As Head of Spinal and Pelvic Surgery at the etzelclinic in Pfäffikon, Prof. Clément Werner, MD, began specializing some twenty years ago in a particular joint that can cause a great deal of pain, yet is rarely the focus of orthopedic attention: the sacroiliac joint. Through countless scientific publications, he has earned a first-class reputation in research and teaching in this field. Prof. Clément Werner developed his own implant to stabilize the sacroiliac joint. Researching, teaching and ensuring the well-being of his patients through the best possible treatment methods – this is what drives the renowned physician and experienced specialist. Leading Medicine Guide spoke to him about the sacroiliac joint and its arthropathy.
Leading Medicine Guide: Today we are talking about painful sacroiliac joints. You describe it as “an underdiagnosed problem”. In practical terms, this likely means that many people are walking around with this type of back pain and find it difficult to get help. Could you first explain to us what the sacroiliac joint is and where it is located?
Prof. Dr Clément Werner: The sacroiliac joint is also known as the sacroiliac joint, and the name gives a clue as to where it is located. Where the lumbar vertebrae merge into the coccygeal vertebrae, the sacroiliac joint connects the spine to the pelvic bones. It is not a joint like all our other body joints, because it has only minimal mobility. But it represents a complex and important connection point, because it stabilizes the entire back and thus our upright posture, while at the same time transferring force from the upper body to the legs. When walking, for example, the joint moves in very small movements; in fact, there are actually two joints, one on each side of the spine. The sacroiliac joint is held in place by large, strong ligaments and many small ones.
Leading Medicine Guide: When you describe it like that, one realizes how easily incorrect movements, minor anatomical imbalances, poor posture, uneven strain or poor sitting posture can become a problem here over time.
Prof. Dr Clément Werner: Exactly; the symptoms usually appear in later life, and those affected describe them as deep-seated back pain that occurs on one side or both sides and can radiate from the buttocks to the thigh or even down to the calf. With an incidence of 70 per cent, this deep lumbar back pain is a very common condition. In a third of cases, the cause lies in the sacroiliac joint. Sacroiliac joint osteoarthritis or arthropathy is one of the most frequently overlooked conditions, which are treated incorrectly or not at all in the long term – because their cause is not recognized.
Leading Medicine Guide: Whatever you call it: the underdiagnosed problem. Sufferers often go through an odyssey of back pain, visiting one specialist after another, and nobody can really help them. Sometimes the last resort is psychological treatment. Why is that?
Prof. Dr Clément Werner: Basically, the reasons are almost trivial: spinal specialists only cover the area up to the sacrum. The sacroiliac joint is not discussed during medical studies, nor is it covered in specialist training. Young doctors do not learn about the typical pain patterns and are not familiar with this specific phenomenon. The cause of the pain is assumed to lie in the spine, but that is not where it is.
Leading Medicine Guide: This pain phenomenon deep in the back has, so to speak, captivated you; you have studied it intensively and were able to learn a great deal about this particular joint through international further training and several fellowships in the USA.
Prof. Dr Clément Werner: In the USA, the approach to pelvic surgery is quite different; I learnt a great deal there about the sacroiliac joint complex. And there is also a different training system in the renowned hospitals and clinics; they take pride in passing on their knowledge. I don’t experience that here. I trained at the largest trauma center in the US and then at two spinal centers.
Leading Medicine Guide: And then you conducted research into a clear-cut procedure to reliably detect sacroiliac joint symptoms clinically.
Prof. Dr Clément Werner: The complex anatomy and the varied pain patterns often lead to misinterpretation. Unfortunately, patients with SIJ disorders exhibit a very broad pain pattern, which often leads to inappropriate diagnoses and treatments. X-rays do not provide clear evidence of sacroiliac arthropathy. All diagnostic tests in use to date have only limited diagnostic value. Based on existing approaches, we have therefore developed a new test, the PSIS distraction test – posterior superior iliac spine. It is, in principle, quite simple, but has reliable clinical significance. Patients, standing or lying on their stomachs, are asked which specific, central or lateral forces trigger pain or cause it to increase. The test is considered positive if it reproduces the typical pain. Compared with classic provocation tests, the PSIS distraction test demonstrates superior accuracy of 94 per cent.
PSIS distraction test
Leading Medicine Guide: Are there specific pain symptoms that patients might be able to recognize themselves to determine whether they are suffering from sacroiliac joint problems?
Prof. Dr Clément Werner: There are criteria such as morning stiffness lasting longer than 30 minutes; relief of pain through movement, but not at rest; waking up during the second half of the night due to back pain; alternating pain in the buttocks; a pulling pain running down the side of the thigh to the knee or the lateral calf.
Biosacral arthropathy with characteristic involvement of the lateral knee joint
Leading Medicine Guide: There are now many osteopaths and physiotherapists who specialize in the sacroiliac joint and have developed numerous exercises for it. What is your view on this?
Prof. Dr Clément Werner: Treating sacroiliac joint blockages with physiotherapy or manual therapy is, of course, beneficial and does help for a certain period of time or in specific anatomical cases – unfortunately, not for everyone. For example, a chronically unstable sacroiliac joint cannot be treated in this way. However, specific stretching and strengthening exercises, an ergonomically correct sitting posture, avoiding certain movements and, if necessary, painkillers can help.
Leading Medicine Guide: Unfortunately, we know from those affected that the pain is quite persistent. Why is that?
Prof. Dr Clément Werner: We doctors still have a lot to discover in this regard. It is probably because the entire ligamentous apparatus surrounding the sacroiliac joint or joints is irritated and inflamed. Healing takes time; the body must also be given the opportunity to do so.
Left: hidden cause of SI joint arthropathy. Top right: coxarthrosis, air in the SI joint, mammillary body
Leading Medicine Guide: With the PSIS test, you can accurately diagnose sacroiliac pain. What happens next for people who have finally received a diagnosis for their previously unexplained back pain?
Prof. Dr Clément Werner: Acute pain is initially treated with cold therapy, then heat therapy and painkillers. If the patient has legs of different lengths – which is not at all uncommon – then special shoes are prescribed. Physiotherapy and specific stretching exercises provide relief. If the pain pattern does not change, we administer a depot cortisone injection plus a local anesthetic into the joint and the ligamentous apparatus. This soothes the entire affected area. Around 80 per cent of patients are then symptom-free and only return after a few years. Unfortunately, we see 20 per cent of those affected again soon; these are usually the ones with an unstable joint.
Leading Medicine Guide: To this end, you developed a special implant many years ago, which is inserted via a minimally invasive procedure. You have already performed over 500 SI joint operations and, thanks to your pioneering work, are a sought-after speaker at scientific conferences.
Prof. Dr Clément Werner: You have to imagine it like the dowels used by a well-known Swedish furniture brand; it’s the same principle. We insert three of these, which then fuse with the sacrum and ilium to stabilize the joint. In the patients treated, the pain level usually drops from around 8 to around 2.5 on a scale after the procedure. In addition, I often go in and ablate certain pain fibers; this has a lasting effect and we find that we achieve better results with it.
Example of a sacroiliac joint fusion
Leading Medicine Guide: You share your extensive knowledge of the sacroiliac joint and its osteoarthritis or arthropathy with joy and enthusiasm in training courses. In the German-speaking world, you are regarded, so to speak, as the ‘pope’ of the sacroiliac joint.
Prof. Dr. med. Clément Werner: The anatomy of the SIJ is very complex, and SIJ arthropathy does not fall within the normal remit of spinal specialists, orthopedic surgeons, rheumatologists or chiropractors. This subject area should therefore be taught as part of specialist orthopedic training, and young doctors need to familiarize themselves with the typical clinical picture and the appropriate treatment options. Only in this way can many people suffering from deep-seated back pain be helped.
Professor Werner, thank you for these extremely interesting insights into your field of expertise. The profile page on the Leading Medicine Guide provides direct contact details for our specialist.
