The Impact of Social Determinants of Health on Outcomes and Complications After Total Knee Arthroplasty

Abstract

Background: Social determinants of health (SDOH) are important factors in the delivery of orthopaedic care. The purpose of this study was to investigate the relationship between outcomes following total knee arthroplasty (TKA) and both the Social Vulnerability Index (SVI) and the Area Deprivation Index (ADI). Methods: The Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) database was utilized to identify TKA cases for inclusion. Demographic characteristics and medical history were documented. The SVI, its subthemes, and the ADI were analyzed. Outcome data included length of stay, discharge disposition, postoperative change in the Knee Injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS, JR), 90-day incidences of emergency department (ED) visits, readmission, death, deep venous thrombosis (DVT) and/or pulmonary embolism (PE), periprosthetic fracture, implant failure, periprosthetic joint infection (PJI), and all-cause reoperation. Database cross-referencing was completed to document aseptic and septic revisions beyond 90 days postoperatively. Bivariate quartile-stratified and multivariable analyses were used to associate deprivation metrics with outcomes. Results: A total of 19,321 TKA cases met inclusion criteria. Baseline patient characteristics varied among the SVI and/or ADI quartiles, with patients of non-White race and with a greater number of comorbidities noted in higher deprivation quartiles. Higher SVI and/or ADI quartiles were correlated with an increased rate of discharge to a skilled nursing facility (p < 0.05). A higher SVI and/or ADI quartile was associated with increased incidences of ED visits and readmissions postoperatively (p < 0.05). DVT and/or PE and long-term aseptic revision were the complications most strongly associated with higher deprivation metrics. Upon multivariable analysis, greater length of stay and greater incidences of ED visits, readmissions, DVT and/or PE, and aseptic revision remained significantly associated with greater deprivation based on multiple metrics. Conclusions: Greater deprivation based on multiple SVI subthemes, the composite SVI, and the ADI was significantly associated with increased length of stay, non-home discharge ED visits, and readmissions. The SVI and the ADI may be important considerations in the perioperative assessment of patients who undergo TKA. Level of Evidence: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.