Hands-on robot-assisted fracture reduction system guided by a linear guidance constraints controller using a pre-operatively planned goal pose

Background In robot-assisted fracture reduction systems, the fine alignment of the fractured bone and its path planning are still of issues that need to be resolved. Methods A novel linear guidance constraints (LGC) controller guides a robot along the shortest path to align a distal fracture segment and a proximal one. In addition, the surgeon can modify the path whenever s/he wants. Results When the LGC controller is used in the experiment on a femoral bone model with simulated muscles, the fracture reduction time was measured to be 35.6 +/- 16.4 seconds, while the position and the angle errors were 0.41 +/- 0.61 mm, and 0.22 +/- 0.80 degrees, respectively. The proposed controller reduced the reduction time by 78.1%, the translational error by 91.6%, and the angular error by 95.4%, compared with the cases without the LGC controller. Conclusions It was proven that the proposed scheme reduced the reduction time and the pose error of the fracture alignment, and that it is effective to alleviate the maneuvering load.