This article reviews acute and chronic lower extremity injuries in children, focusing mainly on those traumas typical of the pediatric population. The child is not just a small version of an adult, so physicians need a very detailed knowledge of the anatomy and physiologic changes occurring during growth to understand and evaluate the mechanism of trauma, and choose the most adequate management. In adolescents the most common lesion encountered affects the physes, which are still open. They predispose to injury as the weakest point in the kinetic chain, so those mechanisms responsible for ligamentous traumas in adults can cause physeal injuries in a skeletally immature patient. In association with them, apophyseal lesions are also very common, leading to avulsion injuries at the site of tendon origin or insertion, also called locus minoris resistentiae. Understanding these types of injuries is essential, specifically for the radiologist, because a missed diagnosis can lead to later complications such as growth arrest and osteoarthritis.