EXTENDING AN ADULT CLASSIFICATION TO CHILDREN: VALIDATION OF THE BACH SYSTEM FOR PAEDIATRIC OSTEOMYELITIS

INTRODUCTION & AIM: 

There is no widely validated or universally adopted classification system for paediatric osteomyelitis (PO). BACH classification strong predictive performance in adults. This study aimed to assess if BACH can stratify disease severity and predict clinically relevant outcomes in PO.

METHODS:

Retrospective cohort study : 92 children with PO. Classified using the BACH system and stratified into: Uncomplicated, Complex and Limited Options.  Outcomes included surgical burden (need for ≥2 procedures), length of hospital stay, recurrence, and severe complications (amputation, sepsis, severe functional limitation).

RESULTS:

BACH demonstrated a gradient of severity across all outcomes. Children in the limited options group required significantly more procedures (median 3 vs 1 in uncomplicated cases; p<0.001) and had longer hospital stays (48 vs 14 days; p<0.001). The probability of requiring multiple surgeries increased markedly across categories (12.9% vs 60.0% vs 81.3%; p<0.001). Recurrence rates followed the same pattern (3.2% vs 26.7% vs 31.3%; p=0.008).

CONCLUSIONS:

BACH has a strong predictive performance in PO

Effectively stratifies disease severity and anticipates treatment burden

This study supports its use as a unified classification with potential value for clinical decision-making and research standardisation