Associations with unplanned repeat irrigation and debridement of native septic arthritis.

PURPOSE: To identify associations with unplanned repeat irrigation and debridement (I&D) after arthrotomy for native septic arthritis.

METHODS: A retrospective review identified patients with native septic arthritis treated with open arthrotomies. The primary outcome was unplanned repeat I&D within 90 days. Associations evaluated for included comorbidities, ability to bear weight, fever, immunosuppressed status, purulence, C-reactive protein, erythrocyte sedimentation rate, white blood cell count (synovial fluid and serum levels), and synovial fluid polymorphonuclear cell percentage (PMN%).

RESULTS: There were 59 arthrotomies in 53 patients involving the knee (n = 32), shoulder (n = 10), elbow (n = 8), ankle (n = 6), and hip (n = 3). The median patient age was 52, and a 71.2% were male. An unplanned repeat I&D was required in 40.7% (n = 24). The median time to the second I&D was 4 days (interquartile range 3 to 9). On univariate analysis, unplanned repeat I&Ds were associated with fever (p = 0.03), purulence (p = 0.01), bacteria growth on cultures (p = 0.02), and the use of deep drains (p = 0.05). On multivariate analysis, the only variables that remained associated with unplanned repeat I&Ds were fever (odds ratio (OR) 5.5, 95% confidence interval (CI) 1.3, 23.6, p = 0.02) and purulence (OR 5.3, CI 1.1, 24.4, p = 0.03).

CONCLUSIONS: An unplanned repeat I&D was required in 40.7% of patients and was associated with fever and purulence. These findings highlight the difficulty of controlling these infections and support the need for future research into better methods of management.

LEVEL OF EVIDENCE: Diagnostic, Level III.