Risk of Postoperative Infection in Total Knee Arthroplasty Patients with Preoperative Methicillin-Resistant Staphylococcus aureus (MRSA) Colonization

Background/Objectives: While methicillin-resistant Staphylococcus aureus (MRSA) colonization is a known risk factor for surgical site infections, no definitive recommendations exist regarding preoperative S. aureus screening and decolonization protocols due to inconclusive evidence in Orthopedic Surgery. This study aimed to examine the correlation between preoperative MRSA colonization and postoperative infections in Total Knee Arthroplasty (TKA) patients. Methods: Data from 2005 to 2023 were collected from TriNetX, a global health research network, reviewing 237,360 unique patients. TKA patients were assigned under Current Procedural Terminology, while International Statistical Classification of Diseases Codes were used to identify preoperative comorbidities and postoperative complications. Demographic and analytical statistics were compared between MRSA-positive and control groups before and after propensity matching. Results: The MRSA-positive group had a significantly (p < 0.001) higher proportion of patients over 65 years (47.17% vs. 38.46%), obesity (41.76% vs. 34.67%), smoking disorders (33.36% vs. 19.73%), and diabetes (25.06% vs. 19.85%) compared to the control group. Postoperative complications were significantly (p < 0.001) more frequent in the MRSA-positive group, specifically periprosthetic joint infection (PJI) (4.11% vs. 0.79%, OR = 5.40), deep (0.12% vs. 0.01%, OR = 11.15) and superficial (0.37% vs. 0.09%, OR = 4.17) surgical site infections, and wound dehiscence (1.11% vs. 0.52%, OR = 2.13). The matched analysis confirmed significantly (p < 0.001) higher rates of PJI (4.39% vs. 1.18%, OR = 3.59). Conclusions: Our results illustrated preoperative colonization of MRSA as associated with an increased risk of wound-related complications. Surgeons and patients must consider preoperative MRSA colonization status when deciding if TKA is an optimal treatment option.