Artificial hip replacement is an effective method to treat advanced hip joint diseases, and its surgical technique has become mature and widely used in clinic. If the indications are correctly selected, the surgical technique is standardized, and regular postoperative rehabilitation can achieve satisfactory long-term results. With the increase in the number of artificial hip replacements, there will be more and more cases requiring revision. From the domestic and international literature reports, most of the cases requiring revision are caused by instability and aseptic loosening. These reasons are mostly related to the surgical technique of the initial replacement, so how to do a good case of artificial hip replacement has the following attention problems: Indications for surgery due to any of the following diseases, resulting in hip pain, dysfunction and significantly affect the quality of life: 1, osteoarthritis of the hip joint, 2, necrosis of the femoral head, 3, femoral neck fracture gardenIII, IV, hip joint, 4, ankylosing spondylitis, 5, hip joint, 5, hip joint, 5, hip joint, 5, hip joint, 5, hip joint, 5, hip joint, 5, hip joint, 5, hip joint, 5, hip joint Ankylosing spondylitis 5, RA 6, advanced hip infectious disease 7, DDH 8, severe acetabular fracture 9, proximal femur peri-acetabular tumor Pre-operative plan 1, prosthesis selection: biological, cemented, hybrid three types. Generally, for the first time replacement, those with good bone quality mostly choose biological type prosthesis, and the interface of prosthesis chooses metal-to-polyethylene or ceramic-to-polyethylene as the mainstream. The femoral stem is selected from products with good long-term follow-up results, and in recent years, the fully coated tapered square stem has been increasingly favored by physicians. For advanced age, poor bone condition and revision surgery, cemented or hybrid types are preferred. Modern cementing techniques are recommended when using cemented prostheses. 2, incision selection: each approach has different advantages and disadvantages, depending on the surgeon’s familiarity with the nature and characteristics of the lesion to decide. Currently, the anterolateral (Watson-Jones) and posterolateral (Gibson) approaches are more commonly used. The anterolateral incision is convenient for dealing with the lateral femur, reveals the acetabulum a little bit poorly, and is less dislocated in the postoperative period, but affects the gluteus medius muscle during the operation, and the femur is obviously swollen in the postoperative period. Posterolateral:The acetabulum is well exposed, the gluteus medius muscle is not affected, the postoperative swelling of the femur is light, and the risk of postoperative dislocation is high. At present, domestic and foreign scholars mostly adopt posterior lateral incision. Surgical technique 1, acetabular side reconstruction: anatomical landmark recognition, transverse LIG, acetabular peripheral bony dissection , true acetabular base. The 1-2mm press-fit retains as much subchondral bone as possible, adequate prosthetic coverage is fully seated by press-fit prosthesis, and screw fixation is done if necessary. The cemented prosthesis should be applied so that the cement is embedded 1-2 mm under the cancellous bone of the bone bed to achieve anchorage of the prosthesis to the bone. Ensure that the acetabulum is fitted in a 45-55° abduction and 15-20° anterior tilt position. 2. Lateral femoral reconstruction: recognize the anatomical landmarks, the greater trochanteric fossa, the lesser trochanter, and understand the anterior arch angle of the femur. When opening the medulla, in addition to paying attention to the anterior tilt angle, one should also pay attention to the axis of the femur, which should generally be close to the inner wall of the greater trochanter and point to the medial condyle of the femur to ensure that the stem of the femur is in a neutral or mildly valgus position. Correct preparation of the medullary cavity to achieve a good compression fit avoids the selection of a smaller size femoral stem and reconstructs the proper eccentricity (offset). For original acetabular abnormalities including revision surgery, the offset and limb length should be restored by selecting the neck length according to the center of rotation of the reconstructed acetabulum. Generally, the limb should not be longer than the healthy side after surgery, and 0.5-1mm shorter than the healthy side is acceptable. 3, joint anterior tilt angle: routinely keep the femoral prosthesis stem anterior tilt angle of 15 °, the acetabular prosthesis anterior tilt angle of 15 ° – 20 ° degrees. Brasoum et al. through the computer simulation of the hip research found that the acetabular and femoral prosthesis anterior tilt angle can be compensated for each other, can be adjusted through the placement of one of them to compensate for the other part of the inappropriate placement, so as to make the replacement of the hip joint to obtain a good degree of mobility and stability. Stability. The composite anterior tilt angle should be controlled at 20-35° for men and 30-45° for women. Perioperative management 1. Preoperative assessment of systemic organ function and control of metabolic diseases are important measures to ensure smooth and safe perioperative period. 2, Regular application of anticoagulants to prevent lower extremity deep vein thrombosis (VTE) and pulmonary embolism (PE). It is recommended to apply for 35 days. 3.Formal functional rehabilitation, generally 5-7 days after the operation can help crutches out of bed activities, the application of biological prosthesis can abandon crutches after 6 weeks.