Knee PainIn the workup of monoarticular arthritis, the question that emergency physicians constantly struggle over is whether the patient has a nongonococcal septic arthritis. This joint infection alarmingly damages and erodes cartilage within only a few days.

This installment of the Paucis Verbis (In a Few Words) e-card series reviews the JAMA Rational Clinical Examination article which asks “Does this patient have septic arthritis?” Pooled sensitivities and likelihood ratios were calculated. These statistics are always helpful when trying to figure out the patients probability of having a septic joint.

I was surprised to learn that only about 50% of patients with septic joints have a fever. Note that a hip or knee prosthesis PLUS an overlying skin infection pretty much equals a septic joint (LR = 15.0).

Risk factors are listed in the table with the corresponding sensitivities, specificities, and likelihood ratios.

PV Card: Septic Arthritis


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Michelle Lin, MD
ALiEM Founder and CEO
Professor and Digital Innovation Lab Director
Department of Emergency Medicine
University of California, San Francisco
Michelle Lin, MD

@M_Lin

Professor of Emerg Med at UCSF-Zuckerberg San Francisco General. Founder of ALiEM @aliemteam #PostitPearls https://t.co/7v7cgJqNEn
Michelle Lin, MD