Since January 1, 2025, Professor Dr. med. Atesch Ateschrang has been Head Physician of the Department of Orthopedics and Traumatology at Kantonsspital Aarau (KSA) – the largest center for medical care in the Canton of Aargau. With his extensive clinical experience and evidence-based expertise, he is regarded as one of the leading orthopedic surgeons and trauma specialists in the German-speaking world. As a board-certified specialist in orthopedics, trauma surgery, and advanced trauma surgery, he offers a broad spectrum of treatments – ranging from acute injuries and fractures to complex joint operations and the care of severely injured patients (polytrauma).
His particular expertise lies in knee, hip, shoulder, and elbow surgery, complemented by many years of specialization in sports traumatology and reconstructive joint surgery. Since 2011, he has also been a certified foot and ankle surgeon. Before moving to Aarau, Prof. Ateschrang worked as Senior Consultant at the University Hospital Tübingen and as Head of the Trauma Center at the Evangelisches Stift Koblenz. There, he significantly shaped the management of complex injuries and received multiple awards for his surgical excellence – including from FOCUS and Stern.
At KSA, he pursues a modern, interdisciplinary treatment approach: patients benefit from highly specialized medicine, minimally invasive techniques, and close collaboration with partner centers such as the Center for Sports Medicine and the Center for Musculoskeletal Infections. In addition to his clinical work, Prof. Dr. Ateschrang is deeply committed to medical education and training, actively supporting the development of the next generation of surgeons. Through his dedication, he plays a key role in ensuring the highest quality of orthopedic and trauma care in the Canton of Aargau – evidence-based, patient-centered, and future-oriented.
In an interview with the editorial team of Leading Medicine Guide, Prof. Dr. Ateschrang explained which measures can preserve joints and what options exist for joint replacement.
The knee joint is one of the most heavily stressed joints in the human body – it not only carries body weight but also enables essential movements such as walking, climbing stairs, and sports activities. Pain, instability, or wear due to osteoarthritis, injuries, or misalignments can significantly impair quality of life. The goal of modern knee surgery is therefore to preserve as much natural function as possible. Whenever feasible, joint-preserving procedures are prioritized – for example, through axis corrections or cartilage reconstruction. If joint wear is already too advanced, partial or total joint replacement (endoprosthesis) can sustainably restore pain relief and mobility. Innovative surgical techniques, customized implant solutions, and close interdisciplinary follow-up care contribute to achieving the best possible outcomes – for improved quality of life and mobility in everyday activities.
A joint-preserving procedure on the knee joint is particularly preferable to an endoprosthesis when arthritic changes are not yet too advanced or affect only partial areas of the knee joint. Joint preservation is especially favored in highly active or professionally exposed patients.
“The topic of joint preservation and replacement in the knee always begins with the question of what exactly is wrong in the joint. Before considering therapy or even joint replacement, one must understand which structures are affected and why. At the KSA Center for Orthopedics and Traumatology, we examine this very thoroughly – all in one place. This means we take into account each patient’s individual anatomy: the leg axis, i.e., whether the leg is straight or shows a malalignment such as bowlegs or knock-knees, as well as the so-called ligamentous situation – in other words, whether the ligaments stabilize the knee sufficiently. From this constellation, stress often arises for the meniscus or cartilage. From experience, we know that many patients, for example, come to us with a meniscus injury. In such cases, we always ask: Is this really just an isolated injury, or is there an underlying cause – such as a malalignment or subtle instability that may not be obvious at first? The meniscus can compensate for such stress for years or even decades. But at some point, it fails – leading to a tear or wear, such as root insufficiency. And that often marks the beginning of the next cascade: cartilage damage occurs, the joint changes structurally, and then we are faced with the challenge – even in relatively young patients – of how to preserve the joint for as long as possible. Especially in younger patients, joint replacement should be delayed as far into the future as possible. This often raises the question: Is surgery necessary at all, or is conservative treatment sufficient at first? This cannot be answered in general terms, as it depends very much on the cause. If, for example, someone has a crooked leg – a significant axis deviation – purely conservative treatment, such as injections, physiotherapy, or pain medication, is often not only insufficient but may even be harmful. Because during the time one tries to alleviate symptoms, joint damage may progress further. And if surgery is decided on later, the joint may already be so damaged that the chances for successful joint-preserving measures are reduced”, explains Prof. Dr. Ateschrang at the beginning of our conversation, continuing:
“It is completely different if the axis is correct and the ligaments are stable. Then, in the case of a meniscus injury, one can certainly proceed conservatively. This may include injecting hyaluronic acid into the joint, possibly combined with cortisone, or working with ACP – that is, processed autologous blood re-injected into the joint. If there is also a slight axis deviation, an orthosis can be used – a so-called unloader brace, which relieves the joint. Its effectiveness is well documented scientifically. Of course, it cannot replace a bony correction, but it can help relieve pain and slow progression of the damage. Surgical axis correction – a so-called corrective osteotomy – is the treatment of choice when the joint is biomechanically permanently overloaded. Here, the bone is cut and stabilized in a new position so that the leg axis is corrected. This sounds drastic at first, and many patients are hesitant. In such cases, we often suggest a so-called brace test. The patient wears an orthosis that simulates the corrected leg axis. And what we repeatedly observe: patients notice that they feel significantly better. This is often the decisive step – because suddenly, the conviction arises that surgery makes sense and is purposeful. The test is therefore therapeutic, diagnostic, and also psychological. Ultimately, it is always about finding the best solution for each individual patient. We carefully assess what is happening in the joint and then decide together whether conservative treatment is sufficient or whether surgery is advisable. The focus remains on preserving the joint for as long as possible – with the goal of maintaining quality of life and preserving the knee’s natural function”.
Imaging procedures such as conventional X-rays in multiple planes, full-leg standing radiographs to assess leg alignment, magnetic resonance imaging (MRI) to visualize cartilage, meniscus, and ligaments, and in some cases diagnostic arthroscopy provide detailed information about the joint situation. Last but not least, patient expectations play a central role: those who want to remain active and preserve their own joint for as long as possible benefit from early joint-preserving therapy – provided anatomical and functional prerequisites allow. On the other hand, if several joint compartments are already severely damaged, the cartilage is extensively degraded, and pain is constant regardless of load, artificial joint replacement is often the more reasonable option.
Knee replacement today can be tailored much more individually – far more than just a few years ago. In the past, prosthetic solutions were often standardized, essentially “off the shelf,” with little regard for the patient’s specific anatomy. Fortunately, that has changed.
“The knowledge and technical possibilities have advanced to the point that, for example, in the case of so-called medial osteoarthritis – wear on the inner side of the knee, which is the most common – a very targeted partial knee replacement can be implanted, such as a so-called medial unicompartmental prosthesis. However, certain static conditions must be met, such as the leg axis being within an acceptable range. In the case of a pronounced bowleg, for example, it must be considered during planning that this axis deviation does not remain too severe, as otherwise the new partial replacement would be excessively stressed. This is exactly where digital, computer-assisted surgical planning comes into play. To prepare for such procedures, we always perform so-called full-leg standing radiographs – meaning an X-ray from the hip joint to the ankle that shows the entire bony situation. This allows us to assess pelvic alignment, the anatomy of the knee joint, and precisely evaluate the adjacent bone segments above and below. Using this imaging data, the individual situation can be precisely analyzed, and the exact positioning and size of the prosthetic components can be digitally planned. This planning is accurate to the millimeter and also includes the necessary axis correction. In principle, the surgery already takes place virtually before the actual procedure – with the goal of replicating the planned result as precisely as possible in the OR”, explains Prof. Dr. Ateschrang, adding a comment on robotic assistance:
“Robot-assisted procedures are currently under discussion and subject to intensive evaluation. So far, we have not used them, primarily because the proven benefits in experienced hands are not significantly better than with classic manual surgery. According to studies, after three to six months, there are no relevant differences in outcomes with an experienced surgeon. Costs must also be taken into account. What is decisive in both cases is precise digital preparation. If this is done carefully and consistently implemented in the OR, excellent results can also be achieved without robotic assistance. Nevertheless, there are various robot-assisted systems, such as CT-based methods that allow particularly accurate implantation. But here, too, one must note that these technologies have not yet become widely established – it is estimated that only about ten percent of clinics in Europe use these systems regularly. If the results were truly measurably better, the technology would certainly have spread more quickly and broadly. For us, the conclusion is clear: as long as manual implantation combined with modern digital planning in experienced hands leads to equally good results, we rely on what provides the greatest benefit to our patients – individualized, precise, and sustainable”.
For larger or more complex cartilage defects, modern procedures such as autologous chondrocyte transplantation (ACT) are now used, in which the patient’s own cartilage cells are harvested, multiplied in the lab, and later implanted into the defect. Alternatively, cartilage-bone transplants can be performed – either with the patient’s own tissue or with donor grafts, especially in deep defects. Matrix-associated methods such as MACI, where cells are seeded onto biological scaffolds, allow uniform defect filling and better integration. In cases of malalignment such as bowlegs or knock-knees, an accompanying corrective osteotomy may be necessary to support healing. In addition, biological therapies such as PRP, growth factors, or stem cells are being explored to promote regeneration. All these approaches aim to preserve joint function, relieve pain, and delay prosthetic replacement for as long as possible – provided diagnostics and therapy are precisely aligned.
Minimally invasive knee surgery has made significant progress over the past decade – both in surgical techniques and in the use of modern instruments and technologies. For patients, these advances usually mean a much faster recovery: less pain, reduced need for medication, shorter hospital stays, and earlier mobilization.
Prof. Dr. Ateschrang explains: “After a partial or total knee replacement, patients usually stay in the clinic for three to five days – depending on the joint’s individual response to the procedure. Some people tend to experience more swelling or pain, while others recover more quickly. These differences are, of course, taken into account when planning discharge. Depending on their condition, patients either go directly home with outpatient physiotherapy or to an inpatient rehabilitation facility immediately after their hospital stay to support further recovery. The return to everyday life also depends on the type of procedure and individual circumstances. After bony procedures, such as an axis correction, healing is usually faster than after soft tissue reconstructions, such as an ACL reconstruction. The reason is that a graft made of soft tissue takes much longer for biological integration – this so-called remodeling process can take six to twelve months. However, this does not mean that sports activities must be avoided entirely for that long. Usually, initial sports activity is possible after two to three months, which can then be gradually increased step by step”.
Especially in athletically active or performance-oriented individuals, movement coordination, muscle strength, and dynamic load-bearing capacity – for example through jumping ability – are compared side by side.
“In some cases, this is done using modern technologies such as high-resolution cameras or computer-assisted evaluations. In collaboration with experienced physiotherapists on-site, such test procedures can also be carried out directly at the KSA center. And even after surgery, care does not end with discharge. All patients continue to be monitored through follow-up appointments. These are tailored individually – sometimes at longer intervals, sometimes more closely spaced, depending on progress and personal needs. Some patients want more feedback and guidance, while others do well with fewer contacts. In any case, a suitable approach is found to ensure a safe return to everyday life, work, and sports”, emphasizes Prof. Dr. Ateschrang.
It usually takes about six to twelve weeks before patients can move safely in everyday life again. Light physical activities such as cycling or jogging are often possible after three to four months, while contact sports should be avoided for longer.
Interdisciplinary collaboration plays a central role in the long-term success of treating knee problems. Knee disorders and injuries are complex and affect not only the joint itself but also surrounding muscles, ligaments, the nervous system, and often the entire musculoskeletal system. Therefore, comprehensive care is essential to achieve optimal results.
“Our hospital is at the cutting edge – with state-of-the-art methods such as 3D analyses, digital surgical planning, and excellent equipment both in the operating room and across diagnostics and therapy. We offer medicine at the highest level – not only surgically but also deliberately non-surgically. Our principle is: surgery is performed only when it is truly necessary and beneficial. That is why we always place individual assessment at the forefront. Each patient is analyzed individually – with regard to current symptoms as well as long-term prognosis. Especially in more complex cases, such as patellofemoral instability, careful three-dimensional diagnostics are essential. Only in this way can we determine where the actual problem lies, how it might develop if untreated, and whether surgery offers long-term advantages – or whether conservative measures are the better choice. We see our task as providing well-founded medical guidance, explaining all options clearly, and transparently outlining both opportunities and risks. In the end, of course, it is the patient who makes the decision. We show what we call the ‘golden path’ – the medically optimal solution – always supplemented with realistic alternatives. Our goal is to advise each person individually, with a holistic view of what is medically feasible but also truly suitable for their life”, stresses Prof. Dr. Ateschrang, and with that we conclude our conversation.
Thank you very much, Professor Dr. Ateschrang, for this informative discussion!
