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Objectives and questions: Acetabular defects are the most common problem in revision hip arthroplasty (RHA). The goal of acetabular reconstruction is to restore the hip joint's center of rotation, as well as the integrity and continuity of the acetabulum and preserve as much of the original bone as possible, which ultimately affects the stability of the prosthetic component. Currently, reconstructing acetabular defects and restoring hip biomechanics pose significant challenges due to the individual variability of acetabular defects and the variety of surgical strategies and approaches. The aim of this study was to determine the efficacy of using custom-made acetabular augments in revision hip arthroplasty.

Material and methods: We conducted a prospective cohort study including 28 patients with hip osteoarthritis who underwent RHA. In this group of patients, acetabular defects of stages 3A-3B according to the Paprosky classification were identified during preoperative planning. Preoperative computer tomography was performed in all cases to determine the shape and precise dimensions of the defect area. Image preprocessing, 3D planning, and custom implant fabrication were performed. After agreeing on surgical requirements and technical feasibility, custom augments were fabricated. The surgeries were performed via an extended anterior-external approach with the placement of a custom acetabular augment, a cemented cup, and a modular revision femoral component. The results were assessed 18 months after surgery. Pain, range of motion, functional outcome using the Harris Hip Score (HHS) and the number of complications were assessed. Statistical analysis of the data was performed using the “Statistic” software. The study data are presented as the Median [25%; 75%].

Results: In all cases, the positioning of the custom acetabular augments was successful, without significant deviations from preoperative planning. During surgery, we were able to ensure the stability of the endoprosthesis system and equalize the length of the lower limbs. At the preoperative stage HHS was 23.5 [21; 26]. During the 18-month follow-up period, we observed an increase in the HHS in all cases 73 [70; 78], as assessed by patient questionnaires. Postoperative complications were identified in two patients. In the first case, sciatic nerve neuropathy, in the second early periprosthetic infection.

Discussion and conclusions: The introduction of custom-made acetabular augments into clinical practice significantly expands surgeon options for revision acetabular arthroplasty in cases of extensive bone defects. By integrating modern imaging technologies, computer modeling, and additive manufacturing methods, this method ensures optimal stability of the endoprosthesis system, restores hip biomechanics, and improves patient outcomes.