Entrapped periosteum preventing reduction of a Salter-Harris II distal tibial fracture in an adolescent patient. MRI and intra-operative findings

P hyseal or growth plate injuries comprise 18% of all pediatric fractures, with Salter Harris type II as the most common type of fracture injury pattern observed in 61% of patients. The incidence of growth arrest is just over 1%, and the incidence of serious complications is less than 1%. Irreducible physeal fractures, caused by entrapment of the periosteum, tendons or ligaments, are of particular concern because of the potential interference with physeal growth that may lead to early closure. Previously published case reports have described reduction blockage from entrapment of the medial collateral ligament (MCL), the periosteum within the proximal tibial physis, and interposition of the posterior tibial tendon within the distal tibial physis. However, the literature lacks reports of both the MRI findings and intra-operative images of entrapped periosteum, preventing the reduction of a Salter Harris II fracture of the distal tibia. We present an adolescent boy with a Salter Harris II fracture of the distal tibia and entrapment of the periosteum within the physis diagnosed using MRI after failed closed reduction that required surgical excision. The diagnosis and management along with both the MRI and intra-operative findings are discussed. The patient and family were notified that the case would be published and consent was provided.