Towards improving the accuracy of musculoskeletal simulation of dynamic three-dimensional spine rotations with optimizing model and algorithm

•Model complexity and optimization criteria significantly affect spinal simulations.•A dedicated musculoskeletal simulation framework of the spine is presented.•Passive forces from spinal joints and muscles increase simulation accuracy.•Different optimization criteria behave distinctly for different spinal motions.•Generally minimizing the sum of squared muscle activations outperforms the others.