Biomechanical comparison of pedicle subtraxion osteotomy and bone disc bone osteotomy on sheep spine

INTRODUCTION AND AIM: The aim of our study is to compare the tension on the rod with the application of sequential loads in pedicle subtraction osteotomy and bone disc bone osteotomy applied at different angles and to try to prevent possible rod insuffiency fractures that may ocur due to the osteotomy technique. MATERİAL AND METHOD: In this study, 40 sheep vertebrae were used. 10 of them were performed 4 level PSE and 35 degree PSO, 10 of them were performed 5 level PSE and 35 degree BDBO, 10 them were performed of 4 level PSE and 65 degree PSO and 10 of them were performed 4 levels of PSO and 65 degrees BDBO. İncreasing axial loading was applied to the vertebral models and the rod stress were measured with strengech. RESULTS: When the 35 degree PSO and BDBO models were compared, it was seen that the tension on the rod in the PSO model against the sequential axial loads created was higher than that of the BDBO and it was found to be statistically significant (p<0. 05). When the 65 degree PSO and BDBO models were compared statistically, no significant difference was found in the tensions on the rod against the sequential forces. CONCLUSİON: In conclusion, when the PSO and BDBO were compared in 35 and 65 degree, the biomechanical results show that; in low grade sagittal deformities BDBO may cause less related rod fractures. Keywords: Biomechanics, bone disc bone osteotomy, deformity, pedicle subtraction osteotomy, vertebrae