Septic arthritis is a medical emergency that may be associated with significant mortality (10-15%) and morbidity (25-50%), in case of delayed management. When septic arthritis is suspected, arthrocentesis and culture of the synovial fluid are the gold standard. The absence of fever, rigors, leukocytosis or elevated erythrocyte sedimentation rate does not exclude the diagnosis of septic arthritis. Age, chronic arthropathy, or arthroplasty are particularly associated with increased morbidity. Therapy consists in antibiotics, joint immobilisation (maximum 3 days) and medical drainage, in case of persisting joint effusion.