植钉部位和骨水泥强化对髂骨钉固定强度的生物力学影响  

BIOMECHANICAL EFFECTS OF INSERTION LOCATION AND BONE CEMENT AUGMENTATION ON FIXATION STRENGTH OF ILIAC SCREW

作　　者：于滨生[1] 李泽民[1] 郑召民[1] 周治宇[1] 梁春祥[1] 李浩淼[1] 韩国伟[1] 

机构地区：[1]中山大学附属第一医院脊柱外科骨科研究所,广州510700

出　　处：《中国修复重建外科杂志》2010年第12期1455-1458,共4页Chinese Journal of Reparative and Reconstructive Surgery

基　　金：广东省科技计划资助项目(2008B050100012)~~

摘　　要：目的比较使用和未使用聚甲基丙烯酸甲酯(polymethylmethacrylate,PMMA)钉道强化髂骨上钉和下钉在疲劳载荷后的最大拔出力,为合理使用髂骨钉技术提供实验依据。方法从5具自愿捐献的成人防腐尸体采集10个完整髂骨标本用于实验。采用双能X线吸收法测定每具尸体L1～4椎体的骨密度(bone mineral density,BMD)。将植入髂骨上柱和下柱的螺钉分别命名为髂骨上钉和髂骨下钉。使用长70mm、直径7.5mm的螺钉,根据PMMA强化与否依次建立以下4组髂骨钉固定模型:髂骨上钉(A组)、PMMA钉道强化髂骨上钉(B组)、髂骨下钉(C组)和PMMA钉道强化髂骨下钉(D组)。将髂骨模拟人体站立位固定于MTS材料实验机上,向螺钉尾部施加100～300N循环压力载荷2000次后,测试髂骨钉的轴向最大拔出力。结果 5具尸体的BMD为(0.88±0.06)g/cm2。所有髂骨钉均准确植入预计钉道,未见髂骨钉穿入髋臼和穿出内外板等情况,疲劳测试后均未出现螺钉松动迹象。A、B、C、D组的最大拔出力分别为(964±250)、(1462±266)、(1537±279)、(1964±422)N。D组最大拔出力大于其他3组,差异均有统计学意义(P<0.05);B、C组最大拔出力明显高于A组,差异有统计学意义(P<0.05),B、C组间比较差异无统计学意义(P>0.05)。结论髂骨下钉的固定强度显著高于髂骨上钉;PMMA钉道强化技术可有效提高髂骨钉的锚定强度,可用于髂骨钉松动的翻修。Objective To compare the maximum pull-out strength of the upper iliac screw and lower iliac screw with and without polymethylmethacrylate （PMMA） augmentation, and to provide the experimental evidences for the rational use of iliac screws. Methods Ten intact human ilium from 5 donated cadavers with formalin embalmed were selected. The bone mineral density （BMD） of L1-4 of each cadaver was measured with a dual energy X-ray absorptiometry. The screws placed in the upper and lower iliac column were named as the upper and lower iliac screw, respectively. Using 70 mm length and 7.5 mm diameter screws with and without PMMA augmentation, 4 iliac screw technique models were sequentially established and tested as follows： upper iliac screw （group A）, upper iliac screw with PMMA augmentation （group B）, lower iliac screw （group C）, and lower iliac screw with PMMA augmentation （group D）. Each ilium was mounted on a material testing machine with its position similar to standing. Under 2 000 cyclic compressive loadings of 100-300 N to the screw, the maximum pull-out strength of iliac screw was measured. Results The BMD value of the 5 human cadavers was （0.88 ± 0.06） g/cm2. All the iliac screws were inserted into the screw tracts accurately as expected. No screw penetrations of acetabulum or cortex was not observed through visual inspection. There was no ＂halo＂ ring sign surrounding any screw after the 2 000 cycle loading. The maximum pull-out strengths of groups A, B, C, and D were （964 ± 250）, （1 462 ± 266）, （1 537 ± 279）, and （1 964 ± 422） N, respectively. Group D exhibited the highest maximum pull-out strength among the 4 groups （P 0.05）. No significant difference was detected between groups B and C （P 0.05）; however, groups B, C showed higher maximum pull-out strength than group A （P 0.05）. Conclusion The lower iliac screw offers significantly higher fixation strength than the upper iliac screw; PMMA augmentation could effectively increase the fixation stren

关 键 词：腰髂重建 髂骨钉 内固定 翻修 聚甲基丙烯酸甲酯 生物力学 

分 类 号：R687.3[医药卫生—骨科学]