Laparoscopic instrument for holding, cutting and coagulation

Design and user research at the beginning

At the beginning of the project, we had to get to know laparoscopic operations and the challenges of the users. In a 2-day ergonomics workshop at the Tübingen Clinic, moderated by the Erbe in-house usability expert, we were able to try out the use of the instruments in a simulated manner and evaluate the different solutions using a wide range of different product samples available on the market. The comparative comfort tests with the users were particularly informative, because in practice the instruments are perceived and controlled almost exclusively with the sense of touch. Added to this is the sometimes unnatural hand and arm posture of the operator, sometimes over a long period of time. It therefore makes sense to design the handpiece in the direction of gripping comfort. Particularly memorable was the statement of a physician who described "the dignity of the instrument function". By this he meant that cutting into living human tissue should be associated with appropriate feedback in the surgeon's hand. A plastic housing that warps and may make crunching noises when squeezed would be a "no-go" in this respect.

Procedure

Thus inspired and sensitized, the design team set about finding the shape, creating various alternative design concepts and dozens of iterative optimizations. As a multifunctional instrument, the case must pack many functions into a very small space. The installation space for the mechanical components was one challenge, the optimal fit to the hand another. At the same time, the handle had to be comfortable to use even for small hands, and all the release functions had to be easily accessible. For large hands, however, accessibility is less of a problem than possibly closed or constricted grip areas. An ergonomic shape was therefore the essence for the success of the project.

Over the course of the design process, which lasted several months, we repeatedly produced comparable samples from our 3D CAD data and had them tested. There were weeks when our 3D printers didn't stop. During the course of the design development, we were able to deliver 3D prints in all quality levels up to the near-production functional prototype.