Core Viewpoint - The passing of Academician Gu Yudong, a pioneer in hand surgery and limb reconstruction, marks a significant loss for the medical community, particularly in the field of upper limb functional reconstruction and brain science research [1][3][4]. Group 1: Contributions to the Field - Under Gu Yudong's leadership, Huashan Hospital's hand surgery department evolved from traditional hand trauma treatment to upper limb functional reconstruction, and eventually to limb reconstruction and brain science [1][4]. - Gu Yudong was instrumental in establishing hand surgery as an independent specialty in China, with Huashan Hospital being the first to do so in 1961 [3]. - He pioneered the "dual blood supply system" method, achieving a 100% success rate in toe-to-thumb transplantation, which earned him the National Science and Technology Progress Second Prize [4]. Group 2: Recognition and Awards - In 2023, the project led by Professor Xu Wendong and Academician Gu Yudong, focusing on repairing limb movement disorders through peripheral-central pathway breakthroughs, won the National Science and Technology Progress First Prize [4]. - Gu Yudong held several prestigious positions, including Director of the National Clinical Research Center for Geriatric Diseases and Editor-in-Chief of the Chinese Journal of Hand Surgery [3]. Group 3: Personal Impact and Legacy - Gu Yudong's sudden passing on May 24, 2023, was met with deep sorrow from colleagues and students, highlighting his dedication as he continued to work until his last moments [3][4]. - His vision for the future of hand surgery included the restoration and reconstruction of intrinsic muscle function, which he regarded as a significant challenge in the field [4].