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Background: pedicle screw fixation system because it runs through the three-column, fixed and strong and become the most widely used in today's clinical posterior spinal fixation devices for the treatment of fractures, deformity correction, reconstruction after tumor resection, spinal instability, as well as spinal degenerative disease and other illnesses. Senile osteoporosis patients with fragile bone pedicle screw fixation capacity decline. Ways to make use of bone cement augmentation of pedicle screw screws ability, but the leakage of bone cement and screws out of the difficulties of this method is plagued two problems. Therefore, the research on the strengthening of pedicle screw method has been the subject of concern is the people. Objective: To design a new infusion of bone cement pedicle screw (Novel Perfusional Pedicle Screw, NPPs) with the the bone cement putter and Tubular application, the use of new bone cement perfusion method to explore in osteoporotic vertebral safe, practical, biomechanical stability, for clinical treatment of spinal disorders associated with osteoporosis provides a good stability of the new pedicle screws. Methods: select an average age of 73 years complete wetting spine specimens (T 11 -L 5 ) 6 with a total of 42 vertebrae, mean BMD to 0.696 ± O. 14g/cm 2 . All vertebral pedicles take any side infusion of bone cement pedicle screw, the use of bone cement putter and Tubular X-ray through the infusion of bone cement pedicle screw to the vertebral body perfusion group like the initial bone cement 2ml, contralateral pedicle into the conventional screw as the control group and observed by X-ray bone cement diffuse the situation. Randomly selected three vertebrae, cut open the Open vertebral the observed bone cement distribution. More than 39 vertebrae were randomly divided into 3 groups (n = 13), respectively the maximum axial pull-out strength experiments, maximum rotary torque experiments, the periodic bending resistance test was, and observed the destruction of the vertebral body. In another three-point bending test of the screw line of 10 new screws and 10 in the control group. Results: All the vertebral bone cement dispersion screw distal end side around the hole in the vertebral body, bone cement leakage was not observed. The infusion of bone cement screw pullout force of 760 ± 178 N, the control group was 355 ± 87N (P lt; 0.01). The infusion of bone cement screw screwed out torque of 1.347 ± 0.377 N · m, the control group was 0.488 ± 0.205 N · m (P lt; 0.01), vertebral body and pin tract without damage. Infusion of bone cement screws only four (4/13, 30.8%), the average load of loose screws, loose screws approximately 150 ± 46N, not loose screws, loose displacement average of only 0.661 ± 0.289mm, the control group all the screws at maximum load between 50-200N began to loosen (displacement gt; 2.0mm), with an average load of 104 ± 35N. The infusion of bone cement screws average ultimate bending load of 3082 ± 144N, the screws of the control group to 3357 ± 263N (P GT; 0.05). Conclusion: The new design of the perfusion bone cement pedicle screws with bone cement putter and Tubular application, easy to operate, effective control of cement leakage significantly enhanced pedicle screws in osteoporotic vertebral stability, and remove the screws, no damage to the vertebral body and the screw channel.
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