The trade-off between flexibility and maneuverability: task performance with articulating laparoscopic instruments

Minimally Invasive Surgery Program, Legacy Health System, 1040 NW 22nd Avenue, Suite 560, Portland, OR 97210, USA.
Surgical Endoscopy (Impact Factor: 3.26). 04/2009; 23(12):2697-701. DOI: 10.1007/s00464-009-0462-y
Source: PubMed


Laparoscopic instruments are rigid and thus cannot provide the degrees of freedom (DOF) needed by a surgeon in certain situations. A new generation of laparoscopic instruments with the ability to articulate their end effectors is available. Although these instruments offer the flexibility needed to perform complex tasks in a constricted surgical site, their control may be hampered by their increased complexity.
This study compared the task performance between articulating and conventional laparoscopic instruments. Surgeons with extensive laparoscopic experience (8 experts) and staff with no surgical experience (8 novices) were recruited for the test. Both groups were required to perform three standardized tasks (peg transfer, left-to-right suturing, and up-and-down suturing) in a bench top model using conventional and articulating instruments. Performance was scored using a standardized 100-point scale based on movement speed and accuracy. After the initial trials with conventional and articulating instruments, each participant was given a short orientation on how to use the articulating instrument advantageously. The participant then was retested with the articulating instrument.
As expected, the expert group scored significantly better than the novice group (p < 0.001). The combined data from both groups showed better performance with the conventional instruments than with the articulating instruments (p = 0.074). The experts maintained their proficient laparoscopic performance using conventional instruments in their first attempts with the articulating instruments (91 vs. 84), whereas the novices had greater difficulty with the articulating instruments than with the conventional instruments (46 vs. 59). After a short orientation, however, the novices outscored the expert group in terms of net improvement in performance with the articulating instrument (27 vs. 1% improvement).
Experienced surgeons are readily able to transfer their skills from conventional to articulating laparoscopic instruments. To speed the learning process, the use of articulating instruments can be started at an early stage of surgical training.

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Available from: Bin Zheng, Mar 31, 2014
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    • "Moreover, it is difficult to perform technically demanding maneuvers, e.g., intracorporeal suturing and knot tying [3, 4]. To overcome the restriction in movements, various steerable instruments (also known as deflectable, rotatable, or articulated instruments) have been developed [5–9]. The advantage of these instruments compared with the conventional ones is that they provide sideways rotations of the tip. "
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