MEDIUM TERM RESULTS OF IMPACTION ALLOGRAFTING WITH GAMMA IRRADIATED DONOR BONE

Abstract

One of the major surgical challenges at revision arthroplasty is the management of bone stock loss in the acetabulum.

There are several options available for reconstruction; cemented sockets within thick cement mantles, custom sockets jumbo uncemented sockets, support rings and bone grafting. Slooff and others have shown good results with impaction grafting.(JBJS 80B 1998)

If one is to use bone graft, does the preparation of the graft have any effect on the graft itself? There are a number of ways bone can be presented, freeze dried, fresh frozen or frozen irradiated. Concerns have been raised that irradiated bone has an altered and weakened structure. There is a paucity of clinical results on this subject. In this study we present a series of patients using gamma irradiated bone for reconstruction.23% of the cases reconstructions secondary to failure due to sepsis.

Between 1987 and 2000 192 revision arthroplasties in 165 patients were performed with irradiated morcellised bone allograft for acetabular reconstruction. Only those patients with a minimum follow up of 24 months were reviewed. Clinical and radiological follow up was achieved in 130 hips in 115 patients. 9 patients had died at a range of 1 to 66 months after surgery. There were 23 (17%) re-revisions of the acetabular component. Of these 13 were for deep sepsis, 5 for persistent early dislocation and 4 for aseptic loosening. Of those hips revised for infection there was a 13% re-revision rate for reinfection. There was only one catastrophic failure of the graft and only three re-revisions for aseptic loosening to date.

We feel that impaction grafting of the acetabulum is a useful technique for reconstruction even when the index arthroplasty failed for sepsis. We have found no evidence to show that gamma irradiated bone performs any worse than other types of allograft bone.