RESUMO
To evaluate the induction of osteogenesis of combined autogenous cancellous bone graft and bone marrow in experimental midshaft tibial bone defect. Experimental study. Seven adult mixed-breed dogs with an average age of 1.57 years and an average weight of 22.57 kg. the animals were randomly divided in to experimental [n=5] and control [n=2] groups. In each dog a bone defect [2.5 cm] was created on the midshaft of left tibia and fixed by plate and screws. In the experimental group, tibial bone defect was filled with autogenous cancellous bone and bone marrowo. These matter were harvested from the iliac crest and the medullary canal of the femur, respectively. In the control group, the defect was not filled. Postoperative clinical assessment including measurement of body temperature, heart rate, respiratory rate and evaluation of the degree of lameness was done. Moreover, radiographic assessment of bone based on the process of bone healing periosteal reaction and soft tissue swelling were done before surgery, immediately after surgery and then 1,2,3,5,9,13 and 17 weeks after surgery. The degree of lameness in experimental group was lesser than the control ones from the day 12 to 49 [p<0.05]. Significant difference was observed in the degree of soft tissue swelling between two groups at the week 5 [p<0.05]. Moreover, difference of the periosteal reaction was not significant between two groups. The degree of bone healing process was significantly greater in the experimental group compare to control [p<0.05]. While clinical union was seen in the experimental group up to 100% [n=4] and 75% [n=1], it was not seen in the control group. The result of this study showed that the autogenous cancellous bone and bone marrow can be a reliable method for filling of 2.5 cm segmental tibial bone defect in dog. In this regard, healing of the higher size of bone defect needs to be further investigated