title: The effect of ergonomic laparoscopic tool handle design on performance and efficiency.
abstract: BACKGROUND
  Many factors can affect a surgeon's performance in the operating room; these may include surgeon comfort, ergonomics of tool handle design, and fatigue. A laparoscopic tool handle designed with ergonomic considerations (pistol grip) was tested against a current market tool with a traditional pinch grip handle. The goal of this study is to quantify the impact ergonomic design considerations which have on surgeon performance. We hypothesized that there will be measurable differences between the efficiency while performing FLS surgical trainer tasks when using both tool handle designs in three categories: time to completion, technical skill, and subjective user ratings.
  
  
  METHODS
  The pistol grip incorporates an ergonomic interface intended to reduce contact stress points on the hand and fingers, promote a more neutral operating wrist posture, and reduce hand tremor and fatigue. The traditional pinch grip is a laparoscopic tool developed by Stryker Inc. widely used during minimal invasive surgery. Twenty-three (13 M, 10 F) participants with no existing upper extremity musculoskeletal disorders or experience performing laparoscopic procedures were selected to perform in this study. During a training session prior to testing, participants performed practice trials in a SAGES FLS trainer with both tools. During data collection, participants performed three evaluation tasks using both handle designs (order was randomized, and each trial completed three times). The tasks consisted of FLS peg transfer, cutting, and suturing tasks.
  
  
  RESULTS
  Feedback from test participants indicated that they significantly preferred the ergonomic pistol grip in every category (p < 0.05); most notably, participants experienced greater degrees of discomfort in their hands after using the pinch grip tool. Furthermore, participants completed cutting and peg transfer tasks in a shorter time duration (p < 0.05) with the pistol grip than with the pinch grip design; there was no significant difference between completion times for the suturing task. Finally, there was no significant interaction between tool type and errors made during trials.
  
  
  CONCLUSIONS
  There was a significant preference for as well as lower pain experienced during use of the pistol grip tool as seen from the survey feedback. Both evaluation tasks (cutting and peg transfer) were also completed significantly faster with the pistol grip tool. Finally, due to the high degree of variability in the error data, it was not possible to draw any meaningful conclusions about the effect of tool design on the number or degree of errors made.
authors.affiliation: Mechanical Engineering Department, University of Utah, Salt Lake City, USA, kryztophert@gmail.com.
authors.forename: Kryztopher D
authors.initials: KD
authors.lastname: Tung
authors.forename: Rami M
authors.initials: RM
authors.lastname: Shorti
authors.forename: Earl C
authors.initials: EC
authors.lastname: Downey
authors.forename: Donald S
authors.initials: DS
authors.lastname: Bloswick
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Merryweather
mesh_terms: D000328:Adult; D004867:Equipment Design; D006804:Ergonomics; D005260:Female; D006225:Hand / Q000502:physiology*; D006801:Humans; D020706:Laparoscopes / Q000592:standards*; D010535:Laparoscopy / Q000295:instrumentation*; D008297:Male; D012016:Reference Values