Outpatient total knee arthroplasty: A meta-analysis

Introduction: Outpatient total knee arthroplasty (TKA) is attracting growing interest. This meta-analysis compared patient reported outcome measures (PROMs), infection, readmission, re-vision, deep vein thrombosis (DVT), and mortality rates of outpatient versus inpatient TKA. Meth-ods: This meta-analysis was conducted according to the 2020 PRISMA statement. In August 2021, the following databases were accessed: Pubmed, Web of Science, Google Scholar, Embase. All the clinical trials comparing outpatient versus inpatient (>2 days) TKA were considered. Studies which reported data on revision settings were not considered, nor studies which included patients dis-charged between one and two days. Results: Data from 159,219 TKAs were retrieved. The mean follow-up was 5.8 ± 7.6 months. The mean age was 63.7 ± 5.0 years and the mean BMI 30.3 ± 1.8 kg/m2. Comparability was found in age (p = 0.4), BMI (p = 0.3), and gender (p = 0.4). The outpatient group evidenced a greater Oxford knee score (p = 0.01). The inpatient group demonstrated a greater rate of revision (p = 0.03), mortality (p = 0.003), and DVT (p = 0.005). No difference was found in the rate of readmission (p = 0.3) and infection (p = 0.4). Conclusions: With regards to the endpoints evaluated in this meta-analysis, current evidence does not support outpatient TKA. However, given the limited data available for inclusion and the overall poor quality of the included articles, no reli-able conclusion can be inferred. Further high quality clinical trials with clear eligibility criteria are required.