Demand for rehabilitation robotics increasing as population ages

Ljubljana, 3 January - Researchers of the University Rehabilitation Institute Soča have developed a robot to aid patients in training walking balance and coordination on a treadmill. Called the Balance Assessment Robot (BAR), it is intended for the rehabilitation of patients who have suffered central nervous system damage.

Using BAR, patients can train symmetry, swing and dynamic balance, the three most important aspects of walking. The robot is particularly useful in stoke rehabilitation, says the head of the institute's R&D department Zlatko Matjačić.

According to Matjačić, the institute's coordinator in the EU project BALANCE, rehabilitation robotics is on the upswing. The increasing number of older people is driving demand for rehabilitation and technologies such as BAR.

Device is put around pelvis and monitors patent's movement

The robot, which is equipped with sensors monitoring the patients's movement, is put around the patient's pelvis. It has six degrees of freedom, just like the human pelvis. This means that it can move freely in the forward-backward, left-right and up-down directions, and rotate around these three axes at the same time.

When the device is attached to a patient who walks on a treadmill, it provides support just like a therapist would. Therapeutists usually have 20 to 30 years of experience and have a better feel than the device, but the problem is that they get tired quickly.

An added value of the robot is that the patient can make significantly more repetitions and these repetitions are very precise, Matjačić said.

Studies have shown that the fitness and functional ability of patients after therapy with BAR improves strongly compared to institutional rehabilitation.

Robot works in different modes

The robot can work in different modes depending on the type of injury, the goal of therapy, and the patient's ability. When the goal of therapy is to maintain dynamic balance, the robot does not influence the patient's movement, it only follows them. The idea is to make movement as natural as possible.

During stroke rehabilitation, the focus is on walking symmetry. After stroke, patients mostly use the healthy leg and avoid using the affected, hemiparetic leg. Such walking can wear down the locomotor system, it reduces stability, and it increases the risk of a fall.

In such cases, the device applies corrective force. When the patient stands on the right, affected leg, the device pushes the patient slightly to the right, like a therapeutists would. This prevents the patient from switching the weight back to the left, healthy leg, so quickly.

One training session takes half an hour to an hour, depending on the patient's ability and stamina, and includes around 1,000 steps. "Around 40,000 steps are made in 20 to 40 sessions with different intensity of interventions, swings or thrusts. The results of neurophysiological studies show that motoric learning starts after 1,000 or more repetitions."

From patent to commercial product

The development of the robot has been completed in the technical sense. Procedures are currently ongoing to obtain European and US patents. The institute is also discussing potential cooperation with several producers of rehabilitation robotics.

If the device cannot be developed into a commercial product, it will be impossible to use it in clinical practice as therapists can only use devices which are properly certified, Matjačić explained.

The robot and the institute are at the cutting edge in the field of rehabilitation at the global scale. The robot has been developed as part of several projects, including the EU project BALANCE, which aims at understanding and resolving the problem of balance by means of robotics.

The robot has received international media coverage, with Euronews running a story about it in its science and technology section Futuris.

Research and development department

The institute's research and development department, which currently employs four PhD holders, prepares, manages and implements research projects in rehabilitation engineering, supports research projects in physical medicine and rehabilitation, and carries out laboratory research in kinesiology and biomechanical dynamometry.