The incidence of physeal fractures in the lower limb and the frequency of premature physeal closure: a cohort study of 236 patients

Abstract

Background and purpose: Physeal fractures represent 15–20% of all pediatric fractures and may lead to premature physeal closure (PPC). The aim of our study was to determine the incidence rates of physeal fractures in the lower limb and the proportion of PPC that lead to limb length discrepancy (LLD), and/or angular deformity (AD).Patients and methods: This retrospective study included 236 consecutive children with physeal fracture in the tibia, distal femur, or distal fibula. We estimated incidence rates and reviewed medical records and radiographs to obtain information regarding the development of PPC leading to LLD and AD. Of the 236 children, 100 had planned growth control or were referred for growth control due to symptoms of PPC.Results: The total incidence rate was 35 (95% CI 30–39) per 100,000 person-years, with 1.2 (CI 0.5–23) for distal femur, 5.7 (CI 3.1–7.8) for proximal tibia, 14 (CI 11–17) for distal tibia, and 14 (CI 11–17) for distal fibula. The overall prevalence of PPC was 9.7% (CI 6.3–14), while the prevalence was 38% (CI 8.5–76) for distal femur, 15% (CI 5.9–31) for proximal tibia, 14% (CI 7.4-–22) for distal tibia, and 1.1% (CI 0.3-–59) for distal fibula. We found a significant higher hazard of PPC in fractures with ≥ 3 mm displacement (hazard ratio: 12, CI 1.5–97).Conclusion: 10% of children with physeal fractures developed PPC that led to LLD or AD. The highest hazard ratio was in children who had an initial fracture displacement. This study highlights the importance of routine and uniform growth evaluation after a physeal fracture