Real-Time Haptic-Based Soft Body Suturing in Virtual Open Surgery Simulations

In this work, we present a real-time virtual reality-based open surgery simulator that enables realistic soft-tissue suturing with bimanual haptic feedback. Our system uses eXtended Position-Based Dynamics (XPBD) for soft body and suture thread simulation, allowing stable real-time physics for complex interactions like continuous sutures and knot tying. In tests with all four common suturing techniques, purse-string, Connell, stay, and Lembert, the simulator maintained high frame rates (50-80 FPS) with up to 4,155 simulated particles, demonstrating consistent real-time performance. As part of our work, we conducted a user study using our suturing simulator, where 24 surgical trainees and experts used the Virtual Colorectal Surgery Trainer - Rectal Prolapse simulator. The user study showed that 71% of participants (n=17) rated the anatomical realism as moderate to very high. Half (n=12) found the force feedback realistic, and 54% (n=13) participants found the force feedback useful, indicating effective immersion while also highlighting the need for improved haptic fidelity. Overall, the simulation provides a low-cost, high-fidelity training platform for open surgical suturing, addressing a critical gap in current virtual reality educational tools.