Use of Custom-Designed Additive-Manufactured Acetabular Components for Reconstruction of Paprosky Type III Acetabular Defects in Revision Hip Arthroplasty: A Single-Center Case Series

Background/Objectives: To evaluate the short-term clinical and radiological outcomes of using custom-designed additive-manufactured acetabular components (CDAMACs) in revision total hip arthroplasty for patients with Paprosky type IIIA-IIIB acetabular defects. Materials and Methods: A retrospective single-center case series was conducted. Between 2020 and 2025, 19 patients with massive Paprosky type IIIA-IIIB acetabular defects underwent revision hip arthroplasty with CDAMACs. Preoperative planning was based on multislice computed tomography data, followed by 3D modeling and implant design. Perioperative parameters, functional outcomes (Harris Hip Score [HHS], WOMAC, Visual Analog Scale [VAS] for pain), and radiographic parameters (restoration of the center of rotation, component stability) were assessed. Minimum follow-up was 12 mo. Results: The mean operative time was 155 ± 24 min, and the mean blood loss was 718 ± 288 mL. At 12 mo, significant functional improvements were observed: the mean HHS increased from 37.5 ± 5.2 to 74.5 ± 8.6 points, WOMAC decreased from 74.5 ± 9.2 to 40.3 ± 7.6 points, and VAS decreased from 7.6 ± 1.0 to 2.8 ± 0.7 points (p < 0.001 for all). Restoration of the hip center of rotation was determined. Minimum follow-up was 12 mo. No component migration or progressive radiolucent lines were observed. Complications occurred in two patients (10.5%), with only one case directly related to the acetabular component. Conclusions: The use of CDAMACs in revision hip arthroplasty for severe Paprosky type IIIA-IIIB acetabular defects is associated with satisfactory short-term clinical, functional, and radiological outcomes. This technique enables restoration of the center of rotation and provides stable component fixation in complex anatomical conditions.