RESUMEN
Objective To investigate the causes and preventive measures for deviation of guide needle in orthopedics robot surgery.Methods A robotic surgery was simulated on a wooden stick.The guide needle was inserted under the guidance of the robot.A lateral deviation force was applied respectively onto the tail and tip of the needle.The actual offset distance at the guide needle tip was measured and compared with the 1mm offset allowed by robot monitoring.Results The offset distance of the guide needle tip was 0,5+0.07 mm when the deviation force was applied onto the tail,significantly smaller than the 1 mm offset allowed by the robot monitoring(l=22.588,P<0.001).The offset distance of the guide needle tip was 4.92+0.16 mm when the deviation force was applied onto the tip,significantly larger than the 1 mm offset allowed by the robot monitoring(t=17.416,P<0.001).Conclusions The deviation of guide needle may be caused chiefly by the deviation force onto the tip.As the actual offset distance of the guide needle tip may be larger than that shown on the robot monitor in orthopedics robotic surgery,the intraoperative monitoring should serve only as a reference to the deviation of the guide needle.The operative details may be the key to prevention of such deviations.