White Robotic Arm by Franck V. on Unsplash under Public Domain
What is rehabilitative robotics?
By: Katy Meier
For many of us, walking is a mindless task. However, that is not the case for all. In 2014, there were 46 million people living in the United States at the age of 65 and older who fit the criteria for the general category of “elderly”. An analysis conducted by the Population Reference Bureau estimates that this elderly population will exceed twice this amount by the year 2060
Partial Infographic from Federal Interagency Forum on Aging Related Statistics 2017
(Mather et al. 2015). Furthermore, the aging population is only a portion of society that experiences difficulties with mobility. When paraplegics and amputees are added into the equation then the number of people affected increases dramatically. While the large scale and severity of this problem may seem discouraging, hope is found in the emergence of a new field that mirrors technology only once known to superheroes. This new field is known as rehabilitative robotics. Though it may be hard to believe, the United States (US) military is the one to thank for pioneering the precursor to this field. Following the Civil War and World War I, the US saw a significant incline in amputations, however, it wasn’t until World War II that soldiers had reached the point to demand better prosthetic devices. It was at this point that the US military shifted some of their funding from weaponry to prosthetic research. This new funding allowed for lighter, more user friendly and technologically advanced prosthetics to be produced. Stemming from the principles of this research came a new study based on creating exoskeletal supportive devices that improved the average human strength (Dollar and Herr 2008). Taking this technology and adding an alternative motive of potential healthcare application created the broad but amazing field of rehabilitative robotics. The relevance of this discipline is universal, applicable to a variety of ailments and coming in the forms of limb prosthetics and even full body exoskeletons. Recently a full body exoskeleton known as the “human body posturizer”, abbreviated “HBP”, was designed specifically for the elderly (Verrusion et al. 2017). Although these full body human exoskeletons originated with the purpose of improving human strength for combat applications, this new direction of elderly application has the potential of revolutionizing reality. It would do so by catering to a commercial audience that needs help with a product that has proved promising in various studies.
Why are exoskeletons needed?
Even though many people dream of a life of being waited on, never having to lift a finger, it’s not as glorious as it sounds and can create more complications than one would think. Immobility can lead to an abundance of health problems externally and internally. Lack of resistance causes muscle mass to decrease and also impair blood flow. This can immediately be dangerous because slowed blood flow means that injuries are not healed as efficiently and organs are not receiving proper nutrients to complete assigned functions. In particular when the stomach receives improper blood flow it can lead to constipation which can ultimately end malnutrition (Lindgren et al. 2004). Unfortunately, the stomach is not the only organ affected by immobility, the skin is as well. Continual pressure in one area can degrade the skin creating an area of irritation and in worse cases open sores. These areas are referred to as pressure ulcers. If not treated properly, pressure ulcers will gradually worsen increasing the potential of infection and death. In a study conducted examining a total of 642 patients from 22 different hospitals in Iceland, there was a 9 percent prevalence rate of pressure sores, 81 percent of which were of those aged 70 years or more (Thoroddsen 1999). Furthermore, a prospective study in Sweden found that immobility was the largest risk factor in the development of pressure sores (Lindgren et al. 2004). However, not all adverse effects of immobility are biological; they can be psychological as well. Believed to be caused by sensory deprivation, lack of physical activity can cause depression as well as other mental changes such as hallucinations (Harper and Lyles 1988). Thankfully, not all elderly people are completely immobile. Many solely struggle with balance and strength. While this may seem better than never being able to move, this struggle can lead to falls which have arguably worse consequences. In 2009, approximately 30 percent of the falls in the US elderly population resulted in moderate to severe injuries including fractures, head trauma and open cuts (Verrusio et al. 2017). Imagine how different the world’s perspective of the elderly would be if these problems didn’t exist, or at the very least were decreased. Current technology is paving that path and recent research is promising.
How does the exoskeleton work?
Exoskeletons are a full body sized robot that works in conjunction with the user. They use a combination of passive and active movement to assist the user in the assigned task,
Characteristics of exoskeleton human body posturizer (from Verrusio et al. 2017)
which is in most cases movement (Marinov 2017). A recently developed exoskeleton designed for the elderly and growing in popularity due to its compactness is known as the “human body posturizer” (HBP). HBP is a fully mobile brace that is composed of four simple components constructed using light hypoallergenic and waterproof material allowing the device to be worn directly on the skin and used in water (Verrusio et al. 2017). Of the four components, the first is placed on the back while the second is similar to a helmet and connects the elements from the waist up. The third element is placed near the tailbone to allow for assistance with thrusting movements. Finally, the fourth component is used to support the lower limbs (Verrusio et al. 2018). In total, these components weigh only about 3.3 pounds and can fit in a medium sized travel case (Verrusio et al. 2017).
What has current research found?
Exoskeletal research is still in its infancy, yet early results are promising. In particular, studies involving the human body posturizer have found that the product greatly reduces fall risk as well as lowers depression levels in elderly people. Both of these variables are major risk factors associated with the wellbeing of the aging population. In order to test the effect of the HBP on fall risk, the device was used experimentally by one group during exercise for one hour a week and then results were compared to another group that didn’t use the device but completed the same exercise routine. Both groups were objectively measured initially, midway through and at the end of the yearlong experiment using the Tinetti Gait and Balance Scale and a quality of life questionnaire. Research was also collected by having each subject keep a running record of any falls throughout the trial. Both groups began with similar baselines but in the end, the risk of falling was 68 percent less in the group that used the HBP while exercising. As exciting as these results are, more research is needed for definitive results especially since this study only included those with a medium fall risk as well as evaluated a small sample population of 150 people in Rome (Verrusio et al. 2017). An additional study conducted using the HBP examined its influence on depression in elderly patients. It was hypothesized that the device would decrease depression levels due to the stimulation the HBP causes in the pre-frontal cortex region of the brain and the fact that decreased pre-frontal cortex activity has been linked to depression. Luckily, the study supported this hypothesis, finding that final scores on the Geriatric Depression Scale in the group using the HBP decreased significantly more than final scores in the control group. However, it is important to keep in mind that this study only evaluated 20 patients all from the same Jewish nursing facility in Rome, meaning that these results cannot be generalized without further substantiation (Verrusio et al. 2018). These two studies provide hope for the future of rehabilitative robotics as well as support the potential benefit of clinical application of exoskeletons.
What are the limitations of Rehabilitative Robotics and what does the future hold?
As with most recent scientific movements, rehabilitative robotics has made many advancements yet can still continue to be improved. Challenges regarding efficiency, flexibility and affordability have yet to be overcome with many devices only able to support limited movements and be available to a limited audience due to price (Chen et al. 2016). While these factors limit commercial application now, it’s only a matter of time before the solutions are found and human exoskeletons are as common as canes. As someone who has first-hand witnessed the suffering aging causes through loved ones, my heart flutters with excitement thinking about the pain these devices can take away. Through the freedom of independence and comfort of stability, human exoskeletons have the potential to change the connotation of the word “elderly”.
References
Chen B, Ma H, Qin L, Gao F, Chan K, Law S, Qin L, Liao W. 2016. Recent developments and challenges of lower extremity exoskeletons. JOT. 5: pp. 26-37.
Dollar A, Herr H. 2008. Lower extremity exoskeletons and active orthoses: Challenges and state of the art. IEEE Transactions on Robotics. 24(1): pp. 144-158.
Harper C, Lyles Y. 1988. Physiology and complications of bed rest. J Am Geriatr Soc. 36(11):1047-1054.
Lindgren M, Unosson M, Fredrikson M, Ek A. 2004. Immobility – a major risk factor for the development of pressure ulcers among adult hospitalized patients: a prospective study. Scand J Caring Sci. 18(1): pp. 57-64.
Marinov B. 2017. Exoskeleton report. What is an exoskeleton? [accessed 2018 Sept. 16]. https://exoskeletonreport.com/what-is-an-exoskeleton/
Mather M, Jacobsen L, Pollard K. 2015. Aging in the United States. Population Bulletin. 70(2):1-19.
Thoroddsen A. 1999. Pressure sore prevalence: a national survey. J Clin Nurs. 8(2): pp. 170-179.
Verrusio W, Gianturco V, Cacciafesta M, Marigliano G, Troisi M, Ripani M. 2017. Fall prevention in the young old using an exoskeleton human body posturizer: a random controlled trial. Aging Clin Exp Red. 29(2): pp. 207-2014.
Verrusio W, Renzi A, Cecchetti F, Gaj F, Coi M, Ripani M, Cacciafesta M. 2018. The effect of physical training with the use of an exoskeleton on depression levels in institutionalized elderly patients: a pilot study. J Nutr Health Aging. pp. 1-4.