A multi-center study of 563 periprosthetic joint infections (PJIs) found that 16.5 % were culture negative. These patients more often had prior revision or PJI, longer symptom duration and fewer systemic signs. On multivariable analysis, symptom duration >12 weeks was the only independent risk factor (odds ratio 2.24). The findings support the fact that culture-negative infections present insidiously, informing diagnostic strategies.

We found three characteristics associated with increased risk of septic arthritis. Additionally, we found that lowering historic thresholds may be appropriate in order to prevent missed or delayed diagnosis of a pathology with considerable morbidity.