Variation in rates of hip and knee joint replacement in Australia based on socio-economic status, geographical locality, birthplace and indigenous status

Does neighbourhood deprivation influence low back pain and arthritis: An empirical study using multilevel twin design

OBJECTIVE

Neighbourhood deprivation has been found to be associated with many health conditions, but its association with low back pain (LBP) and arthritis is unclear. This study aimed to examine the association between neighbourhood deprivation with LBP and arthritis, and its potential interaction with individual socioeconomic status (SES) on these outcomes.

METHODS

Monozygotic (MZ) twins from the Washington State Twin Registry were used to control for genetic and common environmental factors that could otherwise confound the purported relationship. Multilevel models were employed to examine the association between neighbourhood deprivation as well as individual-level SES with LBP/arthritis, adjusting for age, sex, body mass index (BMI) and residence rurality.

RESULTS

There were 6,380 individuals in the LBP sample and 2,030 individuals in the arthritis sample. Neighbourhood deprivation was not associated with LBP (P = 0.26) or arthritis (P = 0.61), and neither was its interaction with individual-level SES. People without a bachelor's degree were more likely to report LBP (OR 1.44, 95% CI 1.26-1.65) or both LBP and arthritis (OR 1.67, 95% CI 1.14-2.45) than those with a bachelor's degree, but not for arthritis alone (P = 0.17). Household income was not significantly associated with LBP (P = 0.16) or arthritis (p = 0.23) independent of age, sex, and BMI.

CONCLUSION

Our study did not find significant associations between neighbourhood deprivation and the presence of LBP or arthritis. More research using multilevel modelling to investigate neighbourhood effects on LBP and arthritis is recommended.

Total joint replacement may be a valuable treatment for Aboriginal and Torres Strait Islander people with osteoarthritis, but uptake is low

BACKGROUND

Despite bearing a higher burden of osteoarthritis, little research has examined disparities in the access, utilisation and surgical outcomes associated with total joint replacement (TJR) among Aboriginal and Torres Strait Islander people.

METHODS

We conducted a retrospective cohort study to compare the sociodemographic and clinical characteristics of all Aboriginal and Torres Strait Islander and non-Aboriginal patients who underwent primary hip and knee replacement at St Vincent's Hospital Melbourne between 1996 and 2019.

RESULTS

A total of 10 277 primary total knee or hip replacements were performed in the 1996-2019 study period, of which 49 (0.5%) patients identified as either Aboriginal and/or Torres Strait Islander. Aboriginal and Torres Strait Islander patients were younger (61.7 ± 11.8 vs. 68.3 ± 10.3 years; P < 0.001), recorded higher Body Mass Index scores (median (IQR), 36.0 (29.5-41.4) vs. 30.8 (27.0-35.3); P < 0.001) and were more likely to experience multiple co-morbidities at the time of surgery. Despite these findings, Aboriginal and Torres Strait Islander patients did not experience higher complication rates and experienced comparable, clinically meaningful quality of life improvements 12-months post-surgery.

CONCLUSIONS

TJR appears to be a valuable treatment option for Aboriginal and Torres Strait Islander people with end-stage osteoarthritis. Our study was limited by the small number of procedures conducted in patients who identify as Aboriginal and Torres Strait Islander. Further research is needed to understand why uptake of TJR by Aboriginal and Torres Strait Islander people is low.

Staying moving, staying strong: Protocol for developing culturally appropriate information for Aboriginal people with osteoarthritis, rheumatoid arthritis, lupus and gout

Introduction

Addressing disparities in arthritis care is an important yet unmet health need for Aboriginal and Torres Strait Islander people in Australia (respectfully Aboriginal people herewith). Despite the significant prevalence and burden of arthritis within Aboriginal communities, access to care for arthritis is low. One means to reduce existing disparities in health care is to address current challenges relating to the appropriateness and acceptability of health care information resources for Aboriginal people. Health information sources can help to empower patients and their families to have greater involvement in their care and to engage in self-management of their condition. Despite an extensive range of arthritis information resources being available, currently no resources have been culturally adapted and developed in collaboration with Aboriginal consumers with arthritis. This paper outlines the processes that will be undertaken within the Staying Moving, Staying Strong project. This project aims to develop culturally secure arthritis information for Aboriginal people with osteoarthritis, rheumatoid arthritis, lupus and gout.

Methods and analysis

The overarching principle guiding this project is cultural security, referring to the incorporation of processes such that the research will not compromise the cultural rights, values and expectations of Aboriginal people. This project will prioritise partnerships, community engagement, community benefit, sustainability, transferability, and capacity building and therefore uphold the cultural rights and values of Aboriginal people. In this six-phase project we will; 1) Establish a community reference group and advisory committee; 2) Explore the health information needs and preferences of Aboriginal people with arthritis; 3) Synthesise the existing key recommendations in high quality clinical practice guidelines on arthritis care; 4) Culturally adapt key clinical recommendations; 5) Develop culturally appropriate arthritis resources and; 6) Qualitatively evaluate the developed resources.

Addressing surgical inequity for Aboriginal and Torres Strait Islander people in Australia's universal health care system: a call to action

Aboriginal and Torres Strait Islander people continue to experience health inequity within the Australian health care system. Little research has examined how disparities in surgical care access and outcomes contribute to Aboriginal health. In this narrative review and call to action, we discuss five care points along the journey to high-quality surgical care: health care seeking, primary health care services, specialist services, surgery and surgical outcomes. We highlight barriers and disparities that exist along this journey, drawing examples from the field of joint replacement surgery. Finally, we present opportunities for change at the health system, health service and clinician level, calling upon researchers, clinicians and policy makers to confront the surgical disparities experienced by Aboriginal and Torres Strait Islander people.

The association between socioeconomic status and joint replacement of the hip and knee: A population-based cohort study of older adults in Tasmania

BACKGROUND

A socioeconomic gradient exists in the utilisation of total hip replacements (THR) and total knee replacements (TKR) for osteoarthritis. However, the relations between socioeconomic status (SES) and time to THR or TKR is unknown.

AIM

To describe the association between SES and time to THR and TKR.

METHODS

1072 older-adults residing in Tasmania, Australia were studied. Incident primary THR and TKR were determined by data linkage to the Australian Orthopaedic Association National Joint Replacement Registry. At baseline, each participant's area-level SES was determined by the Index of Relative Socioeconomic Advantage and Disadvantage (IRSAD), from the Australian Bureau of Statistics' 2001 census data. IRSAD was analysed in two ways; 1) categorised into quartiles, whereby quartile 1 represented the most socioeconomically disadvantaged group, 2) the cohort dichotomised at the quartile 1 cut-point.

RESULTS

The mean age was 63.0 (±7.5) years, and 51% were women. Over the median follow-up of 12.9 (Interquartile range: 12.2-13.9) years, 56 (5%) participants had a THR, and 79 (7%) had a TKR. Compared to the most disadvantaged quartile, less disadvantaged participants were less likely to have a THR (i.e. less disadvantaged participants had a longer time to THR) (HR: 0.56, 95% CI 0.32, 1.00) but not TKR (HR: 0.90, 95% CI 0.53, 1.54). However, the former became non-significant after adjustment for pain and radiographic osteoarthritis, suggesting that the associations may be mediated by these factors.

CONCLUSIONS

This study suggests that time to joint replacement was determined according to the symptoms/need of the participants rather than their SES. This article is protected by copyright. All rights reserved.

Responsiveness, Reliability, and Validity of Arabic Version of Oxford Knee Score for Total Knee Arthroplasty

BACKGROUND

The Oxford Knee Score (OKS) is a reliable, valid, and sensitive assessment tool for individuals undergoing a total knee arthroplasty (TKA). The published psychometric assessment of the Arabic version of the OKS (OKS-Ar) is limited to male patients and has not been assessed for responsiveness following TKA. The aim of this study was to assess the reliability, validity, and responsiveness of the OKS-Ar in an inclusive population of patients undergoing TKA.

METHODS

One hundred Arabic-speaking patients awaiting TKA were assessed with the OKS-Ar, the Arabic version of the Knee injury and Osteoarthritis Outcome Score (KOOS-Ar), and a visual analogue scale for pain (VAS-P) in order to assess the correlation between the OKS-Ar and the KOOS-Ar and VAS-P and determine the construct validity. Repeat assessments were completed 7 to 10 days after the first assessment and 6 months after TKA.

RESULTS

Questionnaires were completed by 80 female and 20 male participants with a mean age of 62 ± 8 years. The test and retest median scores showed no significant difference from one another, with a strong Spearman correlation between the 2 measurements (rs = 0.94). Bland-Altman limits of agreement showed no significant bias. The Cronbach alpha was 0.85 indicating high internal consistency. There was no floor or ceiling effect before TKA, and the post-TKA ceiling effect was only 2%. The OKS-Ar pain component correlated strongly with the KOOS-Ar pain subscale (rs = 0.73). The OKS-Ar effect size was 3.09, which was larger than that of all of the KOOS subscales at 6 months after TKA.

CONCLUSIONS

To our knowledge, this is the first study to assess reliability, validity, and responsiveness of the OKS-Ar after TKA. The validity and reliability results are similar to those found for both the original English-language OKS and the OKS translated into other languages. We believe that this is also the first study to assess OKS-Ar responsiveness after TKA and to show a large effect size. We found that the OKS-Ar is a feasible, valid, reliable, and sensitive measurement tool to assess pain and function in TKA-treated individuals whose main language is Arabic.

Tackling the Burden of Osteoarthritis as a Health Care Opportunity in Indigenous Communities-A Call to Action

Osteoarthritis is a highly prevalent and disabling disease, causing a significant individual and socioeconomic burden worldwide. Until now, there has been a dearth of research exploring the impact of osteoarthritis in global Indigenous communities. Osteoarthritis has a similar risk factor profile to many chronic diseases that disproportionately affect Indigenous peoples. In this editorial, we argue that osteoarthritis and associated mobility restrictions play a central role in the chronic disease profile of Indigenous peoples. We present a call to action for clinicians and health care providers, researchers and policymakers to begin to recognise the interrelated nature of osteoarthritis and chronic disease. We have an opportunity to change the way we do business, to improve access to culturally secure osteoarthritis care and the health and wellbeing of Indigenous communities.

Comparison of individual and neighbourhood socioeconomic status in case mix adjustment of hospital performance in primary total hip replacement in Sweden: a register-based study

BACKGROUND

Case mix adjustment is a pre-requisite for valid measurement of healthcare performance and socioeconomic status (SES) is important to account for. Lack of information on individual-level SES has led to investigations into using a proxy for SES based on patient area of residence. The objective of this study was to use neighbourhood SES for case mix adjustment of performance indicators in total hip replacement (THR) in Sweden, and to compare with use of individual SES.

METHODS

Data from patient administrative systems and the Swedish Hip Arthroplasty Register were extracted for all patients undergoing THR in four Swedish regions. For each subject, individual data and neighbourhood data on country of birth, educational level, and income were provided by Statistics Sweden. Three variables were selected for analysis of performance; EQ-5D, hip pain and length of stay (LoS). In addition to socioeconomic information, several important clinical characteristics were used as case mix factors. Regression analysis was used to study each variable's impact on the three outcome variables and model fit was evaluated using mean squared error.

RESULTS

A total of 27,121 patients operated between 2010 and 2016 were included in the study. Both educational level and income were higher when based on neighbourhood information than individual information, while proportion born in Sweden was similar. Higher SES was generally found to be associated with better outcomes and lower LoS, albeit with certain differences between the different measures of SES. The predictive ability of the models was increased when adding information on SES to the clinical characteristics. The increase in predictive ability was higher for individual SES compared to neighbourhood SES. When analysing performance for the two providers with most diverging case mix in terms of SES, the inclusion of SES altered the relative performance using individual as well as neighbourhood SES.

CONCLUSIONS

Incorporating SES improves case mix adjustment marginally compared to using only clinical information. In this patient group, geographically derived SES was found to improve case mix adjustment compared to only clinical information but not to the same extent as actual individual-level SES.

Geographical and ethnic differences of osteoarthritis-associated hip and knee replacement surgeries in New Zealand: a population-based cross-sectional study

OBJECTIVES

To (1) explore the regional and ethnic differences in rates of publicly funded osteoarthritis-associated hip and knee replacement surgeries and (2) investigate the mortality after surgery.

DESIGN

Population-based, retrospective, cross-sectional study.

SETTING

General population in New Zealand.

PARTICIPANTS

Patients with osteoarthritis who underwent publicly funded primary hip and knee replacement surgeries in 2005-2017. Patients aged 14-99 years were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

Age-standardised rate, standardised mortality ratio (SMR) and 30 days, 90 days and 1 year mortality.

RESULTS

We identified 53 439 primary hip replacements and 50 072 primary knee replacements with a diagnosis of osteoarthritis. The number and age-standardised rates of hip and knee replacements increased over time. Māori had the highest age-standardised rate of hip replacements, followed by European/others and Pacific, and Asian had the lowest rate. Pacific had the highest age-standardised rate of knee replacements, followed by Māori and European/others, and Asian had the lowest rate. The Northern Health Network had the lowest rate of hip surgeries, and the Southern Health Network had the lowest rate of knee surgeries. The SMRs of patients undergoing hip and knee replacements were lower than the general population: 0.92 (95% CI 0.89 to 0.95) for hip and 0.79 (95% CI 0.76 to 0.82) for knee. The SMRs were decreasing over time. The patterns of 30 days, 90 days and 1 year mortality were similar to the SMR.

CONCLUSIONS

The numbers of publicly funded osteoarthritis-associated primary hip and knee replacements are steadily increasing. Māori people had the highest age-standardised rate of hip replacements and Pacific people had the highest rate of knee replacements. The Northern Health Network had the lowest rate of hip surgeries, and the Southern Health Network had the lowest rate of knee surgeries. Compared with the general population, patients who had hip and knee replacements have a better life expectancy.

Geographic variation and factors associated with rates of knee arthroplasty in Korea-a population based ecological study

Background

The recent increase in knee arthroplasty (KA) use in Korea is among the highest in the world. The rapid increase in KA use suggests that the KA use in Korea could have been affected by medically unjustifiable factors. This study aimed to examine the geographic variation in the rate of KA and its associated factors in Korea.

Methods

We used the data from the National Health Insurance in Korea in 2013, from which a total of 67,086 claims for KA were obtained. We calculated the age-sex-standardized KA rates of the entire population and the crude rates of the age groups 0–64 and 65 and over in 251 districts. We assessed the geographic variation of the KA rates and examined the associated factors with a multivariate linear regression with the KA rate as a dependent variable.

Results

The overall rate of KA in Korea was 132.7 per 100,000 persons. The rates of KA showed a four-fold variation. The deprivation index score and the number of beds in the small to medium sized hospitals showed a positive association with the rates of KA while the number of orthopedic surgeons showed a negative association.

Conclusions

Korea has been experiencing a rapid increase in the use of KA for the last decade or so, which was most prominent among the elderly population aged 65 and older. Our results suggest that the higher rate of KA is strongly related to a higher supply of beds and the socioeconomically deprived conditions. Considering that the decision concerning KA has room for discretion and also affects a considerable portion of health care expenditures, the use of KA should be thoroughly monitored with more emphasis on standardization in the decision making process and preventive measures that can lessen the need for KA.

Electronic supplementary material

The online version of this article (10.1186/s12891-019-2766-y) contains supplementary material, which is available to authorized users.

Unmet Needs of Aboriginal Australians With Musculoskeletal Pain: A Mixed-Method Systematic Review

OBJECTIVE

Musculoskeletal pain (MSP) conditions are the biggest cause of disability, and internationally, indigenous peoples experience a higher burden. There are conflicting reports about Aboriginal Australians and MSP. We conducted a systematic review to describe the prevalence, associated factors, impacts, care access, health care experiences, and factors associated with MSP among Aboriginal Australians.

METHODS

We used a systematic search of quantitative and qualitative scientific and grey literature (PROSPERO# CRD42016038342). Articles were appraised using the Mixed Methods Appraisal Tool. Due to study heterogeneity, a narrative synthesis was conducted.

RESULTS

Of 536 articles identified, 18 were included (14 quantitative, 4 qualitative), of high (n = 11), medium (n = 2), and low (n = 5) quality. Prevalence of MSP in Aboriginal populations was similar to or slightly higher than the non-Aboriginal population (prevalence rate ratio 1.1 for back pain, 1.2-1.5 for osteoarthritis [OA], and 1.0-2.0 for rheumatoid arthritis). Aboriginal people accessed primary care for knee or hip OA at approximately half the rate of non-Aboriginal people, and were less than half as likely to have knee or hip replacement surgery. Communication difficulties with health practitioners were the main reason why Aboriginal people with MSP choose not to access care. No articles reported interventions.

CONCLUSION

Findings provide preliminary evidence of an increased MSP burden among Aboriginal Australians, and particularly for OA, a mismatch between the disease burden and access to health care. To increase accessibility, health services should initially focus on improving Aboriginal patients' experiences of care, in particular by improving patient-practitioner communication. Implications for care and research are outlined.

Geographical variations in patient-reported outcomes after total hip arthroplasty between 2008 - 2012

BACKGROUND

Health care on equal terms is a cornerstone of the Swedish health care system. Total hip arthroplasty (THA) is considered a success story in Sweden with low frequency of reoperations and restored health-related quality of life (HRQoL). Administratively, health care in Sweden is locally self-governed by 21 counties. In this longitudinal nation-wide observational study we assessed the possible geographical variations in 1-year follow-up patient-reported outcomes (PROs): EQ-5D index, EQ VAS, Pain VAS and Satisfaction VAS.

METHODS

Study population consisted of 36,235 Swedish THA patients, operated during 2008 to 2012 due to hip osteoarthritis. Individual data came from Swedish Hip Arthroplasty Register, Statistics Sweden and National Board of Health and Welfare. We used descriptive statistics together with multivariable regression analysis to analyse the data.

RESULTS

We observed county level differences in both preoperative and postoperative PROs. The results showed that the differences observed in preoperative PROs could not fully explain the differences observed in postoperative PROs, even after adjustment for patient demographics (age, sex, BMI, Elixhauser comorbidity index, marital status, educational level and disposable income). This indicates that other factors might influence the outcome after THA.

CONCLUSION

Likely, structural and process differences such as indication for surgery have an influence on PROs after surgery. Standardization of care at hospital levels may decrease geographical variations in postoperative HRQoL. Remaining differences will then possibly be associated to patient demographics.

Characterization of indigenous community engagement in arthritis studies conducted in Canada, United States of America, Australia and New Zealand

BACKGROUND

Research adhering to community engagement processes leads to improved outcomes. The level of Indigenous communities' engagement in rheumatology research is unknown.

OBJECTIVE

To characterize the frequency and level of community engagement reporting in arthritis studies conducted in Australia (AUS), Canada (CAN), New Zealand (NZ) and the United States of America (USA).

METHODS

Studies identified through systematic reviews on topics of arthritis epidemiology, disease phenotypes and outcomes, health service utilization and mortality in Indigenous populations of AUS, CAN, NZ and USA, were evaluated for their descriptions of community engagement. The level of community engagement during inception, data collection and results interpretation/dissemination stages of research was evaluated using a custom-made instrument, which ranked studies along the community engagement spectrum (i.e. inform-consult-involve-collaborate-empower). Meaningful community engagement was defined as involving, collaborating or empowering communities. Descriptive analyses for community engagement were performed and secondary non-parametric inferential analyses were conducted to evaluate the possible associations between year of publication, origin of the research idea, publication type and region of study; and meaningful community engagement.

RESULTS

Only 34% (n = 69) of the 205 studies identified reported community engagement at ≥ 1 stage of research. Nearly all studies that engaged communities (99% (n = 68)) did so during data collection, while only 10% (n = 7) did so at the inception of research and 16% (n = 11) described community engagement at the results' interpretation/dissemination stage. Most studies provided community engagement descriptions that were assessed to be at the lower end of the spectrum. At the inception of research stage, 3 studies reported consulting communities, while 42 studies reported community consultation at data collection stage and 4 studies reported informing or consulting communities at the interpretation/dissemination of results stage. Only 4 studies described meaningful community engagement through all stages of the research. Inferential statistics identified that studies with research ideas that originated from the Indigenous communities involved were significantly more associated with achieving meaningful community engagement.

CONCLUSIONS

The reporting of Indigenous community engagement in published arthritis studies is limited in frequency and is most frequently described at the lower end of the community engagement spectrum. Processes that support meaningful community engagement are to be promoted.

Body Mass Index Is Associated With All-cause Mortality After THA and TKA

BACKGROUND

Both obesity and underweight are associated with a higher risk of mortality in adulthood, but the association between mortality after arthroplasty and extreme ranges of body mass index (BMI) have not been evaluated beyond the first year.

QUESTIONS/PURPOSES

The purpose of this study was to investigate the association between BMI and all-cause mortality after TKA and THA.

METHODS

Data from two arthroplasty registries, the St Vincent's Melbourne Arthroplasty (SMART) Registry from Australia and the Kaiser Permanente Total Joint Replacement Registry (KPTJRR) from the United States, were used to identify patients aged ≥ 18 years undergoing elective TKAs and THAs between January 1, 2002, and December 31, 2013. Same-day bilateral THA and hemiarthroplasties were excluded. All-cause mortality was recorded from the day of surgery to the end of the study (December 31, 2013). Data capture was complete for the SMART Registry. No patients were lost to followup in the KPTJRR cohort and 2959 (5%) THAs and 5251 (5%) TKAs had missing data. Cox proportional hazard regression was used to estimate the all-cause mortality associated with six BMI categories: underweight (< 18.5 kg/m), normal weight (18.5-24.9 kg/m), overweight (25.0-29.9 kg/m), obese class I (30.0-34.9 kg/m), obese class II (35.0-39.9 kg/m), and obese class III (> 40 kg/m). For TKA, the SMART cohort had a median followup of 5 years (range, 0-12 years) and the KPTJRR cohort had a median followup of 4 years (range, 0-12 years). For THA, the SMART cohort had a median followup of 5 years (range, 0-12 years) and the KPTJRR cohort had a median followup of 4 years (range, 0-12 years).

RESULTS

In both the Australian and US cohorts, being underweight (Australia: hazard ratio [HR], 3.72; 95% confidence interval [CI], 1.94-7.08; p < 0.001 and United States: HR, 1.88; 95% CI, 1.33-2.64; p < 0.001) was associated with higher all-cause mortality after TKA, whereas obese class I (Australia: HR, 0.66; 95% CI, 0.47-0.92; p = 0.015; United States: HR, 0.71; 95% CI, 0.66-0.78; p < 0.001) or obese class II (Australia: HR, 0.54; 95% CI, 0.35-0.82; p = 0.004; United States: HR, 0.73; 95% CI, 0.66-0.81; p < 0.001) was associated with lower mortality when compared with normal-weight patients. In the US cohort, being overweight was also associated with a lower risk of mortality (HR, 0.76; 95% CI, 0.71-0.82; p < 0.001). In the US cohort, being underweight had a higher risk of mortality after THA (HR, 2.09; 95% CI, 1.65-2.64; p < 0.001), whereas those overweight (HR, 0.73; 95% CI, 0.67-0.80; p < 0.001), obese class I (HR, 0.68; 95% CI, 0.62-0.75; p < 0.001), or obese class II (HR, 0.71; 95% CI, 0.62-0.81; p < 0.001) were at a lower risk of mortality after THA when compared with normal-weight patients. In patients undergoing THA in the Australian cohort, we observed no association between BMI and risk of death.

CONCLUSIONS

We found that even severe obesity is not associated with a higher risk of death after arthroplasty. Patients should be informed of this when considering surgery. Clinicians should be cautious when considering total joint arthroplasty in underweight patients without first considering their nutritional status.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Differences in presentation, progression and rates of arthroplasty between hip and knee osteoarthritis: Observations from an osteoarthritis cohort study-a clear role for conservative management

Aim

To describe the natural progression and the rates of arthroplasty of a cohort of hip and knee osteoarthritis (OA) patients.

Methods

An observational study of 247 consecutive patients who attended an OA clinic between May 2008 and August 2009. Follow‐up survey was conducted from July 2014 to December 2014, with the primary end point being joint replacement surgery.

Results

One hundred and sixty‐seven patients had knee OA and 80 patients had hip OA. When adjusted for other variables (age, gender, body mass index, Kellgren‐Lawrence stage, symptom duration, presence of OA elsewhere and pain score), patients with hip OA demonstrated 86% increased hazard of surgery compared to knee OA patients (95% CI increase of 19% to 193%). At 6 years after initial consultation, 67% of patients with knee OA did not require a knee replacement surgery, while 40% (30, 51) of hip OA patients did not undergo surgery (95% CI: 59–74%). Overall at 6 years, 58% of patients (95% CI: 51–64%) did not undergo joint replacement surgery.

Conclusion

Knee and hip OA patients appear to behave differently, with hip OA patients more likely to undergo arthroplasty. There is a significant number of both hip OA and knee OA patients who did not require arthroplasty at the end of 6 years, suggesting a major role for conservative therapy.

Rates of hip and knee joint replacement amongst different ethnic groups in England: an analysis of National Joint Registry data

OBJECTIVE

Despite a health care system that is free at the point of delivery, ethnic minorities may not always get care equitable to that of White patients in England. We examined whether ethnic differences exist in joint replacement rates and surgical practice in England.

DESIGN

373,613 hip and 428,936 knee National Joint Registry (NJR) primary replacement patients had coded ethnicity in Hospital Episode Statistics (HES). Age and gender adjusted observed/expected ratios of hip and knee replacements amongst ethnic groups were compared using indirect standardisation. Associations between ethnic group and type of procedure were explored and effects of demographic, clinical and hospital-related factors examined using multivariable logistic regression.

RESULTS

Adjusted standardised observed/expected ratios were substantially lower in Blacks and Asians than Whites for hip replacement (Blacks 0.33 [95% CI, 0.31-0.35], Asians 0.20 [CI, 0.19-0.21]) and knee replacement (Blacks 0.64 [CI, 0.61-0.67], Asians 0.86 % [CI, 0.84-0.88]). Blacks were more likely to receive uncemented hip replacements (Blacks 52%, Whites 37%, Asians 44%; P < 0.001). Black men and women aged <70 years were less likely to receive unicondylar or patellofemoral knee replacements than Whites (men 10% vs 15%, P = 0.001; women 6% vs 14%, P < 0.001). After adjustment for demographic, clinical and hospital-related factors, Blacks were more likely to receive uncemented hip replacement (OR 1.43 [CI, 1.11-1.84]).

CONCLUSIONS

In England, hip and knee replacement rates and prosthesis type given differ amongst ethnic groups. Whether these reflect differences in clinical need or differential access to treatment requires urgent investigation.

Healthcare utilization for arthritis by indigenous populations of Australia, Canada, New Zealand, and the United States: A systematic review☆

PURPOSE

Indigenous populations of Australia, Canada, New Zealand, and the United States of America (USA) experience a higher prevalence of arthritis conditions. Differences in clinical outcomes and mortality may reflect healthcare service use inequities. The objective of this study was to summarize healthcare service use patterns described in the existing literature in order to identify gaps and inform strategies to limit the pronounced negative impact of arthritis on Indigenous populations.

METHODS

Medline, EMBASE, CINAHL, and Indigenous-specific electronic databases (to June 2015) were used to identify cohort, case-control and cross-sectional studies describing healthcare service use by Indigenous populations with specified inflammatory arthritis, osteoarthritis, or rheumatic disease conditions. We extracted information on the study setting and methodology, primary outcome and assessed study quality, and risk of bias.

RESULTS

In total, 19 studies were identified describing three types of healthcare service use: physician visits, hospitalizations, and surgeries. In Canada and New Zealand, Indigenous populations had 36-51% fewer visits to specialists than the non-Indigenous population. Indigenous populations in Canada, New Zealand, and the USA had 37-300% more hospitalizations due to arthritis complications than the non-Indigenous population. Indigenous populations in Australia, Canada, and New Zealand had 27-85% fewer arthroplasties for osteoarthritis than the non-Indigenous population.

CONCLUSIONS

Indigenous populations had higher hospitalization rates but lower use of specialized services for arthritis conditions. Strategies to improve access to specialized arthritis services might reduce health outcome inequities.

Few geographic and socioeconomic variations exist in primary total shoulder arthroplasty: a multi-level study of Australian registry data

Background

Associations between socioeconomic position (SEP) and the uptake of primary total shoulder arthroplasty (TSA) is not well understood in the Australian population, thus potentially limiting equitable allocation of healthcare resources. We used the Australian Orthopaedic Association National Joint Replacement Registry (AOA NJRR) to examine whether geographic or socioeconomic variations exist in TSA performed for a diagnosis of osteoarthritis 2007–11 for all Australians aged ≥40 years.

Methods

Primary anatomical and reverse TSA data were extracted from the AOA NJRR which captures >99 % of all TSA nationally. Residential addresses were cross-referenced to Australian Bureau of Statistics 2011 Census data to identify SEP measured at the area-level (categorised into deciles), and geographic location defined as Australian State/Territory of residence. We used a Poisson distribution for the number of TSA over the study period, and modelled the effects of age, SEP and geographic location using multilevel modelling.

Results

During 2007–11, we observed 6,123 TSA (62.2 % female). For both sexes, TSA showed a proportional increase with advancing age. TSA did not vary by SEP or geographic location, with the exception of greater TSA among men in New South Wales.

Conclusions

Using a national registry approach we provide the first reliable picture of TSA at a national level. The uptake of TSA was equitable across SEP; however, there was some variation between the States/Territories. With an aging population, it is imperative that monitoring of major surgical procedures continues, and be focused toward determining whether TSA uptake correlates with need across different social and area-based groups.

Personal Perspectives on Enablers and Barriers to Accessing Care for Hip and Knee Osteoarthritis

BACKGROUND

Despite increasing demand for joint replacement surgery and other health services for hip and knee osteoarthritis (OA), barriers and enablers to individual access to care are not well understood. A comprehensive understanding of drivers at all levels is needed to inform efforts for improving access.

OBJECTIVE

The aim of this study was to explore perceived barriers and enablers to receiving conservative (nonsurgical) and surgical treatment for hip and knee OA.

DESIGN

This was a qualitative study using directed content analysis.

METHODS

Semistructured telephone interviews were conducted, with 33 participants randomly sampled from an Australian population-based survey of hip and knee OA. Each interview covered factors contributing to receiving treatment for OA and perceived barriers to accessing care. Interview transcripts were coded and organized into themes.

RESULTS

Key barriers to accessing care for OA included medical opinions about saving surgery for later and the appropriate age for joint replacement. Other common barriers included difficulty obtaining referrals or appointments, long waiting times, work-related issues, and limited availability of primary and specialist care in some areas. Several participants perceived a lack of effective treatment for OA. Private health insurance was the most frequently cited enabler and was perceived to support the costs of surgical and conservative treatments, including physical therapy, while facilitating faster access to surgery. Close proximity to services and assistance from medical professionals in arranging care also were considered enablers.

CONCLUSIONS

People with hip or knee OA experience substantial challenges in accessing treatment, and these challenges relate predominantly to health professionals, health systems, and financial factors. Private health insurance was the strongest perceived enabler to accessing care for OA.

Latent Class Growth Analysis predicts long term pain and function trajectories in total knee arthroplasty: a study of 689 patients

OBJECTIVE

To characterize groups of subjects according to their trajectory of knee pain and function over 1 to 5 years post total knee arthroplasty (TKA).

METHODS

Patients from one centre who underwent primary TKA (N = 689) between 2006 and 2008. The Knee Society Score (KSS) was collected pre-operatively and annually post-operatively. Latent Class Growth Analysis (LCGA) was used to classify groups of subjects according to their trajectory of knee pain and function over 1-5 years post-surgery.

RESULTS

LCGA identified a class of patients with persistent moderate knee pain (22.0%). Predictors (OR, 95% CI) of moderate pain trajectory class membership were pre-surgery SF12 mental component summary (MCS) per 10 points (0.65, 0.54-0.79) and physical component summary (PCS) per 10 points (0.50, 0.33-0.76), Charlson Comorbidity Index (CCI) one (1.70, 1.07-2.69) and ≥two (2.82, 1.59-4.81) and the absence of computer-navigation (2.26, 1.09-4.68). LCGA also identified a class of patients with poor function (23.0%). Predictors of low function trajectory class membership were, female sex (3.31, 1.95-5.63), advancing age per 10 years (2.27, 1.69-3.02), pre-surgery PCS per 10 points (0.50, 0.33-0.74), obesity (1.69, 1.05-2.72), morbid obesity (3.12, 1.55-6.27) and CCI ≥two (2.50, 1.41-4.42).

CONCLUSIONS

Modifiable predictors of poor response to TKA included baseline co-morbidity, physical and mental well-being and obesity. This provides useful information for clinicians in terms of informing patients of the expected course of longer term outcomes of TKA and for developing prediction algorithms that identify patients in whom there is a high likelihood of poor surgical response.

Direct hospital cost determinants following hip and knee arthroplasty

OBJECTIVE

Total joint arthroplasty (TJA) places a significant economic burden on health care resources. This cohort study examines the costs associated with arthroplasty in 827 patients undergoing hip and knee TJA from January 2011 to June 2012 at a single center in Melbourne, Australia.

METHODS

Data included total inpatient, outpatient, and readmissions costs in the 30 days following TJA. Factors associated with cost were modeled using negative binomial regression and extrapolated to the Australian population.

RESULTS

The base cost (i.e., the cost for a patient with no modifying factors) over the first 30 days following TJA was $13,060 Australian (AU) (interquartile range $12,126-14,067 AU). The median length of stay was 4 days (range 2-33 days) and 35 patients (4%) were readmitted in the first 30 days following index TJA, the majority of whom had a surgical site infection (SSI) (74%). The following factors were independently associated with increased costs: SSI, preoperative warfarin therapy, American Society of Anesthesiologists score of 3 or 4, hip TJA, increasing operation time, increasing postoperative blood transfusion requirements, other nosocomial infections, postoperative venous thromboembolism (VTE), pressure ulcers, postoperative confusion, and acute urinary retention. Based on data from the present study, the cost of TJA in Australia is estimated to exceed $1 billion AU per year. Preventable postoperative complications were major cost drivers: SSI and VTE added a further $97 million AU and $66 million AU, respectively, to arthroplasty costs in the first 30 days following surgery.

CONCLUSION

This unique study has identified important factors influencing TJA costs and providing guidance for future research and resource allocation.

Massachusetts health reform and disparities in joint replacement use: difference in differences study

OBJECTIVE

To estimate the impact of the insurance expansion in 2006 on use of knee and hip replacement procedures by race/ethnicity, area income, and the use of hospitals that predominantly serve poor people ("safety net hospitals").

DESIGN

Quasi-experimental difference in differences study examining change after reform in the share of procedures performed in safety net hospitals by race/ethnicity and area income, with adjustment for patients' residence, demographics, and comorbidity.

SETTING

State of Massachusetts, United States.

PARTICIPANTS

Massachusetts residents aged 40-64 as the target beneficiaries of reform and similarly aged residents of New Jersey, New York, and Pennsylvania as the comparison (control) population.

MAIN OUTCOMES MEASURES

Number of knee and hip replacement procedures per 10 000 population and use of safety net hospitals. Procedure counts from state discharge data for 2.5 years before and after reform, and multivariate difference in differences. Poisson regression was used to adjust for demographics, economic conditions, secular time, and geographic factors to estimate the change in procedure rate associated with health reform by race/ethnicity and area income.

RESULTS

Before reform, the number of procedures (/10 000) in Massachusetts was lower among Hispanic people (12.9, P<0.001) than black people (28.1) and white people (30.1). Overall, procedure use increased 22.4% during the 2.5 years after insurance expansion; reform in Massachusetts was associated with a 4.7% increase. The increase associated with reform was significantly higher among Hispanic people (37.9%, P<0.001) and black people (11.4%, P<0.05) than among white people (2.8%). Lower income was not associated with larger increases in procedure use. The share of knee and hip replacement procedures performed in safety net hospitals in Massachusetts decreased by 1.0% from a level of 12.7% before reform. The reduction was larger among Hispanic people (-6.4%, P<0.001) than white people (-1.0%), and among low income residents (-3.9%, p<0.001) than high income residents (0%).

CONCLUSIONS

Insurance expansion can help reduce disparities by race/ethnicity but not by income in access to elective surgical care and could shift some elective surgical care away from safety net hospitals.

Propensity score matching and randomization

OBJECTIVES

We used elective total joint replacement (TJR) as a case study to demonstrate selection bias toward offering this procedure to younger and healthier patients.

STUDY DESIGN AND SETTING

Longitudinal data from 2,202 men were integrated with hospital data and mortality records. Study participants were followed from recruitment (1996-1999) until TJR, death, or 2007 (end of follow-up). A propensity score (PS) was constructed to quantify each subject's likelihood of undergoing TJR. TJR recipients were later matched to their non-TJR counterparts by PS and year of hospitalization. Ten-year mortality from index admission was compared between cases and controls.

RESULTS

Overall, 819 (37.2%) had TJR. Those were younger, healthier, and belonged to higher socioeconomic classes compared with those who were not proposed for surgery. Of the TJR recipients, 718 were matched to 1,109 controls. Cases and controls had similar characteristics and similar years of follow-up from recruitment till index admission. Nonetheless, controls were more likely to die (39.5%) compared with 14.5% in TJR cases (P < 0.001).

CONCLUSION

Selection for elective procedures may introduce bias in prognostic features not accounted for by PS matching. Caution must be exercised when long-term outcomes are compared between surgical and nonsurgical groups in a population at risk for that surgical procedure.

Regional variability in the rates of total hip replacement in Spain

The role of economic resources, distribution of providers, and demography may explain part of the variability found in hip arthroplasty in international surveys. We aimed to investigate the influence of ageing index, health budget, and density of orthopaedic surgeons in the regional variability of the primary and revision THR rate in Spain, where regions decide on the allocation of their health budget.Inpatient database of hip procedures for years 1997 to 2011 was obtained from the Spanish Ministry of Health, segregated for each of the 17 regional health services in Spain. Crude and adjusted rates (direct method with total Spanish population per year) were calculated and used as dependent variables. Ageing index, Health Expenditure of Gross Domestic Product (GDP), and number of orthopaedic surgeons per region were used as independent variables. Negative binomial regression analysis model and Poisson regression were calculated to estimate the risk contribution of the ecological variables.A total of 425,914 hip procedures, with 367,489 primary (mean crude rate = 124 × 105 inhabitants/year) and 58,425 revision hips (21 × 105 inhabitants/year) were included in the analysis. Regional variability was higher than expected in THR in Spain, despite a universal coverage health system in which equity may be challenged in the administration of hip arthroplasty. This was found particularly for primary THR. When hip replacement rates were adjusted for sex and age, the regional ageing index, the density of orthopaedic surgeons and the regional health budget could only partially explain risk ratio changes.

Imbalance of Prevalence and Specialty Care for Osteoarthritis for First Nations People in Alberta, Canada

Objective.

To estimate the population-based prevalence and healthcare use for osteoarthritis (OA) by First Nations (FN) and non-First Nations (non-FN) in Alberta, Canada.

Methods.

A cohort of adults with OA (≥ 2 physician claims in 2 yrs or 1 hospitalization with ICD-9-Clinical Modification code 715x or ICD-10-Canadian Adaptation code M15-19, 1993–2010) was defined with FN determination by premium payer status. Prevalence rates (2007/8) were estimated from the cohort and the population registered with the Alberta Health Care Insurance Plan. Rates of outpatient primary care and specialist visits (orthopedics, rheumatology, internal medicine), arthroplasty (hip and knee), and all-cause hospitalization were estimated.

Results.

OA prevalence in FN was twice that of the non-FN population [16.1 vs 7.8 cases/100 population, standardized rate ratio (SRR) adjusted for age and sex 2.06, 95% CI 2.00–2.12]. The SRR (adjusted for age, sex, and location of residence) for primary care visits for OA was nearly double in FN compared with non-FN (SRR 1.88, 95% CI 1.87–1.89), and internal medicine visits were increased (SRR 1.25, 95% CI 1.25–1.26). Visit rates with an orthopedic surgeon (SRR 0.49, 95% CI 0.48–0.50) or rheumatologist (SRR 0.62, 95% CI 0.62–0.63) were substantially lower in FN with OA. Hip and knee arthroplasties were performed less frequently in FN with OA (SRR 0.48, 95% CI 0.47–0.49), but all-cause hospitalization rates were higher (SRR 1.59, 95% CI 1.58–1.60).

Conclusion.

We estimate a 2-fold higher prevalence of OA in the FN population with differential healthcare use. Reasons for higher use of primary care and lower use of specialty services and arthroplasty compared with the general population are not yet understood.

Associations between socioeconomic status and primary total knee joint replacements performed for osteoarthritis across Australia 2003-10: data from the Australian Orthopaedic Association National Joint Replacement Registry

Background

Relatively little is known about the social distribution of total knee joint replacement (TKR) uptake in Australia. We examine associations between socioeconomic status (SES) and TKR performed for diagnosed osteoarthritis 2003–10 for all Australian males and females aged ≥30 yr.

Methods

Data of primary TKR (n = 213,018, 57.4% female) were ascertained from a comprehensive national joint replacement registry. Residential addresses were matched to Australian Census data to identify area-level social disadvantage, and categorised into deciles. Estimated TKR rates were calculated. Poisson regression was used to model the relative risk (RR) of age-adjusted TKR per 1,000py, stratified by sex and SES.

Results

A negative relationship was observed between TKR rates and SES deciles. Females had a greater rate of TKR than males. Surgery utilisation was greatest for all adults aged 70-79 yr. In that age group differences in estimated TKR per 1,000py between deciles were greater for 2010 than 2003 (females: 2010 RR 4.32 and 2003 RR 3.67; males: 2010 RR 2.04 and 2003 RR 1.78).

Conclusions

Identifying factors associated with TKR utilisation and SES may enhance resource planning and promote surgery utilisation for end-stage osteoarthritis.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2474-15-356) contains supplementary material, which is available to authorized users.

The pathway to orthopaedic surgery: a population study of the role of access to primary care and availability of orthopaedic services in Ontario, Canada

OBJECTIVE

To examine the impact of access to primary care physicians (PCPs), geographic availability of orthopaedic surgeons, socioeconomic status (SES), proportion of older population (≥65 years) and proportion of rural population on orthopaedic surgeon office visits and orthopaedic surgery.

DESIGN

Population multilevel study.

SETTING

Ontario, Canada.

PARTICIPANTS

Ontario residents 18 years or older who had visits to orthopaedic surgeons or an orthopaedic surgery for musculoskeletal disorders in 2007/2008.

PRIMARY AND SECONDARY OUTCOMES

Office visits to orthopaedic surgeons and orthopaedic surgery.

RESULTS

Access to PCPs and the index of geographic availability of orthopaedic surgeons, but not SES, were significantly associated with orthopaedic surgeon office visits. There was a significant interaction between access to PCPs and orthopaedic surgeon geographic availability for the rate of office visits, with access to PCPs being more important in areas of low geographic availability of orthopaedic surgeons. After controlling for office visits with orthopaedic surgeons, the index of geographic availability of orthopaedic surgeons was no longer significantly associated with orthopaedic surgery.

CONCLUSIONS

The findings suggest that, particularly, in areas with low access to PCPs or with fewer available orthopaedic surgeons, residents are less likely to have orthopaedic surgeon office visits and in turn are less likely to receive surgery. Efforts to address adequate access to orthopaedic surgery should also include improving and facilitating access to PCPs for referral, particularly in geographic areas with low orthopaedic surgeon availability.

Electronic health databases for epidemiological research on joint replacements: considerations when making cross-national comparisons

PURPOSE

The purpose of this study was to examine the rate of primary knee, hip, or shoulder replacement among persons with osteoarthritis (OA) of the knee by gender and age comparing two nations in similar periods using electronic health records, but with different health-care systems.

METHODS

Two electronic health care databases of anonymized information were used to construct cohorts of adults with OA of the knee from the United Kingdom (UK) and the United States. Patients were required to have activity in the database at least 6 months before the first diagnosis of knee OA ("index diagnosis") in the study period to ensure that the patient samples were eligible for medical evaluation. The outcomes (numerator) measured were primary knee, hip, or shoulder replacement or the composite of primary knee, hip, or shoulder replacement. The denominator was the person-time at risk computed from time from the date of the index diagnosis to the date of each outcome separately or to the end of the database period if no outcome was documented.

RESULTS

There were 93,146 subjects in the UK and 1,468,217 in the United States who were aged 18+ years and met the study eligibility criteria. The composite joint replacement rate (hip, knee, or shoulder) ranged from 11.89 per 100 person-years (PY) in the Unites States to 4.13 per 100 PY in the UK Primary knee replacements rates ranged from 10.38 per 100 PY in the Unites States to 3.40 per 100 PY in the UK and occurred at a somewhat higher rate in males than females in both countries. Both primary hip and shoulder replacement rates were higher in the Unites States than in the UK (hip: 1.19 per 100 PY and 0.76 per 100 PY; shoulder: 0.19 per 100 PY and 0.03 per 100 PY, respectively). The median time to a primary hip or knee replacement in the UK was approximately twice as long as in the Unites States.

CONCLUSIONS

Knee replacements are not an uncommon event in persons with knee OA occurring throughout the adult life span, with the rate steeply rising in both sexes until aged 75 years. Although the pattern of the age-specific joint replacement rates was similar between sexes, the magnitude of the rates was markedly lower in the UK.

Education attainment is associated with patient-reported outcomes: findings from the Swedish Hip Arthroplasty Register

BACKGROUND

Age, sex, and medical comorbidities may be associated with differences in patient-reported outcome scores after THA. Highest level of education may be a surrogate for socioeconomic status, but the degree to which this is associated with patient-reported outcomes after THA is not known.

QUESTIONS/PURPOSES

We investigated the national Swedish Hip Arthroplasty Register for the association of education attainment on patient-reported outcomes 1 year after THA; specifically, we evaluated level of education attainment against health-related quality of life (HRQoL), pain reduction, and satisfaction with treatment 1 year after THA.

METHODS

All THAs for osteoarthritis performed from 2005 through 2007 with complete patient-reported outcome measures (representing 49% of the THAs performed for this diagnosis) were selected from the Swedish Hip Arthroplasty Register. These cases were merged with national databases containing education attainment, marital status, and comorbidities (n = 11,464; mean age of patients, 64 years). The patient-reported outcome measure protocol included the HRQoL measure EuroQol five-dimension scale (EQ-5D), a VAS for pain, the Charnley classification survey, and a VAS addressing THA satisfaction. Linear regression analyses determined the association of preoperative patient factors with patient-reported outcomes.

RESULTS

High education attainment was associated with higher HRQoL (EQ-5D index ß(high) = 0.03 ± 0.01; EQ VAS ß(high) = 2.6 ± 0.5) after THA, whereas those with low and medium education were at risk for lower HRQoL. High education was associated with less pain after treatment (ß(high) = -3.3 ± 0.05). Individuals with low or medium education were at risk for less satisfaction with THA (p < 0.001).

CONCLUSIONS

Our results suggest clinicians should support patients with low and medium education to a greater extent. Identification of patients who will benefit most from THA and educating those at risk for poorer outcomes, like patients with low and medium education, ultimately may improve patient satisfaction, HRQoL, pain, and the cost utility of THA.

LEVEL OF EVIDENCE

Level III, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Factors influencing regional variability in the rate of total knee arthroplasty

BACKGROUND AND PURPOSE

Geographic variations in knee arthroplasty have been detected through international surveys. We aim to investigate in this study the influence of aging index, health budget, and number of orthopedic surgeons in the regional variations of the primary and revision TKA rate in a single European country, Spain.

MATERIAL AND METHODS

Inpatient database of knee arthroplasty procedures for years 1997 to 2010 was obtained from the Spanish Ministry of Health, including 393,714 primaries and 37,037 revisions, segregated for each of the 17 regional health services in Spain. Crude and adjusted rates (direct method with total Spanish population per year) were calculated and used as dependent variables. Aging index, regional health budget, and number of orthopedic surgeons per region were used as independent variables in a Kruskal-Wallis test and a negative binomial regression analysis model.

RESULTS AND CONCLUSIONS

With a mean crude rate for Spain of 76 primary TKA and 7 revision surgeries per 10(5) population and year, the mean adjusted rate per region oscillated between 702 and 27 primary TKA and 87 and 3 revisions per 10(5). A model was adjusted confirming the influence of aging index, health budget, and number of surgeons, but regional variations remained partly unexplained by these factors.

Associations of educational attainment, occupation, and community poverty with hip osteoarthritis

OBJECTIVE

To examine cross-sectional baseline data from the Johnston County Osteoarthritis Project for the association between individual and community socioeconomic status (SES) measures with hip osteoarthritis (OA) outcomes.

METHODS

We analyzed data on 3,087 individuals (68% white and 32% African American). Educational attainment and occupation were used as individual measures of SES. Census block group household poverty rate was used as a measure of community SES. Hip OA outcomes included radiographic OA and symptomatic OA in one or both hip joints. Multivariable logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the association of each hip OA outcome with each SES variable separately, and then with all SES measures simultaneously. Associations between hip OA outcomes and SES variables were evaluated for effect modification by race and sex.

RESULTS

Living in a community of high household poverty rate showed independent associations with hip radiographic OA in one or both hips (OR 1.50, 95% CI 1.18-1.92) and bilateral (both hips) radiographic OA (OR 1.87, 95% CI 1.32-2.66). Similar independent associations were found between low educational attainment among those with symptomatic OA in one or both hips (OR 1.44, 95% CI 1.09-1.91) or bilateral symptomatic OA (OR 1.91, 95% CI 1.08-3.39), after adjusting for all SES measures simultaneously. No significant associations were observed between occupation and hip OA outcomes, nor did race or sex modify the associations.

CONCLUSION

Our data provide evidence that hip OA outcomes are associated with both education and community SES measures, associations that remained after adjustment for covariates and all SES measures.

Primary osteoarthritis of the hip: a genetic disease caused by European genetic variants

Primary osteoarthritis of the hip is a separate phenotype that occurs at a rate of 3% to 6% in the populations of the world with European ancestry. In all non-European populations, there is a consistent rarity of primary osteoarthritis that suggests a different etiology for these few patients. Family, sibling, and twin studies prove primary osteoarthritis to be a genetic disease with a 50% heritability caused by European genetic variants. The genetic basis is reinforced by the lower rate of primary osteoarthritis in American minorities consistent with their degree of European gene admixture. Whether the mechanism of degeneration of primary osteoarthritis may be secondary through a morphologic deformity, such as femoroacetabular impingement, remains unknown. The virtual absence of the disease in non-Europeans indicates that the European gene component is necessary for the expression of this separate phenotype of osteoarthritis.

Trends and geographical variation of primary hip and knee joint replacement in Germany

OBJECTIVE

Considerable variation in total hip replacement and total knee replacement (THR/TKR) between regions has been described. The aim of this study was to explore geographical variation in THR and TKR in Germany and to analyse potentially explanatory variables.

METHOD

We used data of Germany's largest statutory health insurer. Between 2005 and 2009 451,108 THR and 335,022 TKR were performed. Age-standardised joint replacement rates were calculated for 16 federal states and 407 counties. We performed cluster (Moran's I) and spatial error regression analyses including regional deprivation, osteoarthritis rate, urbanity and number of orthopaedic specialists as dependent variables on county level.

RESULTS

In 2009 the overall age-standardised and crude rates were 148.9 (95% CI (confidence interval) 147.6-151.1) and 290.2 for THR, and 132.5 (95% CI 131.3-133.6) and 232.7 for TKR. Between counties THR rates differed by factor 2 (106.1-215.8) and showed significant clusters with high utilisation in South and Northwest Germany. TKR rates differed by factor 3.2 (69.1-219.5) and were also high in South Germany whereas almost all areas in East Germany showed low replacement rates. Differences were pronounced when restricting the analysis to cases with an indication of osteoarthritis. All tested predictors could be identified as significant explanatory variables (each P < 0.001).

CONCLUSION

This study proofed considerable and consistent geographic variation of THR and TKR in Germany. Thereby relevant explanatory factors were identified. These results may foster the discussion and future research in health services which should include areas of patients' and doctors' expectation, financial aspects and an outcome-based definition of appropriate supply.

Utilisation of primary total knee joint replacements across socioeconomic status in the Barwon Statistical Division, Australia, 2006-2007: a cross-sectional study

OBJECTIVES

There are few Australian data that examine the association between total knee joint replacement (TKR) utilisation and socioeconomic status (SES). This study examined TKR surgeries with a diagnosis of osteoarthritis (OA) performed for residents of Barwon Statistical Division (BSD) for 2006-2007.

DESIGN

Cross-sectional.

SETTING

BSD, South-eastern Victoria, Australia

PARTICIPANTS

All patients who underwent a TKR for OA, 2006-2007, and whose residential postcode was identified as within the BSD of Australia, and for whom SES data were available, were eligible for inclusion.

PRIMARY OUTCOME MEASURE

Primary TKR data ascertained from the Australian Orthopaedic Association National Joint Replacement Registry. Residential addresses were matched with the Australian Bureau of Statistics census data, and the Index of Relative Socioeconomic Disadvantage was used to determine SES, categorised into quintiles whereby quintile 1 indicated the most disadvantaged and quintile 5 the least disadvantaged. Age-specific and sex-specific rates of TKR utilisation per 1000 person-years were reported for 10-year age bands.

RESULTS

Females accounted for 62.7% of the 691 primary TKR surgeries performed during 2006-2007. The greatest utilisation rates of TKR in males was 7.6 observed in those aged >79 years, and in 10.2 in females observed in those aged 70-79 years. An increase in TKR was observed for males in SES quintile four compared to quintile 1 in which the lowest utilisation which was observed (p=0.04). No differences were observed in females across SES quintiles.

CONCLUSIONS

Further investigation is warranted on a larger scale to examine the role that SES may play in TKR utilisation, and to determine whether any social disparities in TKR utilisation reflect health system biases or geographic differences.

Social determinants and osteoarthritis outcomes

Osteoarthritis (OA) is one of the most frequently occurring musculoskeletal diseases, posing a significant public health problem due to its impact on pain and disability. Traditional risk factors fail to account for all of the risk observed for OA outcomes. In recent years, our view of disease causation has broadened to include health risks that are created by an individual's socioeconomic circumstances. Early research into social determinants has focused on social position and explored factors related to the individual such as education, income and occupation. Results from these investigations suggest that low education attainment and nonprofessional occupation are associated with poorer arthritis outcomes. More recently, research has expanded to examine how one's neighborhood socioeconomic environment may be relevant to OA outcomes. This narrative review proposes a framework to help guide our understanding of how social context may interact with pathophysiological processes and individual-level variables to influence health outcomes in those living with OA.

Determinants of demand for total hip and knee arthroplasty: a systematic literature review

BACKGROUND

Documented age, gender, race and socio-economic disparities in total joint arthroplasty (TJA), suggest that those who need the surgery may not receive it, and present a challenge to explain the causes of unmet need. It is not clear whether doctors limit treatment opportunities to patients, nor is it known the effect that patient beliefs and expectations about the operation, including their paid work status and retirement plans, have on the decision to undergo TJA. Identifying socio-economic and other determinants of demand would inform the design of effective and efficient health policy. This review was conducted to identify the factors that lead patients in need to undergo TJA.

METHODS

An electronic search of the Embase and Medline (Ovid) bibliographic databases conducted in September 2011 identified studies in the English language that reported on factors driving patients in need of hip or knee replacement to undergo surgery. The review included reports of elective surgery rates in eligible patients or, controlling for disease severity, in general subjects, and stated clinical experts' and patients' opinions on suitability for or willingness to undergo TJA. Quantitative and qualitative studies were reviewed, but quantitative studies involving fewer than 20 subjects were excluded. The quality of individual studies was assessed on the basis of study design (i.e., prospective versus retrospective), reporting of attrition, adjustment for and report of confounding effects, and reported measures of need (self-reported versus doctor-assessed). Reported estimates of effect on the probability of surgery from analyses adjusting for confounders were summarised in narrative form and synthesised in odds ratio (OR) forest plots for individual determinants.

RESULTS

The review included 26 quantitative studies-23 on individuals' decisions or views on having the operation and three about health professionals' opinions-and 10 qualitative studies. Ethnic and racial disparities in TJA use are associated with socio-economic access factors and expectations about the process and outcomes of surgery. In the United States, health insurance coverage affects demand, including that from the Medicare population, for whom having supplemental Medicaid coverage increases the likelihood of undergoing TJA. Patients with post-secondary education are more likely to demand hip or knee surgery than those without it (range of OR 0.87-2.38). Women are as willing to undergo surgery as men, but they are less likely to be offered surgery by specialists than men with the same need. There is considerable variation in patient demand with age, with distinct patterns for hip and knee. Paid employment appears to increase the chances of undergoing surgery, but no study was found that investigated the relationship between retirement plans and demand for TJA. There is evidence of substantial geographical variation in access to joint replacement within the territory covered by a public national health system, which is unlikely to be explained by differences in preference or unmeasured need alone. The literature tends to focus on associations, rather than testing of causal relationships, and is insufficient to assess the relative importance of determinants.

CONCLUSIONS

Patients' use of hip and knee replacement is a function of their socio-economic circumstances, which reinforce disparities by gender and race originating in the doctor-patient interaction. Willingness to undergo surgery declines steeply after the age of retirement, at the time some eligible patients may lower their expectations of health status achievement. There is some evidence that paid employment independently increases the likelihood of operation. The relative contribution of variations in surgical decision making to differential access across regions within countries deserves further research that controls for clinical need and patient lifestyle preferences, including retirement decisions. Evidence on this question will become increasingly relevant for service planning and policy design in societies with ageing populations.

Cross-sectional analysis of association between socioeconomic status and utilization of primary total hip joint replacements 2006-7: Australian Orthopaedic Association National Joint Replacement Registry

BACKGROUND

The utilization of total hip replacement (THR) surgery is rapidly increasing, however few data examine whether these procedures are associated with socioeconomic status (SES) within Australia. This study examined primary THR across SES for both genders for the Barwon Statistical Division (BSD) of Victoria, Australia.

METHODS

Using the Australian Orthopaedic Association National Joint Replacement Registry data for 2006-7, primary THR with a diagnosis of osteoarthritis (OA) among residents of the BSD was ascertained. The Index of Relative Socioeconomic Disadvantage was used to measure SES; determined by matching residential addresses with Australian Bureau of Statistics census data. The data were categorised into quintiles; quintile 1 indicating the most disadvantaged. Age- and sex-specific rates of primary THR per 1,000 person years were reported for 10-year age bands using the total population at risk.

RESULTS

Females accounted for 46.9% of the 642 primary THR performed during 2006-7. THR utilization per 1,000 person years was 1.9 for males and 1.5 for females. The highest utilization of primary THR was observed in those aged 70-79 years (males 6.1, and females 5.4 per 1,000 person years). Overall, the U-shaped pattern of THR across SES gave the appearance of bimodality for both males and females, whereby rates were greater for both the most disadvantaged and least disadvantaged groups.

CONCLUSIONS

Further work on a larger scale is required to determine whether relationships between SES and THR utilization for the diagnosis of OA is attributable to lifestyle factors related to SES, or alternatively reflects geographic and health system biases. Identifying contributing factors associated with SES may enhance resource planning and enable more effective and focussed preventive strategies for hip OA.

Surveillance and management practices in tracheotomy patients

OBJECTIVES/HYPOTHESIS

To ascertain the surveillance and management practices for tracheotomy patients.

STUDY DESIGN

Survey of tracheotomy management.

METHODS

An electronically distributed 26-question survey was distributed under the auspices of the American Academy of Otolaryngology-Head and Neck Surgery Foundation.

RESULTS

There were 478 responses. The mean number of years in practice was 21.2 years (standard deviation [SD], 11.0 years). Sixty-five percent of respondents perform mainly adult tracheotomy. There is variation in surveillance patterns of immediate, postoperative, intermediate, and long-term surveillance. On average, respondents follow a fresh tracheotomy daily for about 6 days, monthly for about 3 months, and long-term surveillance every 4 months on average. Almost all respondents perform long-term surveillance during routine tracheotomy changes; 61.4% perform this surveillance with an endoscope, and a minority rely on history and examination. The mean frequency of tracheotomy tube changes was 2 months (SD, 2.2 months; median, 1.1 month; range, 0.06-12 months). Two hundred sixty-one respondents have or have used a decannulation algorithm. The vast majority, 96.2%, are comfortable with their current management practices. Over half of the respondents perceive value in a clinical practice guideline to help them with standardizing care, and 80% of respondents feel that it would assist other specialties in the care and surveillance of tracheotomy patients.

CONCLUSIONS

There is marked variability in the surveillance and management of tracheotomy patients. There exists opportunity to improve care through standardization of surveillance and management of these patients.