Therapy Robots

The term “rehabilitation robot” has been around for a good 30 years, when it was first applied to assistive motorized devices that performed tasks of daily living for people with physical impairments.

There are approximately 600,000 new cases of stroke in the United States every year. The “gray­ing” of the population is even more pronounced in countries such as Japan. Patients undergo physical therapy to restore lost function. The therapy tends to be repetitive, and evidence suggests that the dura­tion, intensity, and quality of therapy all play a role in recovery. Although functional gains remain small, the potential of machines assisting in therapy is enor­mous. These machines are ideally suited to the rig­orous and repetitive nature of therapy. The following paragraphs describe some of the devices that are cur­rently on the market.

Manually assisted treadmill walking is commonly used for regular therapy for patients with neuromus­cular impairments. This type of therapy is performed with some type of harness system that supports the patient's weight. There are two main limitations to this type of therapy: It is labor-intensive, as it requires two therapists to move the patient's legs, which causes therapist fatigue and back pain due to awkward the ergonomic positions. Second, manual therapy lacks repeatability and a way to objectively measure per­formance. The Locomat (Hocoma AG, Volketswil, Switzerland) is a bilateral robotic gait trainer that is used along with a weight-supported system.

InMotion Robots (Interactive Motion Technologies, Inc., Cambridge, MA) are a suite of table-mounted robotic systems that provide therapy for the shoulder, elbow, wrist, hand, and overground ankle training. The robots are combined with a video screen to pro­vide a fun and therapeutic environment for exercise. These robots can be programmed to vary the relative effort between the user and the robot. If, for instance, the user is weak, the robot can do most of the work. As the patient gains strength, the robot's effort can be decreased appropriately. The InMotion system has been developed over the last 15 years, and its strength is that it offers a low impedance system so that the effect of the robot can be imperceptible to the user. It is primarily used for stroke and other neurological disorders.

Another upper extremity robotic-based rehabilita­tion system is the REO made by Motorika, Ltd., a com­pany established in 2004. REO is an upper extremity device made to apply robotic technology to meet the therapeutic needs of stroke patients. It offers efficient repetitive training activities. “REO Therapy” actively engages a patient in repetitive exercises to improve arm function, while therapists benefit from patient progress monitoring and practice efficiency. A video screen accompanies the device to provide progress and visual stimulation during exercise. The company also offers a REO Ambulator for lower extremities that is a robotic gait trainer similar to the Locomat. It has been used for a few years in rehabilitation clinics; however, there is still insufficient data to support its findings.

Other robotic therapy devices being developed for the upper extremity include the T-WREX (27), iMove Reacher (iMove Support, Hengelo, Netherlands), and McArm (Focal Revalidatietechniek, Netherlands), HapticMASTER (Moog FCS, Netherlands). A lower extremity device under development is KineAssist (Chicago P, Chicago, IL).