AUTOGENOUS CANCELLOUS BONE-GRAFT INCORPORATION IN A GAP DEFECT IN THECANINE FEMUR

While gap defect models provide greater graft stability and are more r epresentative of many clinical situations than segmental defect models , the hearing in these models has not been well documented. To study t he histologic course of cancellous bone graft healing in a long bone g ap defect, 12 adult mongrel dogs were killed in groups of two at 1, 2, 3, 4, 6, and 12 weeks. Graft incorporation in these dogs was studied using macro- and microradiography, histologic sections, and computer-a ssisted digital surface analysis; results are described. Unlike that s een in segmental defect models, the pattern of repair in a cancellous bone grafted gap defect provides consistent healing at 12 weeks and fo llows the same healing process seen with stable defects.