Laparoscopic surgery (LS) has been shown to provide great benefits to patients compared with open surgery. However, surgeons experience discomfort, low-efficiency, and even musculoskeletal disorders (MSDs) because of the poor ergonomic design of laparoscopic instruments. A methodology for the ergonomic design of laparoscopic dissector handles considering three-dimensional (3D) hand anthropometry and dynamic hand positions was addressed in this research. Two types of hand positions for grasping and stretching were scanned from 21 volunteers using a high-resolution 3D scanner. The 3D anthropometric data were extracted from these 3D hand pose models and used to design an improved handle (IH) that provides additional support for the thumb, a better fit to the purlicue, and a more flexible grasp for the index finger. Thirty subjects were invited to evaluate the IH in terms of muscular effort, goniometric study of motion, and efficiency and effectiveness during four trials of a laparoscopic training task. Questionnaires provided subjective parameters for ergonomic assessment. Positive results included less muscle load in the trapezius as well as significant but small angular differences in the upper limb. No significant reduction in the trial time and no increased percentage of the achievement were observed between the IH and the commercial handle (CH). Improved intuitiveness, comfort, precision, stability, and overall satisfaction were reported. IH provides significant ergonomic advantages in laparoscopic training tasks, demonstrating that the proposed methodology based on 3D anthropometry is a powerful tool for the handle design of laparoscopic dissectors and other surgical instruments.

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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.

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