Entirely unexpected

to HFU News

How exactly do you measure muscle tension? That's what a research project at Furtwangen University is investigating.

Physiotherapy: Interdisciplinary cooperation in basic research on muscle tension

In the comparatively young research field of physiotherapy, surprises are not unusual. This was the experience of Professor Dr Angela Dieterich, who, as she herself says, followed the "usual career path" – training as a physiotherapist, treating patients, running her own practice. But at some point, this was not enough. Dieterich came across the case of a young patient whose symptoms raised questions – questions for which there was no answer. In the process of research involving the basic principles and assumptions of physical therapy, Professor Dieterich discovered, "This is my thing." She decided to take the academic route, specialising in ultrasound techniques that could be used to map how muscles work – how a healthy muscle differs from one restricted by pain. Or at least that was the plan. "Instead, one of my studies showed the exact opposite of what we had suspected," she recalls with a laugh. Female patients with serious neck pain that had lasted for years were compared with symptom-free women of the same age. Result – virtually no difference in muscle stiffness could be detected. "That was a slap in the face," Dieterich says. But for her, all the more incentive to ask fundamental questions – with such a result, how is it that physiotherapists can nevertheless "palpate" tension and painful areas, i.e., feel them with the palms of their hands? This is what happens in clinical treatment, as Dieterich knows.

Meanwhile, the scientist is uncovering the secrets of muscles, quite literally at a deeper level. Through the process of elastography, or more precisely, shear wave elastography, every muscle fibre can now be observed. "It works like dropping a stone in water," Dieterich explains. "An electrical impulse is given, which then spreads out in waves in the tissue. After all, our body is really just water, with a few separating layers." This reaction is precisely what the "Can muscle tension be measured?" project, which Professor Dieterich has been researching for the last year, is all about. "It's amazing how underrated research in physical therapy is," she says. She is often asked whether her research involves developing new exercises for patients. Instead, Dieterich heads up an innovative research project involving an interdisciplinary group of specialists. Working together with Dr Leonardo Gizzi and Professor Dr Oliver Röhrle from the Institute for Modelling and Simulation of Biomechanical Systems at the University of Stuttgart, her HFU colleague Professor Dr Katrin Skerl as a specialist in high-resolution myography procedures, and research assistants, Dieterich is collecting "huge amounts of data." "I love working with so many tech-savvy people," she enthuses. Professor Dr Matthias Kohl of the Faculty of Medical and Life Sciences at HFU is also involved in the project - as an expert in precision medicine diagnostics, he compiles statistics from the data collected.

Although Professor Dr Dieterich says she is now cautious with assumptions and expectations, the project does reveal a previously largely unknown phenomenon – muscles also work "transversely," that is, in the opposite direction to the actual direction of the fibres. "This is demonstrated by the fact that muscle areas are already activated before the electrical stimulus arrives," Dieterich says. These transverse force transmissions could be a small part of the solution to all the puzzles that we have encountered. "Physiotherapists also palpate transversely, rather than along the muscle fibres," Dieterich reflects. Will she be able to prove this effect using the high-resolution imaging techniques? Well, one thing is certain, "Our body has plenty of surprises in store!"

Professor Dieterich has set up an Instagram channel to make her research accessible to the public: @muscletension.measure. Here the research team shows how the project is developing. This fascinating topic will also be presented at a health symposium hosted by Furtwangen University in Freiburg in September.