Secondary Displacement of Forearm Fractures in Children: When to Anticipate Remodeling and When to Intervene?

Background/Objectives: Conservative management of pediatric forearm fractures remains challenging due to the high incidence of secondary displacement. Given the remarkable remodeling potential of children's bones, clinicians must decide whether to rely on natural healing or intervene. This study evaluated whether accepted secondary displacements affect long-term outcomes and sought to identify predictors of functional impairment. Methods: This retrospective cohort study assessed the long-term outcomes of a cohort of 410 consecutive children who presented with 212 distal metaphyseal and 198 diaphyseal both-bone forearm fractures between 2006-2010. In all patients, closed reduction was recommended for ≥50% displacement, ≥15° angulation (<10 years), or ≥10° angulation (10-16 years). Secondary displacements were frequently accepted, anticipating remodeling. We included 316 children (<16 years) with both-bone forearm fractures (147 diaphyseal, 169 distal metaphyseal), representing 77% of the original cohort, for long-term follow-up (mean 7.2 years, minimum 4 years). Functional and radiographic outcomes were compared between accepted secondary displacements and maintained alignments, stratified by fracture location. Multivariate logistic regression identified predictors of long-term functional impairment, defined as ≥15° loss of pro-supination or QuickDASH ≥ 20. Results: In the distal metaphyseal group there were 50 secondary displacements out of 212 fractures, of which 31 were accepted. In the diaphyseal group there were 60 secondary displacements, of which 49 were accepted. At long-term follow-up, patients with accepted secondary displacements had no clinically relevant differences in functional or radiographic outcomes compared with those with maintained alignments across both diaphyseal and distal metaphyseal fracture groups. For distal fractures, complete initial radial displacements, re-fractures, and bicortical ulnar fractures predicted pro-supination loss ≥ 15° or QuickDASH ≥ 20. For diaphyseal fractures, older age at trauma predicted increased risk of pro-supination limitation. Conclusions: Accepted secondary displacements did not worsen long-term outcomes, supporting reconsideration of strict reduction criteria. The substantial remodeling capacity of pediatric bone-especially in distal metaphyseal fractures in skeletally immature children-should be emphasized when making treatment decisions to avoid unnecessary surgical interventions.