锁骨骨折三种内固定方法的生物力学性能比较

目的　探讨新研制的防滑锁骨钉在锁骨骨折内固定中的生物力学性能 ,并与传统的 4孔钢板和克氏针内固定方法进行比较 ,为临床应用提供科学依据。方法　采集 9具成人新鲜锁骨标本 ,行中外 1/ 3处锁骨骨折模型 ,分别采用防滑锁骨钉 (PSCN) ,4孔钢板 (4SP)和克氏针 (KP)三种内固定方法固定 ,运用实验应力分析手段测试各组试件的生物力学特性 ,并进行比较。另设正常锁骨标本组以作对照。结果　 (1)三点弯曲强度测量 ,4SP和PSCN组均接近正常标本 (P >0 0 5 ) ,而KP组与正常标本组相差显著 (P <0 0 5 ) ;弯曲刚度测量结果具有相似的规律性。(2 )扭转强度和刚度测量表明 ,4SP和PSCN与正常标本无显著性差异 ,而比KP固定来得优越 (P <0 0 5 )。 (3)拉伸试验表明 ,4SP和PSCN内固定抗拉强度和刚度优于KP内固定 (P <0 0 5 ) ;抗拔力PSCN明显优于KP内固定 (P <0 0 5 )。 (4 )PSCN内固定应力遮挡小 ,明显优于 4SP(P <0 0 5 )。结论　PSCN在强度和刚度上均明显优于KP内固定 ,与 4SP相接近 ,且应力遮挡小 ,是当前锁骨内固定的理想固定方法

A Biomechanical Study of a New Fracture Clavicle Internal-Fixator and Compared with Three Instruments

Objective To study the biomechanical characteristics of a new preventslide clavicular nail for treatment of clavicular fracture. This study was made to provide some biomechanical evidences for better clinical operation. Methods 9 adult clavicles were divided into 3 groups randomly, and made a model for the middle and lateral fractures. Those 3 groups was fixed with prevent-slide clavicular nail(PSCN), 4 holes steel plate(4SP) or kirschner's pin(KP), respectively. The biomechanical test was performed and the stress was analyzed. Results (1)Bending strength of internal fixation with 4SP and PSCN were close to normal specimen group(NS) (P>0.05);but KP group was less than normal specimen group (P<0.05).(2) Torsional strength and stiffness of internal fixation with 4SP and PSCN were less than NS group,but more than KP group (P<0.05).(3) Anti-putout strength and stiffness of internal fixation 4SP and PSCN were larger than KP group (P<0.05); Anti-putout power of internal fixation with PSCN were larger than KP group (P<0.05).(4) Stress shielding of internal fixation with PSCP were less than 4SP group (P<0.05). Conclusion The strength and stiffness of PSCN was larger than that of KP,and was close to 4SP.The stress shielding of PSCN was the less.The internal fixation with PSCN is an ideal method for treating clavicular fracture.