LAUSR

Objectives: To investigate the fracture pattern and periosteal entrapment in adolescent distal tibial physeal fractures. Design: Retrospective case series. Setting: Level I academic trauma center. Patients/Participants: Fifty patients (10–16 years of age) with displaced Salter–Harris type II, III, or IV distal tibial physeal fractures were retrospectively reviewed. Intervention: Periosteal involvement, fracture pattern. Main Outcome Measurements: We investigated the incidence and location of periosteal entrapment in those fractures and the angle of the fracture plane of metaphyseal fragments on axial plane by using magnetic resonance imaging. Results: Of the 15 type II, 12 type III (4 malleolar and 8 Tillaux), and 23 type IV (2 malleolar and 21 triplane) fractures, 72.0% (36/50) presented with periosteal entrapment. Among all type II and triplane fractures, periosteal entrapment was observed in the anterolateral corner when there was any displacement on that corner. By contrast, only 1 of 8 Tillaux fractures presented with periosteal entrapment. In almost all supinated foot injuries of type II and triplane fractures, the metaphyseal fracture line was parallel to the intermalleolar axis on axial plane. Conclusions: Salter–Harris type II and triplane fractures have a high risk of periosteal entrapment especially in the anterolateral corner. Therefore, even without preoperative magnetic resonance imaging, surgical repositioning of entrapped periosteum should be considered after failed closed reduction. In cases of supinated foot injuries of type II or triplane fractures requiring surgical fixation, a metaphyseal fracture plane parallel to the oblique coronal plane connecting the medial and lateral malleoli may assist surgeons in achieving appropriate metaphyseal fixation. Level of Evidence: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.