Modelling and Simulation of Energy Cutting Tool for Soft Tissue Using a Novel extended Finite Element Method

Background: Energy-based cutting tools combine cutting and haemostasis, making them widely utilised. Accurately predicting tissue deformation during energy-based cutting can provide precise navigation information to enhance surgical outcomes, while existing surgical cutting models focussing on blades-based tools are unable to accurately predict energy cutting deformation. Methods: This paper aims to propose a novel energy cutting model under different cutting trajectories. First, a stratified discontinuity mechanism-based modelling method of energy cutting is proposed. Second, a parameterised impact zone model is developed for describing complex surgical manipulations using intraoperative trajectories. Third, an incremental cutting computation algorithm and a novel void enrichment function are proposed to enhance the computational efficiency. Results: The mean absolute deformation errors of numerical and experimental results under various of cutting trajectories are less than 1 mm. The computation efficiency and convergence are also validated. Conclusions: The desired cutting deformation accuracy is achieved robustly while maintaining computation efficiency.