Path planning for fracture reduction robots incorporating physiological tissue response and safety-oriented...

Robot-assisted orthopedic reduction faces the dual challenge of achieving geometric precision while preserving physiological safety. This study presents a physiology-driven, multi-objective path-planning framework to optimize both surgical efficiency and tissue protection.

A three-zone monitoring system-Doctor-Control, Bone-Response, and Tissue-Impact-was established in animal experiments to simultaneously record robotic kinematics, bone motion, and vascular-neural physiological signals. Correlation analyses identified strong coupling between mechanical motion and physiological responses, which guided the development of a multi-objective optimization framework combining Rapidly exploring Random Tree (RRT) and Non-dominated Sorting Genetic Algorithm II (NSGA-II). The planner minimized both geometric path length and physiological disturbance.

Significant relationships were observed between femur-tibia displacement and femoral (r = - 0.90, p = 0.033) and iliac (r = 0.89, p = 0.033) artery flow. Tibial and distal femur rotations markedly reduced sciatic nerve conduction amplitude ( $r\approx -0.9$ ). In representative reduction scenarios, the proposed method achieved 5-15% shorter trajectories and 50-70% lower disturbance loads compared with ERRT* and MO-ERRT*.

The physiology-driven optimization framework enables safe and efficient robotic fracture reduction by integrating multi-modal physiological feedback into path planning. These results demonstrate its potential for intelligent, safety-aware surgical robotics.