Acetabular revision arthroplasty using trabecular titanium implants.

Purpose: The aim of this study was to evaluate early results of acetabular revisions of total hip replacement using fully cementless trabecular titanium (TT) acetabular modular implants (Delta Trabecular Titanium, Limacorporate, Udine, Italy).

Methods: Between March 2009 and May 2012 TT was used in 81 revisions. The mean age at the time of revision was 68 years (32-84 years). There were nine patients revised for type 1, 11 for type 2A, 27 for type 2B, six for type 2C, 15 for type 3A and 13 for type 3B acetabular defects according to the Paprosky classification. Frozen morselised bone allografts were used in 53 cases and bulk structural allografts in three cases. Clinical evaluations were made using a modified functional Merle d'Aubigné-Postel score. The mean follow-up period was 38.14 months (24-62 months).

Results: The mean pre-operative Merle d'Aubigné-Postel functional score was 4.7 and 9.8 at the time of last follow-up. There was one revision due to instability of the acetabular component. A cage system-Delta Revision TT-was successfully used in this case. Three cases with Paprosky type 3B defect showed cranial migration of the acetabular component by 6 mm, but stabilised after six months. No dislocations associated with acetabular surgery have occurred in the cohort. There have been no dissociations of the modular component. A fatigue fracture of the hemispherical module occurred in the revised case. No other hardware mechanical failures have been recorded.

Conclusions: TT cups, hemispherical modules and augments facilitate reliable and reproducible biological fixation in acetabular revision surgery with excellent results. Extended follow-up is necessary to evaluate the long-term performance of TT modular implants.