Objectives: The leading cause of total joint arthroplasty (TJA) readmission is wound complications with national average readmission rate of 5.3%, and mean cost of $27,979 per hospital stay. The study aimed to evaluate the impact of eCAP, a warranty system for using Smith+Nephew’s Primary Total Hip or Knee System with Oxinium + Single Use Negative Pressure Wound Therapy + Antimicrobial Silver Dressing together in 44 hospital facilities who have implemented it, compared to non-eCAP facilities for readmissions in patients undergoing primary TJA surgery.

Methods: We retrospectively reviewed data from the Limited Data Set version of the Medicare Standard Analytic File– 100% sample. The inpatient and Denominator files were used, and claims were linked based on the unique beneficiary identifier to track beneficiaries longitudinally. 1:1 Propensity Score Matching was used to control for age, Charlson Comorbidity Index, and gender. All cause and infection-related readmission over 30, 90 and 180 days for patients who had at least one year follow up data before 30 June 2021 were computed.

Results: We matched 2,401 eCAP and 2,401 non-eCAP patients. Patients on the eCAP program were 22% less likely to be readmitted (all cause) than non-eCAP patients (odds ratio [OR] 0.78 (0.58-1.04) p=0.09, 18% OR 0.82 (0.66-1.02) p=0.07, 18% OR 0.82 (0.7-0.96) p=0.02), over 30, 90 and 180 days respectively. A bigger effect was observed for infection-related readmissions, where eCAP patients were 45% less likely to be readmitted (OR, 0.55 (0.3-1) p=0.05, 47% OR 0.53 (0.34-0.85) p=0.008, 45% OR 0.55 (0.37-0.82) p=0.004), over 30, 90 and 180 days respectively compared to non-eCAP patients.

Conclusions: Hospital systems that adopted the eCAP program observed significantly reduced readmissions, in particular infection-related readmission in TJA patients in this study. Additional data is needed to assess if this translates to reductions in revisions and therefore cost overall.