CAJ | 학술논문

目的评价一种基于椎弓根螺钉的新型聚醚醚酮树脂(PEEK)动态稳定内固定系统的生物力学特性. 方法将整套测试装置加载于试验机上进行静态测试(压弯、拉伸和扭转)和疲劳测试.静态压缩弯曲与拉伸弯曲试验采用位移控制加载,以25 mm/min速率将内固定系统压或拉至破坏；静态扭转试验采用扭转角度控制加载,以60°/min的速率将结构物扭转至极限状态.疲劳试验采用载荷控制的压弯疲劳加载,加载的波形为正弦波,加载频率为5 Hz,载荷比为10,循环极限次数为500万次. 结果 PEEK动态稳定内固定系统静态压缩弯曲2％变形位移为1.52 mm,弹性位移为(6.39±1.80) mm,屈服载荷为(1505.86±189.17)N,压弯刚度为(236.16±59.64) N/mm,极限载荷为(1649.05±206.46)N；静态拉伸弯曲2％变形位移为1.52 mm,弹性位移为(24.86±5.71) mm,屈服载荷为(2041.50±605.80)N,拉弯刚度为(28.70±7.47) N/mm,极限载荷(2424.51±625.82) N;静态扭转2％变形角位移为1.95°,弹性角位移为8.73°±3.69°,屈服扭矩为(6.48±1.93)N·m,扭转刚度为(0.73±0.20) N/mm,极限扭矩为(9.31±1.12)N·m.脊柱内固定系统疲劳极限载荷参考值为1000 N. 结论 PEEK动态稳定内固定系统具有较好的动态稳定性,且能保留固定节段活动度.
목적 평개일충기우추궁근라정적신형취미미동수지(PEEK)동태은정내고정계통적생물역학특성. 방법 장정투측시장치가재우시험궤상진행정태측시(압만、랍신화뉴전)화피로측시.정태압축만곡여랍신만곡시험채용위이공제가재,이25 mm/min속솔장내고정계통압혹랍지파배；정태뉴전시험채용뉴전각도공제가재,이60°/min적속솔장결구물뉴전지겁한상태.피로시험채용재하공제적압만피로가재,가재적파형위정현파,가재빈솔위5 Hz,재하비위10,순배겁한차수위500만차. 결과 PEEK동태은정내고정계통정태압축만곡2％변형위이위1.52 mm,탄성위이위(6.39±1.80) mm,굴복재하위(1505.86±189.17)N,압만강도위(236.16±59.64) N/mm,겁한재하위(1649.05±206.46)N；정태랍신만곡2％변형위이위1.52 mm,탄성위이위(24.86±5.71) mm,굴복재하위(2041.50±605.80)N,랍만강도위(28.70±7.47) N/mm,겁한재하(2424.51±625.82) N;정태뉴전2％변형각위이위1.95°,탄성각위이위8.73°±3.69°,굴복뉴구위(6.48±1.93)N·m,뉴전강도위(0.73±0.20) N/mm,겁한뉴구위(9.31±1.12)N·m.척주내고정계통피로겁한재하삼고치위1000 N. 결론 PEEK동태은정내고정계통구유교호적동태은정성,차능보류고정절단활동도.
Objective To clarify biomechanical characteristics of the pedicle screw-based polyetheretherketone (PEEK) dynamic stabilization system.Methods Mechanical tests were performed following the guideline of ASTM F1717-04 to determine the mechanical characteristics of the 6.35 mm PEEK rod under static and dynamic loading conditions.Static compression bending tests were conducted in the ElectroForce(R) 3510instrument and in displacement control at a rate of 25 mm/min until failure occurred; failure was defined as either fractureofanimplantoranoticeablereductioninstiffness.Load and displacement data were collected.Static torsion tests were conducted in the same machine and under rotation control at a rate of 1 degree/s until a rotational displacement of 30 degrees was reached or failure occurred.Torque and rotation data were again collected.Dynamic compression tests were performed in sinusoidal displacement control using an R ratio equal to 10,and at a maximum frequency of 5 Hz and in ambient conditions.Each specimen was dynamically loaded until fracture of the implant occurred or 5 million cycles had occurred.Results The static compression bending tests showed that the mean and standard deviation of the displacement at 2％ offset was 1.52 mm,elastic displacement 6.39 ± 1.80 mm,compressive bending yield load 1505.86 ± 189.17N,compressive bending stiffness 236.16 ± 59.64 N/mm,and compressive bending ultimate load 1649.05 ± 206.46 N.The static tension bending tests showed that the mean and standard deviation of the displacement at 2％ offset was 1.52 mm,elastic displacement 24.86 ±5.71 mm,tensile bending yield load 2041.50 ± 605.80 N,tensile bending stiffness 28.70 ± 7.47 N/mm,and tensile bending ultimate load 2424.51 ± 625.82 N.The static torsional tests showed that the mean and standard deviation of the angular displacement at 2％ offset was 1.95°,elastic angular displacement 8.73° ± 3.69°,yield torque 6.48 ± 1.93 N · m,torsional stiffness 0.73 ±0.20 N/mm,and ultimate torque 9.31 ±1.12 N · m.The reference value for the endurance ultimate load of the internal fixation of the spine was 1000 N.Conclusion The PPDS provides dynamic stability in case of instrument segments and preserves motion at the operative level.