Prof. Dr. med. Michael Hirschmann is an internationally renowned specialist in knee surgery and knee replacement who practices at the Baselland Cantonal Hospital in Switzerland. His expertise in the field of the knee joint encompasses all aspects of knee surgery, including innovative procedures such as robot-assisted knee replacement. Since his appointment as head of the Knee Surgery and Sports Orthopedics team at the Baselland Cantonal Hospital in 2013, he has played a key role in helping the clinic gain international recognition and secure a firm place on the global map of orthopedics.
Prof. Dr. Hirschmann is known for his outstanding skills in endoprosthetics and in performing complex revision surgeries. His commitment to the advancement of knee surgery is reflected in numerous prizes and awards that recognize his innovative approaches and achievements. In addition to his clinical work, he is also active in the scientific community and leads a university research group at the University of Basel. His work and publications have had a significant influence on modern knee surgery.
In his role as Chief Physician and Director of the “Musculoskeletal Center” at the Baselland Cantonal Hospital, Prof. Dr. Hirschmann has restructured the Department of Orthopedics and Traumatology using an innovative “job-pairing” model to ensure comprehensive care for patients. His expertise ranges from conservative therapy to arthroscopic and open surgeries, as well as advanced methods in joint replacement and the treatment of cartilage damage. Of particular note is his work in treating patients with knee replacements, where he has developed and implemented innovative methods such as phenotype alignment and 3D-assisted prosthetic technology to achieve optimal results.
Prof. Dr. Hirschmann is also a sought-after expert for the diagnosis and treatment of pain following knee replacements and other postoperative complications. His many years of experience and his commitment to continuously improving treatment standards make Prof. Dr. Hirschmann an outstanding specialist whose expertise and empathy are valued both regionally and internationally.
Robot-assisted surgeries are becoming increasingly common and enable even more precise surgical procedures. The editorial team at Leading Medicine Guide spoke with Prof. Dr. Hirschmann about this topic.
Robot-assisted surgery represents a significant advance in medical technology and is increasingly revolutionizing the way surgeries are performed. This innovative approach utilizes highly sophisticated robotic systems to assist surgeons in performing precise and complex procedures. The robots offer unparalleled precision, stability, and control that far exceed the capabilities of conventional surgical techniques. Through the use of advanced imaging and real-time data processing, these systems enable improved visualization of the surgical site while minimizing the burden on the patient. The use of robot-assisted techniques has proven particularly effective in minimally invasive surgery, as they often result in faster recovery times, reduced postoperative pain, and shorter hospital stays. These technologies represent a significant step toward more precise and gentler patient care.
To successfully perform robot-assisted knee surgery, several criteria must be taken into account.
First, there must be a valid indication for performing knee replacement surgery. This requires a thorough assessment of the patient’s symptoms, previous treatments, a detailed examination of the knee joint, and a standardized X-ray examination. It is crucial to discuss the indication for surgery, as well as the potential risks and benefits of the procedure, in detail with the patient. This also includes assessing the knee joint condition to determine whether a partial or total knee replacement is necessary and whether the patient is medically fit to undergo such a procedure. Surgeons should be specifically trained in the use of the robot to effectively utilize the technology. Likewise, the surgical team must ensure that the operating environment is properly prepared, including the necessary instruments and surgical planning.
“In principle, only patients who have clear symptoms, a consistent clinical and radiological picture, and who have exhausted all conservative treatments are candidates for a knee replacement. Currently, robot-assisted knee surgery offers the option of implanting a total or partial knee replacement. Revision surgeries, however, are not yet possible with robotic assistance. The problem with revision surgery is that one never knows exactly how much bone remains after the initial prosthesis has been removed, which is essential for planning. In general, one must consider whether robot-assisted surgery makes sense or whether conventional surgery is sufficient. For one thing, the systems are not widely available enough to allow every patient to undergo robot-assisted surgery, since a robot must also be prepared for the procedure. For example, performing 5–6 surgeries a day would create time constraints in this regard. In principle, however, robotic surgery is accessible to all patients. The idea behind the robot is to provide better orientation within the patient’s knee joint during surgery. Patients with pronounced deformities, such as bowlegs or knock-knees, benefit the most. With the help of a robot, it’s possible to achieve a more optimal balance in these cases, since the respective ligaments can be better accounted for. In cases of severe deformities, it’s also important to be able to simulate the incisions beforehand, which is precisely what a robot makes possible,” said Prof. Dr. Hirschmann regarding the pros and cons of robotic surgery.
“The robotic arm, which is equipped with precise surgical instruments, is controlled by an experienced surgeon. It is a ‘Navigation System Plus’—the ‘plus’ refers not only to the navigation but also to the guided saw, which is guided within the plane specified by the surgeon and does not deviate from it. This makes the implementation of the surgical plan, as well as the extremely precise placement and alignment of the knee prosthesis, significantly more accurate through the integration of preoperative imaging data and real-time monitoring. To illustrate: In conventional prosthetics, there are so-called cutting blocks, and within this cutting block, the saw can still tilt by 2–3 mm, and the saw can also slip, resulting in a cut surface that isn’t quite as clean. “In robotic surgery, there are no cutting blocks at all; the saw is thicker, making it less flexible, and the guidance accuracy is within 1/4 mm,” explains Prof. Dr. Hirschmann.
Imaging and data analysis in robot-assisted knee surgery play a central role in optimizing the placement and alignment of the knee prosthesis.
“First, one must distinguish between the two different systems: image-guided and image-free robotics. With image-guided robotics, a computed tomography (CT) scan is performed before the operation to map the anatomy of the knee joint. During the operation, points are then captured to align the CT image with the robot’s navigation system, providing 3D information in real time. Image-free robots use a pointer to capture points on the knee joint (relevant landmarks), and a virtual knee model is created. The overarching goal of robotics is personalized knee replacement. In the past, every knee was treated the same way—everyone received the same implant. Yet each patient’s needs are highly individual. As a result, conventional procedures only achieve approximately 25% of the goals intended by the mechanically implanted prosthesis. This means that approximately 75% of patients are forced to accept a geometry they did not previously have, which may result in painful knee prostheses and force patients into an unnatural posture. “A personalized surgery is possible with the robot and an anatomically appropriate prosthesis,” explains Prof. Dr. Hirschmann, adding a comment on the important issue of ligament stability:
“The overall ligament stability—from extension to flexion—can be measured using the robot’s instruments. The surgeon receives precise information during the operation and can make adjustments intraoperatively. This is crucial—the knee must be stable across its entire range of motion and must not be asymmetrical. And that, ultimately, is the great advantage of robotic surgery.” The robot-assisted technique also enables a less invasive approach. Thanks to the precise control of the robotic arm, smaller incisions are required, leading to faster healing and reduced postoperative discomfort.
State-of-the-art technology at the Baselland Cantonal Hospital!
“Here at the Baselland Cantonal Hospital, we’ve been using robot-assisted surgery since October 2023. As far as the learning curve is concerned, it’s a quick process if you’ve used navigation systems before, since the robot is very similar to a navigation device. If you’re coming from a purely conventional surgical background, it does require some adjustment. The surgery itself takes about 15–20 minutes longer due to the time needed to set up the equipment. In addition to the fundamental advantage of having a robot at all, we’ve developed a so-called 3D phenotype concept to analyze each knee even more thoroughly and individually, so we can then treat it in the best possible way—whether conventionally or with the robot. Since October 2023, we have performed approximately 100 surgeries. As for patient feedback following robot-assisted surgeries, most report that they walk very confidently and feel good with their new prosthesis, which is certainly also due to the improved ligament guidance described earlier. However, using the robot alone isn’t enough—this is just the beginning of the journey. Perhaps in the future there will be even smaller tools that aren’t as costly. As a reference center for primary and revision joint replacement, our clinic is certainly a leader in Switzerland when it comes to robotic surgery, partly because we operate internationally. Many patients come to us from abroad because, as a larger center with university affiliations, we can also manage more complex cases, and I myself am a professor at the University of Basel with a research group focused on robotics and personalized prosthetics,” explains Prof. Dr. Hirschmann, offering one final piece of advice at the end of our conversation:
“The question ‘Why do I need a knee replacement?’ must be answered very clearly. The surgeon must be able to explain this. This is even more important in revision cases. Standardized diagnostics are necessary for this. If a patient is scheduled for an initial surgery, they should inquire about the surgeon’s case volume and certainly consider word-of-mouth recommendations to ensure they choose a provider who offers high-quality care. It’s not easy for patients to obtain reliable information in this area. Getting a second opinion can also be very important. And we mustn’t forget—the surgery is one thing, but follow-up care is another. Both have to be right. When it comes to revision surgery, you should be willing to travel a bit farther to ensure you really do receive the best possible treatment.”
Thank you very much, Professor Dr. Hirschmann, for this interesting insight into the world of robotic surgery!
