Reconstructing tumour defects: lyophilised, irradiated bone allografts

Tumour excision leaves behind large defects. Allografts provide an excellent alternative to autografts without donor site morbidity and are especially useful in large defects or in children where the quantity of available autograft is limited. In this paper we discuss our experience with indigenously procured and processed lyophilised, irradiated bone allografts. Bone allografts were used in 41 patients. They were used morsellised and used in 32 cases. Of these, 25 cases were available for follow-up. These included 21 patients in whom the allograft was used in contained cavities. Complete incorporation of the graft was seen between 6 and 9 months in all these 21 patients. In 4 patients the allograft was layered onto autograft. In only one of these the allograft incorporated with the host bone. Struts were used in 9 cases (3 cases complete intercalary segmental defect, 3 cases of hemicortical defects, 2 cases of allograft-prosthesis composite around the hip, in 1 case an iliac-crest block was used to stop bleeding from an anterior sacral defect). Of these, 2 full segment struts showed no incorporation. Both these patients were on chemotherapy and radiotherapy. There was no follow-up in sacral defect case. All the other struts incorporated with the host bone within 6-9 months.In 5 cases there was sterile postoperative drainage. All these cases went on to uneventful. Deep infection was observed in 4 patients (10%). In one, the graft was removed, another settled uneventfully with subsequent incorporation of graft, and two have a persisting sinus but good incorporation.To restore part of the strength of the struts it was necessary to hydrate them for 30 min prior to use. Autogenous marrow or autograft was used to provide osteoinductive properties.Conclusion. In selected cases the lyophilised, irradiated bone allografts proved to be very useful in reconstruction of large tumour defects.