Training surgery with the DynamicHIPS system

When surgically inserting an artificial hip, the preparation of medical staff jumps from theory to practice directly on the patient. The training system OrthoMiniGames now offers a simulation as an intermediate step. The use of virtual reality optics combined with tactile devices provides medical professionals the opportunity to conduct the procedure within a haptic experience before approaching the patient.

Two years ago, at MEDICA-tradefair.com we talked to Dr. Mario Lorenz about the project while it was still in development. Now that it has been successfully launched this year, he explains what distinguishes the training system from other virtual training systems and what its technology is all about.

Dr. Lorenz, how does the surgical training simulation work and what is the technology behind it?

Dr. Mario Lorenz: The training simulation uses virtual reality (VR) glasses that allow users to practice the procedure immersively in a virtual operating room. This includes a refined training system with multi-user functionalities. Within the simulation, the implantation of an artificial hip can be practiced with all its steps. The special feature here is that we are the only ones in the world so far to offer all the steps in a realistic haptic simulation.

We use the Virtuose haptic device from Haption SA for this purpose. This company will also be showing the surgical training simulation at MEDICA 2023. At the trade show, it can be used to test the first two steps to insert an artificial hip.

For the remaining steps, we use a hammering device specially developed at the Chemnitz University of Technology, for which a patent application has been filed. This can be used to realistically simulate the hammering in of the implants. We have already tested this with our partners at Leipzig University Hospital and the Medical University of Graz within biomechanical experiments. In this way, the individual steps and the forces and torques that occur could be precisely measured and mapped with the help of donated samples.

Why is the training system particularly helpful for orthopedic trauma surgery?

Lorenz: In Germany alone, we insert about 200,000 artificial hips every year, both primary and revisionary. That makes it an extremely common operation. On top of that, the training of medical professionals in this area currently takes place on the affected person under supervision. This is in need of improvement, as it means that the operation cannot be practiced completely without danger. The sensorimotor skills needed for the operation must first be learned. Realistic haptic simulation is crucial for this.

To what extent could findings from the previous project and the simulators developed for it help with the new training system?

Lorenz: With the previous project, we started more or less from scratch in 2016. At that time, the goal was to bring the various modules together in such a way that we had a realistic virtual patient anatomy and could implement a training system in VR. In doing so, we focused on a single surgical step. The knowledge we gained about haptic input devices showed us that the existing technology was not haptic-transparent enough. The weight of the robot was noticeable and thus distorted the haptic sensation in the simulation.

For the new training system, we tried to solve this problem in two ways. On the one hand, with the Virtuose haptic device and, on the other hand, by trying to adapt the control technology so that it becomes more haptically transparent.

The training system that has now been implemented also recognizes errors and displays them. It can now be trained modularly in three different difficulty levels. With the multi-user system, virtual instruction can be given to any number of spectators. Recordings for training purposes are also possible. In principle, we have taken the experience and knowledge gained from the first project, and based on this, we have once again developed a completely new training system.

Is the training system already being used in clinics?

Lorenz: The research project was officially completed in April. Toward the end, we evaluated the training system in Chemnitz at the Zeisigwaldkliniken Bethanien. This was done together with the entire orthopedic trauma surgery staff, consisting of 17 test subjects ranging from medical students to the head physician. The feedback was positive, and the simulated training made the test subjects feel more confident when approaching the first real patient.

The next step is to integrate the training simulation into the actual patient training situations. However, since the research project is finished, we first have to look for further funding in order to really bring it to the clinics.

How do you see developments in VR for surgical training? What has happened in recent years and where is further potential for development?

Lorenz: There has been an incredible amount of development with both VR and augmented reality. However, it strongly depends on the individual disciplines. For training in the context of education, there are already good training simulators with realistic feedback in the area of operations with low forces - such as laparoscopic procedures.

Many companies have also developed solutions in the last five to ten years for areas where greater forces are at work. However, these are limited to purely visual training systems. In this case, you learn the steps one after the other, but there is no opportunity to train the manual skills. This is a big issue for the surgical field. We need training with realistic haptics in simulation. And I think there is still a lot of potential for development and advancement there.