Allogeneic segmental fibular transplants in azathioprine-immunosuppressed dogs
Burchardt, H.; Glowczewskie, F.P.; Enneking, W.F.
Journal of Bone and Joint Surgery. American Volume 59(7): 881-894
1977
ISSN/ISBN: 0021-9355 PMID: 332701 Document Number: 122386
A bilateral segmental fibular autogenous graft or an autogenous segmental graft on one side and an allogeneic graft on the other were performed on 4 groups of adult male mongrel dogs. Some of the dogs were immunosuppressed with azathioprine according to the following protocol: bilateral autograft with no azathioprine therapy; bilateral autograft with azathioprine therapy; allograft on one side and autograft on the other with no azathioprine therapy; and, allograft on one side and autograft on the other with azathioprine therapy. At 6 mo. postoperatively, repair processes in the 4 groups were compared using roentgenograms, torsional stress testing, tetracycline labeling and microradiography. Azathioprine therapy did not affect normal autograft healing. In the untreated dogs, fatigue fractures of the allografts and non-union of their host-graft junctions were frequent and there was increased or total resorption of the transplants, indicating that the allogeneic grafts were rejected by the host immune response. Azathioprine therapy partially suppressed the immune response of the recipients to the allografts so that 50% of the allogeneic transplants in the treated dogs were incorporated into the host skeleton in a manner that was comparable to the incorporation of the autografts.