A robot suit developed in Japan and engineered to allow paraplegics to regain a certain mobility and activity level, has reportedly shown promising results during clinical trials at the university hospital Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil.
The robot suit has been tested by a team at the university hospital since 2011, according to a news story in RUBIN Science Magazine. The suit, called HAL (Hybrid Assistive Limb), has been in clinical trials carried out by the team at the Centre for Neurorobotic Movement Training (Zentrum für Neurorobotales Bewegungstraining, ZNB) in Bochum, which was founded specifically for the purpose of testing the technology.
The robot is engineered to detect a paralyzed patient’s signals to the muscle through sensors attached to the patient’s skin, which in turn sets the device’s motors in the pelvic and knee-joint regions in motion.
See a video of HAL
Thomas Schildhauer, professor, team leader and medical director at Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil, explains that, “This is how we wish to activate and foster the residual function of the muscles and, ultimately, to help the patients attain better activity levels.”
Schildhauer adds that the extent that HAL therapy will enable a paralyzed patient to walk unaided depends upon the type of the injury, since “the robot does not repair the injured nerve structures in the spine; it merely ensures that the weakened signals reach the leg. Our aim is to optimize this loop. The residual functions that the patient possesses are to be strengthened.”
The news story adds that this does not mean that the patient will be able to walk normally after the therapy is completed.
The news story reports that each training session begins with physiotherapy exercises meant to improve the patient’s agility. Subsequently, the therapist wires up the patient and places the patient into the robot suit. Initially, the treadmill session is conducted for about 5 to 10 minutes, and later can go up to an hour. The duration is determined by the stability of the patient’s cardiovascular system, the strength of the muscles, and the injuries or respective diseases the patient has, the story says. The robot can be customized to each patient and support movements to a greater or lesser extent. The training level is regulated through a computer.
According to the story, Schildhauer’s team uses the clinical trials at the ZNB to determine a variety of the technology’s facets, including how much training is required and how long the training effects will or will not last. The team has reportedly implemented a 3-month training cycle, with five training sessions per week. A control group in Japan undergoes only eight training sessions, the story notes. The story goes on to maintain that a comparison of the trials in Japan and those in Bochum suggests that improved results may stem from an intense training program during a period of 3 months.
Schildhauer states that the team’s patients attain activity levels that improve their ability to navigate their daily life and surroundings, allowing them to continue to train their movement routine everyday. However, since only 14 patients in all age groups completed training at the ZNB to date, the team will need to conduct additional trials in order to verify the results. The story points out that after the training sessions with the robot suit, muscle activity and agility improved in all patients.
The trials’ results have allowed ZNB to receive comprehensive financial support that is now being used to expand the center; including the purchase of new robots, as well as a branch off into new research areas. The story notes that to date, the center has been studying robots built to aid in both lower extremities. Future studies are slated to explore applications for one single leg or one single arm. These specific robot suits, the story says, are intended for patients who have sustained a stroke of have multiple sclerosis (MS).
The story states that the long-term objective is to launch HAL in the German market to allow it to be used by as many patients as possible.
Source: RUBIN Science Magazine, RURH-Universität Bochum