Building upon the Vasavada 1998, and more recent Mortensen 2018, neck and head model, we are exploring the role of muscles and passive cervical spine (neck) soft tissue in stabilizing the head and neck following impact loads. We have collected human subject head kinematics data undergoing mild external loads with varying load direction (resulting in head extension or head lateral flexion) and varying muscle activity (minimal activation/relaxed and maximal activation/co-contracted). Example videos of the experimental procedures:





We have developed subject-specific head and neck models and validated them against measured head kinematics using measured impact loads. The head and neck model adds cervical spine ligaments, which utilize a new dynamic ligament plugin model. The dynamic ligament model is similar to the current ligament model available in vanilla OpenSim, but adds velocity dependence based on previous experimental literature. Using simulations of our experimental impacts, we can now predict the torque contributions of the various components of the cervical spine (active muscle, passive muscle, other passive structures). Example videos of OpenSim simulations validated against experimental results:









We are now obtaining consent to provide data publicly through SimTK. To be included are the baseline model, subject-scaled models, experimental average male and experimental average female models, relevant experimental data (head kinematics and impact loads), and relevant files for running simulations (muscle activations, setup files, external load files, output motion and analysis files).

For more information, please contact: calvin.kuo@ubc.ca

Relevant Citations:
1) Kuo C., Fanton M., Wu L., Camarillo D.B. "Spinal constraint modulates head instantaneous center of rotation and dictates head angular motion." Journal of Biomechanics. 76(25): 220-228. (2018)
2) Kuo C, Sheffels J, Fanton M, Yu I, Hamalainen R, Camarillo D. "Passive Cervical Spine Ligaments Provide Stability during Head Impacts." Journal of the Royal Society Interface. https://doi.org/10.1098/rsif.2019.0086 (2019)