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

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 deter-mine the incidence rates of physeal fractures in the lower limb and the proportion of PPC that lead to limb length dis-crepancy (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 inci-dence rates and reviewed medical records and radiographs to obtain information regarding the development of PPC lead-ing 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 & GE; 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 displace-ment. This study highlights the importance of routine and uniform growth evaluation after a physeal fracture.