Three dimensionalprinted titanium block to reconstruct severe acetabular bone defects in primary hip arthroplasty.

Abstract

Purpose: Total hip arthroplasty (THA) with severe acetabular bone defect remains a challenge in clinic. The purpose of this study is to investigate the treatment technique by using the three-dimensional (3D) printing technology, and analyze the feasibility and preliminary effect of 3D printed personalized titanium blocks for acetabular defect reconstruction in primary THA.

Methods: The clinical data of 35 patients with Paprosky type 3 acetabular defect, who underwent initial THA with 3D-printed titanium implants in our hospital from January 2017 to December 2019, were retrospectively analyzed. Among them, 21 cases were Paprosky type 3 A bone defects and 14 cases were Paprosky type 3B bone defects. The Harris Hip Score (HHS) was used to evaluate clinical outcomes, while imaging results were analyzed by hip rotation centres (V-COR and H-COR). In addition, postoperative complications were recorded.

Results: The mean follow-up was 79.4 months (ranging from 63 to 94 months) and no patient was lost to follow-up. The total in-hospital blood loss of all patients was 462.9 ± 227.8 mL, accompanied with a blood transfusion rate of 31.4%. HHS improved from 44.5 ± 10.0 preoperatively to 85.1 ± 7.4 at the last follow-up (p < 0.001). Postoperative X-rays exhibited a good match between the 3D-printed titanium block and the acetabulum. V-COR decreased from 50.1 ± 4.7 mm preoperatively to 19.7 ± 1.8 mm postoperatively (p < 0.001). Similarly, H-COR improved from 33.1 ± 11.8 mm preoperatively to 29.7 ± 1.7 mm postoperatively (p > 0.05). Additionally, there were no significant changes in V-COR and H-COR at the last follow-up (p > 0.05). During follow-up, three cases of complications were observed, including two cases of wound redness and one case of partial sciatic nerve paralysis.

Conclusions: The 3D-printed personalized titanium block revealed accurate reconstruction, satisfactory radiographic and clinical outcomes, and low complication rates. This technique provides a reliable treatment strategy for primary THA in patients with severe acetabular bone defect.