Artificial total hip arthroplasty has become the best option for the treatment of patients with advanced DDH complicated by severe osteoarthritis, and the local anatomical abnormalities of the hip joint in these patients make it technically challenging for the orthopaedic surgeon. The main technical point is to reconstruct the abnormal acetabulum and femur and to restore the correct length of the affected limb. In severe or completely dislocated hip dysplasia, it is difficult to reconstruct the center of rotation of the hip and restore the length of the lower extremity, both of which are important factors in the longevity of the prosthesis. At present, there is still a great controversy on how to reconstruct the center of rotation of the hip joint and restore the length of the lower limb. However, the basic view is that the acetabular prosthesis should be placed as far as possible in the true socket and should ensure satisfactory accommodation of the prosthesis while restoring the length of the lower extremity, with the position of the acetabular prosthesis being the key to arthroplasty. This view is appropriate for the majority of patients with hip dysplasia secondary to osteoarthritis, but may not be true for older patients. The primary indications for treatment with arthroplasty in elderly patients with DDH are pain relief and appropriate improvement of joint function. Due to age and physiological conditions, postoperative mobility is significantly lower in elderly patients than in other DDH patients who are relatively young and active, and therefore joint wear and tear is significantly lower; and elderly patients have relatively low visceral functional reserves, which make it difficult to tolerate the relatively complex joint reconstruction and the subsequent longer postoperative rehabilitation process. Therefore, for such patients, it is a wise choice to adopt a relatively simple and effective joint reconstruction method according to the actual situation. My own case: In April 2012, a 71-year-old woman came for surgery after 16 years of left hip pain, which had been aggravated for one year, and she was basically unable to walk. At that time, she did not leave her walking images, and it was only in October 2014 when she had a follow-up consultation that this photo was left.