The Minimally Invasive Manipulator: An ergonomic and economic non-robotic alternative for endoscopy?

Introduction: Since the da Vinci robotic system was introduced, it has been reported to have ergonomic advantages over conventional laparoscopy (COV). High investments associated with this system challenged us to design a more economical, mechanical alternative for improvement of laparoscopic ergonomics: the Minimally Invasive Manipulator (MIM). Material and methods: An earlier reported MIM prototype was investigated. Its shortcomings were input for the establishment of design criteria for a new prototype. Results: A new prototype was developed, aiming at improved intuitiveness and ergonomics. The handle and instrument tip were redesigned and the parallelogram mechanism was converted from linear moving parts to mainly rotating parts. Discussion: The new prototype was tested by a panel of experts and novices during an indicative ergonomic experiment. A major advantage of the MIM seems to be the possibility to perform laparoscopic surgery in a sitting position, in line with the working axis, instead of standing at the side of the patient. At an estimated cost level of 10% of the da Vinci system, the MIM can be an economical alternative for the enhancement of laparoscopy ergonomics. However, further development for clinical feasibility is necessary.