The Use of Tail Vertebra as Cortical Bone Graft in Experimentally Induced Ulnar Defects in Dogs

Objective- To evaluate tail vertebra as an autogenous cortical bone and cancellous bone for filling ulnarsegmental bone defect in dogs.Design- Experimental study.Animals- Eight adult mongrel dogs with an aver age age of 37.S months and average body wei ght of17.62 kg.Procedure- Th e animals were randomly divided into two groups . A bone defect (2.S-cm) was created onthe middle po rtion of the right uln a in all do gs. Uln a was fixed by intramedullary pinning. In 5 dogs (tes tgroup) uln ar bone de fects were fill ed with tail vert ebra, after tail docking. Cancellous bone harvested fromthe il iac cres t was also used to promote bone healing in the ho st-graft inter face s. In the other 3 do gs(contro l gro up) ulnar bon e defect s were not fill ed . Po stoperative clinical assessment was includ edmeasurement of body temperature, heart rate, respiratory rate, and evaluation of the degree of lameness.Radiogr aphic assessment of bone based on the process of bone healing and co nsolida tion of the host-gr aftinterface , periosteal reaction, and soft tissue swelling were performed immediate ly and at the weeks 1, 3, S,7, 10, 13 and 17 afte r surge ry.Results- Significant difference (P O.OS) in the degree of lameness and soft tissue swelling were observedbetween the two groups. Th e difference of the mean of per iosteal reaction was not significant between thetwo groups. Bone healing process was completed in the co rt ical autograft group and clinical union wasobserved in 100% of dogs in comparison with nonunion in 100% of animals in the control group.Conclusion and Clinical Relevance- The resul ts of this study showed that tail vertebra ca n be used asan excellent material for filli ng of seg mental uln ar bone defects in dogs.