An expandable rigid PU foam can turns into complex shapes, with a shell like structure on the outside and honeycomb structure on the inside, which can be easily shaped to a vertebra form. The present study aims to determine whether expandable rigid polyurethane foam was an appropriate substitute for rigid block polyurethane foam to model the trabecular bone. Static compression tests were performed to determine compressive moduli and yield stresses on three polyurethane foam densities namely 0.16 g/cm³, 0.24 g/cm³ and 0.42 g/cm³. Morphology of the PU foams for all densities was also observed. The compressive modulus for 0.16 g/cm³ and 0.24 g/cm³ were found varied from 40 to 43 MPa and 83 to 92 MPa while yield stress ranged from 2.1 to 2.3 MPa and 3.4 to 4.8 MPa respectively. As for 0.42 g/cm³, the compressive modulus and yield stress varied from 240 to 256 MPa and 38 to 40 MPa. Based on these results, the compressive modulus and yield stress of 0.24 g/cm³ compared favourably with rigid block PU foam and human cadavers presented in the literatures. Hence, the findings of this study could potentially be used in developing a synthetic vertebral trabecular bone of paediatric spine for biomechanical testing.

可膨胀的硬质PU泡沫可以变成复杂的形状，外部具有壳状结构，内部具有蜂窝状结构，可以很容易地成型为椎骨形状。本研究旨在确定可膨胀硬质聚氨酯泡沫塑料是否可以替代硬质嵌段聚氨酯泡沫塑料来模拟小梁骨。静态压缩测试以确定在三个聚氨酯泡沫的密度即0.16克/厘米的压缩模量和屈服应力³，0.24克/厘米³和0.42克/厘米³。还观察到所有密度的PU泡沫的形态。0.16 g / cm ³和0.24 g / cm ³的压缩模量发现屈服应力分别为40至43 MPa和83至92 MPa，而屈服应力分别为2.1至2.3 MPa和3.4至4.8 MPa。对于0.42g / cm ³，其压缩模量和屈服应力在240至256MPa和38至40MPa之间变化。基于这些结果，压缩模量和屈服应力为0.24 g / cm ^3，与文献中提出的刚性块状PU泡沫和人体尸体相比具有优势。因此，这项研究的发现可能潜在地用于开发小儿脊柱的合成椎骨小梁骨以进行生物力学测试。