Original research| Volume 101, ISSUE 9, P1509-1514, September 2020

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Predictors of Discharge Settings After Total Knee Arthroplasty in Medicare Patients



      To determine the factors associated with acute hospital discharge to the 3 most common postacute settings following total knee arthroplasty (TKA): inpatient rehabilitation facilities (IRFs), skilled nursing facilities (SNFs), and directly back to the community.


      Retrospective cohort study.


      Acute care hospitals submitting claims to Medicare.


      National cohort (N=1,189,286) of 100% Medicare Part A data files from 2009-2011.


      Not applicable.

      Main Outcome Measures

      Observed rates and adjusted odds of discharge to the 3 main postacute settings based on the clinical and facility level variables: amount of comorbidity, bilateral procedures, and facility TKA volume.


      Using IRF discharge as the reference, patients who received a bilateral procedure had lower odds of both SNF and community discharge, patients with more comorbidity had lower odds for community discharge and higher odds for SNF discharge, and patients who received their TKA from hospitals with lower TKA volumes had lower odds of SNF and community discharge.


      Clinical populations within Medicare beneficiaries may systematically vary across the 3 most common discharge settings following TKA. This information may be helpful for a better understanding on which patient or clinical factors influence postacute care settings following TKA. Additional research including functional status, living situation, and social support systems would be beneficial.


      List of abbreviations:

      ASA (American Society of Anesthesiologists), CCI (Charlson Comorbidity Index), IRF (inpatient rehabilitation facility), LOS (length of stay), MedPAR (Medicare Provider Analysis Review), OR (odds ratio), PAC (postacute care), SNF (skilled nursing facility), TKA (total knee arthroplasty)
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