Stroke

A stroke occurs when a part of the brain doesn’t get enough oxygenated blood, killing the affected brain cells. It can occur in one of two ways: (1) a clot in a brain artery blocks the flow of the blood, or (2) a blood vessel feeding the brain ruptures, causing the blood to leak out of the vessel.

According to the American Heart Association, about 795,000 Americans have a stroke each year. Although it can occur at any age, risk greatly increases after 60. Stroke is the third leading cause of death in the U.S. and a leading cause of serious, long-term disability.

Surviving a Stroke

The National Institute of Neurological Disorders and Stroke estimates about 4 million Americans are stroke survivors. The degree of recovery is dependent upon a number of factors, like the area of the brain affected, the amount of brain damage and the overall health of the patient. Only about 10 percent of stroke patients have a near complete recovery. 25 percent have some kind of lasting minor impairment. The majority of stroke survivors (40 percent) have moderate to severe impairments and need some degree of assistance or special care. About 10 percent require intensive care in a nursing home or long-term care facility.

Rehabilitation

Researchers estimate about 85 percent of stroke patients have some level of upper extremity impairment. During rehabilitation, doctors and therapists try to help recovering patients relearn lost skills or find new ways to do things to compensate for limitations.

One system being used for upper extremity rehabilitation is called the Myomo® (my own motion) NeuroRobotic System. It’s a type of robotic brace developed by scientists at MIT and Harvard Medical School. The system uses residual electrical signals from the arm muscles to improve upper limb movement. It uses an EMG (ElectroMyoGram) sensor, special software and a wearable robotic device that looks like an arm/elbow brace.

During a therapy session, when the patient attempts to move his/her arm, the EMG senses the electrical activity in the muscles. The signal information is sent to a processor, which analyzes the strength of the signal, then the information is forwarded to the robotic device, which makes the arm bend in the desired direction.

Sharon Nicoll, OTA/L, Occupational Therapist with Eastern Rehabilitation Network in East Hartford, CT, says the system works like power steering in a car, amplifying weak muscle electrical signals, and then telling the robotic portion of the system to “bend” the arm. By repeating the action over and over, the nerve and motor pathways are eventually re-educated and strengthened. With continued therapy, the system aims to restore natural movement and improve range of motion. Most importantly, the Myomo appears to improve function even for patients who had a stroke many years ago.

Nicoll says the Myomo system isn’t for everyone. It won’t work for patients who have a rigid contracture (unmovable bend of the limb) or no detectable EMG signals.

For information about Myomo, go to:

Myomo

For information on stroke or stroke rehabilitation:

American Stroke Association National Institute of Neurological Disorders and Stroke National Stroke Association