摘要
目的 评估固态压缩增强的高强度可吸收左旋聚丙交酯 (SC PLLA)作为接骨材料的价值。方法 SC PLLA棒植入新西兰兔股骨髓腔内 ,定期取出测量试棒的力学强度 ,观察其周围组织的反应 ;分别应用SC PLLA棒和不锈钢针 ,髓内固定股骨干横行骨折 ,比较两组的X线影像学变化。结果 植入 2 4周后 ,SC PLLA棒的弯曲强度下降 30 % ,为 180MPa;剪切强度下降 6 0 % ,为 76MPa。植入 4周后 ,试棒周围有增生活跃的骨组织 ;12周后 ,组织反应基本稳定 ,见板状骨平行于试棒排列 ,内植物—骨组织之间有一薄层的纤维组织。SC PLLA棒和不锈钢针髓内固定股骨干横向截骨均未见明显畸形 ,X线观察显示各期的骨痂量基本相当。结论 SC PLLA的强度能满足长骨干固定的需要 ,髓内固定效能与不锈钢钉相当。SC PLLA在骨内具有良好的组织相容性。
Objective To evaluate the bioresorbable, high-strength solid-state compression reinforced poly-L-Lactide (SC-PLLA) used as the material of osteosynthesis. Methods The SC-PLLA rods (3.2 mm×40 mm) were implanted in the femoral medullary cavities of 18 New Zealand rabbits and removed at 4, 8, 12, 24, 36, and 48 weeks postoperatively, respectively. The mechanical strength of the rods (3 point bending strength and shear strength) and the interfacing reaction between the rods and the bone were studied. 7 rabbits femoral diaphyseal transversal osteotomies were fixed with SC-PLLA rods (4 rabbits) or stainless steel pins (3 rabbits), intramedullaryly. The fixation effectiveness was compared with radiographs. Results At 24 weeks postoperatively, the bending strength of the SC-PLLA rods decreased 30%, and the shear strength decreased 60%. The values of the bending strength and the shear strength at this time were 180 MPa and 76 MPa, respectively. These reached at the level of human femoral diaphysis. After 4 weeks of implantation, the bone in the vicinity of the rods proliferated actively. The trabeculae of the newly formed bone arrayed irregularly. After 12 weeks, the bone became mature, enclosed the rods, arrayed lamellarly and paralleled the rods longitudinally. A thin layer of fibrous tissue appeared interposing the bone and the implants. There were no significant deformities in all the osteotomies intramedullaryly fixed with SC-PLLA rods or stainless steel pins. And the callus quantities of the two groups corresponded. Conclusion The mechanical strength of SC-PLLA is sufficient for the fixation of diaphyseal fracture of long bone, and the effectiveness of intramedullary fixation with which is similar with that of stainless steel pins. The SC-PLLA has good tissue biocompatibility in bone.
出处
《临床骨科杂志》
2004年第2期213-216,共4页
Journal of Clinical Orthopaedics
基金
中国博士后科学基金资助课题 (文号 :中博基〔2 0 0 1〕5 )
关键词
牛物相容材料
生物降解
左旋聚丙交酯
生物力学
组织相容性
骨折固定术
内
biocompatible materials
biodegradation
poly-l-lactide
biomechanics
histocompatibility
fixation fracture, internal
