Kei Masani

The fine art of standing 

Injury or disease can rob people of the ability to stand and walk on their own. Can scientists create a device, as simple to put on as a pair of trousers that would allow people to stand or even walk again? Developing such a device is a major engineering challenge―one that Dr. Kei Masani is on the way to solving.

An expert in human motor control, Dr. Masani, a Toronto Rehab Scientist, is exploring the potential of a technology called functional electrical stimulation ―or FES― which stimulates people’s nerves with tiny electrical impulses.

“By stimulating the correct nerves in the correct order, we can cause the patient to perform a range of actions such as grasping an object or standing up,” explains Dr. Masani. “FES is a very powerful technique.”

FES has enormous potential for people with paraplegia. It would allow some people with paraplegia to stand up, perform “hands-free” standing, and sit down. Standing not only increases the ability to perform tasks but also has important health benefits. It keeps bones strong, reduces fragility fractures and pressure sores, and regulates blood pressure and digestion. This is why people with spinal cord injuries need to stand regularly, using standing frames, braces, walkers and other aids.

Before FES can be put into wide use, Dr. Masani and colleagues need to answer some key questions, such as: exactly which muscles are needed to maintain balance during standing? What order should the muscles contract in? And can FES produce muscle contractions that are strong enough and quick enough to compensate for unexpected disturbances during standing?

To answer these and other questions, Dr. Masani is conducting experiments with healthy subjects

“We need to learn much more about how people maintain balance while standing. Animals can stand and walk almost from birth. Humans, however, take years to learn how to stand or walk. We are bipeds, and keeping our balance while walking on two feet is not easy. My research goal is to understand exactly how we do it..

“Robots use motors to move,” Dr. Masani adds. “Scientists can control motor force very precisely. However, human beings rely on muscles to stand and walk – and muscles cannot be controlled as precisely as motors, either by the brain itself, or by signals from an FES device. Yet, when using FES to help patients stand and walk without losing their balance, we need to control muscle force with great accuracy. Achieving this fine control is a major challenge, and one of the issues we’re working on at the moment.”

Until recently, there has been little research into how humans keep their balance. Dr. Masani is one of the few scientists applying research findings to improve rehabilitation techniques using FES.