Fig 1.
The computational model used in this study consisted of the spinal cord, partitioned into its constituent tissues, the dura and pia maters, the vertebral bodies and the cerebrospinal fluid.
Table 1.
Material models used in this study.
Fig 2.
Variability in biomechanics and tissue sparing caused by morphology.
Incorporating morphological variability into this computational model showed that the model is sensitive to changes in geometry, resulting in variability in the biomechanical outcomes including the forces (A), peak force (B), and tissue sparing (C).
Fig 3.
Correlation matrix between morphology and biomechanical measures.
A heat map of the correlation matrix showing the linear relationship between the morphological and biomechanical measures. Pearson correlation coefficients are shown, with positive correlations shown in red and negative correlations shown in blue. A higher correlation coefficient is indicated by darker shades in both directions (red and blue). Morphology measures include the spinal cord diameters (SCOW and SCOD), spinal canal diameters (SCW and SCD), the thickness of the cerebrospinal fluid in the mediolateral (CSF ML) and anterior-posterior axes (CSF AP), and the transverse area of the spinal cord (SCO) and spinal canal (SC).
Fig 4.
Impact of mediolateral geometry on spinal cord-impactor interaction.
The mediolateral geometry of the spinal cord influences alters how it engages with the impactor. Increased CSF surrounding the spinal cord allowed the cord to move laterally during impact and reduced the forces applied to the spinal cord (S14), while a high spinal occlusion resulted in more tissue being engaged under the impactor and a higher peak force (S28).
Fig 5.
Subject-specific tissue-level biomechanics under the same loading.
Applying the same impact protocol to each subject generated different tissue-level strains in each subject, as indicated by the minimum principal logarithmic strain (LE). In both the gray and white matter, the dark red area marks regions that exceed injury threshold levels and are predicted to become damaged.