Increased 30-Day Readmission Rates in Total Knee Arthroplasty Patients Using Hypoallergenic Implants

Metal hypersensitivity has emerged as a notable concern in the context of total knee arthroplasty (TKA), leading to the development of hypoallergenic implants. Current studies assessing hypoallergenic TKA implants suggest a decrease in quality of life and patient-reported outcome measures when compared with TKA with standard implants. This study seeks to compare clinical outcomes, including readmission and medical complications between patients undergoing TKA with hypoallergenic versus standard implants.

A retrospective review of our institution's prospective Mayo Clinic Joint Replacement Database was conducted to identify all patients aged 18 years and older who underwent unilateral TKA between January 2019 and August 2022 using either hypoallergenic or standard implants. Cohorts were compared based on factors, such as age, heart disease, diabetes, alcohol use, smoking history, BMI, allergies, and ASA classification. Clinical outcomes included 30-day readmission, ED visits within 30 days, and medical complications. Statistical analysis was done using multiple logistic regression, chi-square, and paired t-tests.

6954 TKAs (6626 standard and 320 hypoallergenic) were identified through retrospective review. Hypoallergenic implant patients were associated with higher 30-readmission (2.19% vs. 0.74%, P < 0.001, 95% confidence interval, 1.052 to 1.132). No notable association was found between hypoallergenic TKA and BMI, ASA, heart disease, diabetes, alcohol, smoking incidence, or medical complications (all P > 0.05).

There is a notable difference in 30-day readmission rates between patients undergoing TKA with hypoallergenic implants and those with standard implants, underscoring the need for heightened vigilance in this patient population.