Clinical question: What risk factors predict septic arthritis surgical debridement failure?
Background: Standard treatment of septic arthritis is debridement and antibiotics. Unfortunately, 23%-48% of patients fail single debridement. Data is limited on what factors correlate with treatment failure.
Study design: Retrospective, logistic regression analysis.
Setting: Billing database query of one academic medical center from 2000-2011.
Synopsis: After excluding patients with orthopedic comorbidities, multivariate logistic regression was performed on 128 patients greater than 18 years of age and treated operatively for septic arthritis, 38% of whom had failed a single debridement. Five significant independent clinical variables were identified as predictors for failure of a single surgical debridement:
- History of inflammatory arthropathy (OR, 7.3; 95% CI, 2.4 to 22.6; P<0.001);
- Involvement of a large joint (knee, shoulder, or hip; OR 7.0; 95% CI, 1.2-37.5; P=0.02);
- Synovial fluid nucleated cell count >85.0 x 109 cells/L (OR, 4.7; 95% CI, 1.8-17.7; P=0.002);
- S. aureus as an isolate (OR, 4.6; 95% CI, 1.8 to 11.9; P=0.002); and
- History of diabetes (OR, 2.6; 95% CI, 1.1 to 6.2; P=0.04).
Using these variables, a prognostic model was created with an ROC curve of 0.79.
The study’s limitations include its retrospective nature, reliance on coding and documentation, small sample size, and the fact that all patients were treated at a single center.
Bottom line: Risk factors for failing single debridement in septic arthritis include inflammatory arthropathy, large joint involvement, more than 85.0 x 109 nucleated cells, S. aureus infection, and history of diabetes.
Citation: Hunter JG, Gross JM, Dahl JD, Amsdell SL, Gorczyca JT. Risk factors for failure of a single surgical debridement in adults with acute septic arthritis. J Bone Joint Surg Am. 2015;97(7):558-564.