What are robotic exoskeletons?
Author: Sharon Jang | Reviewer: Riley Louie | Published: 7 April 2021 | Updated: ~
Robotic exoskeletons (also known as powered gait orthoses) are wearable electromechanical devices that enhance movement of weak or paralyzed legs. They are electrically powered at the joints, allowing the hips, knees, and ankles to move. The greatest advantage exoskeletons have over passive orthotics or braces is that they are programmed to enable coordinated movement without much effort from the user. This is especially so since exoskeletons carry their own weight as well as that of the user. Movements that most exoskeletons assist include sit-to-stand and walking.
As of 2019, many different models of exoskeletons exist, and this number continues to grow as research and technology progresses. However, it is important to note that only three have been approved by the FDA for sale in North America and only two have been approved for home use, while the other is only approved for research and rehabilitation purposes. The two that are approved for home use are the ReWalk and the Indego, while the Ekso has been approved for research and rehabilitation purposes. The current models of exoskeletons have the ability to move from 0.2-2.6 km/hr, and weigh between 12-38 kg.
Exoskeletons are slowly moving into the community. Currently, most models can only move over flat, smooth surfaces. However, some can go up inclines. Moreover, newer models have the added function of enabling the user to sit in or wheel a wheelchair without having to take off the device. These features can increase the independence of people with SCI and enable/enhance the performance of activities such as standing, walking, and climbing stairs. However, these devices are still expensive, ranging from $70,000-120,000 USD.
In deciding if robotic exoskeletons are an appropriate option for you, a health care provider will perform an assessment where they account for factors such as your level of injury, risk for falls and fractures, and range of movement. Once exoskeletons are deemed appropriate, training will be required to learn how to properly use the device. A physiotherapist or caregiver may help you put on and take off the device. Generally, the feet are placed on footplates and the torso, hips, and legs are strapped into the exoskeleton. Some models extend upwards to include a backpack-like structure, which offers more trunk support and contains the computer and battery. Other models are secured only at the waist and below. In addition, some models can be programmed externally using a tablet. A pair of forearm crutches or a walker is often used to maintain balance. As someone with SCI walks, the built-in sensors and motorized joints (hip, knee, and/or ankle) constantly accommodate to encourage a rhythmic walking pattern. When the individual improves their own walking function and requires less assistance, the exoskeleton can be adjusted to provide less support.
