Superoxide solution irrigation for septic arthritis: a prospective clinical study of efficacy and a widened therapeutic window.

BACKGROUND: Septic arthritis is an orthopedic emergency, with the knee being the most commonly affected joint. Standard irrigation with normal saline does not provide biofilm-disrupting efficacy, a key factor in treatment failure, especially against virulent organisms such as Staphylococcus aureus and Pseudomonas aeruginosa. This study evaluates the use of Hydrocyn, a superoxidized solution with known antibiofilm properties, as an intraoperative joint irrigant. METHODS: A prospective case series was conducted on 17 adults with native knee septic arthritis from 1 February 2024 to 31 December 2024. All patients underwent standard arthrotomy or arthroscopic washout with joint irrigation using Hydrocyn. Primary outcomes included serial measurement of inflammatory markers, including C-reactive protein (CRP) levels and white blood cell count (WBC), as well as knee range of motion (ROM) at baseline, 1, 2, and 6 weeks; ROM was further assessed up to 12 weeks postoperatively. RESULTS: Pathogens were identified in 94.1% of cases, including methicillin-resistant Staphylococcus aureus (MRSA) (17.6%) and P. aeruginosa (11.8%). Significant improvements were observed in CRP levels (p < 0.001), WBC (p = 0.001), and knee ROM (p < 0.001) at 6 weeks. The reoperation rate due to reinfection was 5.8%. Patients undergoing irrigation more than 24 h after admission demonstrated improvements in outcomes equivalent to those treated within 24 h, with no statistical difference between the groups. CONCLUSION: Superoxide solution irrigation, combined with antibiotics, surgical debridement, and physiotherapy, is associated with excellent clinical outcomes, including rapid normalization of inflammatory markers, functional recovery, and a low reoperation rate. Its potent biofilm-disrupting action may mitigate the adverse effects of delayed surgical intervention, challenging current treatment paradigms.