Novel bicolumnar fixation with primary cup implantation for pelvic discontinuity in revision hip arthroplasty: a comparative clinical study

BACKGROUND: Pelvic discontinuity is a rare but challenging condition in revision hip arthroplasty. Traditional cage-based reconstruction techniques often rely solely on mechanical fixation and may be associated with implant migration, loosening, and mechanical failure. Alternative strategies aimed at restoring pelvic continuity and achieving biological fixation may improve construct stability and clinical outcomes. METHODS: This retrospective study included 19 patients with intraoperatively confirmed pelvic discontinuity who underwent revision total hip arthroplasty between 2014 and 2024. Patients were divided into three groups according to the reconstruction technique used: Group 1 (n = 8) underwent anti-protrusio cage reconstruction alone, Group 2 (n = 6) received additional anterior quadrilateral surface plating prior to cage implantation, and Group 3 (n = 5) underwent restoration of pelvic continuity through anterior and posterior column fixation followed by implantation of a porous-coated primary acetabular cup. Clinical and radiological outcomes were assessed with a minimum follow-up of 2 years, including complications, loosening, reoperation, and reoperation-free survival. RESULTS: Nineteen patients (mean age 71.2 years) with intraoperatively confirmed pelvic discontinuity were included. Aseptic loosening rates differed significantly among the three groups (P = 0.039), occurring in 50% of patients in Group 1 and in none of the patients in Groups 2 or 3. Reoperation rates were higher in Group 1 (75%) than in Group 2 (16.7%) and Group 3 (20%), although this difference did not reach statistical significance (P = 0.074). Kaplan-Meier analysis demonstrated a trend toward lower reoperation-free survival in Group 1; however, differences among the groups were not statistically significant (log-rank P = 0.237). CONCLUSION: Reconstruction strategies involving restoration of pelvic continuity through column stabilization may provide improved mechanical stability and lower complication rates compared with conventional cage-only techniques in the management of pelvic discontinuity. In selected patients, bicolumnar fixation followed by implantation of a porous-coated primary acetabular cup may offer the additional advantage of biological fixation. Larger prospective studies are needed to validate these findings.