Biomechanical comparison of CRIF and reconstruction plate for stabilization of distal femur fractures in dogs

ABSTRACT This study aims to compare the biomechanical properties, through compression eccentric test, of the resistance of the 5.0mm Clamp and Rod Internal Fixation Implants (CRIF) and 3.5mm reconstruction plate in fixing dog femur distal fracture. It was used 22 femurs from 11 dog cadavers with age between 2 and 7 years old and body weight between 20 and 40kg, subdivided into two groups, called CRIF Group (CG - 11 femurs) and plate group (PG - 11 femurs). A distal fracture in the specimens with a gap of 0.5cm osteotomy, was simulated to perform the test, performed by the oscillating saw, just proximal to the beginning of the trochlea. The implants were fixed by the standards AO / SIF, laterally to the femur, using three distal screws and five proximal to the fracture site. PMI computer program was used to calculate the maximum point of resistance before failure and evaluated the variables maximum strength, real maximum deformation, stiffness, intermediate strength and real intermediate deformation. No statistically significant differences were found between the GC and GP as the variables evaluated, suggesting that both implants are good fixation options for such fractures.

摘要 本研究旨在通过偏心压缩试验，对比5.0mm夹杆式内固定植入物（Clamp and Rod Internal Fixation Implants，CRIF）与3.5mm重建钢板在固定犬股骨远端骨折时的抗载荷生物力学性能。本研究选取11只年龄2~7岁、体重20~40kg的犬尸体的22个股骨标本，分为两组：CRIF组（CG，11个股骨）与钢板组（PG，11个股骨）。通过摆锯于股骨滑车起始端稍近端位置截骨，制造0.5cm的骨缺损间隙，以此模拟标本的远端骨折模型以开展试验。按照AO/SIF标准，于股骨外侧于骨折远端置入3枚螺钉、近端置入5枚螺钉以固定植入物。采用PMI计算机程序计算失效前的最大阻力点，并评估最大强度、实际最大变形、刚度、中间强度及实际中间变形等指标。经评估的各项指标中，CG组与PG组均未发现统计学显著差异，提示两种植入物均为该类骨折的优质固定方案。