We searched our electronic database for children (<18 years old) admitted to the Emergency Room of our tertiary center from January 2020 to March 2024 with acute skeletal pain without any referred traumatic injury, who underwent an MR within seven days.

Requests with at least one of the following hypotheses “infection”, inflammation”, “tumor” according to clinical assessment and eventually to the findings of first level examinations (US and/or X-ray) were included. For each patient, demographics, affected skeletal area, clinical symptoms (e.g.,fever, pain), comorbidities, laboratory findings (e.g., high C-reactive protein levels) at admission were collected. The accuracy of the requests was assessed using as reference the diagnosis achieved by MR imaging. Logistic regression analysis was used to evaluate if the proposed model was suggestive of osteomyelitis. For all the analyses we used the software SPSS (v.28, IBM Armonk, NY, USA) applying p<0.05 as significance level.