Physeal Bar Formation After Salter-Harris III and IV Medial Malleolus Fractures in Children Aged ≤10 Years

Abstract

INTRODUCTION: Salter-Harris (SH) III and IV medial malleolar fractures in young children pose a risk of physeal bar formation and subsequent growth disturbance. The aim of this study was to compare surgical versus nonsurgical treatment and to identify factors predictive of physeal injury. METHODS: A retrospective cohort analysis examined patients aged ≤10 years treated for SH III/IV medial malleolar fractures between 2012 and 2024 at a single institution. Patients received either surgical (open reduction and internal fixation (ORIF) or percutaneous reduction and screw fixation (PRSF)) or nonsurgical (casting/boot) management and had ≥6 months of radiographic follow-up. Demographic, clinical, and radiographic variables including articular displacement, lateral distal tibial angle (LDTA), and physeal bar formation were compared between treatment groups and subgroups with or without bar formation. RESULTS: Thirty-two patients (16 surgical, 16 nonsurgical) met inclusion criteria. The overall incidence of physeal bar formation did not differ between treatment groups (surgical: 25% vs. nonsurgical: 19%; P = 1.000). Physeal bar formation was significantly associated with greater pre-reduction articular displacement (median: 9.1 mm vs. 2.4 mm; P = 0.045), changes in LDTA (6.2° vs. 1.0°; P = 0.006), and delayed union (57% vs. 4%; P = 0.004). Clinically significant physeal bars occurred exclusively in patients with comminuted fractures (P = 0.007). Final articular displacement was significantly lower after ORIF (0.0 mm vs. 1.0 mm; P = 0.012), although revision surgery for implant removal was more common (P < 0.001). CONCLUSION: The risk of physeal bar formation after SH III and IV medial malleolar fractures was not influenced by surgical versus nonsurgical treatment. Instead, greater initial fracture displacement and comminuted fracture morphology predicted physeal injury.