Research and development of virtual surgery simulation system with haptic feedback for personalized TKA

Physicians educated with traditional surgical training modes cannot meet the current surge in demand for knee joint patients. The aim of this work is to develop a simulation system based on virtual reality technology for the personalized knee replacement surgery. The virtual geometric models of knee joint and instruments were established by 3D reconstruction and CAD modeling technology respectively. We studied the voxelization algorithm and applied it to generate the virtual physical models. By using coordinate match method, the force model of the instrument was established between the device interface and the proxy. The AABB bounding box hierarchy tree was used as the collision detection model, we applied the overlapped intersect way to simulate deformation of tissue and the single point constraint force rendering to simulate the operation process. By setting up the hardware platform consisting of Phantom Omni and computer, and configuring the software environment CHAI 3D and OpenGL, the virtual knee replacement surgery simulation system was constructed. We compared the training time of the actual surgical operation of the professionals who experienced system with that of the control group, and used a questionnaire survey to make assessment of the system. Results showed that the system achieved the simulation of tissue deformation and force haptic feedback of drilling and osteotomy along the planned path in TKA, and the real-time performance of the system was excellent, the visual and haptic update frequency was maintained at 60 Hz and 1000 Hz respectively. The statistical results illustrated that there was a statistically significant difference (P = 0.04) in the actual operation time between the two groups, the questionnaire results were all above the average excellent level (P < 0.05). The constructed simulation system provides a safe, reliable and effective mode for medical training and preoperative drilling of TKA.