Simple incision and suture modeling on fixed structured grids

This paper presents a simple yet versatile approach to simulate skin incisions and suturing using nonlinear finite element analysis on a fixed structured grid with a spring-based suture model. Incisions and wounds are introduced by element removal and the sutures are discretely modeled by applying linear constraint relations pairwise to groups of nodes. Two numerical examples utilize the closing of an elliptical wound to study the influence of the number of sutures and their location, and two test cases use the Z-plasty transposition flap technique to investigate the versatility of the proposed method and for comparison with state-of-the-art results. The results indicate that the presented method is able to recreate literature results to an acceptable level of accuracy. Further, the method proves versatile due to the ability to freely introduce incisions and wounds onto the fixed grid modeling domain without remeshing. Lastly, the two main advantages of the discrete suture representation are the ability to capture local stress concentrations near the sutures and the full freedom in placing the sutures.