María José Enciso López, student at the Center of Applied Physics and Advanced Technology (CFATA) of the National Autonomous University of Mexico (UNAM), develops a damping orthosis for variable friction for the management of tremors caused by Parkinson’s disease.

Enciso López explained that this technological development allows tremors to be reduced in a static way, through a polymer designed to allow only passing low frequencies and a dynamic system, which measures its frequency and offers a variable coefficient of friction over the displacement.

“As part of the research, we designed a mathematical model to describe the biomechanical dynamics of limbs and simulations to validate with an oscillatory input in a prototype. We made an analysis of the shape and movement of the hand for an ergonomic and functional design. Through the software SolidWorks, we did the design, made up of a ring, a mitten and a bracelet; which were printed in 3D with polylactic acid (PLA), as it is a biocompatible and easy to use thermoplastic. They are joined together by a flexible piece made of an elastic polymer for a biomechanical reduction, cast in a mold printed on PLA. In the simulations, we could identify that the tremors are reduced up to 90 percent in its amplitude, which would allow the patient to recover some autonomy in their activities such as taking things or getting dressed.”

The CFATA researcher and project advisor, Dr. Ángel Luis Rodríguez Morales, pointed out that this project has taken around two years and began with the characterization of patients with Parkinson’s, which was carried out through an agreement with the Institute of Neurobiology of the UNAM.

“This allowed us to take videos of tremors to characterize the joints where they were most present and work on the orthosis. We already have the conceptual design and we finish the simulations. We are in the stages of manufacturing the prototype and conducting tests with patients, that is placing it, leaving it for a few days, as well as evaluating how much the orthosis can be adapted and the tremors reduced in a given period.”

He stressed that they are negotiating to collaborate with the Micro and Nanotechnology Research Center (MICRONA) to generate more reliable technological development.

“Dr. Agustín Leobardo Herrera May is a developer of microelectromechanical systems (MEMS) at MICRONA, and has a research to more accurately measure the frequency and amplitude of tremors in real time. That information can be useful because the controller uses that data to make the filtering.”

María José Enciso López, said that Parkinson’s disease is a neurodegenerative disorder that starts from a chemical imbalance in the body, where it stops generating the dopamine that is necessary for the control of movement.

“Currently, treatments for the disease consist of drugs that are not totally effective and can generate side effects, ranging from vomiting and dizziness to something more serious, such as dementia or memory loss. The other option is the orthosis, or external devices, which allow the control of movements. Those currently on the market are of constant friction; they make movement difficult and immobilize the limb of the patient, who has to make a greater effort to take a glass or brush his teeth, in addition to generating muscle fatigue or injuries. What we are developing is a variable friction orthosis, in such a way that it can adapt to the tremors of the patient and, by means of sensors, detect the movement of the muscle, to differentiate the pathological movement from the normal one“.

The variable friction damping orthosis for the management of tremors caused by Parkinson’s disease of CFATA was selected at the Expociencias Bajío 2018 to represent Queretaro at the National Expociencias, which will be held in Morelia, Michoacán, at the end of November.

 

Source: Agencia ID