Fully automated robots for the planning and implantation of total hip arthroplasty have completely withdrawn from the market. Reasons were technical problems during the reaming process that lead to postoperative neurological problems. This lead, especially in Germany, to numerous court cases and created a hostile environment regarding robotic orthopaedic surgery.

The first steps in the development of a robotic assisted system for total hip arthroplasty are presented. This system will be able to plan and mill both femoral and acetabular implant seat. This project aims to combine the advantages of minimally invasive techniques and navigational systems with the accuracy that robotic assisted bone milling can provide. One of the main goals is the study of the technical problems of previous systems and to develop methods to prevent those.

The project-name is RomEo (Robotic minimally invasive Endoprosthetics), the main project partners are the Helmut-Schmidt University/Hamburg and the Department of Trauma and Orthopaedics of the BG Trauma Hospital Hamburg. The paper focuses on:

The determination of forces acting on the femur during milling: The determination of the ideal minimally invasive access route in cadaver operations

The “workspace” created in minimally invasive hip surgery as determined in cadaver operations, including a 3D reconstruction

Possible solutions of the problems of non-invasive patient fixation as determined in cadaver testing with different fixation methods

Feasibility of 3D operation simulation using Voxelman data, access route data and implant CAD data