Preoperative digital design in artificial total hip arthroplasty for patients with Crowe type III and IV developmental dysplasia of the hip: A case series.

Successful complete artificial total hip arthroplasty for patients with Crowe type III or IV developmental dysplasia of the hip is challenging in clinical practice. This study aimed to explore the accuracy and effectiveness of preoperative digital design for patients with Crowe type III or IV developmental dysplasia of the hip. This case series study included patients with osteoarthritis secondary to developmental dysplasia of the hip who did not respond to conservative treatment and subsequently required total hip arthroplasty in Tianjin Third Central Hospital between January 2018 and February 2020. A total of 20 patients (5 males and 15 females) were enrolled, of whom 12 presented with Crowe type III and 8 with Crowe type IV developmental dysplasia of the hip. Total hip arthroplasty for each patient was successful. The implanted acetabular cups were one size (2 mm) smaller than the preoperatively designed size in four patients, and the implanted femoral stem prosthesis was one size (1 mm) larger than the preoperatively designed size in four patients with type IV DDH. The Harris scores differed significantly between preoperative and postoperative measurements (58.6 vs. 94.4;  = 0.016). No infection or joint dislocation was observed. Preoperative digital modeling may be used to predict the size of prosthesis required and location for implantation in patients undergoing total hip arthroplasty.