Impaction grafting is controversial in the presence of segmental and cavitary acetabular defects and requires the use of supplemental devices to close segmental defects. This approach, however, would allow treating combined deficiencies that could not be managed with impacted cancellous bone alone. We raised the following two questions: (1) What is the survival rate in patients with combined deficiencies reconstructed with metal mesh, impaction grafting and a cemented cup and (2) can metal mesh prevent cup migration? We evaluated 23 cavitary uncontained acetabular defects in revision hip arthroplasty. Preoperative diagnoses were aseptic loosening (19 hips) and second-stage reimplantations after resection for infection (four hips). The preoperative Merle D'Aubigné-Postel score averaged 7.4 points. Two patients had reoperations for mechanical failure at 6 and 24 months. The survival rate with further revision as an end point was 90.8% at an average of 36 months (range, 24-56 months; 95% confidence interval, 68.1-97.6). Metal mesh did not prevent cup migration: migration occurred in all patients, averaging 5.1 mm (range, 2-25 mm). Another three patients with severe combined defects had asymptomatic mesh rupture with 3- to 15-mm migration. Postoperative functional score averaged 16.2 points. Metal mesh, impaction grafting, and a cemented cup should be considered for reconstruction of medium uncontained acetabular defects, but not for severe combined deficiencies.
Level of evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.