Perimarticular fracture bone defect is a common and complicated clinical disease. The current treatment for this type of injury is anatomical reduction of the fracture, where the bone defect is filled with artificial, autologous or allogeneic bone in granular form, and then fixed with plates and screws. However, these bone filler materials exist in a loose accumulation state and cannot form an effective overall support force for the joint. The applicant realized three dimensional (3D) printing of WE43 magnesium alloy with personalized design and porous overall structure, and developed high-temperature heat treatment technology to slow its degradation, which effectively realized the dual stability of degradation rate of magnesium alloy support body and overall structure during the bone repair period. This project will optimize the design of 3D printed WE43 magnesium alloy full-structure in-bone support, and establish a metamaterial pore structure design platform that regulates the physical properties and degradation behavior of porous implants. Fracture from proximal humerus, distal radius and tibial plateau

Inclusion Criteria:

1. Patients with traumatic periarticular fractures of extremities with bone defects requiring bone grafting mainly include distal radius fractures, proximal humerus fractures, and tibial plateau fractures.
2. Between the ages of 18 and 70.
3. Sign informed consent, voluntarily participate in the study, and complete postoperative follow-up.
4. There are no obvious surgical contraindications and no contraindications for magnesium alloy prosthesis implantation.

Exclusion Criteria:

• Patients with pathological fracture ② pregnant women ③ doctors evaluated other conditions that were not suitable for inclusion