XIII. International Turkish Spine Congress, İzmir, Turkey, 3 - 06 April 2019, pp.56
BIOMECHANICAL COMPARISON OF THREE DIFFERENT SCREW DESIGNS IN OSTEOPOROTIC SPINE FIXATION PURPOSE: The aim of this study is to biomechanically compare standart pedicle screw, dual-threaded pedicle screw, and cemented dual threaded pedicle screw in an osteoporotic spine model MATERIALS AND METHODS: Twenty-four synthetic osteoporotic bone blocks were separated to 3 groups, according to the screw designs: 1) standart pedicle screw; 2) dual-threaded pedicle screw; 3) cemented dual-threaded pedicle screw. Samples were placed on a universal testing machine and pullout loads were measured. Independent samples Kruskal-Wallis test was utilized within 95% confi dence interval and p value <0.05 to test for statistical signifi cance. RESULTS: The mean pullout strength was 32.72 N (SD±12.53) in Group 1, 37.87 N (SD±19.29) in Group 2, and 78.46 N (SD±23.59) in Group 3. The results were statistically signifi cant (p<0.05). Inter-group comparisons revealed that cemented pedicle screws had a signifi cantly higher pullout strength (Group 1-3 p= 0.003, Group 2-3 p= 0.015). Although dual-threaded screws had higher pullout strengths when compared with standart pedicle screws, the difference was not statistically signifi cant (p=1.00).CONCLUSION: Our results showed that cemented pedicle screws had signifi cantly higher pullout strength. To achieve a more stable fixation in osteoporotic patients, cemented dual-threaded screws will be a good option.