Obesity, Anemia, and Chronic Obstructive Pulmonary Disease Identified as Key Risk Factors of Superficial Wound Washouts After Total Joint Arthroplasty.

Superficial surgical site infections (SSIs) limited to the skin and subcutaneous tissue following total joint arthroplasty (TJA) remain a significant source of patient morbidity, often necessitating surgical irrigation and debridement (I&D). While risk factors for deep infections such as periprosthetic joint infections are well studied, predictors of superficial SSIs managed with I&D remain underexplored. A retrospective cohort analysis was performed using the PearlDiver Mariner10 capturing over 161 million patients across inpatient and outpatient settings in the United States. Patients undergoing primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) between 2010 and 2022 were identified and stratified by the occurrence of subsequent wound I&D. Patients who underwent prosthetic revision were excluded to isolate superficial infections. A total of 54,868 THA and 103,235 TKA patients were identified, with 405 (0.738%) and 568 (0.549%) requiring I&D, respectively. Among THA patients, significant predictors of superficial SSI requiring I&D included obesity (odds ratio [OR]: 1.91, p < 0.001), hypothyroidism (OR: 1.45, p = 0.005), anemia (OR: 1.64, p < 0.001), Type II diabetes mellitus (OR: 1.70, p < 0.001), and chronic obstructive pulmonary disease (COPD) (OR: 1.51, p = 0.004). In the TKA cohort, significant predictors included obesity (OR: 1.40, p = 0.002), anemia (OR: 2.21, p < 0.001), malnutrition (OR: 2.18, p < 0.001), Type II diabetes mellitus (OR: 1.43, p = 0.001), tobacco use (OR: 1.45, p = 0.005), and COPD (OR: 2.02, p < 0.001). The findings emphasize the importance of targeted preoperative optimization in patients with risk factors such as obesity, anemia, malnutrition, diabetes, and COPD. Differential predictors between TKA and THA highlight the need for joint-specific perioperative strategies.