Evaluating a Solely Mechanical Articulating Laparoscopic Device: A Prospective Randomized Crossover Study

Background: The FlexDex (FD) is a solely mechanical articulating device that combines the functionality of robotic surgery with the relative low cost and simplicity of laparoscopy. We sought to evaluate the performance of first-time FD users while performing a simple suture task at locations of varying degrees of difficulty.

Study Design: A prospective, randomized crossover study was performed comparing the FD to standard laparoscopy (SL). Two specific groups were evaluated; Group 1 consisted of complete novices, and Group 2 consisted of surgical trainees. Participants performed a simple suture with both FD and SL locations of varying degrees of difficulty (Easy, Moderate, and Hard). The following outcomes were evaluated: Instrument Function and Ergonomics (Comfort/Ergonomics survey), Task Difficulty (National Aeronautics and Space Administration Task Load Index [NASA-TLX]), Task Performance Quality (Objective Structured Assessment of Technical Skills [OSATS]), and Time (seconds).

Results: Twenty-two participants were enrolled with 12 participants in Group 1 and 10 participants in Group 2. Group 1-FD participants experienced overall less shoulder strain (1.2 ± 0.40 versus 1.9 ± 0.90, P = .01), and Group 2-FD participants experienced less shoulder (2.5 ± 0.66 versus 4.0 ± 0.50, P = .01), back (1.1 ± 0.32 versus 1.9 ± 0.74, P = .01), and forearm strain (1.9 ± 0.88 versus 2.5 ± 1.1, P = .04). Group 1 participants using the FD experienced higher mental demand (73 ± 17 versus 48 ± 27, P < .01) and perceived effort (70 ± 20 versus 54 ± 23, P < .001). Both Group 1 and Group 2 FD participants performed tasks at the Hard location more effectively. Both Group 1 (70 versus 87, P = .21) and Group 2 (53 versus 60, P = .55) performed tasks at the Hard location in similar times, while Group 1 (80 versus 177, P = .03) and Group 2 (33 versus 70, P = .001) performed tasks at the Easy location in shorter times using SL.

Conclusions: This study demonstrates the first assessment of the FD, a mechanically articulating laparoscopic tool. First-time FD users demonstrated improved ergonomics and effectiveness suturing at difficult locations. Future studies will focus on comparison to robotic surgery and translation into clinical applications.