Abstract：Based on CT scans, the C4-C5 cervical segment finite element model for 3 year old child was developed with accurate skeletal geometries and detailed anatomical structures of intervertebral disc. Grounded on biomechanical experiments published of adult cervical spine and the comparison of the data between adult and child, scaling methods were used to calculate the material parameters for 3 year old pediatric cervical spine. The model was validated under quasistatic and dynamic tensile, quasistatic flexion extension, and lateral bending as well as axialrotation loadings. It is indicated that responses for the tensile simulations are consistent with those of the experiments, with the quasi static tensile stiffness of 211.8 N/mm, dynamic tensile ultimate failure force of 759.9 N and ultimate failure displacement of 5.08 mm in simulations. Responses for quasi static bending simulations were within the standard deviation or corridor of the experiments, with the range of motion for extension 9.75°, flexion 9.29°, lateral bending 3.79°and axial rotation 7.04°. It is indicated that this model is biofidelic enough to reflect the biomechanical properties of 3 year old pediatric C4-C5 cervical spine under quasi static and dynamic tensile, as well as quasistatic flexion extension, lateral bending and axial rotation loadings.
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