Title : Sensitivity and specifity of Magnetic Resonance Imaging (MRI) in Acute Musculoskeletal (MSK) infections in paediatric population: A single-centre experience
Abstract:
Introduction: Uncomplicated osteomyelitis/Musculoskeletal (MSK) infection in children usually responds very well to antibiotic therapy and less than 5% progress on to develop chronic infection. The British Orthopaedic Association Standards for Trauma (BOASt) advise Magnetic Resonance Imaging (MRI) as the second line modality in paediatric patients with suspected MSK infection. This study evaluates the adherence to national pathways, specifity and sensitivity of MRI in early identification of paediatric MSK infections.
Methodology: This retrospective audit was performed in accordance with STROBE guidelines. Skeletally immature patients (based on age less than 18) who were admitted consecutively at a single-centre over a period of one year with the probable diagnosis of MSK infection and further subjected to MRI scan were taken into the study. Investigations carried out on subjects were compared to set BOASt criteria. Basic statistical analysis was carried out using Microsoft Excel (v13).
Results: Fifty-seven (n=57) patients were identified from our database, with 56% (n=32) being male. All patients (100%) had appropriate management for suspected joint infection as per BOAST standards. Of those, 79% (n=45) required MRI scan. The mean age of presentation was 6.3 years. 40% of patients (n=18) had positive MRI finding suggestive of a focus of MSK infection, of which 26% (n=12) had the MRI within 48 hours and 13% after 48 hours (n=6). 88% (n=16) were found to have septic arthritis (n=9) or osteomyelitis (n=7), whilst 11% (n=2) had non-infectious causes. 60% of patients (n=27) where MRI scan was negative for infection, 42% (n=19) had their MRI scan with 48 hours and in 17% (n=8) patients it was delayed for more than 48 hours. 31% of patients (n=14) had at least one dose of antibiotic prior to MRI. Sensitivity and specificity of MRI was calculated as 88% and 100%, respectively.
Conclusion: MRI is highly sensitive and specific for paediatric MSK infections. Service development should aim to prioritise MRI availability, accessibility and reporting for children presenting with suspected MSK.
