MIS instruments - An experimental comparison of various ergonomic handles and their design

Background: Various handles are available for use in minimally invasive sur gery. Nonergonomic positioning of the hand and fingers can lead to pressure areas, nerve irritation, and rapid fatigue. This study was designed to com pare the ergonomic efficiency of several different handles,along with the c oncepts underlying them, in an attempt to find the best one for laparoscopi c surgery. We also consider whether the position of the surgeon in relation to the patient and the posture of the surgeon have any influence on the us e of the handles. Method: A ring handle positioned in-line (the Microsurge/ Vygon 01-1007), a n axial handle (the Aesculap PM-953), a shank handle (the Wile 25.00), and a functional model of a new ergonomic multifunctional handle (the MFEHG Sch afreuter) were tested and evaluated by 15 volunteers during an objective te st using a transparent pelvitrainer with the left and right hand in a front al and left and right lateral positions. Our analysis was based on their su bjective answers to a questionnaire developed from ergonomic checklists and the semiquantitative observations of the test leader about their posture d uring testing. Results: There were no significant differences in the results of the object ive tests. Subjectively, the shank handle was preferred by most test person s, followed by the functional model for the right hand and the axial handle for the left hand; the ring handle positioned in-line scored poorly for bo th right and left hands. Arm movements were greater in the latter than in t he frontal position. Conclusions: A clear recommendation for any one of the three currently avai lable handles cannot be given. The results obtained with a simple model of a multifunctional handle were highly promising, and it may be possible to e xtend it to a real multifunctional instrument.