PRELIMINARY RESULTS OF ACETABULAR IMPACTION BONE GRAFTING IN CEMENTED TOTAL HIP REPLACEMENT WITH PARTICULAR REFERENCE TO THE USE OF A PREFORMED METALLIC MESH.

Abstract

Impaction bone grafting has become an established technique in restoring acetabular and femoral bone stock loss during hip replacement surgery. This study presents our preliminary results using this technique to restore acetabular bone stock loss during cemented total hip replacement, with particular reference to the use of a preformed perforated metallic mesh to contain major acetabular defects.

In 52 patients (55 hips), acetabular reconstruction with impaction bone grafting was undertaken during total hip replacement (7 primary and 48 revision, of which 13 had previously undergone multiple revisions). The mean age at the time of surgery was 68 (range 34 to 88). In 31 cases (30 segmental or combined acetabular deficiencies, and one case of pelvic discontinuity) a pre-formed stainless steel mesh was utilised to contain the impacted morsellised bone graft. There were no perioperative deaths or deep infections and few complications (2 non-recurrent dislocations and 2 deep vein thromboses). At a mean follow-up of 40 months (range 18 to 91 months) there have been no revisions for any reason. Three patients who died before a minimum follow-up of 18 months have been excluded. Of the 49 patients (52 hips) remaining, clinical hip scores (Merle d’Aubigne and Postel) averaged 5.3 for pain, 4.2 for walking ability, and 5.3 for range of movement (with 16 patients in Charnley group A, 14 in group B, and 19 in group C). There was one case of radiographic loosening, with a radiolucent line > 2mm diameter in all 3 zones of DeLee and Charnley, although the cup has not migrated and the patient remains pain-free. All other cases show radiographic changes suggestive of ongoing graft incorporation.

We consider that the use of preformed metallic meshes extends the scope of impaction bone grafting to include cases where major segmental acetabular deficiencies are encountered, allowing restoration of bone stock and an anatomical centre of hip rotation, with encouraging preliminary clinical and radiological results.