Objective To explore the application of three-dimensional(3D) printing technology in precise and individualized surgical treatment of severe distal humeral bone defect. Methods Five patients with severe distal humeral bone defects were treated with customized 3D printing prostheses between December 2010 and December 2015. There were 4 males and 1 female, with an age of 23-57 years(mean, 35 years); and the length of the bone defect was 5-12 cm(mean, 8 cm). The cause of injury was mechanical injury in 2 cases...