Traditionally, children’s long bone fractures have been treated with either manipulation and plaster fixation or traction and plaster fixation. In the last 20 years, with the recognition of the advantages of other fixation methods, especially in terms of reducing the duration of fracture treatment, pediatric orthopedic surgeons have increasingly started to use surgical and various instrumentation methods of fixation. External braces, various splinting plates, and intramedullary pin fixation have all been reported. However, all of these treatments can have complications such as abnormal bone growth after treatment, pin infection, and re-fracture after removal of the external fixation. Dr. Nancy in France was the first to report the use of flexible intramedullary pin cross fixation for femur fractures in children, and this method quickly gained popularity in Europe. It has also become a common treatment method in the United States after being piloted in several large pediatric medical centers since 1997. In recent years, flexible intramedullary nailing has also been widely used in China for long bone fractures of the extremities in children. The principle of fixing the long tuberosity with an elastic intramedullary pin is to restore the fracture alignment by using a pre-bent intramedullary pin to act as a three-point repositioning splint in the medullary cavity, and a small incision is made at the proximal or distal end of the child’s long bone, 1-50 px away from the epiphysis, and two elastic intramedullary pins are inserted obliquely from the side and extended along the child’s bone, passing over the fracture line to the opposite side and cross-fixing the fracture end. After the child’s bone has grown and healed, it can be easily removed through an outpatient procedure. This novel titanium intramedullary pin with an elbow is well integrated into the requirements of minimally invasive and avoiding damage to the child’s epiphysis, helping to reset and fix the fracture without interfering with the blood supply to the fracture end and without damaging the epiphyseal plate. At the same time, the application of the principle of elastic fixation eliminates the stress masking effect and facilitates early activity and functional recovery. It has the advantages of easy operation, little injury, good repositioning, fast recovery, small scar, easy early rehabilitation and few complications. It is a minimally invasive, safe, simple and fast treatment method especially for children and adolescents with long bone fractures, multisegmental fractures and compound injuries.