By Polly Swingle, PT, GCS, CEEAA
The cerebrovascular accident (CVA), commonly known as a stroke, is now the fourth most common cause of death in the United States. Tragically, even those who survive a stroke often find their lives permanently altered, with lasting and often severe impairment. Approximately half of those who do survive a stroke are permanently disabled, and CVA are now the third largest cause of disability-adjusted life years in the developed world.
Understanding the scale, scope, and severity of post-stroke symptoms, and appreciating the emerging body of evidence about the most effective therapeutic protocols for stroke victims (including what treatments, exercises, and rehabilitative practices do and do not have a meaningful impact) are essential to understanding how to give stroke victims the best possible opportunity to recover functionality and improve their quality of life.
Impact and Impairment
CVA survivors typically face a number of mental and physical health challenges, from cognitive impairment to mobility and motor skills issues. A stroke typically leaves survivors with some or all of the following symptoms:
• Movement and function challenges
• Mobility limitations
• Balance difficulties
• Cognitive impairment
• Attention deficits
• Memory failures
• Chronic pain
• Sensation abnormalities
• Perception difficulties
• Emotional problems
• Psychological issues
While some symptoms can be more severe in the near term, even those patients who overcome the most significant impairments face longer-term deficits and difficulties. Among the most noteworthy persistent health problems reported by survivors between 1 and 5 years post-stroke are:
• Mobility limitations (58% of patients)
• Fatigue (52%)
• Difficulty concentrating (45%)
• Falls (44%)
Post-stroke cardiorespiratory fitness (as defined by measuring a patient’s VO2 peak) is approximately 50% of that in healthy people of the same age and sex. Muscle strength and muscle power show substantial and variable impairment. Consequently, the impact on the quality of life for stroke survivors is profound. Simple daily tasks are made more difficult, and complex mental and physical tasks often become an overwhelming, and sometimes impossible, challenge.
In other words, even for those fortunate to survive a stroke and overcome some of the most dramatic health impacts, life is often never the same.
Therapeutic Best Practices
Fortunately, post-stroke treatment is becoming more sophisticated, and therapeutic and rehabilitative professionals can draw from an increasingly deep well of studies and scientific analyses to determine what therapies are most effective in helping survivors recover as much function as possible in the wake of a CVA.
The following companies offer technologies that can be used for the rehabilitation of gait and balance disorders:
Allard USA Inc
Bionik Laboratories Corp
Clarke Health Care Products
GAITRite/CIR Systems Inc
Gorbel Inc-Medical Division/SafeGait
Physical Conditioning and Improved Functionality
It is an unfortunate irony that physical inactivity and poor cardiorespiratory fitness are not just risk factors for a stroke, they are also among the most common symptoms of stroke survivors. Consequently, it is certainly significant (if perhaps unsurprising) that increased physical activity and regular exercise may also have a role in reducing the chance of recurrent stroke and other comorbid conditions.
Upper limb motor impairments are particularly common and persistent in stroke survivors. The prevalence of bilateral limb weakness suggests that physical inactivity is at play. Studies show that:
• Resistance training to improve limb strength leads to increases in grip strength and upper limb function, but not necessarily to improved performance of the activities of daily living.
• Constrain-induced movement therapy improves disability and arm motor function at the end of intervention. The underlying effect here is likely to arise from an increase in physical activity of the habitually inactive affected arm.
• Repetitive task practice of functional movements does not benefit upper limb function, and simultaneous bilateral arm training does not improve performance of the activities of daily living—or functional movement of the arm(s) or hand(s).
Despite gaps in knowledge, there is a rationale for upper limb exercise after stroke. All approaches are designed to promote an increase in physical activity of the upper limbs.
Dealing with Fatigue
Fatigue is a damaging and sometimes underappreciated post-stroke symptom. Fatigue is quite commonly reported in stroke survivors, with a prevalence ranging from 38% to 77%.
The cause of fatigue is uncertain, but likely includes a combination of both psychological and physiological mechanisms. Reduced post-stroke physical fitness means that the effort required to perform different physical activities is greater and therefore more fatiguing. This may cause stroke survivors to avoid or reduce physical activity, contributing to a vicious cycle of additional deconditioning and increased susceptibility to fatigue. Studies have shown that therapeutic exercise programs address both root causes of fatigue, boosting both mental and physical fitness in a way that facilitates a more active, engaged, and energetic lifestyle for stroke survivors. The literature clearly demonstrates that cardiorespiratory training has a significant overall positive effect on pooled outcomes, including scales such as the Functional Independence Measure.
Addressing Balance, Gait, and Mobility Issues
In addition to the endurance, fatigue reduction, and overall fitness benefits provided by a therapeutic regimen of cardiovascular training, stroke survivors also showed significant improvements in balance. Cardiovascular training involving walking improved maximum walking speed and indices of balance. Preferred gait speed was improved by cardiorespiratory training (alone or in conjunction with strength training). Similar improvements were noted in gait endurance capacity. Therapeutic and rehabilitative programs that include cardiorespiratory training using walking, both with and without resistance, have also been shown to improve the speed and tolerance of walking at the end of intervention.
Therapeutic Technologies for Gait and Balance
A variety of equipment designed for the associated tasks of restoring the ability to walk is available to the inpatient and outpatient setting. These devices are available at a variety of price points, ranging from those that require very little clinic space to others that demand construction and build-outs. Among these technologies are systems designed to capture and analyze objective measures of gait, such as the GAITRite from CIR Systems, Franklin, NJ, which uses a pressure-sensitive electronic walkway to measure temporal and spatial parameters to help identify gait anomalies. Another device, the Zeno Walkway from ProtoKinetics, Havertown, Pa, has a pressure sensor in the base layer and detects pressure data during gait, balance, and other protocols.
The BodiTrak Sensor System from Vista Medical, Winnipeg, Manitoba, Canada, is another technology therapists can use to help assess gait. BodiTrak incorporates a Foot Smart Fabric pressure mapping system that can be used on a variety of surfaces that includes treadmills. Also useful for gait and balance evaluation is the platform-based Strideway from Tekscan Inc, South Boston, Mass, built to provide comprehensive gait analysis and generate objective, quantifiable data from heel contact to toe-off during the full gait cycle.
For clinics that work with larger floor space and budgets, an appropriate technology for gait recovery may include robotic devices or body weight support systems. For example, the SafeGait 360° Balance and Mobility Trainer from Gorbel Inc-Medical Division, Victor, NY, is an overhead track system that uses a trolley and harness, and is built to provide dynamic body-weight support and fall protection for early rehab post-stroke.
LiteGait from Mobility Research, Tempe, Ariz, is a gait training device that controls weight bearing, posture, and balance over a treadmill or over ground. It allows individuals to comfortably walk in a secure environment free of falls, altering weight-bearing capacity via a sling support. LiteGait provides proper posture, reduces weight-bearing, eliminates concerns for balance, and facilitates the training of coordinated lower extremity movement.
Another option is the Lokomat, a robotic device from Hocoma USA, Norwell, Mass, designed to provide highly repetitive physiological gait training that can be useful to therapists treating patients affected by neurological impairment. The user is supported by a harness suspended overhead while using an individually adjustable exoskeleton. Speed, loading, and robotic support all can be adjusted.
Patient confidence is reduced—sometimes significantly so—in the wake of a stroke. That lack of confidence, which both originates in and/or is exacerbated by the mental and physical deficits faced by the majority of stroke survivors, can contribute to a more sedentary and isolated existence. Qualitative studies examining community-based group exercise schemes suggest that stroke survivors gain social and physical confidence as a result of participation—benefits that extend beyond the direct psychological and physiological improvements resulting from therapeutic exercise.
Alleviating Cognitive Impairment
Cognitive impairment is common after a stroke. Almost two-thirds of stroke survivors report some degree of decreased cognitive function, a condition that is associated with both arterial stiffness and poor physical fitness. Exercise intervention has been shown to improve cognitive function in adults over the age of 65. The studies performed have examined the measurable benefits associated with specific exercises such as treadmill walking and stationary cycling.
Treating Aphasia and Visual Problems
Direct evidence in medical literature connecting exercise interventions to improvement in aphasia—diminishment in the ability to understand or express speech—or visual problems resulting from stroke is currently lacking.
There is, however, both an anecdotal and logical reason to believe that a therapeutic exercise program could elicit neurological improvements in stroke survivors. In humans, aerobic exercise stimulates the secretion of brain-derived neurotropic factors—a family of biomolecules which facilitate neuroplasticity by promoting neuron growth, health, and differentiation—which may play a role in facilitating motor adaptations to rehabilitation. PTP
Polly Swingle, PT, GCS, CEEAA, is co-founder and lead physical therapist of The Recovery Project, which provides progressive, effective, evidence-based neuro rehab therapies that improve the quality of life and functionality of patients with spinal cord, neurological, and traumatic brain injuries at its three Michigan-based locations. For more information, contact PTPEditor@medqor.com.
Gait Analysis: The Hidden Figures
By Frank Long, Editorial Director
Footsteps can speak volumes, but important temporo-spatial measures of gait may remain hidden to even a trained observer. Tools that collect and measure this data can help treat individuals who are trying to recover the ability to walk after a stroke, and provide objective measures to help them track progress. The following four technologies are important options therapists may want to know about when they need to gain a more complete picture of gait impairment.
CIR Systems, Franklin, NJ, offers systems that can be used for collecting data in a small lab or clinic, or a larger research facility. Combined with a sensor-equipped walkway, GAITRite’s proprietary software is designed to generate valid, reliable, objective temporo-spatial measures of gait in real time. An individual ambulates across the walkway, and the software records data capturing the geometry and relative arrangement of each footfall as a function of time and space. GAITRite systems are manufactured in a variety of lengths, made to be usable on any smooth surface, and reportedly can be set up in 75 seconds. A solar-powered model for outdoor use is also available.
The Strideway by Tekscan Inc, South Boston, Mass, uses a platform-based walkway that provides spatial-temporal data from multiple sequential footsteps during the gait cycle. Some of the key data the system provides for a broad range of tests includes information to pinpoint issues in the gait cycle, identify and correct pathomechanical dysfunctions, and measure change after treatment. Information for force and pressure time integrals can be generated in addition to plantar pressure profiles of pressure distribution. Strideway Systems are available in multiple sensor resolutions and lengths that range from 1 meter to 5 meters.
ProtoKinetics, Havertown, Pa, offers the Zeno Walkway, which has a wide surface that allows for the capture of assistive device performance in addition to the loading patterns of the patient’s footsteps. Additionally, PKMAS software is engineered to automatically eliminate walker tracks while expertly identifying overlapping steps, to provide robust temporal-spatial measurements. Applications for the Zeno Walkway include client evaluation, patient progress measurements, clinical research gathering, and education.
BodiTrak Balance System from Vista Medical Ltd, Winnipeg, MB, Canada, is designed to assess, train, and document an individual’s balance. The system features a sensing mat designed to be rugged, portable, flexible, and able to be used with a treadmill. BodiTrak uses advanced elastic sensors with built-in smart USB electronics. Users can simply plug the USB cable into a computer or connect to Smart Systems using WiFi and web browser interfaces. Sensor size and resolution is adjustable to specific applications.