Comparison Between Septic Arthritis Alone and Coexisting with Other Bone and Joint Infections in Pediatric Patients: A Retrospective Review.

Background: It is unclear whether coexisting septic arthritis and osteomyelitis (CSAO) differs from septic arthritis (SA) alone in terms of susceptible age groups, clinical and paraclinical presentations, and prevalence. This study aimed to compare patients with isolated SA with those presenting with CSAO, determine the efficacy of different parameters used to distinguish those diagnoses, and investigate the prevalence of CSAO due to Methods: The study retrospectively included all patients treated for SA over a 17-year period at Geneva University Hospitals. Clinical, biological, and bacteriological data were analyzed. Magnetic resonance imaging (MRI) was reviewed for all patients to identify those with coexisting osteomyelitis. Comparisons between patients with isolated SA and those with CSAO were performed using the unpaired Mann-Whitney Results: Of 247 patients with osteoarticular infections, 177 with SA fulfilled our inclusion criteria. Of these, 124 had SA alone, and 53 (29.9%) had a CSAO. There were no statistically significant differences between the 2 groups regarding sex, age, and clinical and paraclinical results. When coexisting osteomyelitis was present, 51% of cases were acute and 49% were subacute. Bone infection was found in the metaphyses of 21 patients (39.6%), the epiphyses of 11 (20.8%), and was transphyseal in 10 (18.9%). Whatever the infection location, Conclusions: This study showed that CSAO is common in children, especially among those younger than 4 years, with an unexpectedly high prevalence of subacute osteomyelitis. This should encourage caregivers to use MRI more extensively in diagnostic processes. Clinical and paraclinical data did not contribute to differentiate CSAO from SA. The widespread presence of Level of Evidence: Level III. See Instructions for Authors for a complete description of levels of evidence.