ACETABULAR RECONSTRUCTION USING IMPACTION BONE GRAFTING AND WIRE MESH

Abstract

During arthroplasty acetabular deficiencies could be reconstructed using different techniques. We describe our early results of acetabular reconstruction using impaction bone grafting supported by a wire mesh.

This is a retrospective review of 45 patients (46 hips, 1 bilateral) who had acetabular reconstruction with impaction bone grafting and wire mesh between 1995–1999. The average follow up was 36 months (18–54 months). Mean age at operation was 70 years (41–88 years). 28 were primary (osteoarthritis) and 18 were revisions (painful aseptic loosening). Paprowsky’s classification was used to grade the defects – 44 hips: grade II, 2 hips: type III A. Containment was achieved with a wire mesh anchored with screws. The defect was filled with morcellised bone graft, which was impacted under the mesh (autograft in primary and allograft in revisions). Cemented Exeter components were used. Merle d’Aubigné Postel hip score and AAOS proforma was used during follow-up and cup migration was assessed using Nunn and Freeman’s method.

Merle d’Aubigné Postel score showed improvement of at least 10 points in each patient (Charnley prefix: type A – 27 patients; type B – 10 patients; Type C – 8 patients) Mean vertical and horizontal cup migration of 2.6 mm each was seen, which was not statistically significant (at 5% level). Graft incorporation was seen in all radiographs. 32 hips showed a thin sheet of new bone over the superolateral surface of the mesh which was regarded as a sign of good graft incorporation. There were no complications specifically related to the wire mesh or screws (1 – superficial wound infection, 2-DVT, 2- dislocations treated conservatively). None of the patients required further revision surgery.

We are encouraged by our early results of this method for reconstruction of peripheral acetabular rim deficiencies because it restores anatomy, biomechanics, replaces bone loss and provide a stable construct.