Virtual Pelvic Surgery Simulator For The Prevention Of Surgical Errors

A thesis in Mechanical Engineering, MD ARIFUZZAMAN ARIF



Recent data suggests that over 200 million surgeries are performed annually worldwide and about 3 to 22% of these surgeries involve some sort of complications. Surgical errors can be caused by both technical errors and cognitive errors which may happen to even an experienced surgeon. Resident surgeons are more prone to surgical errors as they start their surgical career with less experience and skills. In order to quantify the surgical errors and accelerate the learning experience of surgeons, a novel method has been proposed that can identify, model and describe surgical errors by using biomechanical motion analysis and a high-fidelity 3-D surgery simulator. This analysis has been done for a complex, common and high-risk surgery, the midurethral sling (MUS) procedure for stress urinary incontinence. The experimental protocol allowed for monitoring of the surgeon’s full body kinematics during the procedure and accurate tracking of the trocar inside the body. Surgeon kinematics and position of the trocar relative to anatomical structures were tracked for both successful (continuous contact with the pubis) and error trials (lateral deviation and cephalad deviation). The kinematics of the wrist, elbow, and shoulder joints demonstrate major differences between the three different passage conditions. Cephalad deviation of the trocar entered the perito iv remains within the anterior side of the pelvic bone without making any contact with the external iliac vein. Off plane rotations of the shoulder, elbow and wrist joints, i.e. abduction-adduction, and internal-external rotations, incurred large errors due to the marker set used in the experiment. The model demonstrated good fidelity except for gel thickness and transparency. Based on the expert surgeon, the physical model replicated the feeling of performing the procedure on a live subject. Differences in the elbow, wrist and shoulder joint kinematics between the three different passage conditions indicate that it is possible to identify errors based on kinematics. Since the kinematics between the different trials seem to be different, there is potential in training novice surgeons on proper kinematics to ensure successful passages of the trocar.