Ergonomic evaluation of a new handle for laparoscopic dissector based on upper extremity posture

Abstract

Extreme motions of upper extremity during laparoscopic surgery have been one of the most important risk factors that cause work-related musculoskeletal disorders among surgeons. This study presents a new pistol-type handle (NPT) for laparoscopic dissector. The new handle provides ergonomic support for the thumb and purlicue to make it more flexibly and steadily to open and close end-effector. Other two commercial handles, including a pistol-type (PT) and a ring-type (RT), were compared together using objective and subjective studies. Twenty surgical students with clinical experience performed simulation tasks of dissection and precision handling. Subjects’ motions (wrist, forearm and upper arm) and performance were measured by inertial measurement unit (IMU) and video analysis, with opinions and perceptions evaluated by questionnaires. The outstanding goniometry results reveal that completing dissection task using NPT reduces the mean angle deviations relative to comfortable upper extremity position. The performance shows no difference between NPT and PT, however, NPT and PT perform less task errors and less task time than RT. The subjective results show that NPT significantly obtains preferences and reduces the degree of task difficulty. For performance on task completion, pistol-type handles show better usability than ring-type. For comfortable upper extremity posture, NPT has been demonstrated goniometry and ergonomic advantages during operations. The handle with thumb and purlicue support can protect surgeons’ musculoskeletal health by means of reducing awkward wrist postures and exaggerated arm arcing movements.