Development of a biofidelic human spine model for vibration characterization

Vibration is a physical phenomenon that occurs when objects or systems move back and forth rapidly. Millions of people worldwide are affected by vibration-related health issues every year. However, prolonged exposure to vibration can have serious health implications, including back pain, muscle strain, and damage to nerves and blood vessels. While computational modelling studies and tests on dummies have been performed, these do not accurately simulate the structural and material components of the spine, leading to less accurate results. Therefore, this study attempted to develop a biofidelic spine model using 3D printing technology and based on the THUMS Dummy model (AM50 V 4.02 Pedestrian) that closely simulates a real human spine structure. This developed model was used to perform the experiment exposed to vertical sinusoidal vibrations under different magnitudes (1.1 m/s², 0.75 m/s², and 0.4 m/s²) in the frequency range of 1-20 Hz. The collected data sets were analyzed to study the effect of vertical sinusoidal vibration magnitude and obtain the L₅ to C₁ transmissibility curves across a specified frequency range. The transmissibility curve was further analyzed to appraise the biofidelity of the developed human spine model and compare it to the literature. The results depicted that the two resonance peaks were observed between 2 and 3.5 Hz and 4-6 Hz at magnitude 1.1 m/s² and 0.75 m/s², respectively, and the multiple resonance peaks were observed at the magnitude of 0.4 m/s². The comparison between experimental data sets and biofidelic model responses indicates that the developed model is feasible for simulating vertical sinusoidal vibration-based effects on the human spine.