Potential For Recovery In Central Nervous System Injuries
Pathology Perspectives
By Ruth Werner
Originally published in Massage & Bodywork magazine, September/October 2008. Copyright 2008. Associated Bodywork and Massage Professionals. All rights reserved.
According to statistical averages, a stroke, traumatic brain injury, or spinal cord injury will radically change the lives of 116 Americans this hour. Injuries to the central nervous system (CNS) can be devastating to the injured person and his or her loved ones and caregivers. The brain and spinal cord, so carefully protected by the three layers of meninges and the bony shells of the cranium and spinal canal, are extraordinarily vulnerable to damage if those protective layers are breeched by a blood clot, a gunshot wound, a motor vehicle accident, or other trauma.
This article will address the consequences of the most common kinds of CNS injuries, along with some new paradigms that are shaping the future of treatment strategies and the long-term prognoses for these events. Because some of these shifts involve muscle reflexes and proprioceptors, this puts the recovery process at least partly within the scope of practice for massage therapists, so we will also look at how bodyworkers can apply their skills in this context.
Traumatic Brain Injury
Traumatic brain injury (TBI) is an insult to the brain that is not brought about by congenital or degenerative conditions. This damage can lead to altered states of consciousness, cognitive impairment, and disruption of physical, emotional, and motor function. TBI is usually due to external force. Falls, gunshot wounds, motor vehicle accidents, physical violence, and sports are leading causes. About 1.5 million TBIs are reported every year, and 270,000 are classified as moderate to severe injuries, the rest are considered to be mild (although even mild injuries carry some significant risks).1
Most TBI patients are people between 15 and 25, or over 75 years old. Younger patients are injured in motor vehicle accidents, sports injuries, and personal violence, older patients are injured most often in falls.
Spinal Cord Injury
Spinal cord injury (SCI) is defined by damage to nerve tissue in the spinal canal. How that damage is reflected in the body depends on where and how much of the tissue has been affected.
Traumatic spinal cord injuries fall into one of five categories:
Concussions, in which tissue is jarred and irritated but not structurally damaged.
Contusions, in which bleeding in the spinal cord damages tissue.
Compression, in which a damaged disc, a bone spur, or a tumor puts mechanical pressure on the cord.
Laceration, in which the spinal cord is partially cut, as with a gunshot wound.
Transection, in which the spinal cord is completely severed.
Motor vehicle accidents cause about 50 percent of all spinal cord injuries. Falls are responsible for 24 percent, gunshot wounds and other acts of violence cause 11 percent, and sports-related injuries account for 9 percent. About 11,000 Americans experience an SCI each year, and about 250,000 people in the United States are SCI survivors. Male patients outnumber females by more than 4 to 1.
Statistics on other forms of spinal cord injury are not kept, but some estimates suggest that more people have been disabled by non-traumatic damage to the spinal cord (from arthritis, bone spurs, tumors, or other causes) than from accidents and injuries.
Stroke
Stroke or cerebrovascular accident (CVA) is the result of neuron damage related to ischemia or lack of blood supply. This can happen in one of two ways: 1) an ischemic stroke: a blood vessel becomes blocked with plaque, a clot, or other debris that develops on-site or travels from elsewhere, 2) a hemorrhagic stroke: a blood vessel ruptures and bleeds.
Stroke is the most common type of central nervous system disorder, the third leading cause of death in the United States, and the leading cause of adult disability. About 700,000 people have a stroke each year in this country. Of them, 500,000 are first attacks, and 200,000 are repeat strokes. About 160,000 people die of stroke annually. Close to 5 million stroke survivors are alive in this country today.
No matter what type of CNS injury occurs, internal edema, bleeding, and tissue damage may take several weeks to resolve. Most recovery of function appears to happen during this time. This is also when any residual motor impairment becomes apparent: damage to lower motor neurons reflects as flaccid paralysis, while damage to upper motor neurons shows as spastic paralysis--that is, flexors and extensors become progressively tighter, and ultimately the flexors win and the extensors let go.
According to statistical averages, a stroke, traumatic brain injury, or spinal cord injury will radically change the lives of 116 Americans this hour. Injuries to the central nervous system (CNS) can be devastating to the injured person and his or her loved ones and caregivers. The brain and spinal cord, so carefully protected by the three layers of meninges and the bony shells of the cranium and spinal canal, are extraordinarily vulnerable to damage if those protective layers are breeched by a blood clot, a gunshot wound, a motor vehicle accident, or other trauma.
This article will address the consequences of the most common kinds of CNS injuries, along with some new paradigms that are shaping the future of treatment strategies and the long-term prognoses for these events. Because some of these shifts involve muscle reflexes and proprioceptors, this puts the recovery process at least partly within the scope of practice for massage therapists, so we will also look at how bodyworkers can apply their skills in this context.
Traumatic Brain Injury
Traumatic brain injury (TBI) is an insult to the brain that is not brought about by congenital or degenerative conditions. This damage can lead to altered states of consciousness, cognitive impairment, and disruption of physical, emotional, and motor function. TBI is usually due to external force. Falls, gunshot wounds, motor vehicle accidents, physical violence, and sports are leading causes. About 1.5 million TBIs are reported every year, and 270,000 are classified as moderate to severe injuries, the rest are considered to be mild (although even mild injuries carry some significant risks).1
Most TBI patients are people between 15 and 25, or over 75 years old. Younger patients are injured in motor vehicle accidents, sports injuries, and personal violence, older patients are injured most often in falls.
Spinal Cord Injury
Spinal cord injury (SCI) is defined by damage to nerve tissue in the spinal canal. How that damage is reflected in the body depends on where and how much of the tissue has been affected.
Traumatic spinal cord injuries fall into one of five categories:
Concussions, in which tissue is jarred and irritated but not structurally damaged.
Contusions, in which bleeding in the spinal cord damages tissue.
Compression, in which a damaged disc, a bone spur, or a tumor puts mechanical pressure on the cord.
Laceration, in which the spinal cord is partially cut, as with a gunshot wound.
Transection, in which the spinal cord is completely severed.
Motor vehicle accidents cause about 50 percent of all spinal cord injuries. Falls are responsible for 24 percent, gunshot wounds and other acts of violence cause 11 percent, and sports-related injuries account for 9 percent. About 11,000 Americans experience an SCI each year, and about 250,000 people in the United States are SCI survivors. Male patients outnumber females by more than 4 to 1.
Statistics on other forms of spinal cord injury are not kept, but some estimates suggest that more people have been disabled by non-traumatic damage to the spinal cord (from arthritis, bone spurs, tumors, or other causes) than from accidents and injuries.
Stroke
Stroke or cerebrovascular accident (CVA) is the result of neuron damage related to ischemia or lack of blood supply. This can happen in one of two ways: 1) an ischemic stroke: a blood vessel becomes blocked with plaque, a clot, or other debris that develops on-site or travels from elsewhere, 2) a hemorrhagic stroke: a blood vessel ruptures and bleeds.
Stroke is the most common type of central nervous system disorder, the third leading cause of death in the United States, and the leading cause of adult disability. About 700,000 people have a stroke each year in this country. Of them, 500,000 are first attacks, and 200,000 are repeat strokes. About 160,000 people die of stroke annually. Close to 5 million stroke survivors are alive in this country today.
No matter what type of CNS injury occurs, internal edema, bleeding, and tissue damage may take several weeks to resolve. Most recovery of function appears to happen during this time. This is also when any residual motor impairment becomes apparent: damage to lower motor neurons reflects as flaccid paralysis, while damage to upper motor neurons shows as spastic paralysis--that is, flexors and extensors become progressively tighter, and ultimately the flexors win and the extensors let go.
The Traditional CNS Injury Paradigm
Understanding of the structure and function of the CNS has always suggested that the environment inside the brain and spinal cord is not conducive to healing and replacement of damaged cells, and that any damage or injury here is permanent and irreversible: the best anyone could hope for would be to prevent the damage from getting worse. Generations of observation show that in individuals with a CNS injury, the affected area of the body becomes progressively weaker and more disabled.
This observation led to a treatment strategy for CNS injuries that focuses on adaptation: teaching the person how to accomplish daily tasks with his or her strongest limbs, providing assistive devices to compensate for loss of strength and function, and changing the living environment as much as possible to keep challenges within a realistic spectrum for the patient's new limitations.
This approach allows many people to live independently after CNS injuries, but it has created an unexpected phenomenon: "learned non-use." In other words, the injured person, who has lost some nerve supply to his or her legs, or to one side of the body, essentially gives up on that area ever being able to function again. The proprioceptors relay information that their limitation is great and getting greater. The weakened limb(s) degenerate continually, taking the form of deconditioning, loss of muscle mass, and irreversible contractures. While some function loss is plainly inevitable, it seems clear that some is a self-fulfilling prophecy: the body senses a limitation and accepts that limitation as a done deal, thus, the limitation increases and progresses.
A New CNS Injury Paradigm
Beginning in the 1930s, neurobiologists and neurochemists made some unexpected discoveries about the CNS: damaged neurons in the brain and spinal cord are far more adaptable to external influences than previously thought. This recuperative capacity has been termed neuroplasticity.
It turns out that even a mature brain can grow new neurons or establish new connections between neurons where none had been seen previously. This raises exciting questions about how this capacity might be maximized or promoted in the context of tissue damage. Two main theories have developed around these findings: one is that intact cells may sprout collateral axonal endings (think of a plant growing new roots) to reach out to other neurons, the other is that previously unused or latent pathways between uninjured neurons could be recruited to provide function to damaged areas.
Another astonishing discovery found that the stepping reflex could be elicited in mammals with transected spinal cords. Proprioceptive sensations about weight-bearing, degree of flexion, or extension at hips, knees, and ankles, and rate of movement appear to stimulate a motor response to the degree that an injured animal--or human--could walk on a treadmill, as long as the circumstances are conducive.
New Treatment Strategies, New Prognoses
These and other surprising findings about CNS resilience have altered the strategies behind CNS injury treatments and substantially brightened the long-term outlook for survivors of these major events.
Traditionally, a survivor of a CNS injury has waited out the period when the nervous system resolves inflammation (approximately three months) to see what kind of function is left in order to make appropriate accommodations. These strategies do not incorporate the nervous system's adaptability, and an argument could be made that these interventions "enable disability" by discounting the potential for motor improvement.
Newer treatment plans focus more on recovery than adaptation. They take advantage of the self-regulating mechanisms that promote initial healing during the acute phase of injury by minimizing edema and oxidative stress (neuron damage related to free radical activity that occurs with injury). The chemical environment inside an injured CNS has profound influence on neuroplasticity. Some chemicals, especially gamma-aminobutyric acid (GABA), that are released during trauma actually damage neurons when present in high levels. Others appear to promote healing and create an environment where those intact axons can grow new endings or previously disused neural pathways can be recruited to provide function. Reducing the availability of harmful chemicals while increasing helpful ones during this phase has important influence on recovery potential.
Locomotor Training
When the acute phase subsides, new strategies address CNS injury by asking this key question: how much loss is real, and how much is related to "learned non-use"? For spinal cord injuries, this can be tested by utilizing the stepping reflex with a weight-bearing harness and treadmill. Aides can help create proprioceptive stimulus by exaggerating hip, knee, and ankle movements, but ultimately the injured person may be able to move on his or her own, even free of the treadmill. This is process is called locomotor training, and it holds great promise for SCI patients.
Constraint-Induced Movement Therapy
Stroke and TBI patients can translate neuroplasticity into improved function in a different way: the patient's strong side is immobilized so that everything the patient does must be done with the weakened limb. This intense work, called constraint-induced movement therapy (CIMT) can yield stunning results: long-term function is consistently better than for patients who undergo traditional therapy that focuses on strategies to use the strong limb side of the body. These improvements can be seen even if CIMT is applied years after the stroke or TBI.
What Does This Mean For Massage?
If at least part of a CNS injury patient's problem is related to proprioceptive information and learned non-use, then we can work with the rehabilitation team to promote a more accurate feedback loop about muscle strength and power. We can create bodywork sessions that soothe, calm, and promote improved function through proprioceptive facilitation.
Injuries that affect upper limb function may decrease a patient's ability to grasp or pinch. What if this patient's massage therapist did work to improve hand function? This could mean the difference between being able to drive or not, being able to use a computer or not, even being able to live independently or not.
Injuries that affect lower limb function obviously compromise the ability to walk. That ability can be restored in specialized circumstances, the boundaries of which are only now being explored and challenged. Again, if more accurate proprioceptive messages about muscle tone and the stretch reflex in leg muscles can be conveyed through bodywork, this could have influence on a patient's long-term prognosis.
CNS injuries carry a long list of cautions for massage practitioners. Numbness interferes with important sensory information about the risk of injury. Stroke patients may have other cardiovascular conditions, or a risk of another stroke. Spastic muscle fibers are vulnerable to injury. The threat of blood clots and deep vein thrombosis remains high for people who are not mobile. Urinary tract and kidney infections are a hazard for anyone using a urinary catheter, lung infections are a constant threat for people who can't cough well. Hyperreflexia is a situation where a minor stimulus creates a dangerously exaggerated sympathetic response. These risks can be mitigated with education, curiosity, adaptability of bodywork sessions, and good communication with the rest of the patient's care providers.
The impact that massage therapy may have on CNS injury and prognosis is an open question. New revelations about how adaptable an injured CNS truly is create a wide array of possibilities in which massage therapists may participate.
Ruth Werner is a writer and educator who teaches several courses at the Myotherapy College of Utah and is approved by the NCTMB as a provider of continuing education. She wrote A Massage Therapist's Guide to Pathology (Lippincott Williams & Wilkins, 2009), now in its fourth edition, which is used in massage schools worldwide. Werner is available at www.ruthwerner.com or wernerworkshops@ruthwerner.com.
NOTE
1. These numbers do not include military personnel injured in the wars in Iraq and Afghanistan. This population adds an estimated 320,000 to the total number of TBI survivors over the past five years.
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