Trabecular metal augments in severe malignancy-associated acetabular bone loss

Area of Science:

• Orthopaedic Oncology
• Reconstructive Surgery
• Biomaterials Science

Background:

• Acetabular reconstruction presents significant challenges in orthopaedic oncology, particularly for extended bone defects (Paprosky Type 3A and 3B).
• Revision total hip arthroplasty (THA) often requires advanced solutions for severe acetabular bone loss.
• Trabecular metal (TM) augments combined with porous metal acetabular components are an emerging option for complex cases.

Purpose of the Study:

• To evaluate the clinical and radiographic outcomes of using trabecular metal (TM) augments in periacetabular malignant bone disease.
• To assess the efficacy of TM augments in revision total hip arthroplasty (THA) for extensive acetabular defects.
• To determine the complication rates and long-term stability of TM augments in oncological reconstructions.

Main Methods:

• A retrospective review of 15 patients with Paprosky Type 3A or 3B acetabular bone loss due to periacetabular malignancies undergoing THA with TM augments.
• Data collected included patient demographics, tumour type (primary vs. metastatic), defect classification, and follow-up duration.
• Outcomes assessed included postoperative complications, radiological loosening, and need for acetabular component revision.

Main Results:

• The study included 7 primary and 8 metastatic cancer patients with an average follow-up of 23.8 months.
• One patient (6.7%) required revision due to acetabular component loosening at 7 months post-implantation.
• Four patients (26.7%) underwent surgical intervention for infection, with stable TM augments noted at the latest follow-up.

Conclusions:

• Trabecular metal (TM) augments with porous metal acetabular components demonstrate potential as an effective alternative to traditional cemented constructs in challenging acetabular reconstructions.
• TM augments provide a stable fixation option for periacetabular malignant bone defects, with a low rate of revision for loosening.
• While infection remains a concern, TM augments appear to maintain stability in the presence of periacetabular malignancies and complex THA.