Comparison between guide plate navigation and virtual fixtures in robot-assisted osteotomy.

To verify the advantages of Virtual Fixtures (VFs) by comparing the result of guide plate navigation (GPN) and VFs in robot-assisted osteotomy. Robot-assisted surgery has been extensively applied in traditional orthopedic surgeries. It fundamentally improves surgeries' cutting accuracy. In addition, many key techniques have been applied in bone cutting to increase the procedure's safety in various ways. In this paper, two robot-assisted osteotomy methods are proposed. Three operators with no osteotomy experience performed plane cutting with the assistance of a robot. GPN and VFs were applied to assist the Sawbones cutting. Each operator has five attempts using each method to perform bone cutting, distance errors and angular errors were recorded. The advantage of Sawbones is that there is no influence from soft tissues and blood. It can give a more precise measurement. The results show that both methods have high accuracy with the robot's assistance. VFs have higher accuracy in comparison with GPN. With GPN, the mean distance and angular error of the three operators were 2.974 ± 0.282 mm and 4.737 ± 0.254°. With VFs, the mean range and angular error of the three operators were 1.857 ± 0.349 mm and 2.24 ± 0.123°, respectively. VFs limited the robot's end in the planned area, increasing the accuracy and safety of robot-assisted osteotomy.