Indirect visual guided fracture reduction robot based on external markers

Abstract

Background Traditional fracture reduction surgery cannot ensure the accuracy of the reduction while consuming the physical strength of the surgeon. Although monitoring the fracture reduction process through radiography can improve the accuracy of the reduction, it will bring radiation harm to both patients and surgeons. Methods We proposed a novel fracture reduction solution that parallel robot is used for fracture reduction surgery. The binocular camera indirectly obtains the position and posture of the fragment wrapped by the tissue by measuring the posture of the external markers. According to the clinical experience of fracture reduction, a path is designed for fracture reduction. Then using position‐based visual serving control the robot to fracture reduction surgery. The study is approved by the ethics committee of the Rehabilitation Hospital, National Research Center for Rehabilitation Technical Aids, Beijing, China. Results Ten virtual cases of fracture were used for fracture reduction experiments. The simulation and model bone experiments are designed respectively. In model bone experiments, the fragments are reduced without collision. The angulation error after the reduction of this method is 3.3° ± 1.8°, and the axial rotation error is 0.8° ± 0.3°, the transverse stagger error and the axial direction error after reduction is 2 ± 0.5 mm and 2.5 ± 1 mm. After the reduction surgery, the external fixator is used to assist the fixing, and the deformity will be completely corrected. Conclusions The solution can perform fracture reduction surgery with certain accuracy and effectively reduce the number of radiographic uses during surgery, and the collision between fragments is avoided during surgery.

Trajectory optimisation with musculoskeletal integration features for fracture reduction orthopaedic robot

“…Meanwhile, the feedback of the motor is realised through hexadecimal data for status monitoring. In addition, the stability and feasibility of the robot had been verified in previous experiments 3 …”

“…In addition, the stability and feasibility of the robot had been verified in previous experiments. 3…”

“… Mathematical model 3 : P i and B i ( i = 1, 2, 3,…, 6) represent the hook hinge centre; q i ( i = 1, 2, 3,…, 6) represents the vector of drive actuator …”

“…In order to ensure the human safety, the maximum speed of the trajectory is 4 mm/s and the maximum acceleration of the trajectory is 0.5 mm/s 2 . 3,18,33 Finally, the optimal trajectory considering the influence of muscle force was obtained.…”

“…Trajectory planning, as the basis of the movement of the fracture reduction orthopaedic robot, could guide the robot to exhibit given actions. Although clinician's manual fracture reduction technique has been verified effectively, 3 lower level of digitisation and inconsistent standards make it impossible for robot to imitate doctor's actions completely. Meanwhile, for parallel medical robot, research on the trajectory planning of moving platform 4 needs further explore, which is one of the key problems.…”