Outcomes of Indication-Based Reconstruction Strategies in a Retrospective Observational Cohort of Patients with Paprosky Type IIC Acetabular Defects

Background/Objectives: Paprosky Type IIC acetabular defects encountered during revision total hip arthroplasty (rTHA) present substantial challenges in terms of surgical planning and implant stability. This study evaluates the outcomes of indication-based reconstruction strategies using dual mobility cups (DMC) and reconstruction cages (RC) in patients with Paprosky Type IIC acetabular defects. Methods: This retrospective, non-randomized study included 41 patients who underwent revision total hip arthroplasty for Paprosky Type IIC acetabular defects between 2014 and 2023, reflecting an indication-based treatment strategy. Patients were categorized into two groups: the DMC group (n = 25) and the RC group (n = 16). Clinical evaluation was performed using the Harris Hip Score (HHS), while radiographic assessment focused on the restoration of the hip center of rotation. Complications, revision rates, and implant survivorship were also analyzed. Results: Both groups demonstrated significant functional improvement; however, the differences in postoperative HHS were observed between groups (86.1 vs. 74.7; p < 0.001). The DMC group also showed a shorter operative time, reduced blood loss, and a shorter hospital stay (p < 0.05). Although the dislocation rate was lower in the DMC group (4% vs. 12.5%), the difference was not statistically significant. The overall complication rate was markedly higher in the RC group (68.8% vs. 28.0%; p = 0.010). Implant survivorship was high in both groups (92.7%), with no significant difference between them. Mean follow-up duration was 49.9 ± 16.0 months. Conclusions: Both dual mobility cups and reconstruction cages can achieve successful outcomes in revision total hip arthroplasty for Paprosky Type IIC acetabular defects. However, the observed differences in perioperative and functional outcomes should be interpreted within the context of indication-based patient selection and do not imply superiority of one reconstruction strategy over the other. Rather, these findings reflect outcomes of reconstruction strategies applied according to defect reconstructability in a real-world clinical setting.