The Rise of Physiotherapy Exoskeletons
What exactly is an Exoskeleton?
In nature, an exoskeleton is an external, rigid frame and shell that supports and protects an organism while enabling its normal range of motion. Invertebrate arthropods such as insects, arachnids, mollusks, and crustaceans all lack an internal skeleton (also called an endoskeleton) and instead possess exoskeletons that envelops their entire body.
In the fields of physiotherapy and biomedical engineering however, exoskeletons are a category of external, wearable devices that work with the user and augment their ability to perform physical tasks.
These devices work in tandem with the wearer and can either amplify the wearer's strength and endurance beyond their normal range (such as with a soldier or an industrial worker) or assist them in regaining their ability to move after suffering a debilitating illness or injury (such as patients recovering from a stroke or a car accident, or with permanent conditions including cerebral palsy, multiple sclerosis, and Parkinsons).
Exoskeletons are an rapidly advancing subcategory within robotics, seen as a game-changing way to interface humans and machines in order to improve our physical abilities and overcome our limits.
This ability of exoskeletons to restore freedom and autonomy to those who have partially lost mobility is the prime motivation in the development of these devices for use in physiotherapy, and each design takes a different approach to achieve this goal.
Exoskeletons can range from bulky full body suits that supports every limb and joint, to upper body frames that augments the user's back, arms, and hands, to lower limb systems that aids mobility, to even a single limb design.
Exoskeletons are usually made of a combination of materials such as steel, high-grade plastics, fiberglass or even carbon fiber. Depending on their purpose, they may be powered by a battery pack and equipped with sensors, actuators, and an onboard computer, or they can be entirely passive, using only mechanical pulleys, springs and dampers to boost the movement of the wearer.
How Do Exoskeletons Benefit The Wearer?
Different exoskeleton models offer varying levels of assistance. Some can move the wearer by detecting only nerve signals, suitable for users with severe paralysis. Others provide assistance only when the user exerts their own effort in movement.
This class of lightweight exoskeletons are essentially advanced braces that react to the wearer's movement and provide partial support and boost. This attribute, combined with its user-friendliness and lower cost makes it more accessible and ideal for the majority of patients that are able to walk somewhat and slowly but experience difficulties in movement due to weakness in their lower extremities from illness or injury. Seniors also benefit greatly from lightweight lower limb models to help them overcome osteoporosis and other age-related symptoms.
These users may be able to walk on their own but with some degree of difficulty. Conventionally, the use of a crutch or walker is required in their daily lives, thus occupying their hands and limiting their overall ability. Using a lightweight lower limb dermoskeleton such as Keeogo in their home allows them to walk in their normal posture and speed and frees up their hands to perform their daily tasks more naturally and improve their quality of life.
Bi-Temia's Keeogo was originally designed for the Canadian military but later commissioned by HealthCanada to be resdesigned as a lightweight and user-friendly walking assistance and physiotherapy device
Exoskeletons are also used by physiotherapists in the clinical setting to great success. Rather than manually supporting their patients' body and limbs during the rehabilitative training process, using an exoskeleton immediately gives their patients superior support, posture, positive feedback with every step, and perhaps most importantly, return some semblance of normalcy and hope for a better, speedier recovery to the wearer.
Gait training is the main rehabilitative therapy when it comes to lower limb exoskeletons and we will explore this in our next article.