Treatment of Acetabular Fractures by Acute Arthroplasty: A Comparison of Trabecular Metal Cages With a Cemented Bimobile Acetabular Component Versus a Polyethylene Liner

Introduction: The treatment of acetabular fractures with pelvic reconstruction is technically challenging and labor-intensive and carries high complication rates. This retrospective review compares the treatment of acetabular fractures with a trabecular metal cage with a cemented bimobile acetabular component versus a cemented polyethylene liner and dual mobility articulation, in addition to open reduction internal fixation (ORIF) of the acetabulum. Methods: This retrospective single surgeon review included all patients aged 18 or older who presented with an acetabular fracture between 2015 and 2025 at an academic, tertiary trauma and elective arthroplasty referral center (UF Health Gainesville). The surgical technique included treatment with a trabecular metal cage with a cemented polyethylene liner or a metal bimobile acetabular component. Results: Forty-six patients were included in the final sample, 26 in the metal bimobile component group and 20 in the polyethylene component group. Patients receiving a polyethylene component (63.3±14.9) were significantly younger than those receiving a metal bimobile component (73.1± 10.7, p=0.03). Patients receiving a polyethylene component had a shorter hospital length of stay than patients receiving a metal bimobile component (p=0.02). The rate of heterotopic ossification was similar between groups at a minimum of six months post-surgery, as assessed via Brooker classification. Conclusions: We found comparable outcomes in the treatment of acetabular fractures with a trabecular metal cage using either a cemented bimobile component or a polyethylene liner with subsequent ORIF. Either component may serve in fixation for elderly acetabular fractures, particularly in patients with pre-existing osteoarthritis, osteoporosis, concomitant femoral head fractures, and marginal impaction.