1, the typing of periprosthetic fractures of the femur after total hip arthroplasty: The diagnosis is generally determined by five factors: the fracture site, the integrity of the prosthesis and fracture, the quality of the backbone, the physiological condition and age of the patient, and the experience of the physician. There are several methods of staging periprosthetic fractures, some of which provide only a picture of the fracture site and have little significance for treatment. The most important factor affecting treatment is the stability of the femoral prosthesis. a very helpful Vancouver staging method was provided by Duncan et al. The Vancouver staging method combines three important factors: fracture site, prosthetic stability, and quality of the surrounding diaphysis. Based on the fracture site, it is classified as type A (rotor area fracture), type B (fracture around the stem or head of the femoral prosthesis), and type C (fracture below the femoral stem). Treatment does not rely on in situ arthroplasty, and types A and B are subdivided into subtypes in combination with the stability of the prosthesis. Type A: divided into large and small rotor fractures (AG, AL). If the fracture fragment is too large and the middle part is missing, it will lead to prosthetic instability. type B: it is further divided into three subtypes according to the stability of the prosthesis and the condition of the femur (type B1, the fracture prosthesis is firmly fixed; type B2, the fracture femur is of fair quality and the prosthesis appears loose; type B3, the fracture has severe bone loss such as osteolysis or comminution, complicated by prosthetic loosening). type C: the fracture of the distal end of the prosthesis, which can be treated separately. 2, treatment: most of the type A fractures can be bed/braking and close observation, if the fracture is due to severe osteolysis, revision surgery should be performed, if necessary, the acetabular prosthesis can be revised at the same time B1 non-operative complications are more, and loosening, fracture does not heal and deformity healing incidence is higher, more incision and internal fixation treatment, more use of titanium cable or screws, allograft bone plate and plate. B2 and B3 type need to replace the prosthesis Type B2 and B3 require replacement of the prosthesis. Type C fractures require incision and internal fixation. If the prosthesis is loose, the fracture can be treated with incision and internal fixation first, and then revision surgery can be performed after the fracture has healed.