Written by Caitlin Nicholson
Spoon Feed
In children with non-traumatic limp, existing clinical decision rules for septic arthritis performed poorly, with reduced range of motion emerging as the strongest individual predictor – despite being excluded from current tools.
Nothing soothing about a joint that’s not moving…
This prospective observational study assessed the diagnostic performance of Kocher’s and Caird’s clinical decision rules (CDRs) for septic arthritis among 535 children with acute atraumatic limp in emergency departments. Fourteen cases (2.6%) of septic arthritis were identified. Kocher’s and Caird’s rules yielded AUCs of 0.72 (95%CI 0.42–1.00) and 0.78 (95%CI 0.52–1.00), respectively. The best individual predictor was markedly reduced joint range of motion (LR+ 12.1, 95%CI 7.5–19.5), which is not a component of either decision rule.
How will this change my practice?
Septic arthritis is a rare but critical diagnosis in children with acute non-traumatic limp. Kocher’s and Caird’s underperform in the ED setting – partly due to limited lab testing and omission of key clinical signs, such as reduced joint range of motion and clinical impression of systemic disease. I will continue to suspect septic joint in patients with decreased range of motion, despite a normal laboratory workup.
Source
Test characteristics of clinical findings and clinical decision rules for the diagnosis of septic arthritis in children with an acute limp presenting to the emergency department: a prospective observational study. Emerg Med J. 2025 Apr 8:emermed-2024-214607. doi: 10.1136/emermed-2024-214607. Epub ahead of print. PMID: 40199562
So far this year 2 preteen males unilateral knee swelling with limp not red or warm no rash or fevers both had Lyme