with depressive symptoms: DeLLITE–A randomized controlled trial

PURPOSE We wanted to assess the effectiveness of a home-based physical activity program, the Depression in Late Life Intervention Trial of Exercise (DeLLITE), in improving function, quality of life, and mood in older people with depressive symptoms. METHODS We undertook a randomized controlled trial involving 193 people aged 75 years and older with depressive symptoms at enrollment who were recruited from primary health care practices in Auckland, New Zealand. Participants received either an individualized physical activity program or social visits to control for the contact time of the activity intervention delivered over 6 months. Primary outcome measures were function, a short physical performance battery comprising balance and mobility, and the Nottingham Extended Activities of Daily Living scale. Secondary outcome measures were quality of life, the Medical Outcomes Study 36-item short form, mood, Geriatric Depression Scale (GDS-15), physical activity, Auckland Heart Study Physical Activity Questionnaire, and self-report of falls. Repeated measures analyses tested the differential impact on outcomes over 12 months’ follow-up. RESULTS The mean age of the participants was 81 years, and 59% were women. All participants scored in the at–risk category on the depression screen, 53% had a Diagnostic and Statistical Manual of Mental Disorders or International Classification of Diseases, Tenth Revision diagnosis of major depression or scored more than 4 on the GDS-15 at baseline, indicating moderate or severe depression. Almost all participants, 187 (97%), completed the trial. Overall there were no differences in the impact of the 2 interventions on outcomes. Mood and mental health related quality of life improved for both groups. CONCLUSION he DeLLITE activity program improved mood and quality of life for older people with depressive symptoms as much as the effect of social visits. Future social and activity interventions should be tested against a true usual care control.

Phosphorus as a limiting factor on sustainable greywater irrigation

Water reuse through greywater irrigation has been adopted worldwide and has been proposed as a potential sustainable solution to increased water demands. Despite widespread adoption there is limited domestic knowledge of greywater reuse, there is no pressure to produce lowlevel phosphorus products and current guidelines and legislation, such as those in Australia, may be inadequate due to the lack of long-term data to provide a sound scientific basis. Research has clearly identified phosphorus as a potential environmental risk to waterways from many forms of irrigation. To assess the sustainability of greywater irrigation, this study compared four residential lots that had been irrigated with greywater for four years and adjacent non-irrigated lots that acted as controls. Each lot was monitored for the volume of greywater applied and selected physic-chemical water quality parameters and soil chemistry profiles were analysed. The non-irrigated soil profiles showed low levels of phosphorus and were used as controls. The Mechlich3 Phosphorus ratio (M3PSR) and Phosphate Environmental Risk Index (PERI) were used to determine the environmental risk of phosphorus leaching from the irrigated soils. Soil phosphorus concentrations were compared to theoretical greywater irrigation loadings. The measured phosphorus soil concentrations and the estimated greywater loadings were of similar magnitude. Sustainable greywater reuse is possible; however incorrect use and/or a lack of understanding of how household products affect greywater can result in phosphorus posing a significant risk to the environment.