Social, educational, and occupational predictors of total hip replacement outcome

Predictive Factors of Pain and Functional Outcome 5-year Following Total Hip Arthroplasty: A Prospective FORCE-TJR Cohort Study

INTRODUCTION

Previous reports have identified a number of potential predictors of pain and function after total hip arthroplasty (THA). However, the results of these studies were conflicting, and most had a short follow-up after THA. The purpose of this study is to identify factors predictive of pain and function five years after THA.

PATIENTS AND METHODS

A multi-center cohort of 7,934 primary unilateral THA patients was prospectively enrolled in Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement (FORCE-TJR). Demographic data, comorbidities, and patient-reported outcome measures (PROMs) were collected pre-operatively and post-operatively at 5 years, including the Hip Injury and Osteoarthritis Outcome Score (HOOS) pain and function in daily living (ADL) scores. Multivariate logistic regression models with 95% confidence interval were used to identify independent predictors of pain and function at 5 years.

RESULTS

The patient dissatisfaction percentage was 8.2% at 5 years after THA. The multivariate regression identified the following predictive factors for the HOOS pain score at 5 years: age, educational level, insurance, smoking, race, Charlson Comorbidity Index (CCI), back pain severity, number of other lower extremity (LE) painful joints, the Knee Injury and Osteoarthritis Outcome Score (KOOS) pain severity of the ipsilateral knee, pre-operative Short-Form Health Survey 36-item (SF-36) mental component score (MCS), and HOOS pain scores. The multivariate regression identified the following predictor factors for HOOS ADL score at 5 years: body mass index, insurance, smoking, race, back pain severity, number of other LE painful joints, KOOS pain severity of ipsilateral knee, pre-op HOOS ADL, and pre-operative SF-36 MCS and SF-36 physical component score (PCS).

CONCLUSION

Overall, 8.2% of patients were dissatisfied five years after primary THA. We have identified a number of factors that predict less improvement in pain and function 5 years after THA. These potentially modifiable factors can be targeted with preoperative patient optimization programs to improve patient outcomes and satisfaction after primary THA. Knowledge of these factors that predict less improvement in pain and function can assist the surgeon and patient during shared decision-making, and in setting appropriate patient expectations pre-operatively.

Global mapping of institutional and hospital-based (Level II-IV) arthroplasty registries: a scoping review

PURPOSE

Four joint arthroplasty registries (JARs) levels exist based on the recorded data type. Level I JARs are national registries that record primary data. Hospital or institutional JARs (Level II-IV) document further data (patient-reported outcomes, demographic, radiographic). A worldwide list of Level II-IV JARs must be created to effectively assess and categorize these data.

METHODS

Our study is a systematic scoping review that followed the PRISMA guidelines and included 648 studies. Based on their publications, the study aimed to map the existing Level II-IV JARs worldwide. The secondary aim was to record their lifetime, publications' number and frequency and recognise differences with national JARs.

RESULTS

One hundred five Level II-IV JARs were identified. Forty-eight hospital-based, 45 institutional, and 12 regional JARs. Fifty JARs were found in America, 39 in Europe, nine in Asia, six in Oceania and one in Africa. They have published 485 cohorts, 91 case-series, 49 case-control, nine cross-sectional studies, eight registry protocols and six randomized trials. Most cohort studies were retrospective. Twenty-three per cent of papers studied patient-reported outcomes, 21.45% surgical complications, 13.73% postoperative clinical and 5.25% radiographic outcomes, and 11.88% were survival analyses. Forty-four JARs have published only one paper. Level I JARs primarily publish implant revision risk annual reports, while Level IV JARs collect comprehensive data to conduct retrospective cohort studies.

CONCLUSIONS

This is the first study mapping all Level II-IV JARs worldwide. Most JARs are found in Europe and America, reporting on retrospective cohorts, but only a few report on studies systematically.

Functional Outcome of Uncemented Total Hip Replacement in Low Socioeconomic Group Using Modified Harris Hip Score: A Prospective Midterm Follow-Up Study

Background Total hip replacement is a safe and effective surgery with excellent outcomes in most patients with hip arthritis. The aim of this study was to evaluate functional outcomes and complications of total hip replacement among patients with low socioeconomic status in India. Methods We assessed 50 patients whose incomes fell below the poverty line and who underwent uncemented total hip replacement. We used a modified Harris Hip Score, replacing two items (one measuring range of motion and one measuring deformity) with two new ones (one related to return to professional activity and another regarding sexual activity). Results At the final follow-up, patients' modified Harris Hip Score improved from a preoperative mean value of 13.28 (0-46) to a postoperative mean value of 88.52 (64-100), suggesting marked improvement in functional outcome (p<0.001). In total, 32 (64%) patients returned to their original profession, and 12 (24%) switched to alternate work with mild pain. All patients reported satisfaction with their sexual activity at the final follow-up. Conclusions Many patients in India whose income is below the poverty line work in manual labor professions (e.g., farmers, masons, and cobblers) that increase their risk of hip damage. Total hip replacement is beneficial for these patients, offering good personal and professional quality of life after the surgery.

Association of Unmet Social Needs With Level of Capability in People With Persistent Knee Pain

BACKGROUND

Musculoskeletal providers are increasingly recognizing the importance of social factors and their association with health outcomes as they aim to develop more comprehensive models of care delivery. Such factors may account for some of the unexplained variation between pathophysiology and level of pain intensity and incapability experienced by people with common conditions, such as persistent nontraumatic knee pain secondary to osteoarthritis (OA). Although the association of one's social position (for example, income, employment, or education) with levels of pain and capability are often assessed in OA research, the relationship between aspects of social context (or unmet social needs) and such symptomatic and functional outcomes in persistent knee pain are less clear.

QUESTIONS/PURPOSES

(1) Are unmet social needs associated with the level of capability in patients experiencing persistently painful nontraumatic knee conditions, accounting for sociodemographic factors? (2) Do unmet health-related social needs correlate with self-reported quality of life?

METHODS

We performed a prospective, cross-sectional study between January 2021 and August 2021 at a university academic medical center providing comprehensive care for patients with persistent lower extremity joint pain secondary to nontraumatic conditions such as age-related knee OA. A final 125 patients were included (mean age 62 ± 10 years, 65% [81 of 125] women, 47% [59 of 125] identifying as White race, 36% [45 of 125] as Hispanic or Latino, and 48% [60 of 125] with safety-net insurance or Medicaid). We measured patient-reported outcomes of knee capability (Knee injury and Osteoarthritis Outcome Score for Joint Replacement), quality of life (Patient-Reported Outcome Measure Information System [PROMIS] Global Physical Health and PROMIS Global Mental Health), and unmet social needs (Accountable Health Communities Health-Related Social Needs Survey, accounting for insufficiencies related to housing, food, transportation, utilities, and interpersonal violence), as well as demographic factors.

RESULTS

After controlling for demographic factors such as insurance status, education attained, and household income, we found that reduced knee-specific capability was moderately associated with experiencing unmet social needs (including food insecurity, housing instability, transportation needs, utility needs, or interpersonal safety) (standardized beta regression coefficient [β] = -4.8 [95% confidence interval -7.9 to -1.7]; p = 0.002 and substantially associated with unemployment (β = -13 [95% CI -23 to -3.8]; p = 0.006); better knee-specific capability was substantially associated with having Medicare insurance (β = 12 [95% CI 0.78 to 23]; p = 0.04). After accounting for factors such as insurance status, education attained, and household income, we found that older age was associated with better general mental health (β = 0.20 [95% CI 0.0031 to 0.39]; p = 0.047) and with better physical health (β = 0.004 [95% CI 0.0001 to 0.008]; p = 0.04), but effect sizes were small to negligible, respectively.

CONCLUSION

There is an association of unmet social needs with level of capability and unemployment in patients with persistent nontraumatic knee pain. This finding signals a need for comprehensive care delivery for patients with persistent knee pain that screens for and responds to potentially modifiable social risk factors, including those based on one's social circumstances and context, to achieve better outcomes.

LEVEL OF EVIDENCE

Level II, prognostic study.

Risk factors for pain after total hip arthroplasty: a systematic review

BACKGROUND

Approximately 23% of patients develop hip pain after total hip arthroplasty (THA). In this systematic review, we aimed to identify risk factors associated with postoperative pain after THA to optimize preoperative surgical planning.

METHODS

Six literature databases were searched for articles published from January 1995 to August 2020. Controlled trials and observational studies that reported measurements of postoperative pain with assessments of preoperative modifiable and non-modifiable risk factors were included. Three researchers performed a literature review independently.

RESULTS

Fifty-four studies were included in the study for analysis. The most consistent association between worse pain outcomes and the female sex is poor preoperative pain or function, and more severe medical or psychiatric comorbidities. The correlation was less strong between worse pain outcomes and preoperative high body mass index value, low radiographic grade arthritis, and low socioeconomic status. A weak correlation was found between age and worse pain outcomes.

CONCLUSIONS

Preoperative risk factors that were consistently predictive of greater/server postoperative pain after THA were identified, despite the varying quality of studies that prohibited the arrival of concrete conclusions. Modifiable factors should be optimized preoperatively, whereas non-modifiable factors may be valuable to patient education, shared decision-making, and individualized pain management.

Are contextual factors associated with activities and participation after total hip arthroplasty? A systematic review

OBJECTIVES

After total hip arthroplasty (THA), over 30% of individuals report activity limitations and participation restrictions. This systematic review aimed to determine the association between contextual factors and outcomes in the activity and participation domain after THA for hip osteoarthritis (OA).

METHODS

This systematic review was developed according to the PRISMA guidelines for systematic reviews. PubMed, Web of Science, Embase and Scopus were searched until August 2022. Risk of bias was assessed with the Quality in Prognosis Studies tool (QUIPS).

RESULTS

Twenty-nine articles were included. Eighteen had a high risk of bias, 3 had a low risk of bias, and 8 had a moderate risk of bias. Anxiety was only investigated in studies with high risk of bias but showed a consistent negative association with activities and participation after THA across multiple studies. Evidence was inconsistent regarding the associations between depression, trait anxiety, sense of coherence, big 5 personality traits, educational level, marital status, employment status, job position, expectations and social support, and the activity and participation domain. Optimism, general self-efficacy, cognitive appraisal processes, illness perception, ethnicity, and positive life events were associated with activities and participation but were only investigated in 1 study. No associations were identified across multiple studies for living or smoking status. Control beliefs, kinesiophobia, race, discharge location, level of poverty in neighbourhood, negative life events and occupational factors, were not associated with the activity and participation domain but were only investigated in 1 study.

CONCLUSION

Methodological quality of the included studies was low. Anxiety was the only factor consistently associated with worse outcomes in the activity and participation domain after THA but was only investigated in studies with high risk of bias. Further research is needed to confirm relationships between other contextual factors and activities and participation after THA.

REGISTRATION

PROSPERO CRD42020199070.

Do changes in outcomes following primary and revision hip replacement differ and relate to markers of socioeconomic status? A 1-year population-based cohort study

BACKGROUND AND PURPOSE

There is little evidence on improvement after revision total hip replacement (THR). Moreover, improvements may be associated with socioeconomic status (SES). We investigated whether changes in Harris Hip Score (HHS) differ among patients undergoing primary and revision THR, and their association with markers of SES.

PATIENTS AND METHODS

We conducted a populationbased cohort study on 16,932 patients undergoing primary and/or revision THR from 1995 to 2018 due to hip osteoarthritis. The patients were identified in the Danish Hip Arthroplasty Registry. Outcome was defined as mean change in HHS (0-100) from baseline to 1-year follow-up, and its association with SES markers (education, cohabiting, and wealth) was analyzed using multiple linear regression adjusting for sex, age, comorbidities, and baseline HHS.

RESULTS

At 1-year follow-up, HHS improved clinically relevant for patients undergoing both primary THR: mean 43 (95% CI 43-43) and revision THR: mean 31 (CI 29-33); however, the increase was 12 points (CI 10-14) higher for primary THR. For primary THR, improvements were 0.9 points (CI 0.4-1.5) higher for patients with high educational level compared with low educational level, 0.4 points (CI 0.0-0.8) higher for patients cohabiting compared with living alone, and 2.6 points higher (CI 2.1-3.0) for patients with high wealth compared with low wealth.

INTERPRETATION

Patients undergoing primary THR achieve higher improvements on HHS than patients undergoing revision THR, and the improvements are negatively related to markers of low SES. Health professionals should be aware of these characteristics and be able to identify patients who may benefit from extra rehabilitation to improve outcomes after THR to ensure equality in health.

Preoperative Factors and Patient-Reported Outcomes After Total Hip Arthroplasty: Multivariable Prediction Modeling

BACKGROUND

Although total hip arthroplasty (THA) has been established as a cost-effective intervention, some patients experience ongoing pain and dissatisfaction. There is interest in predicting postoperative outcomes based on preoperative data, but the relative contribution of different preoperative factors is unclear. The study's aim was to develop multivariable prediction models for the assessment of patient-reported outcomes.

METHOD

Registry data on 1412 patients undergoing THA for osteoarthritis at two hospitals between 2013 and 2018 was used. Potential predictors included age, sex, body mass index, spoken language, education level, previous THA, American Society of Anaesthesiologists (ASA) score, lower back pain, depression/anxiety, other lower limb arthritis, number of other comorbidities, the preoperative expectation of pain and function, EuroQol Visual Analogue Scale (EQ-VAS) and preoperative OHS. Radiographic scores were also used: joint space narrowing (JSN), osteophytes, sclerosis, and an overall grade based on the Kellgren-Lawrence (KL) classification. Outcomes assessed were the patient-rated improvement, satisfaction, and OHS at six months.

RESULTS

JSN or overall KL scores were the most important predictors (P < .001) for all outcomes, with better radiographic scores associated with worse outcomes. Other predictors associated with poorer outcomes were lower back pain and lower expectation (predicting poor improvement), lower education and higher ASA (predicting lower satisfaction) and younger age, female sex, non-English speakers, lower preoperative EQ-VAS, lower education, back pain, and anxiety/depression (predicting lower OHS).

CONCLUSION

Preoperative radiological scores are an important predictor of patient-reported outcomes at six months postoperatively. Understanding the relative strengths and significance of different factors in predicting outcomes will help the clinician and patient decision-making for THA.

1-year trajectories of patients undergoing primary total hip arthroplasty: Patient reported outcomes and resource needs according to education level

Background

Objectives were first to evaluate by education level one-year trajectories of pain, function and general health, as well as hospital resource and medication needs in patients undergoing primary total hip arthroplasty (THA); and second, to evaluate whether outcome differences are related to existing baseline differences in health and disease severity.

Methods

We included all primary THAs from a public hospital-based prospective arthroplasty registry, performed in a high-income country 2010 to 2017. Education was classified in three levels: ≤8years of schooling (low), 9-12years (medium), and ≥13years (high). Pain and function prior to and one-year after surgery were assessed with the Western Ontario McMaster Universities score (WOMAC) and general health with the 12-item short-form health survey (SF-12).

Results

Overall 963 patients were included, 340 (35.3%) with low, 306 (31.8%) with medium, and 317 (32.9%) with high education. With increasing educational level preoperative scores for pain, function and SF-12 mental health component increased. One year after surgery improvement was observed in all education categories for WOMAC pain and function, SF-12 mental and physical component. However, absolute postoperative scores remained lower in all four domains for the low education group. After adjustment for baseline characteristics differences were much attenuated and no longer significant. There was also greater resource need in low educated patients.

Conclusions

The inferior absolute results one year after surgery in less educated patients were largely due to older age, worse preoperative health and greater symptom severity calling for greater attention to timely and equal management, for more targeted perioperative care and increased support for the lower education group.

Effect of marital status on patient-reported outcomes following total hip arthroplasty: a matched analysis with minimum 2-year follow-up

INTRODUCTION

Mental health and patient expectation have been identified as key predictors of recovery following THA; however, there is limited literature examining the effects of social support and marital status on patient-reported outcomes (PROs).

METHODS

Data were prospectively collected and retrospectively reviewed for patients who underwent THA between July 2008 and January 2016. Patients were included if they underwent primary THA during this period and if they had documented preoperative marital status of married, divorced, or never married. Married patients were group matched to non-married patients (divorced or never married) with similar sex, age, body mass index (BMI), gender distribution, and frequency of surgical approach.

RESULTS

There were 414 married patients and 98 non-married patients who were eligible and had minimum 2-year follow-up. Mean PROs were significantly worse in the non-married group than the married group for the following measures: modified Harris Hip Score (p = 0.002), Harris Hip Score (p = 0.002), Forgotten Joint Score (p = 0.04), and the physical portions of the Veterans RAND (p = 0.025) and Short Form (p = 0.02) surveys.

CONCLUSIONS

Our study demonstrated inferior absolute PRO scores at latest follow-up for patients who were non-married compared to married following THA. These results show that while total hip replacement may still yield clinical benefit in all patients, non-married patients may ultimately achieve an inferior functional status, and expectations should be adjusted accordingly. Physicians should assess levels of psychosocial support in their patients prior to undergoing hip arthroplasty in order to optimise results.

Racial/Ethnic, Socioeconomic, and Geographic Disparities in the Epidemiology of Knee and Hip Osteoarthritis

It is estimated that 32.5 million US adults have clinical osteoarthritis (OA), with the most common sites being knee and hip. OA is associated with substantial individual and societal costs. Race/ethnicity, socioeconomic status (SES), and geographic variations in the prevalence of knee and hip OA are well established around the world. In addition, clinical outcomes associated with hip and knee OA differ according to race/ethnicity, SES, and geography. This variation is likely multifactorial and may also reflect country-specific differences in health care systems. The interplay between different factors, such as geography, SES, and race/ethnicity, is difficult to study.

Is gain in health-related quality of life after a total hip arthroplasty depended on the comorbidity burden?

Background and purpose - Using patient-reported health-related quality of life (HRQoL), approximately 10% of patients report some degree of dissatisfaction after a total hip arthroplasty (THA). The preoperative comorbidity burden may play a role in predicting which patients may have limited benefit from a THA. Therefore, we examined whether gain in HRQoL measured with the EuroQol-5D (EQ-5D) at 3 and 12 months of follow-up depended on the comorbidity burden in THA patients Patients and methods - 1,582 THA patients treated at the Regional Hospital West Jutland from 2008 to 2013 were included. The comorbidity burden was collected from an administrative database and assessed with the Charlson Comorbidity Index (CCI). The CCI was divided into 3 levels: no comorbidity burden, low, and high comorbidity burden. HRQoL was measured using the EQ-5D preoperatively and at 3 and 12 months' follow-up. Association between low and high comorbidity burden compared with no comorbidity burden and gain in HRQoL was analyzed with multiple linear regression. Results - All patients, regardless of comorbidity burden, gained significantly in HRQoL. A positive association between comorbidity burden and gain in HRQoL was found at 3-month follow-up for THA patients with a high comorbidity burden (coeff: 0.09 (95% CI 0.02 - 0.16)) compared with patients with no comorbidity burden. Interpretation - A comorbidity burden prior to THA does not preclude a gain in HRQoL up to 1 year after THA.

Cost-effectiveness of timely versus delayed primary total hip replacement in Germany: A social health insurance perspective

Without clinical guideline on the optimal timing for primary total hip replacement (THR), patients often receive the operation with delay. Delaying THR may negatively affect long-term health-related quality of life, but its economic effects are unclear. We evaluated the costs and health benefits of timely primary THR for functionally independent adult patients with end-stage osteoarthritis (OA) compared to non-surgical therapy followed by THR after progression to functional dependence (delayed THR), and non-surgical therapy alone (Medical Therapy), from a German Social Health Insurance (SHI) perspective. Data from hip arthroplasty registers and a systematic review of the published literature were used to populate a tunnel-state modified Markov lifetime model of OA treatment in Germany. A 5% annual discount rate was applied to costs (2013 prices) and health outcomes (Quality Adjusted Life Years, QALY). The expected future average cost of timely THR, delayed THR and medical therapy in women at age 55 were €27,474, €27,083 and €28,263, and QALYs were 20.7, 16.7, and 10.3, respectively. QALY differences were entirely due to health-related quality of life differences. The discounted cost per QALY gained by timely over delayed (median delay of 11 years) THR was €1270 and €1338 in women treated at age 55 and age 65, respectively, and slightly higher than this for men. Timely THR is cost-effective, generating large quality of life benefits for patients at low additional cost to the SHI. With declining healthcare budgets, research is needed to identify the characteristics of those able to benefit the most from timely THR.

Lower limb arthroplasty: can we produce a tool to predict outcome and failure, and is it cost-effective? An epidemiological study

Background

Although hip and knee arthroplasties are considered to be common elective cost-effective operations, up to one-quarter of patients are not satisfied with the operation. A number of risk factors for implant failure are known, but little is known about the predictors of patient-reported outcomes.

Objectives

(1) Describe current and future needs for lower limb arthroplasties in the UK; (2) describe important risk factors for poor surgery outcomes and combine them to produce predictive tools (for hip and knee separately) for poor outcomes; (3) produce a Markov model to enable a detailed health economic analysis of hip/knee arthroplasty, and for implementing the predictive tool; and (4) test the practicality of the prediction tools in a pragmatic prospective cohort of lower limb arthroplasty.

Design

The programme was arranged into four work packages. The first three work packages used the data from large existing data sets such as Clinical Practice Research Datalink, Hospital Episode Statistics and the National Joint Registry. Work package 4 established a pragmatic cohort of lower limb arthroplasty to test the practicality of the predictive tools developed within the programme.

Results

The estimated number of total knee replacements (TKRs) and total hip replacements (THRs) performed in the UK in 2015 was 85,019 and 72,418, respectively. Between 1991 and 2006, the estimated age-standardised rates (per 100,000 person-years) for a THR increased from 60.3 to 144.6 for women and from 35.8 to 88.6 for men. The rates for TKR increased from 42.5 to 138.7 for women and from 28.7 to 99.4 for men. The strongest predictors for poor outcomes were preoperative pain/function scores, deprivation, age, mental health score and radiographic variable pattern of joint space narrowing. We found a weak association between body mass index (BMI) and outcomes; however, increased BMI did increase the risk of revision surgery (a 5-kg/m2rise in BMI increased THR revision risk by 10.4% and TKR revision risk by 7.7%). We also confirmed that osteoarthritis (OA) severity and migration pattern of the hip predicted patient-reported outcome measures. The hip predictive tool that we developed performed well, with a correctedR2of 23.1% and had good calibration, with only slight overestimation of Oxford Hip Score in the lowest decile of outcome. The knee tool developed performed less well, with a correctedR2of 20.2%; however, it had good calibration. The analysis was restricted by the relatively limited number of variables available in the extant data sets, something that could be addressed in future studies. We found that the use of bisphosphonates reduced the risk of revision knee and hip surgery by 46%. Hormone replacement therapy reduced the risk by 38%, if used for at least 6 months postoperatively. We found that an increased risk of postoperative fracture was prevented by bisphosphonate use. This result, being observational in nature, will require confirmation in a randomised controlled trial. The Markov model distinguished between outcome categories following primary and revision procedures. The resulting outcome prediction tool for THR and TKR reduced the number and proportion of unsatisfactory outcomes after the operation, saving NHS resources in the process. The highest savings per quality-adjusted life-year (QALY) forgone were reported from the oldest patient subgroups (men and women aged ≥ 80 years), with a reported incremental cost-effectiveness ratio of around £1200 saved per QALY forgone for THRs. In the prospective cohort of arthroplasty, the performance of the knee model was modest (R2 = 0.14) and that of the hip model poor (R2 = 0.04). However, the addition of the radiographic OA variable improved the performance of the hip model (R2 = 0.125 vs. 0.110) and high-sensitivity C-reactive protein improved the performance of the knee model (R2 = 0.230 vs. 0.216). These data will ideally need replication in an external cohort of a similar design. The data are not necessarily applicable to other health systems or countries.

Conclusion

The number of total hip and knee replacements will increase in the next decade. High BMI, although clinically insignificant, is associated with an increased risk of revision surgery and postoperative complications. Preoperative pain/function, the pattern of joint space narrowing, deprivation index and level of education were found to be the strongest predictors for THR. Bisphosphonates and hormone therapy proved to be beneficial for patients undergoing lower limb replacement. The addition of new predictors collected from the prospective cohort of arthroplasty slightly improved the performance of the predictive tools, suggesting that the potential improvements in both tools can be achieved using the plethora of extra variables from the validation cohort. Although currently it would not be cost-effective to implement the predictive tools in a health-care setting, we feel that the addition of extensive risk factors will improve the performances of the predictive tools as well as the Markov model, and will prove to be beneficial in terms of cost-effectiveness. Future analyses are under way and awaiting more promising provisional results.

Future work

Further research should focus on defining and predicting the most important outcome to the patient.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Patient-reported outcomes and outcome predictors after primary total hip arthroplasty: results from the Dresden Hip Surgery Registry

PURPOSE

To investigate response rates and predictors of treatment success in patients treated with total hip arthroplasty (THA).

METHODS

A prospective register-based cohort study including all consecutive primary THAs was conducted -between 01/2006-12/2011. Primary outcomes were changes in WOMAC, according to OMERACT-OARSI, and minimal important difference (MID) in quality of life (EQ-5D) between baseline and 6-month follow-up. Socioeconomic and clinical predictors on treatment success were analysed by bivariate/multivariate regression.

RESULTS

The study population included 2,553 patients (mean age 60.8 years; 52.8% female) and 2,391 (93.7%) at follow-up. 2,194 (93.8%) (OMERACT-OARSI) and 2,131 (83.5%) (EQ-5D MID) patients were classified as responders. Predictors for treatment success vs treatment failure were not identified. Obese patients and patients living alone showed less pronounced, and patients with higher educational level more pronounced, improvements in the WOMAC at follow-up.

CONCLUSIONS

Treatment with THA leads to improvement in function, decline in pain and increase in quality of life in the vast majority of patients.

Factors associated with functional limitations in the daily living activities of Japanese hip osteoarthritis patients

AIM

As society ages, there is a vast number of elderly people with locomotive syndrome. In this study, the factors associated with functional limitations in daily living activities evaluated by female hip osteoarthritis (OA) patients were investigated.

METHODS

This study was a cross-sectional study. The subjects were 353 female patients who were newly diagnosed with hip OA at an orthopedic clinic with no history of hip joint surgery. Outcome indices were functional limitations in two daily living activities obtained from a questionnaire completed by the patients: (i) standing up (standing from a crouched position) and (ii) stair-climbing (climbing and/or descending stairs). The odds ratios (ORs) and 95% confidence intervals (CIs) were computed for explanatory variables using the proportional odds model in logistic regression to evaluate their associations with functional limitations.

RESULTS

Functional limitations in standing up were associated with heavy weight (third tertile vs. first tertile: 1.91, 1.11-3.27), participation in sports at school (0.62, 0.40-0.98), parity (vs. nullipara: 1.96, 1.08-3.56), old age and OA stage. Associations with functional limitations in stair-climbing were seen with short height (< 151.0 cm vs. ≥ 156.0 cm: 2.05, 1.02-4.12), bilateral involvement (vs. unilateral: 1.71, 1.01-2.88), old age and OA stage.

CONCLUSION

Old age, OA stage, heavy weight, parity, shorter height and bilateral OA were associated with functional limitations in standing up and/or stair-climbing, whereas participation in sports such as club activities in school maintained standing up.

Predictors of physical functioning after total hip arthroplasty: a systematic review

OBJECTIVE

The objective of this systematic review of the literature was to identify the predictors of functional outcome after total hip arthroplasty (THA).

METHOD

A systematic literature search in Web of Science, CINAHL, EMBASE and PubMed was conducted on 23 June 2015. The articles were selected based on their quality, relevance and measurement of the predictive factor. The level of evidence of all studies was determined using the GRADE rating scheme.

RESULTS

The initial search resulted in 1092 citations. After application of the inclusion and exclusion criteria, 33 articles met our eligibility criteria and were graded. Included studies were classified as level of evidence low (11), moderate (17) or high (5). Of the included studies, 18 evaluated body mass index (BMI), 17 evaluated preoperative physical functions, 15 evaluated age, 15 evaluated gender and 13 evaluated comorbidity. There was strong evidence suggesting an association between BMI, age, comorbidity, preoperative physical functions and mental health with functional outcome after THA. There was weak evidence suggesting an association between quadriceps strength and education with functional outcome after THA. The evidence was inconsistent for associations with gender and socioeconomic status and functional outcome following THA. We found limited evidence suggesting that alcohol consumption, vitamin D insufficiency and allergies were predictors of functional outcome following THA.

CONCLUSIONS

We have identified multiple predictors of functional outcome after THA, which will enable general practitioners and orthopaedic surgeons to better predict the improvement in physical functioning for their patients with THA. They can use this information to provide patient-specific advice regarding the referral for THA and the expected outcomes after THA. Further research with consistent measurement tools, outcomes and duration of follow-up across studies is needed to confirm the influence of these factors.

A new responder criterion (relative effect per patient (REPP) > 0.2) externally validated in a large total hip replacement multicenter cohort (EUROHIP)

OBJECTIVE

To validate a new method to identify responders (relative effect per patient (REPP) >0.2) using the OMERACT-OARSI criteria as gold standard in a large multicentre sample.

METHOD

The REPP ([score before - after treatment]/score before treatment) was calculated for 845 patients of a large multicenter European cohort study for THR. The patients with a REPP >0.2 were defined as responders. The responder rate was compared to the gold standard (OMERACT-OARSI criteria) using receiver operator characteristic (ROC) curve analysis for sensitivity, specificity and percentage of appropriately classified patients.

RESULTS

With the criterion REPP>0.2 85.4% of the patients were classified as responders, applying the OARSI-OMERACT criteria 85.7%. The new method had 98.8% sensitivity, 94.2% specificity and 98.1% of the patients were correctly classified compared to the gold standard.

CONCLUSION

The external validation showed a high sensitivity and also specificity of a new criterion to identify a responder compared to the gold standard method. It is simple and has no uncertainties due to a single classification criterion.

Social and Behavioral Factors in Total Knee and Hip Arthroplasty

Social and behavioral factors are important determinants of health outcomes in a number of medical conditions but their role in joint arthroplasty is poorly understood. In a cohort of 20,124 hip and knee arthroplasty procedures, smoking was associated with a significantly higher risk of surgical site infections (hazard ratio 1.7, 95% CI: 1.1-2.6), whereas alcohol use was associated with a lower risk of reoperations and revisions (hazard ratio 0.7, 95% CI: 0.5-0.8). There was no association between marital status and educational attainment with the risk of complications or reoperations in total hip and knee arthroplasty.

[Personality and comorbidity: are there "difficult patients" in hip arthroplasty?]

BACKGROUND

Concomitant disorders at the time of surgery in addition to psychological and socioeconomic patient characteristics may influence treatment outcomes in hip arthroplasty.

OBJECTIVES

To describe the impact of these factors on perioperative complications and postoperative results in terms of function, quality of life, and patient satisfaction.

MATERIALS AND METHODS

Review of relevant clinical studies, meta-analyses, and presentation of our own results.

RESULTS

Comorbidities in general, especially in combination, increase the perioperative risk profile. Socioeconomic factors (education, professional qualifications, social deprivation) in addition to psychological variables (depression, distressed personality) can have a major impact on postoperative functional outcomes and patient satisfaction.

CONCLUSIONS

It is of crucial importance to avoid inequalities in the provision of joint replacement for patients with hip osteoarthritis and co-existing risk factors. Preventive strategies should be implemented to reduce the negative impact of comorbidities on treatment outcome. Personalized communication and education may be helpful in avoiding unrealistic patient expectations before hip replacement.

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.

Outcomes following large joint arthroplasty: does socio-economic status matter?

BACKGROUND

We sought to determine whether socio-economic status (SES) is an independent predictor of outcome following total knee (TKR) and hip (THR) replacement in Australians.

METHODS

In this prospective cohort study, we included patients undergoing TKR and THR in a public hospital in whom baseline and 12-month follow-up data were available. SES was determined using the Australian Bureau of Statistics 'Index of Relative Advantage and Disadvantage'. Other independent variables included patients' demographics, comorbidities and procedure-related variables. Outcome measures were the International Knee Society Score and Harris Hip Score pain and function subscales, and the Short Form Health Survey (SF-12) physical and mental component scores.

RESULTS

Among 1,016 patients undergoing TKR and 835 patients undergoing THR, in multiple regression analysis, SES score was not independently associated with pain and functional outcomes. Female sex, older age, being a non-English speaker, higher body mass index and presence of comorbidities were associated with greater post-operative pain and poorer functional outcomes following arthroplasty. Better baseline function, physical and mental health, and lower baseline level of pain were associated with better outcomes at 12 months. In univariate analysis, for TKR, the improvement in SF-12 mental health score post arthroplasty was greater in patients of lower SES (3.8 ± 12.9 versus 1.5 ± 12.2, p=0.008), with a statistically significant inverse association between SES score and post-operative SF-12 mental health score in linear regression analysis (coefficient-0.28, 95% CI: -0.52 to -0.04, p=0.02).

CONCLUSIONS

When adjustments are made for other covariates, SES is not an independent predictor of pain and functional outcome following large joint arthroplasty in Australian patients. However, relative to baseline, patients in lower socioeconomic groups are likely to have greater mental health benefits with TKR than more privileged patients. Large joint arthroplasty should be made accessible to patients of all SES.

Independent associations of socioeconomic factors with disability and pain in adults with knee osteoarthritis

BACKGROUND

The purpose of this study is to explore the relationship between function, pain and stiffness outcomes with individual and community socioeconomic status (SES) measures among individuals with radiographic knee osteoarthritis (rOA).

METHODS

Cross-sectional data from the Johnston County Osteoarthritis Project were analyzed for adults age 45 and older with knee rOA (n = 782) and a subset with both radiographic and symptomatic knee OA (n = 471). Function, pain and stiffness were measured using the Western Ontario and McMasters Universities Index of Osteoarthritis (WOMAC). Individual SES measures included educational attainment (<12 years, ≥12 years) and occupation type (managerial, non-managerial), while community SES was measured using Census block group poverty rate (<12%, 12-25%, ≥25%). SES measures were individually and simultaneously examined in linear regression models adjusting for age, gender, race, body mass index (BMI), occupational physical activity score (PAS), comorbidity count, and presence of hip symptoms.

RESULTS

In analyses among all individuals with rOA, models which included individual SES measures were observed to show that occupation was significantly associated with WOMAC Function (β =2.91, 95% Confidence Interval (CI) = 0.68-5.14), WOMAC Pain (β =0.93, 95% CI = 0.26-1.59) and WOMAC Total scores (β =4.05, 95% CI = 1.04-7.05), and education was significantly associated with WOMAC Function (β =3.57, 95% CI = 1.25-5.90) and WOMAC Total (β =4.56, 95% CI = 1.41-7.70) scores. In multivariable models including all SES measures simultaneously, most associations were attenuated. However, statistically significant results for education remained between WOMAC Function (β =2.83, 95% CI = 0.38-5.28) and WOMAC Total (β =3.48, 95% CI = 0.18-6.78), as well as for the association between occupation and WOMAC Pain (β =0.78, 95% CI = 0.08-1.48). In rOA subgroup analyses restricted to those with symptoms, we observed a significant increase in WOMAC Pain (β =1.36, 95% CI = 0.07-2.66) among individuals living in a block group with poverty rates greater than 25%, an association that remained when all SES measures were considered simultaneously (β =1.35, 95% CI = 0.06-2.64).

CONCLUSIONS

Lower individual and community SES are both associated with worse function and pain among adults with knee rOA.

[More muscle mass in men: explanatory model for superior outcome after total hip arthroplasty]

BACKGROUND

Men show better functional results after total hip arthroplasty (THA). The aim of this study was a patient-specific analysis of the hip joint muscles in comparison to the joint geometry.

METHODS

In this study 93 computed tomography (CT) scans of the pelvis (45 men, 48 women) were analyzed to determine hip joint geometry and the volume of the gluteus medius (GMV), gluteus maximus (GXV) and tensor fasciae latae (TFL) muscles. The abduction muscle volumes were analyzed with respect to patient-specific adduction moments.

RESULTS

The absolute total volume of the hip muscular system (TMV) was larger in men than in women (1913 ccm vs. 1479 ccm; p <0.0001). Men exhibited a more progressive increase of muscle volume as the adduction moment increases.

CONCLUSIONS

Men have a greater abduction muscle mass in order to balance adduction moments occurring in the hip joint and therefore have more muscle mass to compensate the inevitable intraoperative muscle damage during THA. This argument supports the extraordinary importance of muscle sparing surgical techniques in women.

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.

Nonparticipation in a Danish cohort study of long-term sickness absence

AIM

The aim of the present study was to identify predictors of nonparticipation in a Danish cohort of individuals on long-term sickness absence with a nonparticipation rate of 53.6%.

METHODS

Data from Danish public registers were linked to all 2414 individuals initially recruited to the cohort. Information regarding social- and health-related characteristics was retrieved. Adjusted logistic regression was carried out to examine differences between participants and nonparticipants as well as to identify predictors of nonparticipation.

RESULTS

Nonparticipation was associated with being male, relatively young, having a vocational secondary education, and having a low income, whereas a recent somatic disease treated in hospital was a predictor for participation. Having had a psychiatric disorder in the past was generally a barrier for participation, while a recent psychiatric disorder was a positive factor for participation.

CONCLUSION

Individuals with low socioeconomic status and individuals with prior psychiatric disorders were less willing to participate in this cohort study of long-term sickness absence.

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 pain and functioning in hip osteoarthritis - a two-year prospective study

OBJECTIVE

To identify predictors of pain and disability in hip osteoarthritis.

DESIGN

A prospective analysis of determinants of pain and functioning in hip osteoarthritis.

STUDY SETTING

Rehabilitation clinic in a central hospital.

PATIENTS

A total of 118 men and women aged 55-80 years who had radiologically diagnosed hip osteoarthritis and associated clinical symptoms and participated in a randomized controlled trial.

MAIN MEASURES

The self-reported disease-specific pain and physical function were assessed using the pain and functioning subscales of the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis index. The self-reported generic physical and mental functioning were assessed by using the Finnish-validated SF-36-item Health Survey RAND-36 subscales for function and physical and mental component summary scores. Outcome measures were recorded at 0, 3, 6, 12, 18 and 24 months.

RESULTS

Multivariate linear mixed model analyses revealed that lower disease-specific pain score and better functioning (WOMAC) were predicted by higher educational level (9.61 (3.15 to 16.07); 9.07 (2.05 to 16.09)), supervised exercise training (-10.13 (-17.87 to -2.39); -11.58 (-19.40 to -3.77)), habitual conditioning physical activity (-0.48 (-0.96 to -0.01); -0.39 (-0.84 to 0.05)), absence of comorbidities (-6.30 (-12.35 to -0.24); -7.87 (-14.45 to -1.30)) and absence of additional knee osteoarthritis (-7.62 (-13.87 to -1.36); -8.02 (-14.81 to -1.23)), respectively. The same factors, except for the comorbidities, also predicted general physical functioning score (RAND-36).

CONCLUSIONS

Higher education, absence of knee osteoarthritis and comorbidities, supervised exercise training and habitual conditioning physical activity predicted a lower presence of pain and better functional status in patients with hip osteoarthritis.

The association of disability and pain with individual and community socioeconomic status in people with hip osteoarthritis

Objective:

To examine associations between disability and socioeconomic status (SES) in persons with hip radiographic OA (rOA) or symptomatic OA (sxOA) in the Johnston County Osteoarthritis Project.

Methods:

Cross-sectional analyses were conducted on individuals with hip rOA (708) or sxOA (251). rOA was defined as Kellgren-Lawrence ≥ 2. Educational attainment (<12 years or ≥12 years) and occupation (managerial or non-managerial) were individual SES measures. Census block group poverty rate (<12%, 12-25%, ≥25%) was the community SES measure. Disability was measured by the HAQ-DI and the WOMAC (function, pain, total). Covariates included age, gender, race, BMI, and presence of knee symptoms. Analyses examined associations of disability with each SES effect separately, followed by multivariable analyses using all SES variables, adjusting for covariates.

Results:

In models with single SES variables adjusted for covariates, WOMAC scores were associated significantly (p<0.05) with low educational attainment and non-managerial occupation in rOA and sxOA. HAQ was significantly associated with low educational attainment in rOA and sxOA and with high community poverty in rOA. In models including all SES variables, the patterns of association were similar although with diminished significance. There was indication that education was more strongly associated with HAQ and WOMAC function, while occupation was more strongly associated with WOMAC pain.

Conclusion:

Our data provide evidence that individual SES is an important factor to consider when examining disability and pain outcomes in older adults with hip OA.