Racial Disparities in Total Knee Replacement Failure are not Explained by Poverty

OBJECTIVES:

To determine whether racial disparities in total knee replacement (TKR) failure are explained by poverty.

METHODS:

Black and white New York (NY) State residents enrolled in a prospective single-institution TKR registry 1/1/2008-2/6/2012 who underwent primary unilateral TKR(N=4062) were linked to the NY Statewide Planning and Research Cooperative System database (1/1/2008-12/31/2014) to capture revisions performed at outside institutions. Patients were linked by geocoded addresses to residential census tracts. Multivariable Cox regression was used to assess predictors of TKR revision. Multivariable logistic regression was used to analyze predictors of TKR failure, defined as: 1. TKR revision in NY State ≤2 years after surgery or; 2. HSS TKR Quality of Life score “not improved” or “worsened” 2 years after surgery.

RESULTS:

Mean age was 68.4±10 years, 64% were female, 8% lived in census tracts with >20% under the poverty line, 9% were black. Median follow-up was 5.3years. 3%(122/4062) required revision a median[IQR] 454[215,829] days after surgery. TKR revision risk was higher in blacks than whites, HR 1.69(95%CI 1.01-2.81), but in multivariable analysis, only younger age, male sex and constrained prosthesis were predictors of TKR revision. TKR failure occurred in 200/2832(7%) cases with 2-year surveys. Risk factors for TKR failure were non-osteoarthritis TKR indication, low surgeon volume and low HSS Expectations Survey score, but not black race. Community poverty was not associated with TKR revision or failure.

CONCLUSIONS:

There was a trend towards higher TKR revision risk in blacks, but poverty did not modify the relationship between race and TKR revision or failure.