Minimally invasive surgery of total hip arthroplasty (MIS- THA) is a minimally invasive total hip arthroplasty with an incision of less than 10-12 cm, characterized by partial or no severance of muscle and tendon tissues during surgery, minimizing the disturbance of the local anatomical and biological environment of the joint. replacement. Since 2008, we have adopted a modified posterior-lateral small incision for hip arthroplasty, which has the advantages of small trauma (wound less than 10 cm), less bleeding, faster postoperative recovery, no postoperative wound drainage, no severing of the external rotation muscle group, preservation and suturing of the joint capsule, and less postoperative dislocation, etc. We have achieved good results.