RESUMEN
Objective To establish a set of digital robot-aided surgery system to represent the real surgery process, and realize robot control and force feedback in virtual environment by digital human tissue simulation combined with outer force feedback instrument. Methods The digital robot aided-surgery system design includes human tissue biomechanical modeling, biomechanical model calculation, force feedback instrument design, control algorithm, digital robot-aided surgery system based on biomechanical information. Results After local area network was successfully connected between haptic device control system and virtual environment, the system completed closed-loop information transfer process. Conclusions The robot-aided surgery system can realize the master-slave control, visual feedback and force feedback in virtual environment, which will contribute to the development of digital surgery simulation technology and gain advantages in the aspects of improving surgery success rate and training new doctors.
RESUMEN
Objective To make a reasonable selection from internal fixation Methods for treating femoral neck fracture, namely the fixation angle of a single screw, the number of screws and the combination mode of screws, so as to obtain the optimal stability of fracture reduction. Methods Based on the DICOM data and Lindon mode, a three-dimensional finite element model of femoral neck fracture fixation was built including different angles, numbers and combination modes of the screws. The model was attributed to nonlinear material properties based on the relationship between the property parameters of bone materials and the gray value of CT images, and loaded under the simulation of physiological loads. Results Corresponding to different angles of the fracture surface, the optimal fixation angle of the single screw was 65°and 70°in clinic. The more the number of screws, the better the effect of fixation, when the surgical condition was permitted. The inverted triangle placement was better than the triangle placement in case of three-screw fixation, while the triangle placement was superior to two-screw fixation, but the decision on the placement of two-screw fixation in flat form or diagonal form depended on the angle of the fracture surface. Conclusions Different angles of the fracture surface have significant impacts on the effect of fixation, and the loading simulation process on the three-dimensional model can provide a feasible way to the study of the fixation for the femoral neck fracture.