Optimal Timing for Advanced Imaging in Childhood Bone and Joint Infection

Advanced imaging in the management of childhood bone and joint infection (BJI) has the potential to improve disease outcomes. Knowledge about the optimal timing for magnetic resonance imaging (MRI) in relation to both surgically and nonsurgically managed BJI is limited. This study examines the impact of MRI timing on number of surgeries, length of stay (LOS), hospitalization cost, and disease recurrence in childhood BJI.

This is a retrospective review of patients younger than 16 years with acute hematogenous osteomyelitis (AHO) or septic arthritis (SA) treated in the Auckland region from 2018 to 2023. Cases undergoing MRI as part of diagnostic workup were included. Treatment, hours between admission and MRI, LOS, hospitalization cost, and infection recurrence were assessed.

There were 563 cases of BJI, of which 390 met the inclusion criteria. Cases were primarily AHO (85%). The percentage of cases having MRI increased over time from 54% (2018) to 80% (2023). Locally disseminated infections such as subperiosteal abscess or adjacent septic arthritis occurred in 48%. Children with preoperative (n = 145) versus postoperative MRI (n = 60) had a lower reoperation rate (33% vs 77%, P = 0.001) and shorter LOS (14.1 vs 22.4 d, P = 0.002). Hospitalization costs appeared lower but did not differ statistically ($59,419 vs $159,353, P = 0.12). In nonoperative cases, LOS was shorter if an MRI occurred within 48 hours of admission (7.3 vs 10 d, P = 0.03). Disease recurrence was not associated with MRI timing.

Overall, children with BJI who underwent MRI scans before surgery had lower reoperation rates. Children receiving MRIs within 48 hours of admission had shorter LOS.