EARLY RESULTS OF TRABECULAR METAL BACKED ACETABULAR COMPONENTS IN REVISION HIP ARTHROPLASTY.

Abstract

Introduction: Porous Tantalum has been used in a variety of clinical settings since 1997. The use of trabecular metal backed prostheses and augments in the revision hip scenario is attractive due to the higher propensity of bony ingrowth than traditional porous coatings, and also the high coefficient of friction with bone leads to excellent press fit.

We describe the early results of twenty trabecular metal backed acetabular components in the revision setting.

Methods: From 2004, 20 patients received trabecular metal backed acetabular components as a revision hip procedure. The average age of the patients was 69 (42–84) yrs at the time of surgery. 4 patients had trabecular metal shells with cemented liners, 16 patients had modular trabecular metal implants. Structural allograft was used in 2 cases, trabcular metal augment in 1. Revision was for aseptic loosening in 17 cases, infection in 3. Acetabular defects were graded according to Paprosky as 2A(10), 2B(1), 2C(1), 3A(6) and 3B(2).

Fixation was augmented in all cups with at least one screw.

Patients were evaluated with standard x-rays for osteolysis and migration, Harris hip score, SF 36 and Oxford hip score.

Results: Average follow up was 12 months (24–5). 100% follow up was achieved. There were no complications directly related to the acetabular surgery.

There were no revisions. There are no progressive radiolucencies or detectable migration in any of the cups. There were no dislocations.

Conclusion: These early results suggest that trabecular metal backed acetabular components may be confidently used in the setting of hip revision surgery and show promise for the more severe defects for which a reliably reproducible solution has yet to be proven.