Brachial plexus lesions in newborns were first described in the publications by Duchenne (1872) and Erb (1874). Various factors are involved in their etiopathogenesis and different levels of severity can be detected in these injuries. It is known that the majority of cases recover spontaneously, but a significant percentage will have significant aesthetic and functional sequelae as the child grows. One of the conditions that arises as a result of this injury is supination deformity, which leads to limitations in activities such as dressing, eating or drinking water. Aimed at surgeons and rehabilitation professionals, this book provides an overview of the evolution of this deformity and encourages the reader to think about forms of prevention and treatment. We hope that this book will help to enrich your knowledge and serve as a guide for treating patients.