Harvard researchers develop soft coat to help stroke patients walk

In the United States, stroke is the leading cause of long-term severe disability. About 17 million people suffer from a stroke each year, and eight out of every 10 stroke survivors are left with paraplegia, a typical type of paralysis of limbs and facial muscles affected. This type of paralysis usually leads to severe walking difficulties, loss of balance, and an increased risk of falls.

Paraplegia can also lead to muscle fatigue, which can quickly occur during exercise, often preventing people with this condition from completing their basic routine. Researchers at Harvard University believe they have a new system to help stroke patients recover. This soft coat was developed by mechanical and electrical engineers at Harvard University and costume designers and neurorehabilitation experts.

The soft, mechanical coat is attached to an external battery and motor, and tests have shown that stroke patients can significantly improve their biogae function while walking on a treadmill. The team took a critical step in turning their equipment into a rehabilitation strategy. They have been using a tieless protective suit version with batteries and electric motors.

So far, the new system has been tested in six patients with post-stroke paraplegia and found that soft outer clothing significantly improves their walking speed by an average of 0.14 m/s. One of them could walk as fast as 0.28 m/s, and they could walk an average of 32 meters in six minutes over those who did not use the system.

The mechanical outerwear used in the study weighed less than 5 kg and targeted the limbs of stroke survivors at different stages of the gait cycle. The suit is fully removable, battery-powered and started by an actuator unit worn on the hips. It is able to deliver mechanical power to the ankle through a cable-based mechanism, and the cable slots on other parts of the outer sportswear to the body through lightweight functional textiles. The user wears a mechanical coat only on the damaged side. In the tests, the team said, they saw significant and timely improvements in walking speed and distance when the mechanical coat was energized.

Harvard researchers develop soft coat to help stroke patients walk