Jennifer Rosen, MD, Aaron Size, Yuzhang Yang, Andre Sharon, PhD, Alexis F Sauer-Budge, PhD. Boston University School of Medicine, Fraunhofer USA – CMI.
INTRODUCTION: Compared with traditional open surgery, minimally invasive surgery may improve recovery and patient satisfaction while maintaining surgical principles. Laparoscopic, single incision, natural orifice and robotic approaches each hold their own appeal. However, they lack the ability to manipulate organs as easily as the human hand. The downside of adding hand-assistance is that it requires an additional larger incision. Robotic surgical systems are expensive, require a great deal of training, and thus their use is limited. Advances in minimally invasive surgical techniques will require new types of surgical tools with increased functionality of the end effectors. Multifunctional tools that also improve its dexterity with respect to those currently available are highly desired.
DESCRIPTION OF METHODS: To address this challenge, we designed, built and tested the first prototype of a laparoscopic tool that provides the dexterity of a hand. The “hand” has two jointed fingers and a jointed thumb attached to a laparoscopic sheath that can be collapsed into a small space to fit through a 12 mm trocar or other small orifice. The handle provides control for 3 independent degrees of freedom: 1) finger motion (bending/spreading), 2) finger tip bending, and 3) thumb bending. The tool can be used for pinching, grasping, and spreading motions. Furthermore, the thumb is “double jointed” so that the tool can be converted to a rake configuration (similar to a hand’s three middle fingers) to allow lifting motions. The initial prototype has been tested in a cadaver lab to demonstrate its utility.
PRELIMINARY RESULTS: Our “lap-hand” was able to complete standard surgical tasks in a simulation device in a time comparable to open and laparoscopic approaches, including bowel manipulation and peg movement. Cadaver testing revealed the ability to grasp, elevate and move liver, stomach, colon and small bowel in a fashion expected by the hand. No adverse events were noted and no bowel injury or perforation resulted as one might expect from over-grasping.
CONCLUSIONS: We have designed, built, and tested a first prototype of an artificial hand for minimally invasive surgery. Use of such tools could both reduce the number of hand-incisions required and potentially transition more patients to undergo their abdominal procedures laparoscopically.