Algorithms for Old Age: In the Mobility Lab at 70+

Our society is aging rapidly, which makes it even more surprising that research in geriatric medicine is still in its infancy. Physicians and technicians of the Department of Geriatric Medicine at RWTH Aachen University and the Franziskushospital Aachen have now set up a Mobility Lab to help elderly patients – and to collect reliable data.

Alexandra Wolters | August 2018
Marcus Simaitis

The new Mobility Lab at Franziskushospital Aachen: Body-mounted markers allow the measurement of mobility, motor skills, and strength of the patients.

Wolfgang Wallraff has always enjoyed riding his bike – to the bakery, the public pool, or the farmer’s market. But then, the 75-year-old retired physics professor hit a curb. He fell, injured his hip, and was admitted to the Department of Internal Medicine and Geriatrics at the Franziskushospital – to quite literally get back on his feet. To this end, he has been assigned to the Mobility Lab, a new facility developed and recently set up by Cornelius Bollheimer, the director of the clinic and head of the Department of Geriatric Medicine and his fellow researchers. Here, the team measures and analyzes mobility, motor skills, and strength, as well as the sense of balance and response capacity of elderly patients. First of all, they determine the patients’ frailty and risk of falling, before putting together the right exercises and tools to improve their mobility and prevent falls. “On top of that, we are planning to use the measured values to create a comprehensive biomechanical database, develop algorithms, and lay the foundation for sound clinical studies,” explains Dr. Bollheimer, who - in general - assigns patients from about 70 years of age to geriatric medicine, based on  individual assessments. The 51-year-old professor is all keen on advancing research in this medical field.

The Robert Bosch Stiftung shares his goal, which is why the Foundation supports Dr. Bollheimer’s Department of Geriatric Medicine at the University Hospital of RWTH Aachen with 1.25 million euros. By 2020, the Foundation will provide a total of almost four million euros for the creation of three departments of geriatric medicine. Although the demographic change will entail a significant increase in the number of elderly patients, the respective university departments are still rare in Germany. “Other medical fields seem more attractive and appeal more to the med school students.” Dr. Bollheimer knows from his own experience that geriatric medicine is not an easy field: In old age, people and their health issues are much more heterogeneous and complex than, for instance, in the case of children. “But it’s this individuality that makes working with elderly patients particularly interesting,” he says enthusiastically advertising his speciality.

Marcus Simaitis

Wolfgang Wallraff and physical therapist Laura Schmidt at the Mobility Lab: The infrared cameras measure his position from different perspectives with the help of the reflecting markers.

A gym full of cameras and computers

The Mobility Lab at Aachen’s Franziskushospital is part of the interdisciplinary research and practical work of Dr. Bollheimer’s team of physicians, physical therapists, technicians, and engineers. At first glance, the lab looks like a small gym rented out to a software startup. A sand-colored walking track crosses the blue linoleum floor; it is equipped with various, almost invisible, plates to measure impact. Desks with computers and screens are set up at one end of the track. At the other end is a state-of-the-art treadmill with pressure sensors that would be the envy of most gyms. “The best thing about it is that special applications displayed on the screen make patients walk through virtual-reality obstacle courses,” explains João Batista. A physical therapist and health technician, Mr. Batista is the head of the Mobility Lab at Dr. Bollheimer’s Department of Geriatric Medicine.

To start off, he has put an easy route on the screen for Wolfgang Wallraff. Nevertheless, the 75-year-old is caught by surprise by the first tree trunk lying across the forest path he is navigating. “If it had been real, you probably would have stumbled. Try to lift your foot in time,” Mr. Batista encourages his patient. The Brazilian movement specialist has tried out the application himself and knows how difficult it can be to respond early enough.

The infrared cameras see it all

Mr. Wallraff is fascinated by the link between medicine and technology. The retired physics professor wants to know in detail how the spherical markers work that physical therapist Laura Schmidt attaches to him. She points to the ten infrared cameras mounted on the walls just below the white ceiling panels. “We use these to measure the positions of the reflecting markers from different perspectives, thus measuring a patient’s movements.” The data is stored on a computer, analyzed, and visualized on a big wall-mounted screen as a movement diagram with colored stick figures and dots. “This model allows us to see exactly a person’s body posture—as well as a potential malposition or irregularity,” explains Mr. Batista. The analysis of Mr. Wallraff’s movements shows that on the track his body control with a wheeled walker is good, but that he has problems getting up from a chair. Furthermore, he may be physically weaker than other people of his age.

These comparisons, calculations, and interpretations are still tricky as there is not enough reliable and meaningful data. “Data collection and research in geriatric medicine have previously taken a back seat,” says Dr. Bollheimer. To this day, for instance, many mobility and balance tests for the elderly are hardly standardized. So the interpretation of results still depends too much on the individual physician’s perception, he says, describing one of the current problems in his field.

Wheeled walkers – help or hindrance?

There is also not enough knowledge about the effectiveness of technical aids in geriatric medicine. Although in use for years, the benefits and effects of wheeled walkers have never been fully researched. Most of today’s walkers neither feature springs nor can they be individually adjusted. Hardly anybody is able to turn with them in a confined space, such as a bathroom, or walk backwards. “To be honest, we can’t even say if walkers really improve people’s mobility or do quite the opposite, because they actually cause falls.” This is the kind of study Dr. Bollheimer and his team want to conduct in their Mobility Lab—driven by the overarching goal to improve care for the elderly.

To be honest, we can’t even say if walkers really improve people’s mobility or do quite the opposite, because they actually cause falls.

This goal is also the motivation behind other projects the Aachen-based team is pursuing, such as the development of small, easy-to-use sensors that will eventually allow family physicians to reliably measure a patient’s mobility. Another project is the contactless measurement of vital parameters: The team can already permanently control their patients’ heart and respiration rates via near-infrared light, with no visible light or inconvenient wires.

Cornelius Bollheimer is thrilled about the interlinking of medicine and technology, which is why he appreciates Aachen, a location with many engineers. “What we are creating here is an interdisciplinary network consisting of technicians, physicians, and other health experts. And we try to get everyone excited about geriatric medicine,” says Dr. Bollheimer, adding with a wink: “Or at least very interested.”