Introduction: This study compares the effects of surgical techniques (one-handed versus two-handed) and surgeon’s standing position (side-standing versus between-standing) during laparoscopic cholecystectomy (LC) and its outcomes on surgeons’ learning, performance, and ergonomics. There is little homogeneity in how to perform and train for LC. Variations in standing position (“American” or side-standing technique where the surgeon stands on the patient’s left versus “French” or between-standing technique where the surgeon stands between the patient’s legs) as well as hand technique (one-handed versus two-handed) exist. The two-handed technique refers to the surgeon providing his own exposure using one hand for dissection and the other for retraction while the assistant hold the camera. The one-handed technique refers to the situation during which the surgeon dissects with one hand and manages the camera with the other with the assistant helping in providing exposure and gallbladder retraction.
Methods: Thirty-two LC procedures performed by a total of eight subjects on a virtual reality simulator were video recorded and analyzed. All eight subjects were right-handed. Each subject performed four different procedures so as individual assessment of the following methods was possible: one-handed/side-standing, one-handed/between-standing, two-handed/side-standing, and two-handed/between-standing. Physical ergonomics were evaluated using the Rapid Upper Limb Assessment (RULA) tool. Mental workload assessment was achieved through the use of the National Aeronautics and Space Administration-Task Load Index (NASA-TLX). Performance evaluation data generated by both the virtual reality simulator and a subjective survey were also analyzed.
Results: The RULA scores for all procedures were statistically significantly better for the between-standing technique compared to the side-standing technique. Regardless whether the technique used was one- or two-handed, the between-standing technique was associated with better ergonomics than the side-standing technique. The median RULA scores for different anatomical area was significantly worse for the upper arms and trunk in the side-standing position (upper arms: 3.5 – trunk: 3.5) when compared with the between-standing position (upper arms: 2 and trunk: 1.5). This showed that the main disadvantage of the side-standing position to be its detrimental effect on both the upper arms and trunk. There was no significant difference in other body parts including the lower arms, wrist, neck and legs.
Using the NASA-TLX tool, the side-standing position was associated with statistically significantly higher effort, frustration, and physical demand (p< 0.05). The objective, simulator-generated performance metrics demonstrated no differences in either operative time or complication rate among the four methods for performing LC. Survey answers indicated the subjects’ choice to be the two-handed/between-standing technique as the best procedural method for teaching and standardization.
Conclusion: Laparoscopic cholecystectomy poses a risk of physical injury to the surgeon. As it is currently commonly performed in the United States, the left side-standing position leads to increased physical demand and effort, thus resulting in ergonomically unsound operative conditions. Until further investigations are made, adopting the between-standing position deserves serious consideration as it presents the best short-term ergonomic alternative.
Session: Podium Presentation
Program Number: S072