Rehabilitation After Total Knee Arthroplasty: Do Racial Disparities Exist?

Race and ethnic disparities arthroplasty trends and hotspots: Bibliometric analysis

Introduction

Despite continual advancements in total joint arthroplasty and perioperative optimization, there remains national variability in outcomes. These outcome variabilities have been in part attributed to racial and ethnic disparities in healthcare quality and access to care. This study aims to identify arthroplasty racial and ethnic disparities research and to predict future hotspots.

Methods

Ethnic and racial disparities articles between 1992 and 2022 were queried from the Web of Science Core Collection of Clarivate Analytics. Bibliometric indicators in excel format were extracted and subsequently imported for further analysis. Bibliometrix and VOSviewer analyzed current and previous research.

Results

Database search yielded 234 total articles assessing racial and ethnic disparities between 1992 and 2022. Twenty-six countries published manuscripts with the United States producing the majority of publications. The Veterans Health Administration and University of Pittsburgh were the most relevant institutions. Ibrahim SA was the most relevant and influential author within this field. Visuals of thematic map and co-occurrences identified the basic, motor, and niche themes within the literature.

Conclusions

Racial and ethnic disparity within arthroplasty literature demonstrate growing traction with global contributions. United States authors and institutions are the largest contributors within this field. This bibliometric analysis identified previous, current, and future trends for prediction of future hotspots.

Impact of the Comprehensive Care for Joint Replacement Bundled Payment Model on Postoperative Utilization of Home Health and Outpatient Physical Therapy Services

OBJECTIVE

To study the effect of the Comprehensive Care for Joint Replacement (CJR) bundled payment program on postoperative home health and outpatient physical therapy (PT) for total hip or knee arthroplasty (THA/TKA).

DESIGN

Retrospective cohort with national Medicare data (5% claims) using a difference-in-differences analysis comparing January 2013-September 2015 (before) versus October 2016-September 2019 (after).

SETTING

Administrative claims from hospitals in 34 metropolitan statistical areas with mandatory CJR participation as of 2018 and 42 control metropolitan statistical areas.

PARTICIPANTS

Episodes in fee-for-service Medicare beneficiaries (5% claims) undergoing elective THA (n=6327) or TKA (n=10,764) with community discharge.

INTERVENTIONS

Implementation of CJR bundled payment program.

MAIN OUTCOME MEASURES

Home health and outpatient PT, including any use and number of visits.

RESULTS

Program implementation was associated with an increased percentage of THA episodes using home health PT (+8.0 percentage-point change; 95% CI, +3.5 to +12.6; P=.001) but a decreased per-episode number of home health PT visits for THA (-1.1; 95% CI, -1.6 to -0.6; P<.001) and TKA (-1.1; 95% CI, -1.4 to -0.7; P<.001). The program was also associated with an increased per-episode number of outpatient PT visits for TKA in the primary but not sensitivity analyses (+0.8; 95% CI, +0.1 to +1.4; P=.02).

CONCLUSIONS

Findings of increased home health PT may reflect an intentional shift in care from the inpatient postacute setting to the community to decrease costs. Alternatively, the limited effect of CJR, particularly on outpatient PT, could reflect challenges with care coordination in a retrospective bundle spanning multiple care settings.

Positive COVID-19 Diagnosis Following Primary Elective Total Joint Arthroplasty: Increased Complication and Mortality Rates

BACKGROUND

This study analyzed complication rates following primary elective total joint arthroplasty (TJA) in patients who subsequently contracted COVID-19.

METHODS

A large national database was queried for adult patients who underwent primary elective TJA in 2020. Patients who contracted COVID-19 after total knee arthroplasty (TKA) or total hip arthroplasty (THA) underwent 1:6 matching (age [±6 years], sex, month of surgery, COVID-19-related comorbidities) to patients who did not. Differences between groups were assessed using univariate and multivariate analyses. Overall, 712 COVID-19 patients were matched to 4,272 controls (average time to diagnosis: 128-117 days [range, 0-351]).

RESULTS

Of patients diagnosed <90 days postoperatively, 32.5%-33.6% required COVID-19-driven readmission. Discharge to a skilled nursing facility (adjusted odds ratio [aOR] 1.72, P = .003) or acute rehabilitation unit (aOR 4.93, P < .001) and Black race (aOR 2.28, P < .001) were associated with readmission after TKA. Similar results were associated with THA. COVID-19 patients were at increased risk of pulmonary embolism (aOR 4.09, P = .001) after TKA and also periprosthetic joint infection (aOR 4.65, P < .001) and sepsis (aOR 11.11, P < .001) after THA. The mortality rate was 3.51% in COVID-19 patients and 7.94% in readmitted COVID-19 patients compared to 0.09% in controls, representing a 38.7 OR and 91.8 OR of death, respectively. Similar results were observed for TKA and THA separately.

CONCLUSION

Patients who contracted COVID-19 following TJA were at greater risk of numerous complications, including death. These patients represent a high-risk cohort who may require more aggressive medical interventions. Given the potential limitations presently, prospectively collected data may be warranted to validate these findings.

The Effect of Education Planned According to Health Literacy Level on Functionality, Problems Experienced, and Quality of Life in Patients Undergoing Total Knee Replacement: A Nonrandomized Comparison Group Intervention Study

Total knee arthroplasty procedures significantly improve quality of life for persons with debilitating pain. It is essential to plan patient education according to the level of health literacy. This nonrandomized comparison group intervention study examines the effect of education planned according to health literacy level on functionality, postoperative problems (pain and anxiety), and quality of life in patients who undergo total knee replacement. During the study, patients in the intervention group (n = 51) were provided with the planned patient education according to their health literacy level, whereas patients in the comparison group were given routine care (n = 51). Patients in the postoperative intervention group experienced fewer problems (p < .05). Education tailored to patients' health literacy levels had a positive effect on their functionality and quality of life (p < .05). Our findings suggest planning education according to patient health literacy levels may have a positive influence on functionality, postoperative problems, and quality of life among patients undergoing total knee replacement.

Racial/Ethnic Disparities in Physical Therapy Utilization After Total Knee Arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) is a common orthopaedic procedure, after which many patients benefit from physical therapy (PT). However, such services may not be uniformly accessible and used. To that end, disparities in access to care such as PT after interventions may be a factor for those of varying race/ethnicities.

METHODS

TKAs were abstracted from the 2014 to 2016 Standard Analytic Files PearlDiver data set-a large national health administrative data set containing information on more than 60 million Medicare patients. Occurrences of home or outpatient PT within 90 days after TKA were identified. Patient demographic factors were extracted, including age, sex, Elixhauser Comorbidity Index, estimated average household income of patient based on zip code (low average household income [<75k/year] or high average household income [>75k/year]), and patient race/ethnicity (White, Hispanic, Asian, Native American, Black, or Other). Predictive factors for PT utilization were determined and compared with univariate and multivariate analyses.

RESULTS

Of 23,953 TKA patients identified, PT within 90 days after TKA was used by 18,837 (78.8%). Patients self-identified as White (21,824 [91.1%]), Black (1,250 [5.2%]), Hispanic (268 [1.1%]), Asian (241 [1.0%]), Native American (90 [0.4%]), or "Other" (280 [1.2%]) and were of low household income (19,957 [83.3%]) or high household income (3,994 [16.7%]). When controlling for age, sex, and ECI, PT was less likely to be received by those of low household income (relative to high household income OR 0.79) or by those of defined race/ethnicity (relative to White or Black OR 0.81, Native American OR 0.58, Asian OR 0.50, or Hispanic OR 0.44) ( P < 0.05 for each).

DISCUSSION

In a large Medicare data set, disparities in utilization of PT after TKA were identified based on patient's estimated household income and race/ethnicity. Identification of such factors may help facilitate the expansion of care to meet the needs of all groups adequately.

LEVEL OF EVIDENCE

Level III.

Racial and Ethnic Disparities in Total Joint Arthroplasty Care: A Contemporary Systematic Review and Meta-Analysis

BACKGROUND

Total joint arthroplasty (TJA) is one of the most common surgical procedures in the United States; however, racial and ethnic disparities in utilizations and outcomes have been well documented. This systematic review and meta-analysis investigated associations between race/ethnicity and several metrics in total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

In August 2021, PubMed, Scopus, CINAHL, and SPORTDiscus databases were queried. Sixty three studies investigating racial/ethnic disparities in TJA utilizations, complications, mortalities, lengths of stay (LOS), discharge dispositions, readmissions, and reoperations were included. Study quality was assessed using a modified Newcastle-Ottawa Scale.

RESULTS

A majority of studies demonstrated disparities in TJA utilizations and outcomes. Black patients exhibited higher rates of 30-day complications (THA odds ratio [OR] 1.18, 95% confidence interval [CI] 1.08-1.29; TKA OR 1.20, 95% CI 1.10-1.31), 30-day mortality (THA OR 1.27, 95% CI 1.08-1.48), prolonged LOS (THA mean difference [MD] +0.27 days, 95% CI 0.21-0.33; TKA MD +0.30 days, 95% CI 0.20-0.40), nonhome discharges (THA OR 1.47, 95% CI 1.37-1.57; TKA OR 1.65, 95% CI 1.38-1.96), and 30-day readmissions (THA OR 1.13, 95% CI 1.08-1.19; TKA OR 1.19, 95% CI 1.16-1.21) than White patients. Rates of complications (THA 1.18, 95% CI 1.03-1.36), prolonged LOS (TKA MD +0.20 days, 95% CI 0.17-0.23), and nonhome discharges (THA OR 1.26, 95% CI 1.10-1.45; TKA OR 1.37, 95% CI 1.22-1.53) were also increased among Hispanic patients, while Asian patients experienced longer LOS (TKA MD +0.09 days, 95% CI 0.05-0.12) but fewer readmissions. Outcomes among American Indian-Alaska Native and Pacific Islander patients were infrequently reported but similarly inequitable.

CONCLUSION

Racial and ethnic disparities in TJA utilizations and outcomes are apparent, with minority patients often demonstrating lower rates of utilizations and worse postoperative outcomes than White patients. Continued research is needed to evaluate the efficacy of recent efforts dedicated to eliminating inequalities in TJA care.

LEVEL OF EVIDENCE

IV.

Rehabilitation for Total Knee Arthroplasty: A Systematic Review

ABSTRACT

We sought to determine the comparative benefit and harm of rehabilitation interventions for patients who have undergone elective, unilateral total knee arthroplasty for the treatment of primary osteoarthritis. We searched PubMed, Embase, The Cochrane Register of Clinical Trials, CINAHL, PsycINFO, Scopus, and ClinicalTrials.gov from January 1, 2005, through May 3, 2021. We included randomized controlled trials and adequately adjusted nonrandomized comparative studies of rehabilitation programs reporting performance-based, patient-reported, or healthcare utilization outcomes. Three researchers extracted study data and assessed risk of bias, verified by an independent researcher. The team assessed strength of evidence. Evidence from 53 studies randomized controlled trials suggests that various rehabilitation programs after total knee arthroplasty may lead to comparable improvements in pain, range of motion, and activities of daily living. Rehabilitation in the acute phase may lead to increased strength but result in similar strength when delivered in the postacute phase. No studies reported evidence of risk of harms due to rehabilitation delivered in the acute period after total knee arthroplasty; risk of harms among various postacute rehabilitation programs seems comparable. All findings were of low strength of evidence. Evaluation of rehabilitation after total knee arthroplasty needs a systematic overhaul to sufficiently guide future practice or research including the use of standardized intervention components and core outcomes.

Racial Differences in Manipulation Under Anesthesia Rates Following Total Knee Arthroplasty

BACKGROUND

Despite the extensive literature on racial disparities in care and outcomes after total knee arthroplasty (TKA), data on manipulation under anesthesia (MUA) is lacking. We aimed to determine (1) the relationship between race and rate of (and time to) MUA after TKA, and (2) annual trends in racial differences in MUA from 2013 to 2018.

METHODS

This retrospective cohort study (using 2013-2018 Medicare Limited Data Set claims data) included 836,054 primary TKA patients. The primary outcome was MUA <1 year after TKA; time from TKA to MUA in days was also recorded. A mixed-effects multivariable model measured the association between race (White, Black, Other) and odds of MUA. Odds ratios (OR) and 95% confidence intervals (CI) were reported. A Cochran Armitage Trend test was conducted to assess MUA trends over time, stratified by race.

RESULTS

MUA after TKA occurred in 1.7%, 3.2% and 2.1% of White, Black, and Other race categories, respectively (SMD = 0.07). After adjustment for covariates, (Black vs White) patients had increased odds of requiring an MUA after TKA: odds ratio (OR) 1.97, 95% confidence intervals (CI) 1.86-2.10, P < .0001. Moreover, White (compared to Black) patients had significantly shorter time to MUA after TKA: 60 days (interquartile range [IQR] 46-88) versus 64 days (interquartile range [IQR] 47-96); P < .0001. These disparities persisted from 2013 through 2018.

CONCLUSION

Continued racial differences exist for rates and timing of MUA following TKA signifying the continued need for efforts aimed toward understanding and eliminating inequalities that exist in total joint arthroplasty (TJA) care.

Psychotropic medication use and Parkinson's disease risk amongst older women

OBJECTIVE

To examine associations of antidepressant, anxiolytic and hypnotic use amongst older women (≥65 years) with incident Parkinson's Disease (PD), using data from Women's Health Initiative linked to Medicare claims.

METHODS

PD was defined using self-report, first diagnosis, medications and/or death certificates and psychotropic medications were ascertained at baseline and 3-year follow-up. Cox regression models were constructed to calculate adjusted hazard ratios (aHR) with 95% confidence intervals (CI), controlling for socio-demographic, lifestyle and health characteristics, overall and amongst women diagnosed with depression, anxiety and/or sleep disorders (DASD).

RESULTS

A total of 53,996 WHI participants (1,756 PD cases)-including 27,631 women diagnosed with DASD (1,137 PD cases)-were followed up for ~14 years. Use of hypnotics was not significantly associated with PD risk (aHR = 0.98, 95% CI: 0.82, 1.16), whereas PD risk was increased amongst users of antidepressants (aHR = 1.75, 95% CI: 1.56, 1.96) and anxiolytics (aHR = 1.48, 95% CI: 1.25, 1.73). Compared to non-users of psychotropic medications, those who used 1 type had ~50% higher PD risk, whereas those who used ≥2 types had ~150% higher PD risk. Women who experienced transitions in psychotropic medication use ('use to non-use' or 'non-use to use') between baseline and 3-year follow-up had higher PD risk than those who did not. We obtained similar results with propensity scoring and amongst DASD-diagnosed women.

INTERPRETATION

The use of antidepressants, anxiolytics or multiple psychotropic medication types and transitions in psychotropic medication use was associated with increased PD risk, whereas the use of hypnotics was not associated with PD risk amongst older women.

Racial Differences in Care and Outcomes After Total Hip and Knee Arthroplasties: Did the Comprehensive Care for Joint Replacement Program Make a Difference?

BACKGROUND

There is a paucity of literature on racial differences across a full total joint arthroplasty (TJA) "episode of care" and beyond. Given various incentives, the Comprehensive Care for Joint Replacement (CJR) program in the U.S. may have impacted preexisting racial differences across this care continuum. The purposes of the present study were (1) to assess trends in racial differences in care/outcome characteristics before, during, and after TJA surgery and (2) to assess if the CJR program coincided with reductions in these racial differences.

METHODS

This retrospective cohort study includes data on 1,483,221 TJAs (based on Medicare claims data, 2013 to 2018). Racial differences between Black and White patients were assessed for (1) preoperative characteristics (Deyo-Charlson comorbidity index, patient sex, and age), (2) characteristics during hospitalization (length of stay, blood transfusions, and combined complications), and (3) postoperative characteristics (90 and 180-day readmission rates and institutional post-acute care). Additionally, Medicare payments for each period were assessed. Racial differences (Black versus White patients) were expressed in terms of odds ratios (ORs) and 95% confidence intervals (CIs) per year. A "difference-in-differences" analysis (comparing before and after CJR implementation, with non-CJR hospitals being used as controls) estimated the association of the CJR program with changes in racial differences.

RESULTS

In both 2013 and 2018, Black patients (n = 74,390; 5.0%) were more likely than White patients to have a higher Deyo-Charlson comorbidity index (score of >0) (OR = 1.32 [95% CI = 1.28 to 1.36] and OR = 1.32 [95% CI = 1.28 to 1.37]), to require more transfusions (OR = 1.55 [95% CI = 1.49 to 1.62] and OR = 1.77 [95% CI = 1.56 to 2.01]), to be discharged to institutional post-acute care (OR = 1.40 [95% CI = 1.36 to 1.44] and OR = 1.49 [95% CI = 1.43 to 1.56]), and to be readmitted within 90 days (OR = 1.38 [95% CI = 1.32 to 1.44] and OR = 1.21 [95% CI = 1.13 to 1.29]) (p < 0.05 for all). Adjusted difference-in-differences analyses demonstrated that the CJR program coincided with reductions in racial differences in 90-day readmission (-1.24%; 95% CI, -2.46% to -0.03%) and 180-day readmission (-1.28%; 95% CI, -2.52% to -0.03%) (p = 0.044 for both).

CONCLUSIONS

Racial differences persist among patients managed with TJA. The CJR program coincided with reductions in some racial differences, thus identifying bundle design as a potential novel strategy to target racial disparities.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Race, Utilization, and Outcomes in Total Hip and Knee Arthroplasty: A Systematic Review on Health-Care Disparities

BACKGROUND

Previous studies have shown that utilization and outcomes of total joint arthroplasty (TJA) are not equivalent across different patient cohorts. This systematic review was designed to evaluate the currently available evidence regarding the effect that patient race has, if any, on utilization and outcomes of lower-extremity arthroplasty in the United States.

METHODS

A literature search of the MEDLINE database was performed using keywords such as "disparities," "arthroplasty," "race," "joint replacement," "hip," "knee," "inequities," "inequalities," "health," and "outcomes" in all possible combinations. All English-language studies with a level of evidence of I through IV published over the last 20 years were considered for inclusion. Quantitative and qualitative analyses were performed on the collected data.

RESULTS

A total of 82 articles were included. There was a significantly lower utilization rate of lower-extremity TJA among Black, Hispanic, and Asian patients compared with White patients (p < 0.05). Black and Hispanic patients had lower expectations regarding postoperative outcomes and their ability to participate in various activities after surgery, and they were less likely than White patients to be familiar with the arthroplasty procedure prior to presentation to the orthopaedic surgeon (p < 0.05). Black patients had increased risks of major complications, readmissions, revisions, and discharge to institutional care after TJA compared with White patients (p < 0.05). Hispanic patients had increased risks of complications (p < 0.05) and readmissions (p < 0.0001) after TJA compared with White patients. Black and Hispanic patients reached arthroplasty with poorer preoperative functional status, and all minority patients were more likely to undergo TJA at low-quality, low-volume hospitals compared with White patients (p < 0.05).

CONCLUSIONS

This systematic review shows that lower-extremity arthroplasty utilization differs by racial/ethnic group, and that some of these differences may be partly explained by patient expectations, preferences, and cultural differences. This study also shows that outcomes after lower-extremity arthroplasty differ vastly by racial/ethnic group, and that some of these differences may be driven by differences in preoperative functional status and unequal access to care.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Chronic Pain Prevalence and Factors Associated With High Impact Chronic Pain following Total Joint Arthroplasty: An Observational Study

Hip, knee, and shoulder arthroplasty are among the most frequently performed orthopaedic procedures in the United States. High impact and bothersome chronic pain rates following total joint arthroplasty (TJA) are unknown; as are factors that predict these chronic pain outcomes. This retrospective observational study included individuals that had a TJA from January 2014 to January 2020 (n = 2,638). Pre-operative and clinical encounter information was extracted from the electronic health record and chronic pain state was determined by email survey. Predictor variables included TJA location, number of surgeries, comorbidities, tobacco use, BMI, and pre-operative pain intensity. Primary outcomes were high impact and bothersome chronic pain. Rates of high impact pain (95% CI) were comparable for knee (9.8-13.3%), hip (8.3-11.8%) and shoulder (7.6-16.3%). Increased risk of high impact pain included non-white race, two or more comorbidities, age less than 65 years, pre-operative pain scores 5/10 or higher, knee arthroplasty, and post-operative survey completion 24 months or less. Rates of bothersome chronic pain (95% CI) were also comparable for knee (24.9-29.9%) and hip (21.3-26.3%) arthroplasty; but higher for shoulder (26.9-39.6%). Increased risk of bothersome chronic pain included non-white race, shoulder arthroplasty, knee arthroplasty, current or past tobacco use, and being female. PERSPECTIVE: In this cohort more than 1/3rd of individuals reported high impact or bothersome chronic pain following TJA. Non-white race and knee arthroplasty were the only two variables associated with both chronic pain outcomes.

Predictors of Disparities in Patient-Reported Outcomes before and after Arthroscopic Meniscectomy

The purpose of this study is to identify predictors of disparities in patient-reported outcome measures (PROMs) before and after arthroscopic meniscectomy. Knee injury and Osteoarthritis Outcome Score (KOOS) was used in this study. All patients who underwent single-knee arthroscopic meniscectomy from January 2012 to March 2018 performed by a single surgeon at an academic safety-net hospital were identified. We excluded patients who had undergone ipsilateral previous knee surgery, bilateral meniscectomy, or concomitant ligament, cartilage, or osteotomy procedures, and those with severe radiographic osteoarthritis in the operated knee, missing preoperative data, or military insurance. Data abstracted from medical records included demographics (age, sex, race, insurance type), clinical characteristics (body mass index, Charlson comorbidity index, and Kellgren-Lawrence [KL] grade), procedure codes, and KOOS assessed before and 90 days after surgery. Multivariable analyses investigated the associations between patient characteristics and the KOOS Pain, other Symptoms, and Function in activities of daily living (ADL) subscales. Among 251 eligible patients, most were female (65.5%), half were of nonwhite race (50.2%), and almost one third were insured by Medicaid (28.6%). Medicaid and black race were statistically significant (p < 0.05) predictors of worse preoperative values for all three KOOS subscales. Medicaid insurance also predicted a lower likelihood of successful surgery, defined as meeting the 10-point minimal clinically important difference, for the KOOS symptoms (p < 0.05) and KOOS ADL (p < 0.05) subscales. Compared with patients without definitive evidence of radiographic osteoarthrosis (KL grade 1), those with moderate radiographic osteoarthritis (KL grade 3) were less likely to have a successful surgical outcome (p < 0.05 for all subscales). Worse preoperative KOOS values predicted worse postoperative KOOS values (p < 0.001 for all subscales) and a lower likelihood of surgical success (p < 0.01 for all subscales). Insurance-based disparities in access to orthopaedic care for meniscus tears may explain worse preoperative PROMs and lower success rates of meniscectomy among Medicaid patients. Patients with meniscus tears and radiological and/or magnetic resonance imaging evidence of osteoarthritis should be carefully evaluated to determine the appropriateness of arthroscopic meniscectomy.

Association of the Comprehensive Care for Joint Replacement Model With Disparities in the Use of Total Hip and Total Knee Replacement

IMPORTANCE

The Comprehensive Care for Joint Replacement (CJR) model is Medicare's mandatory bundled payment reform to improve quality and spending for beneficiaries who need total hip replacement (THR) or total knee replacement (TKR), yet it does not account for sociodemographic risk factors such as race/ethnicity and income. Results of this study could be the basis for a Medicare payment reform that addresses inequities in joint replacement care.

OBJECTIVE

To examine the association of the CJR model with racial/ethnic and socioeconomic disparities in the use of elective THR and TKR among older Medicare beneficiaries after accounting for the population of patients who were at risk or eligible for these surgical procedures.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used the 2013 to 2017 national Medicare data and multivariable logistic regressions with triple-differences estimation. Medicare beneficiaries who were aged 65 to 99 years, entitled to Medicare, alive at the end of the calendar year, and residing either in the 67 metropolitan statistical areas (MSAs) mandated to participate in the CJR model or in the 104 control MSAs were identified. A subset of Medicare beneficiaries with a diagnosis of arthritis underwent THR or TKR. Data were analyzed from March to December 2020.

EXPOSURES

Implementation of the CJR model in 2016.

MAIN OUTCOMES AND MEASURES

Outcomes were separate binary indicators for whether a beneficiary underwent THR or TKR. Key independent variables were MSA treatment status, pre- or post-CJR model implementation phase, combination of race/ethnicity (non-Hispanic White, non-Hispanic Black, and Hispanic beneficiaries) and dual eligibility, and their interactions. Logistic regression models were used to control for patient characteristics, MSA fixed effects, and time trends.

RESULTS

The 2013 cohort included 4 447 205 Medicare beneficiaries, of which 2 025 357 (45.5%) resided in MSAs with the CJR model. The cohort's mean (SD) age was 77.18 (7.95) years, and it was composed of 2 951 140 female (66.4%), 3 928 432 non-Hispanic White (88.3%), and 657 073 dually eligible (14.8%) beneficiaries. Before the CJR model implementation, rates were highest among non-Hispanic White non-dual-eligible beneficiaries at 1.25% (95% CI, 1.24%-1.26%) for THR use and 2.28% (95% CI, 2.26%-2.29%) for TKR use in MSAs with CJR model. Compared with MSAs without the CJR model and the analogous race/ethnicity and dual-eligibility group, the CJR model was associated with a 0.10 (95% CI, 0.05-0.15; P < .001) percentage-point increase in TKR use for non-Hispanic White non-dual-eligible beneficiaries, a 0.11 (95% CI, 0.004-0.21; P = .04) percentage-point increase for non-Hispanic White dual-eligible beneficiaries, a 0.15 (95% CI, -0.29 to -0.01; P = .04) percentage-point decrease for non-Hispanic Black non-dual-eligible beneficiaries, and a 0.18 (95% CI, -0.34 to -0.01; P = .03) percentage-point decrease for non-Hispanic Black dual-eligible beneficiaries. These CJR model-associated changes in TKR use were 0.25 (95% CI, -0.40 to -0.10; P = .001) percentage points lower for non-Hispanic Black non-dual-eligible beneficiaries and 0.27 (95% CI, -0.45 to -0.10; P = .002) percentage points lower for non-Hispanic Black dual-eligible beneficiaries compared with the model-associated changes for non-Hispanic White non-dual-eligible beneficiaries. No association was found between the CJR model and a widening of the THR use gap among race/ethnicity and dual eligibility groups.

CONCLUSIONS AND RELEVANCE

Results of this study indicate that the CJR model was associated with a modest increase in the already substantial difference in TKR use among non-Hispanic Black vs non-Hispanic White beneficiaries; no difference was found for THR. These findings support the widespread concern that payment reform has the potential to exacerbate disparities in access to joint replacement care.

Racial/Ethnic Disparities in Physical Function Before and After Total Knee Arthroplasty Among Women in the United States

IMPORTANCE

Although racial/ethnic differences in functional outcomes after total knee arthroplasty (TKA) exist, whether such differences are associated with differences in presurgical physical function (PF) has not been thoroughly investigated.

OBJECTIVE

To examine trajectories of PF by race/ethnicity before and after TKA among older women.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted among the prospective Women's Health Initiative with linked Medicare claims data. A total of 10 325 community-dwelling women throughout the United States with Medicare fee-for-service underwent primary TKA between October 1, 1993, and December 31, 2014, and were followed up through March 31, 2017.

EXPOSURES

Race/ethnicity comparisons between Hispanic or Latina women, non-Hispanic black or African American women, and non-Hispanic white women (hereafter referred to as Hispanic, black, and white women, respectively).

MAIN OUTCOMES AND MEASURES

Physical functioning scale scores and self-reported activity limitations with walking 1 block, walking several blocks, and climbing 1 flight of stairs were measured by the RAND 36-Item Health Survey during the decade before and after TKA, with a median of 9 PF measurements collected per participant over time.

RESULTS

In total, 9528 white women (mean [SD] age at surgery, 74.6 [5.5] years), 622 black women (mean [SD] age at surgery, 73.1 [5.3] years), and 175 Hispanic women (mean [SD] age at surgery, 73.1 [5.2] years) underwent TKA. During the decade prior to TKA, black women had lower PF scores than white women (mean difference, -5.8 [95% CI, -8.0 to -3.6]) and higher odds of experiencing difficulty walking a single block (5 years before TKA: odds ratio, 1.86 [95% CI, 1.57-2.21]), walking multiple blocks (odds ratio, 2.14 [95% CI, 1.83-2.50]), and climbing 1 flight of stairs (odds ratio, 1.81 [95% CI, 1.55-2.12]). After TKA, black women continued to have lower PF scores throughout the decade (mean difference 1 year after TKA, -7.8 [95% CI, -10.8 to -4.9]). After adjusting for preoperative PF scores, PF scores after TKA were attenuated (mean difference 1 year after TKA, -3.0 [95% CI, -5.3 to -0.7]), with no statistically significant differences in long-term follow-up. Hispanic women had similar PF scores to white women during the pre-TKA and post-TKA periods.

CONCLUSIONS AND RELEVANCE

This study suggests that black women had significantly poorer PF than white women during the decades before and after TKA. Poorer PF after surgery was associated with poorer preoperative PF. Reducing disparities in post-TKA functional outcomes should target maintenance of function preoperatively in the early stages of arthritic disease and/or reduction of delays to receiving TKA once need arises.