Prof. Dr. med. Nicolai El Hindy is the Chief Physician of the Department of Neurosurgery and Spine Surgery at the St. Marien Hospital Lünen and is considered one of Germany’s leading specialists in advanced, high-precision spine surgery. As a board-certified neurosurgeon with an additional specialization in Special Neurosurgical Intensive Care Medicine, he combines extensive scientific expertise with innovative technology and years of clinical experience. Prof. El Hindy places particular focus on robot-assisted, navigated spine surgery.
By utilizing the cutting-edge ExcelsiusGPS® system, he is among the pioneers of this minimally invasive technique in Germany. This allows surgeries to be performed with even greater precision, safety, and gentleness for the patient. In the field of disc prosthetics, which aims to preserve mobility and quality of life, Prof. Dr. El Hindy also sets modern standards. In addition to his specialization in spinal disorders, he treats complex brain pathologies such as tumors, vascular malformations, or spontaneous hemorrhages — always with a patient-centered, individually tailored approach.
His dedication extends far beyond the operating room: Prof. Dr. El Hindy is an internationally sought-after speaker, trains colleagues worldwide in robot-assisted surgery, and actively supports young medical professionals through research projects and fellowships. He is a member of prestigious professional societies such as the German Society of Neurosurgery and the German Spine Society, contributing his expertise to international networks. At St. Marien Hospital Lünen, a facility grounded in Christian values, Prof. Dr. El Hindy shapes the department by combining top-tier medicine with social responsibility and human connection.
Here, patients benefit from interdisciplinary, high-quality care and the innovative strength of a physician who consistently merges medical excellence with personal attention.
To preserve the natural mobility of the spine despite disc degeneration, disc prosthetics can be used — the editorial team at Leading Medicine Guide spoke with Prof. Dr. El Hindy about this topic.
Disc prosthetics is a modern procedure in spine surgery that offers patients with severe disc damage an important alternative to traditional fusion surgery. The goal of this innovative technique is to preserve the spine’s natural mobility, alleviate pain, and sustainably improve quality of life. By using an artificial disc, the function of the degenerated or damaged disc is replaced, often allowing patients to regain mobility more quickly and reducing the long-term risk of damage to adjacent spinal segments. Especially in well-selected patients, disc prosthetics offers an effective option for restoring the spine both functionally and anatomically.
Typical indications include chronic back pain due to isolated disc damage — either in the lumbar or cervical spine — with maintained stability of the surrounding spinal structures.
“Disc prostheses can essentially be divided into two areas: cervical spine prosthetics and lumbar spine prosthetics. This distinction is important because both regions place different demands on mobility — especially in the cervical area, where natural mobility is quite high. Such a prosthesis is more suitable for patients whose degeneration has not progressed too far, as degeneration always comes with a reduction in mobility. The body often begins to stiffen on its own, for example, by depositing bone. If this has advanced too far, it becomes difficult or even impossible to restore mobility with a prosthesis. In general, prosthetics are more suitable for patients who are still flexible and active. These are often athletic individuals or those with a very active lifestyle — whether professionally or privately. It’s not just about the disc itself, but also the muscles, ligaments, the entire system. And that’s exactly what often works particularly well in these patients,” explains Prof. Dr. El Hindy at the beginning of our conversation and adds regarding diagnostics:
“Imaging for patients with degenerative changes generally follows a standardized protocol. Usually, an MRI is performed first — it’s the most important method for assessing the underlying pathology of the symptoms. Functional imaging is also commonly used in cases of degenerative disease. Here, the patient performs specific movements, such as forward and backward tilting of the head in the cervical spine or bending and stretching in the lumbar spine. These movements are recorded on lateral X-rays to determine whether there is still relevant mobility in the area that might be operated on. These images also provide clues as to whether a disc prosthesis is an option — or not. An exclusion criterion, for example, is spinal instability. This can be seen in functional imaging. If the vertebral bodies move during bending and stretching but remain stably aligned, that’s generally a good sign. However, if one vertebra slips over the other — for instance, if the third lumbar vertebra significantly slides over the fourth when bending forward — it indicates instability. In such a case, a prosthesis would not be suitable.”
The long-term prognosis after disc prosthetics differs in several key ways from traditional fusion surgery (spondylodesis). The fundamental goal of disc prosthetics is to maintain the mobility of the affected spinal segment, whereas spondylodesis aims for complete fusion of the segment.
“The central idea behind using a disc prosthesis is preserving mobility. That’s exactly what sets it apart from fusion surgery: the affected segment remains mobile. Studies and clinical experience show that preserving this movement leads to fewer problems in adjacent spinal segments over the long term — so-called adjacent segment disease occurs less frequently. This means that not only does the diseased segment retain its mobility, but the neighboring areas are also protected, as they don’t have to take on as much compensatory load. Of course, natural wear and tear continues over a lifetime — it cannot be completely stopped. However, a prosthesis interferes less with the biomechanical system of the spine than a fusion. That said, fusion surgeries are still sometimes unavoidable. They often have a negative image, but many patients, for example after a single fusion, notice no significant difference in everyday life. It usually becomes critical only with very large fusions extending from the thoracic spine to the pelvis, though these are rather exceptional cases. In many cases, prostheses achieve excellent long-term results — while maintaining a natural sense of movement,” emphasizes Prof. Dr. El Hindy.
Modern disc prostheses are highly advanced implants specifically designed to best replicate the natural function and mobility of the human intervertebral disc. Both the choice of materials and the technical design play a crucial role in durability, biocompatibility, and mobility.
Prof. Dr. El Hindy comments: “Disc prostheses are made from materials that have been proven for decades in joint replacement — such as in knee or hip prostheses. Typically, the prosthesis consists of two titanium plates anchored into the vertebral bodies above and below. Titanium is particularly well-suited because it integrates well with bone and provides stable fixation. Between the titanium plates is a movable polyethylene core, which functions like a ball joint and allows for natural segmental mobility. The technology is well-established: the current prosthesis models have been in use for around 30 years. Over this time, extensive long-term studies have shown good outcomes. Durability tests simulate several decades of use — typically, the implants are designed to last at least 40 years. In practice, this durability is not just theoretical. There are patients who have been living with such a prosthesis for 30 years — with consistently good function and preserved mobility in the affected segment. Disc prosthetics is thus not only a modern but also a proven implant.”
Technically, disc prostheses are designed to allow multiple directions of movement: flexion and extension, lateral bending, and rotation. This multidirectional mobility is crucial for maintaining the natural dynamics of the spine and avoiding overloading adjacent segments. Some prosthesis models are additionally designed with shock-absorbing features to better mimic the natural distribution of forces on the spine.
Although disc prosthetics offers a promising alternative to traditional fusion surgery (spondylodesis), like any spinal surgery, it comes with certain risks and potential complications.
General risks of disc prosthetics include surgical site infections, bleeding, wound healing disorders, and injury to adjacent structures such as nerve roots, blood vessels, or the spinal membranes. Thrombosis or embolism are also among the general perioperative risks. Specific complications related to the prosthesis itself primarily concern the positioning and function of the implant. If the prosthesis is not placed exactly, it can lead to spinal misalignments, improper loading, or unnatural movement patterns. As a result, pain may persist or even worsen. However, many of these risks can be significantly reduced through modern techniques, including minimally invasive surgical procedures that preserve surrounding tissue as much as possible and enable faster recovery. The expertise of the treating physician is extremely important in this regard.
“When performing a disc prosthesis surgery — especially in the cervical spine — the surgical approach is essentially the same as that used in traditional fusion surgery, which remains the gold standard in Germany. Nevertheless, prosthesis implantation differs significantly in its technical execution: it requires more experience and precision, as it’s not only about removing the pain-causing herniated disc but also about preserving segmental mobility. With prostheses, implant size and positioning must be exact. For example, using an implant that is too tall can cause hyperextension of the posterior facet joints, leading to new issues such as neck pain. Such problems occur less frequently in fusion surgeries because the mobility is eliminated anyway. The choice of the right implant is also crucial. There are many different models on the market, differing in height, width, mechanics, and materials — some contain nickel, which can be problematic in cases of allergy. For women, implants with a minimum height of 6 mm are often too tall. Stability also plays a role: some prostheses require special anchoring techniques, such as keels that are driven into the bone, providing good primary stability from the outset. Prostheses must therefore be carefully matched to the patient’s anatomy and needs. This requires a broad selection of implants and considerable surgical experience. A prosthesis is not ‘off the shelf’ but is carefully planned and selected. The actual surgery — for example, a cervical spine prosthesis at one level — typically takes about an hour. However, success depends not only on the duration but on the precise preparation and execution in detail,” emphasizes Prof. Dr. El Hindy, adding:
“Patients receiving a disc prosthesis can generally return home relatively quickly. After a cervical spine procedure, the main risk is postoperative bleeding, which could potentially compress the trachea. Therefore, patients stay at least one night in the hospital for observation. After this period, the risk of such complications drops significantly. Medically, most could be discharged the next day — as is common practice in some other countries. In Germany, however, economic factors mean that patients usually stay three nights, as shorter stays would result in financial losses for the hospital. This policy has not yet been changed as part of hospital reform — which focuses more on which clinics are allowed to perform certain procedures, rather than on the billing for length of stay.”
Surgery on the lumbar spine is somewhat more involved. It usually takes about two hours and is performed through an abdominal approach. Accordingly, the average hospital stay is four to five days.
“Even though the incisions are small — about two centimeters in the cervical area, five centimeters for one lumbar level, seven to eight centimeters for two levels — ‘minimally invasive’ here mainly refers to the gentle access: unlike posterior approaches, where the muscle must be detached from the bone, the anterior approach uses natural tissue planes. The tissues are simply pushed aside. This spares the musculature and makes the procedure much more comfortable for the patient overall — especially with regard to postoperative mobility, where functioning muscles are crucial. This anterior approach is by no means new, but it is increasingly rarely mastered. Particularly for lumbar spine surgeries, the approach is technically demanding, which is why vascular surgeons are often involved in other countries. In Germany, the spine team usually performs the approach themselves. Of course, every patient is thoroughly informed in advance about the procedure — including potential risks, such as injury to the trachea, esophagus, or recurrent laryngeal nerve in the cervical area. For abdominal approaches, the ureters, bladder, and other organs are nearby. Such risks are extremely rare but are always discussed. Long-term studies show that these approaches are generally very safe,” explains Prof. Dr. El Hindy.
After disc prosthesis surgery, patience is initially required — even if patients usually feel relatively good again in everyday life quite quickly. The crucial factor is that the prosthesis first integrates firmly into the bone. This process takes about three months. During this time, the spine must be protected to allow for a stable connection between bone and implant.
Prof. Dr. El Hindy recommends: “In the first four to six weeks after surgery, patients should largely avoid physical strain. Light walks, changing positions (sitting, lying, standing), and basic isometric exercises (i.e., holding exercises without large movements) are allowed — and are also offered as part of supervised physiotherapy. Load-bearing on equipment or intensive training, however, is taboo during this phase. Rehabilitation measures usually do not take place immediately after the operation but only three months later — when the prosthesis has stabilized. Then targeted strengthening and movement training can begin to regain full functionality. About three months after surgery, a follow-up examination is also conducted to check whether the prosthesis is correctly positioned, well integrated, and has not shifted. Only when this check is unremarkable are patients considered ‘cleared’ for all activities. For physically active people: depending on the sport, different rest periods are necessary. For sports involving sudden changes of movement or high loads — such as tennis, soccer, golf, or weightlifting — it’s best to wait three to six months before resuming. After that, a return to previous activity levels is usually possible without problems — many former patients fully participate in their sports again.”
Unlike a fusion surgery (spondylodesis), where two vertebral bodies are permanently connected and lose their mobility, the implantation of a disc prosthesis largely preserves the dynamic function of the segment. This mobility has a crucial impact on the distribution of loads throughout the spine.
The health of the intervertebral discs depends on various factors, with genetic predisposition playing a particularly large role, especially in the lumbar spine. Particularly in younger patients with lower back issues, no clear trigger can often be identified, suggesting that genetics are a key cause.
“In the cervical spine, on the other hand, signs of wear are more often related to occupational stress. People who frequently work overhead — such as painters, electricians, or automotive mechanics — are particularly prone to disc damage. Intensive competitive sports at a young age can also stress the lumbar discs. To protect the discs, it is important to move back-friendly in everyday life. For example, when lifting loads, always bend the knees and avoid twisting movements under load, as these are particularly harmful to the discs. It’s also important to strengthen the core muscles — the abdominal and back muscles — as stable musculature supports the spine and can prevent or delay complaints. Regular exercise and targeted training, such as back school or other strengthening exercises, are helpful. Additionally, one should avoid prolonged sitting, change positions frequently, and generally stay active rather than being overly cautious. However, for the cervical spine, muscle training helps only to a limited extent, as there is less supporting musculature. Therefore, it’s especially important to reduce overhead stress and ensure ergonomic working conditions. While not everything can be influenced, conscious movement, good posture, and targeted training can significantly reduce the load on the discs and thus minimize the likelihood of problems or surgeries,” advises the spine specialist.
At St. Marien Hospital in Lünen, approximately 100 cervical spine disc prostheses and about 50 lumbar spine disc prostheses are implanted each year. Recently, the number of surgeries has even increased, partly because the two locations in Lünen and Werne have been merged.
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Especially when implanting in the lumbar spine, it is crucial that the prosthesis is positioned very precisely in the center. Unlike a spinal fusion, where a small deviation of a few millimeters is not as critical, the prosthesis must be placed exactly to function optimally. To ensure this precise placement, St. Marien Hospital uses robotic navigation, which enables three-dimensional orientation and perfectly indicates the midline. This technology was introduced there about a year and a half ago and is a unique feature, as not many hospitals use robotics for this type of spinal surgery. Another advantage of robot-assisted navigation is the reduction of radiation exposure for both patients and the surgical team, as the procedure can be performed more accurately and with less radiation. In the future, artificial intelligence will likely play a key role in helping to better determine which patients are suited for which type of surgery—prosthesis or fusion. Factors such as smoking, osteoporosis, or the patient’s social situation come into play here. AI could thus assist in selecting the most appropriate treatment, while the technical execution of surgeries will increasingly be performed more precisely and efficiently by robots and navigated systems. Overall, the combination of robotics and AI holds great potential to improve care in spinal surgery, even though the direct technical use of AI in the operating room itself is still limited. The rapid development of robotics in hospitals is fascinating and demonstrates how modern technologies can be meaningfully applied across many medical specialties, even if the significance of robotics and AI varies depending on the medical field, concluded Prof. Dr. El Hindy at the end of our conversation.
Thank you very much, Prof. Dr. El Hindy, for this fascinating insight into the handling of disc prosthetics!
