South Ural State University
Chelyabinsk, Russia

Anew device developed at South Ural State University is unlike analogous devices in that it involves all joints of a lower limb. The patented technology can be used for rehabilitation after serious injuries or for teaching children with infantile cerebral palsy to walk.

The work on the device has been carried out during the last four years. A team of scientists from SUSU School of Electrical Engineering and Computer Science and Institute of Sport, Tourism, and Service is creating a prototype model for testing.

A patient’s leg is fixed in the device. After that, a forward movement is carried out during which it affects the ankle-joint in two planes. (Credit: Viktoriya Matvejchuk)

“We have developed a mechatronic rehabilitation device for people with lower limbs injuries. This technology has a name of Continuous Passive Motion. Our aim is to make one’s lower limb again movable as in a postsurgical period a man’s organism undergoes different processes which prevent it,” says Aleksey Petrov, an author of the project and a teacher in SUSU’s Department of Electronic and Computing Machines.

Similar existing devices can be used only in cases of rehabilitation after knee joint or hip joint injuries. The new device also involves an ankle joint, which enables all of the joints of lower limb to be part of the recovery process. Moreover, the device also mimics walking — a very important function for formation of correct movement pattern. This function allows a patient to maintain the habit of walking during serious injuries. The device can also be used to teach children with infantile cerebral palsy how to walk correctly.

Rehabilitation with the device must begin from the second day after the surgery. A patient’s leg is fixed in the device and then a forward movement is made, affecting the ankle joint in two planes. Control of the limb is carried out with the help of rotating engines that transmit a rotation to system and lead to changing of the positions. A patient’s leg is fixed into a mechatronic device with the help of flexible suspension. The position of a leg is changed by means of shifting system elements.

“Our development is applied in a post-surgery period of rehabilitation after injuries or surgeries of ankle joints, hip joints, knee joints, or joint enlargements as well as for complex rehabilitation of patients with ICP,” says Aleksey Aleksandrovich. In this device, construction is different from constructions of analogous devices, which has a number of advantages, among them is a simplicity of limb fixation. Moreover, one of the main peculiarities of this construction is a combination of a joint spinning axis. Thanks to this, we can settle a precise path of motion and teach the patients to walk. Analogous devices in this case are less precise and they do not give a possibility of maximum correct control.”

A paper was published in the journal Man. Sport. Medicine. It describes the process of development of the device for patients’ rehabilitation after cerebral accidents by means of applying a “mirror” technology simulating the affected part of the body with the help of a healthy part by means of artificial visual feedback.

In March 2018, a paper was published in the Scopus citation database (here ). It covers the usage of this device for training professional skiers. An application of the device includes enhancing sports performance. This device helps to work out a stereotype of step position. In this case, its usage contributes to optimization of ski techniques and, as a result, to improve sport scores by means of innovative methods of training.

This article was written by Viktoriya Matvejchuk for South Ural State University Chelyabinsk, Russia.