Floating docking technique: a simple modification to improve the working space of the instruments during single-port robotic surgery.

ABSTRACT

OBJECTIVE: To compare the range of motion and ergonomic characteristics of single-port robotic instruments in the setting of the "floating" versus "flat" docking technique using the GelPOINT® system. MATERIAL AND METHODS: The basic principle of the floating docking technique resides in the GelSeal cap and trocar (s) being 8 cm off the skin level with the Alexis® acting as a conduit between the trocar (s) and the body while preserving insufflation. In the setting of a dry lab study, we measured the range of motion of one robotic instrument with the "floating" and the "flat" docking technique in two different situations depending on whether the distance between the incision and the target was more or less than 10 cm. RESULTS: The minimum required distances between the target and the tip of the cannula for activation of the wrist and elbow were 5 and 10 cm, respectively. When the target was near to the cannula (i.e., less than 10 cm), the floating technique was associated with a significant increase in the range of motion of the instrument in all directions. The working space volume of the instrument was increased by more than 390% (from 101 to 497 cm3) when the surgeon switched from flat (standard) to the floating technique in the setting of a target close (i.e., less than 10 cm) to the cannula CONCLUSION: The floating docking technique is a simple and effective way to increase the working surgical space, especially in confined and narrow surgical fields with a target closer than 10 cm from the skin.