Abstract:
This chapter provides a comprehensive discussion of interventions used by therapists to improve activity and participation of patient’s and patient’s with movement limitations. This chapter presents current evidence, clinical implications, and considerations for utility of these interventions in neurorehabilitation.
Keywords:
evidence-based practice, functional training, intervention for impairments, augmented intervention
Objectives
After reading this chapter the student or therapist will be able to:
- 1.
Appreciate the complexity of motor responses and discuss methods used to influence body.
- 2.
Analyze the similarities and differences among interventions that address impairments in specific body systems, and functional training.
- 3.
Identify the role of augmented feedback in neurological interventions.
- 4.
Select appropriate intervention strategies to optimize desired outcomes.
- 5.
Analyze variables that may both positively and negatively affect complex motor responses and a patient’s ability to perform functional activities and participate in the community.
- 6.
Discuss interventions in neurorehabilitation with regards to current evidence, clinical implications, and considerations for utility.
- 7.
Consider the contribution of the patient/client, available support systems, research evidence, neurophysiology, and the best practice standards available to optimize outcomes.
Before discussing therapeutic interventions, the therapist must identify the learning environment within which the patient/client will perform tasks/activities. That environment is made up of the therapist and the patient/client, all internal body control mechanisms of the patient/client, and the external restraints and demands of the environment. Although this text focuses on relearning functional movement, the reader must always consider many factors that influence the patient/client management, including how other organs or body systems will be affected by or will affect the therapeutic outcome, both during and after rehabilitation, in relation to long-term quality of life. An examination and evaluation are performed before intervention to establish movement diagnoses. A physical therapy diagnosis must link impairments at the body structure and function level to activity limitations and participation restrictions, as well as provide a prognosis of the patient’s/client’s potential for functional improvement. Personal factors, such as motivation, family support, financial support, patient values, and cultural biases, must be considered as part of the prognosis. Therefore the physical therapy diagnosis and prognosis guide the selection of intervention strategies. This text addresses interventions for patients/clients with movement system dysfunction associated with nervous system impairments. Prognostic accuracy and appropriate goal setting require clinical reasoning to distinguish if a specific activity limitation is due to an acute event or if the limitation has developed over a lifetime as a result of small traumas and adjustments to life.
Both the American Occupational Therapy Association (AOTA) and the American Physical Therapy Association (APTA) have developed standards of professional practice to guide therapists in the patient/client management process. , “The body of online tools to support evidence-based practice is growing, including diagnosis-specific interventions. Some tools are open access such as the Physiotherapy Evidence Database (PEDro) while others require professional membership.” , Through the use of current evidence-based practice of sensorimotor processing, motor control, motor learning, and neuroplasticity theories and body systems models, the therapist must determine the inherent motor control and learning flexibility the patient demonstrates while executing functional activities and participating in life. This chapter and text cannot establish for the reader the exact treatment sequence that should be used for every patient but presents an example of a decision making pathway in Box 8.1 . Functional goals must be established that lead to the patient’s/client’s ability to participate within his or her environment and whenever possible lead to or maintain the quality of life desired by the patient/client. Before beginning any intervention, the therapist must determine the treatment strategies that will be used to help the patient/client attain the desired functional outcomes. The specific environment used by the therapist to optimize patient performance will depend on the functional level and amount of motor control exhibited by the patient. In some cases the therapist may be constrained to use the existing environment and will need to modify it to meet the intent of the therapeutic session. The following classifications can be used to document the specific role of the therapist within the intervention session:
Functional training: Practice of a functional skill that is meaningful, goal directed, and task oriented. Patients will experience errors and self-correct as the program becomes more automatic and integrated. An example would be gait training on a tile surface, rugs, inclined surfaces, compliant surfaces such as grass, and so on, to practice ambulation.
Intervention for impairments: Treatment focus is on correcting an impairment in the body system with interventions such as muscle strengthening, stretching, sensory training, endurance training.
Compensation training
Use of an assistive device or orthotic to compensate for a permanent impairment or lost body system function.
Substitution training
Teaching the patient to use a different sensory system or muscle(s) group to substitute for lost function of another system. An example of sensory substitution might be teaching the patient to use vision to substitute for an impaired vestibular system or somatosensory system for balance function. Substitution within the motor system might be teaching hip hiking to substitute for lack of dorsiflexion of the ankle during swing phase of gait.
Habituation training
Activity-based provocation of symptoms with the goal of symptom reduction with repetitive practice. An example would be teaching head movement to a patient who has a chronic labyrinthitis and severe nausea with any head movement.
Neural adaptation
Driving changes in structure and function of the central or peripheral nervous system with repetitive, attended practice. This category would be considered neural plasticity. This category of treatment strategy takes the greatest repetition of practice and requires a strong desire by the individual to gain the functional ability and realize the potential of the central nervous system to change.
Whether the intervention approach is via functional training or intervention for impairments, the clinician may use augmented feedback strategies to optimize the patient’s response to the intervention strategy. The external feedback received by the patient (auditory, visual, kinesthetic, tactile, etc.) will limit the response patterns (e.g., reducing degrees of freedom, reduction or enhancement of tone) for successful performance of the desired movement. Examples of these are provided in the later portion of this chapter.
Patients/clients with central nervous system (CNS) damage often benefit from a combination of interventions from the above categories. An example of this might be the early phase of partial body weight supported treadmill training (BWSTT), where a therapist or assistant guides the patient’s/client’s leg during swing and stance phases while the body harness supports a proportion of the patient’s/client’s total weight (augmented feedback) to maintain balance and decrease the power needed to generate a more typical gait pattern. This augmented intervention is done in a functional pattern within an environment that perturbs the patient’s/client’s base of support. This perturbation moves each foot reciprocally backwards and the body forward, triggering a stepping reaction. In the case of an individual after a cerebrovascular accident (CVA), one leg will still respond normally, thus helping to trigger a between-limb reciprocal stepping action of the involved leg. In the case of bilateral involvement, both legs may need placement, requiring more external assistance. The intent of the intervention is to correct an impairment, leading to functional training to trigger normal motor programs necessary for gait. Simultaneously, augmented training done by a therapist includes manual assistance in the direction and rate of stepping, and placement of the involved leg throughout the gait cycle. In this previous example, therapists need to make sure they are aware of the patient’s center of gravity and do not move the foot before it should be at “push off” during the gait cycle. When selecting from a variety of treatment interventions, it is important for the therapist to consider that each intervention comes with different strategies and rationales that contribute to the expected outcome. All interventions should address the needs of the patient and must consider any emotional and cognitive restraints. Because these intervention strategies can be used simultaneously and in various combinations, it is important for the clinician to determine how and why the outcomes were influenced by the intervention. Without understanding the interactions of intervention methods and the outcome, treatment effectiveness and future clinical decision making remain unpredictable, and unique practice patterns and pathways are hard to identify with consistency. A conscientious clinician knows how and why the decisions are made along the intervention pathway, communicates this rationale clearly, and leaves a legacy of effective patient/client care. The reader must remember that intervention encompasses multiple interactive environments where intervention decisions are often made moment by moment during any treatment period. The challenge to the clinician is to determine what is being done, why it is working, how to continue its effectiveness, and how to assess/measure the progress of the successful intervention. The clinician must also determine how to empower the patient/client (emotionally, cognitively, and motorically) to participate in the intervention with inherent, automatic mechanisms that lead to fluid, flexible, and functional outcomes that are independent of the therapist and not purely exclusive to the environment within which the activity is occurring. The efficacy of a specific treatment is often yet unestablished in the laboratory and research literature; therefore the patient’s/clinician’s thoughtful choice of interventions and outcome measures is the first step in determining treatment effectiveness. Once efficacy has been established through larger controlled studies within the clinical environment, researchers can begin to tease out separate variables and establish efficacy as part of evidence to justify clinical decision making.
History of development of interventions for neurological disabilities
In the mid-1900s the interventions by physical therapists (PTs) and occupational therapists (OTs) were separate. In general, PTs worked on gross motor activities, with specific emphasis on the lower extremities and the trunk, whereas OTs worked on the upper extremities and fine motor activities. Both professions focused on daily living skills, with those involving the arms falling within the domain of the OT and those involving the legs falling within the domain of the PT. Activities that required gross motor skills such as sitting, coming to stand, walking, walking with assistive devices, and running fell within the purview of the PT, whereas grooming, hygiene, and eating were the responsibility of the OT. Currently, this approach is not as commonly practiced owing to the understanding of motor learning, neuroplasticity, and motor programming and control. In the past, it was also accepted that the PT worked on specific system problems such as weakness, inflexibility, lack of coordination, and voluntary control, whereas the OT worked on functional activities integrated within the environment (such as dressing) and the patient’s emotional needs and desires (occupational expectations). According to the terminology of the mid- to late 20th century, PTs were trained to identify and correct impairments that caused functional limitations, whereas OTs were trained in activity analysis and treatment that identified and optimized the functional activities that resulted from the impairments. Few clinicians seemed to focus on the sequential or interactive aspect of lack of function with specific impairments. Thus, after the onset of a stroke, the PT would strengthen and evaluate range of motion (ROM) of the leg and trunk, whereas the OT would encourage the patient to try to functionally use the arm. Both therapists hoped the patient would accept responsibility for continued improvement through practice. What both professions discovered was that the patient generally did not regain normal motor control. The patient may be able to walk and move the shoulder, but the movement strategies were generally stereotypical, were abnormal in patterns, and took tremendous effort by and energy from the patient to perform. Over time, patients lost the motivation to even try, and thus what had been gained through therapy may have been lost from lack of practice once they got home. There was also minimal recovery of functional hand use, often because of the tremendous effort a patient had to use to move the shoulder to place the hand somewhere. Once that effort had been used, the tightness and increased tone in the hand prevented functional use. Although measurable, functional, independent skills as were achieved, typical movement patterns and motor control were rarely restored, and quality of life was clearly affected for the patient and family.
During the decade or two before the 1960s, clinicians began to question the traditional therapeutic intervention strategies. Several renowned clinicians in neurological rehabilitation pioneered the development of new concepts that allowed basic science to infiltrate the clinical arena. The intervention strategies of Jean Ayers, Berta Bobath, Signe Brunnstrom, Margaret Johnstone, Susanne Klein-Vogelbach, Margaret Knott, Dorothy Voss, and Margaret Rood, among others, became popular. Colleagues observed these master clinicians and could easily see that the “new” interventions were much more effective and provided better outcomes than previous interventions. Each approach focused on multisensory inputs introduced to the patient in controlled and identified sequences. These sequences were based on the inherent nature of synergistic patterns , , , and motor patterns observed in humans , , and lower-order animals or a combination of the two. , Each method focused on the individual patient, the specific clinical problems, and the availability of alternative treatment approaches within an established framework. Some of these approaches focused on specific neurological medical diagnoses. The treatment emphasis was then on specific patients and their related movement disorders. Children with cerebral palsy and head injuries , , and adults with hemiplegia , , , were the three most frequently identified medical diagnoses associated with these approaches.
The timeline and evolution of clinical practice and research in the therapy professions can be derived in great part by understanding the products of a series of conferences, currently known as the STEP Conferences. A summary of the four STEP conferences follows in this section to give the reader contextual perspective of present day intervention strategies for prevention of primary and secondary impairments, the choice and application of predictive measures, strategies to enhance patient participation, and ongoing research to examine exercise-induced brain plasticity.
Beginning in 1968 at Northwestern University with NUSTEP, and most recently in 2016 at the University of Ohio for IV Step, master clinicians and academics along with research scientists of the day have come together to try to (1) identify the commonalities and differences between therapeutic approaches, (2) integrate and use the neuroscience of the day to explain why these approaches worked, and (3) promote the translation of new knowledge into clinical practice. Parallel to the STEP conferences, most dogmatism no longer persists with respect to territorial boundaries between PTs’ and OTs’ perceived ownership of a certain body systems or treatment approaches; this as result of the adoption of a systems model when looking at impairments, activity limitations, and participation in life interactions.
Since the 1970s, substantial clinical attention has also been paid to children with learning and language difficulties. , , Now these concepts and treatment procedures have been applied across the age spectrum for all types of medically diagnosed neurological problems seen in the clinical setting (refer to section Intervention Strategies of this text). This expansion of the use of any of the methods for any pathological condition manifested by insults from disease, injury, or degeneration of the brain seems to be a natural evolution given the structure and function of the CNS and commonalities in system problems and activity limitations that take the individual away from participating in life.
Since the II Step Conference in 1990, the boundaries for interventions began blurring. Intervention approaches such as proprioceptive neuromuscular facilitation (PNF) were then integrated into the care of patient’s with orthopedic problems and patients with neurological impairments. Currently, few universities within the United States teach separate sections or units on specific approaches but rather teach students to identify impairments, when and how these interfere with functional activities, and what body systems may contribute to activity limitations or participation restriction.
For example, assume that a patient/client with hemiplegia exhibited signs of a hypertonic upper-extremity pattern of shoulder adduction, internal rotation, elbow flexion, and forearm pronation with wrist and finger flexion. Brunnstrom would have identified that pattern as the stronger of her two upper-extremity synergies. Michels, although using an explanation similar to Brunnstrom’s to describe the pattern, would have elaborated and described additional upper-extremity synergy patterns. Bobath would have asserted that the patient/client was stuck in a mass-movement pattern resulting from abnormal postural reflex activity. Although the conceptualization of the problem certainly determined treatment protocols, the pattern all three clinicians would have worked toward was shoulder abduction, external rotation, elbow extension, forearm supination, and wrist and finger extension. The rationale for the use of this pattern within an intervention period would vary according to the philosophical approach. One clinician might describe the pattern as a reflex-inhibiting position (Bobath). Another would describe the pattern as the weakest component of the various synergies (Brunnstrom), whereas still another might identify the pattern as producing an extreme stretch and rotational element that inhibited the spastic pattern (Rood). How those master clinicians sequenced treatment from the original hypertonic pattern to the opposite pattern and then to the goal-directed functional pattern would vary. Some would facilitate push-pull patterns in the supine and side-lying positions and rolling. Others would look at propping patterns in sitting or at weight-bearing patterns of patients in the prone position, over a ball or bolster, or in partial kneeling. All have the potential of improving the functional pattern of the upper extremity and modifying the hypertonic pattern. One method may have been better than the others given a particular patient, but in truth, improved patient performance may have stemmed not from the method itself but rather from the preferential CNS biases of the patient and the variability of application skills among the clinicians themselves. That is, when a therapist intentionally uses specific augmented feedback to modulate the motor system’s response to an environment but does not identify the other external feedback present within that environment (e.g., lighting, sound, touch, environmental constraints), therapeutic results will vary. Because of variance, efficacy of intervention is often questionable, although the effectiveness of that therapist may be easily recognized.
Because of the overlap of intervention strategies and the infiltration of therapeutic management into all avenues of neurological dysfunction, various multisensory models were developed during the early 1980s. , These have continued to evolve into acceptable methods in the current clinical arena. Although these models attempted to integrate existing techniques, in reality they have created a new set of holistic treatment approaches. In July 2005, the III STEP conference was held in Utah to again bring current theories and evidence-based practice into the current clinical environment. The history of the three STEP conferences demonstrates the evolution of evidence-based practice from the first conference, where basic science was the only evidence to justify treatment, to the second conference, where evidence in motor learning and motor control began to bring efficacy to intervention. By the time the third conference was held, the research in neuro/movement science regarding true efficacy within practice and the reliability and validity of our examination tools set the stage for standards in practice. No proceedings from that third conference were published, but over the preceding years, articles covering most of the presentations had been published in Physical Therapy. The ultimate goal would be to develop one all-encompassing methodology that allows the clinician the freedom to use any method that is appropriate for the needs and individual learning styles of the patient as well as to tap the unique individual differences of the clinician. Although intervention currently is based on an integrated model, the influence of third-party payers, the need for efficacy of practice, and time constraints often factor into the therapist’s choice of intervention. Visionary and entrepreneurial practice ideas that have the potential to be effective will always be a challenge to future therapists. Those ideas generally originate within the clinical environment and not the research laboratory. For that reason, clinicians need to communicate ideas to the researcher, and then those researchers can develop research studies that test the established efficacy or refute that effectiveness. Few researchers are master clinicians, and few clinicians are master researchers; thus collaboration is needed as the professions move forward in establishing evidence-based practice.
Today’s therapists have replaced many of the existing philosophical approaches with patient-centered therapeutic interventions. Patient performance, values and preferences, available evidence, and the expertise of the clinician often play key roles in the clinical decision making process. Control of the combination of movement responses and modulation over specific central pattern generators or learned behavior programs will allow the patient opportunities to experience functional movement that is task oriented and environmentally specific. With goal-directed practice of the functional activity, neuroplastic changes, motor learning, and carryover can be achieved. With a better scientific basis for understanding the function of the human nervous system, how the motor system learns and is controlled, and how other body systems, both internal and external to the CNS, modulate response patterns, today’s clinicians have many additional options for selection of intervention strategies. Whether a patient would initially benefit best from neuromuscular retraining, functional retraining, or a more traditional augmented or contrived treatment environment is based on the specific needs identified during the examination and evaluation process.
No matter what treatment method is selected by a clinician, all intervention should focus on the active learning process of the patient. The patient should never be a passive participant nor should the patient be asked to perform an activity when the system problems only create distortion or demonstrate total lack of control of the desired movement. With all interventions requiring an active motor response, whether to change a body system impairment such as by increasing or reducing the rate of a motor response, modulate the tonal state of the central pattern generators and learned motor behaviors, or influence a functional response during an activity, the patient’s CNS is being asked to process and respond to the external world. That response needs to become procedural and controlled by the patient without any augmentation to be measured as functionally independent. In time, the ultimate goal is for the patient to self-regulate and orchestrate modulation over this adaptable and dynamic integrated sensorimotor system in all functional activities and in all external environments.
A problem-oriented approach to the treatment of any impairment or activity limitation implies that flexibility and neural adaptation are key elements in recovery. However, adaptation should not be random, disjointed, or non–goal oriented. It should be based on methods that provide the best combination of available treatment alternatives to meet the specific needs of the individual. Development of a clinical knowledge bank enables the therapist to match treatment alternatives with the patient’s impairments, activity limitations, objectives for improved function, and desired quality of life. A therapist no longer bases treatment on identified approaches, although specific aspects of those approaches may be treatment tools that will meet the patient’s needs and assist him or her in regaining functional control of movement. Intervention is based on an interaction among basic science, applied science, the therapist’s skills, and the patient’s desired outcomes. , In most cases, multiple intervention strategies must be included, but the therapist needs to be able to identify why those selected treatments will lead to system improvement, as well as documenting those findings using reliable standardized and acceptable clinical methods and terminology. These intervention strategies must be dynamic yet also understandable and repeatable. As new scientific theories are discovered, new information must be integrated to continue to modify treatment approaches.
Intervention strategies
Functional training
Functional training is a method of retraining the motor system using repetitive practice of functional tasks in an attempt to reestablish the patient’s/client’s ability to perform activities of daily living (ADLs) and participate in specific life activities. This method of training is a common and popular intervention strategy used by clinicians owing to the fact that it is a relatively simple and straightforward approach to improving deficits in function. A system problem such as weakness in the quadriceps muscle of the leg can be treated by muscle strengthening in a functional pattern that can be easily measured. Because of its inherent simplicity, functional training is sometimes misused or abused by clinicians. Most patients with neurological deficits have multiple subsystem problems within multiple areas, which forces the CNS to use alternative movement patterns to try to accomplish the functional task presented. If the therapist accesses a motor plan such as transfers but allows the patient to use programs that are inefficient, inappropriate, or stereotypical, then the activity itself is often beyond the patient’s ability. The patient may learn something, but it will not be the normal program for transfers. This activity often leads to additional problems for the patient.
The intricate relationship of body system problems, impairments, and functional limitations that decrease participation in the rehabilitation process are discussed. Functional training can be implemented once the clinician has identified the patient’s activity limitations. The clinician must first answer the questions: “What can the individual do?” “What limitations does the patient have when engaging in functional activities in his or her daily environments?” “Are there motor programs that are being used to substitute for typical motor function?” and “Can the therapist use functional training to improve body system problems within the context of the functional skill?” Once the therapist develops an understanding of the potential reasons for activity limitations and can alleviate the substitution and compensation for the deficit, functional tasks should be identified and practiced.
Effect of functional training on task performance and participation
The main focus of functional training is the correction of activity limitations that prevent an individual from participating in life. However, through repetitive practice of functional tasks and gross motor patterns, many of the patient’s impairments can also be affected. For example, if a therapist practices sit-to-stand transfers with a patient in a variety of environments and performs multiple repetitions of each type of transfer, not only can learning be reinforced, but the patient can also gain strength in the synergistic patterns of the lower extremities that work against gravity to concentrically lift the patient off of the support surface and eccentrically lower him or her down. Weight bearing through the feet in a variety of degrees of ankle dorsiflexion during transfer training will effectively place the ankles in functional positions. The act of standing also helps the trunk and neck extensors to engage in postural control. Varying the speed of the activity during the treatment can stimulate cerebellar adaptation to the movement task. Moving from one position to another with the head in a variety of positions stimulates the vestibular apparatus and may assist in habituating a hypersensitive vestibular system, allowing the patient to change body positions without symptoms of dizziness, resulting in a higher quality of life. Repetitive practice also affects the vasomotor system and may assist in habituating postural hypotensive responses.
Functional training should access the patient’s highest level of independent and uncompensated movement—this is often challenging. For example, early gait training for patient’s with acute stroke may take place in artificial environments, such as within parallel bars. If the therapist providing the training is not cognizant of the quality and goal of the patient’s postural control and body movement, the patient/may use a dysfunctional, inefficient motor program. An example outcome of prolonged, ineffective gait training within the parallel bars can be seen in a patient with CVA who relies heavily on the nonparetic upper extremity for support on one bar, resulting in the next compensation of forward trunk lean, then hip retraction and knee hyperextension on the hemiparetic limb during single limb stance phase. If this misuse of functional training is not recognized, the patient may have long-lasting dysfunctional use of both the upper and lower extremity.
Instead, the astute therapist will use strategies to help the patient to safely and gradually explore appropriate movement strategies, provide the patient with a variable practice environment for walking (e.g., out of the parallel bars), and ultimately improve the plasticity of the patient’s nervous system during recovery. Functional training is the best method of intervention when the patient has some motor abilities with limitations such as limited ROM or inadequate muscle power from disuse. Functional training will use existing abilities until fatigue sets in, which may be after only one or two repetitions. Increasing the repetitions and/or the power necessary to complete the tasks will lead to functional improvement. An intervention approach in the early 1990s that evolved as an offshoot of functional training was labeled clinical pathways. These pathways were established by health care institutions to improve consistency of management of patients who met specific medical diagnostic criteria. It has been proven that the implementation of these pathways reduces variability in clinical practice and improves patient outcomes. Health care practitioners also became aware that some individuals do not fall into these pathways and need to be treated according to the specific clinical problems that the patients were presenting.
Selection of functional training strategies
What is the “ideal” procedure for effectively and efficiently using functional training as a treatment intervention? First, it is suggested that the clinician identify and select procedures that will use the patient’s strengths to regain lost function and correct system limitations—”What can the individual do?” The clinician is also advised to avoid activities that may be too difficult and elicit compensatory strategies that may result in the development of abnormal, stereotypical movement and potentially create additional impairments. An example of this is using transfer training when the patient is unable to perform the task with some element of success. Once in a situation where the patient fails to perform the task, the patient uses approaches to prevent from falling, not activities that allow the patient to safely transfer. The therapist’s decision regarding what functional patterns or activities to practice, and in what order, will depend on several factors. The therapist must choose functional activities that are necessary for the patient to perform independently or manage with less help before being discharged home. For PTs, safe transfers and ambulation are generally the focus of functional training. For OTs, independent bathing, dressing, and feeding are major foci. Yet both PTs and OTs also need to be sensitive to the activities that the patient or the patient’s family want to improve to enhance the quality of life for everyone involved in the person’s case. The ability to get in and out of a car might be the most important activity due to frequent trips to the physician’s office and the primary caregiver’s limited abilities to physically assist.
It is suggested that the clinician modify or “shrink” the environment to allow normal motor programs to run. An example of this might be to limit the ROM an individual is allowed while performing a rolling pattern. The therapist may opt to start this movement with the patient in a side-lying position. The amount of patient movement may be even further limited by the therapist stabilizing the patient’s hips by using the therapist’s one leg in kneeling position against the patient’s posterior pelvis and the therapist’s other leg in half-kneeling position with the top leg of the patient over the therapist’s half-kneeling leg. In this way, the individual’s body can be totally controlled by the therapist; the patient can be encouraged to roll the upper part of his trunk both backward with the arm reaching back and then forward with the arm coming across the body toward a weight-bearing pattern on the hand. The therapist can change the rate of movement and also use his or her knees to control the range that the patient is allowed. The environment can be progressively “enlarged” to allow the patient/client to perform the activity in a functional context. Although this narrowing of the functional environment would be considered a contrived environment and must not be recorded as functional as defined in a functional or activities-based examination, it may allow the nervous system the opportunity to control and modify the motor programs within the limitations of its plasticity at the moment. This therapeutic technique could be used within a functional training environment or may fall into an augmented treatment approach category, given an individual who has neurological problems that prevent normal movement.
The goal of therapy is to move toward functional training as quickly as the patient’s motor system can control the movement. As learning and repetition assist the CNS in widening the response pattern during a functional activity, the patient’s ability to respond to variance within the environment will enlarge and assist in gaining greater independence. An example of this application of functional training might be asking a patient/client to perform a stand-to-sit transfer. The patient is first guided down to sitting onto a large gym ball, a high-low table, or a stool that allows the patient to sit only one-fourth to one-half of the way down before returning to stand. As the patient develops increased strength and balance and improved control over abnormal limb synergies and tone in this pattern, then a smaller gym ball or a lower point on a high-low table can be used. Finally, the patient is asked to sit down onto a ball/mat or chair that results in sitting with the hips and knees at 90 degrees. Once the patient can sit down and return to a vertical position, the next task will be to sit down, relax, and then stand up. When this task is done easily, the patient will be functionally able move from standing to sitting and to reverse the movement pattern to sitting to standing.
Although many clinicians understand the importance of running motor tasks within an appropriate biomechanical, musculoskeletal, and sensorimotor window in which the patient has the ability to perform procedures functionally, it may be argued that in many cases this particular type of treatment strategy is simply not possible in a real-world situation. For example, given the current health care environment, if the patient is given a limited number of visits to achieve the desired outcome, the clinician may conclude that there is no choice but to “allow as many degrees of freedom as possible” or, in other words, to “force the window open” no matter the abnormal movement patterns used or the limitations in independent functional control that they may produce.
In summary, the clinician should first identify and emphasize the patient’s strengths and use those strengths to efficiently and effectively achieve functional change. Next, the clinician must prioritize activities that need to be addressed; the choice of what activities to emphasize during therapeutic training always poses a dilemma to therapists. One should keep in mind that, although several skills may be learned by training them simultaneously, it may make more sense to concentrate on the safe performance of one or two necessary functional tasks rather than having the patient end up being able to perform multiple tasks that require considerable outside assistance for safety. The need to work functionally on additional activities may also be an opportunity for the clinician to request additional therapy visits for the patient/client, arguing that there is a reasonable expectation that more intervention would result in a greater increase in function and a greater decrease in the risk for potential injury than if the intervention were not continued. The use of valid and reliable functional outcome measures becomes critically important in case management. These tools objectively measure the effect of the intervention, help to predict the potential risks if the therapy is not continued, and ultimately aid in the justification to continue therapeutic intervention.
One important variable that has clearly been identified with respect to functional training is “task specificity.” , Although it is important that a patient be independent in as many ADLs as possible, often the therapist, the patient, and the family need to prioritize which activities are most important to the quality of life of the patient. If walking into the mountains to do “birdwatching” is one important goal to the patient, then creating an environment that would closely resemble the environment of that activity is crucial. Similarly, practice within that environment is a key to successful carryover. If the patient wants to walk into the mountains and the family expects the patient to walk into his or her old job, a therapist must accept that motivation will drive behavior and task specificity will drive learning. Carryover into any other functional activity such as walking into the office building to go back to work may not be the motivating factor that will guide that individual’s desire to perform that motor task. Whether the patient ever goes back to work is not the variable that should be used as part of the motivational environment for task-specific gait training geared to walking in the mountains and is not a decision for which the therapist is responsible. Therapists need to elicit the most important activities for the patient and use the specificity of that task to optimize motor learning and functional recovery.
Teaching a patient to ambulate can be approached in many ways. Assume that the objective for a particular session is ambulation. First, the patient may be asked to ambulate in the parallel bars using the upper extremities to assist in forward progression of the movement to decrease fear and to assist in maintaining balance. Once the patient can perform this ambulatory activity, the therapist might decide to progress the patient’s ambulation by introducing a walker, which has four points of support. Ambulating with the walker will again increase power production in the legs and create an environment of safety for the patient. Once walking with the walker can be performed at various speeds and distances, the therapist may advance the activity to using two canes, then one cane depending on the patient’s balance, coordination, and need. While the patient is practicing ambulating with cane(s), he may also be walking supported on a treadmill to increase endurance, velocity of gait, and power. Once the patient can ambulate safely with a cane, the therapist may decide to transition to walking without any assistive devices. Again, the patient may first be asked to walk on a treadmill while holding on with his arms until he feels safe walking and no longer needs an assistive device. The therapist could transition to ramps, obstacles, uneven ground, and so on. All these activities would require the individual to begin with functional control. All the activities are focused on regaining independence in the functional activity of walking, using repetitive practice. Training can continue with or without an assistive device, with consideration that a device itself will usually limit the environments within which a patient can ambulate independently.
Intervention for impairments
The therapeutic examination results in the identification of activity limitations and possible body system and subsystem impairments that are causing the functional movement disorders. Directly addressing these system impairments is another intervention strategy that involves the intervention for impairments with the expectation that improving these will result in a corresponding improvement in function. For example, when a patient has the inability to stand up without assistance (activity limitation) and the clinician determines the cause to be lower-extremity weakness, an appropriate approach may be to strengthen the lower extremities. Numerous studies have shown the effectiveness of addressing impairments directly in improving the functional performance of individuals with neurological conditions such as cerebral palsy, , stroke, multiple sclerosis, Parkinson disease, and other neuromuscular diagnoses. Considering the previous case, the strengthening interventions should reflect the task and the environment within which the impairment was identified. The clinician should attempt to create a training situation so that the patient may be able to run the necessary motor programs with all the required subsystems in place. For example, training sit-to-stand with weakness in the hip and knee extensors is much less likely to automatically result in the improvement of sit-to-stand function if the therapist begins the activity in sitting, where generation of extension is most difficult, than if the strengthening training was performed with repetition of practice starting in standing and going to sit and back again to stand. By decreasing the degrees of freedom of the eccentric control of the hips and knees when going from stand to sit, the functional training activity has turned into specific impairment training. The therapist can ask the patient to eccentrically lengthen the extensors only in a limited range and then concentrically contract back to standing. As the power increases, the degrees of freedom can also be enlarged until the patient is able to complete the task of stand to sit while simultaneously regaining the sit to stand pattern. In pure impairment training, a patient might also be asked to straighten the knee when sitting or to extend the hip when prone. These three exercises have the potential of training impaired strength, but only the first example forces the training within a functional pattern. Similarly, the therapist could train the sit-to-stand pattern using various seat heights that encompass many of the components that force the use of normal movement synergies and postural control, using the environment in which that activity is typically performed, versus performance of strengthening exercises against resistance in an open chain exercise program.
The decision to treat the impairments causing the activity limitations or to correct the functional problems themselves is influenced by many factors. One critical factor is the therapists’ ability to isolate the cause of the atypical movement pattern. Different impairments may potentially contribute to atypical movement; thorough movement analysis and testing should elicit the impairments that at contribute most to movement dysfunction and that should be targeted during interventions. It would appear that for certain tasks to be completed the patient must possess the “threshold amount” of basic movement components required for the task. Task specificity within this limited environment will result in more meaningful changes in function.
Augmented therapeutic intervention
Some treatment alternatives require little if any hands-on therapeutic manipulation of the patient during the activity. For example, the patient practices transfers on and off many support surfaces with standby guarding only. The patient self-corrects or uses inherent feedback mechanisms to self-correct error to refine the motor skill. This ultimate empowerment allows each individual to adapt and succeed at self-identified and self-motivated objectives first with augmented intervention and finally without any assistance. Often, allowing the patient to attempt movement without assistance enables the therapist to evaluate what components of the task the patient can control and what components are not within the patient’s current capabilities, especially if normal, fluid, efficient, and effortless movement is the desired outcome. In some cases, the therapist may use hands-on skills or augmented aids such as BWSTT, which would substitute for many aspects of the environment and allow the patient to succeed at the task— but the control and feedback during the activity would be considered augmented feedback and fall into that classification.
Augmented techniques make up a large component of the therapist’s specific interventions tool box. Augmented training may be done as part of a functional, task-specific activity but could also be administered in nonfunctional positions, depending on therapeutic goals. In augmented training the therapist may use a piece of equipment to be part of the patient’s external environment for the patient to succeed at the task. For example, in BWSTT a harness is used to take away the demand of gravity on the limbs during gait and the demand of the postural trunk and hip muscles for stability. Before the therapist or the patient can consider the movement as independent, those aspects must be removed from the environment. In the previous example, the individual needs to transition from maximal body weight support during ambulation to not needing any external support during ambulation. The patient must assume total ownership of the functional responses. Then and only then has independence been achieved. At that time, functional retraining can be used with the intent of enlarging the environmental parameters to allow for maximal independence. Augmented techniques are often the early choices for treatment of patients who have neurological insults. It cannot be emphasized enough that once the patient has the ability to perform without augmented methods and does so in functional, efficient ways, those augmented techniques need to be selectively eliminated.
Once a clinician has chosen to augment the clinical environment, the patient needs to learn efficient motor behaviors within the limitations of that environment. The patient influences the therapist’s decision making strategies by selecting inefficient or ineffective motor responses to a given task demand. If the response is effortless, efficient, and noninjurious to any part of the body and meets the patient’s expectations and goals, then the therapist knows the strategies selected were effective even if the therapist augmented the intervention. If the movement itself is available to the patient, then there is a high probability that the patient will be able to regain that movement control, regardless of the need for early augmentation to achieve the skill. If the response does not meet the desired goal for any reason, then the therapist must determine why. Often, it is because the therapist did not identify the correct body system impairments. Which solution is best may be more patient than approach dependent. Fig. 8.1 summarizes the use of these intervention approaches as a roadmap for neurological rehabilitation.
The clinician has little basis for decision making without a comprehensive understanding of the neurophysiological mechanisms of (1) the various techniques introduced to modify input, (2) where that information will be processed and how that might affect motor output, (3) prior learning and the ability for new learning, and (4) the patient’s willingness and motivation to adapt.
The number of available augmented feedback techniques is almost infinite. This section presents an overview of a classification system that can be used to help the reader develop a greater understanding of why certain responses occur and why the selection of certain techniques is appropriate and should positively affect the desired motor responses. This section focuses on intervention strategies that have been accepted, have been used within the traditional Western health care model, and are efficacious. There are other classification systems a clinician might use when analyzing movement problems seen in patients with neurological dysfunction. For example, a therapist may see in a patient a problem primarily with tone, such as hypertonicity, hypotonicity, rigidity, dystonia, flaccidity, intentional and nonintentional tremors, ataxia, and combinations of or fluctuations in the total movement strategies. Given this specific classification schema, one still uses the available treatment strategies or uses an input modality that may modify the specific tone problem that was causing the movement dysfunction.
The primary goal of this section is to help the reader develop a classification system based on the primary input modality used when introducing an augmented treatment technique to facilitate a sensory system and provide feedback to the CNS to help a patient learn or relearn motor control.
When the primary input system for a technique is identified, at no time do we suggest that it is the only input system affected. For example, when a proprioceptive technique is introduced, tactile cutaneous receptors are also simultaneously firing. If there is a “noise” component (such as with vibration or tapping with the fingers), then auditory input has been triggered as well. There is evidence that a given sensory modality may “cross over” or fuse with a completely different modality, helping in the synthesis of motor responses. In addition, there is evidence that the principles of neuroplasticity are applicable across modalities (e.g., auditory, visual, vestibular, somatosensory). Sometimes responses occur in a modality that does not appear to be related. For example, olfaction may improve tactile sensitivity of the hand. This concept is called cross-modal training or stimulation. , Yet, a classification schema based on a primary modality promotes logical problem solving because the therapist can select from available treatment procedures that theoretically provide similar information to the CNS and help in the organization of appropriate motor responses. The motor system and its various motor programmers adapt to the environment to achieve functional motor output toward a goal. Both external and internal feedback are critical for adaptation and change. External feedback in this chapter is considered a mechanism to help the patient’s CNS optimally learn and adapt. Obviously, as the patient learns, internal feedback will allow the person to run feedforward motor programs without the need for external feedback for control. External feedback will, it is hoped, be used only when the outside surrounding needs the feedforward program to change to adapt to a new environment (refer to the Chapter 3 section on motor learning). Therapists must realize that even if the primary goal may be to facilitate or dampen a motor system response, diverging pathways may also connect with endocrine, immune, and autonomic systems. According to motor control theory, the clinical picture is a consensus of all interacting body systems (see Chapter 3 ). Research tools are not yet available to measure those systems interacting simultaneously, although functional magnetic resonance imaging (fMRI) studies are beginning to help researchers and clinicians identify what happens to the nervous system with input from the environment and how that information is processed. Efficacy using reliable and valid measurement tools must then be based on outcomes, with an understanding of the best available scientific knowledge as a rationale for why the outcome is present.
This classification system is based on identified input, observed responses, current research on the function of the CNS, and the various systems involved in the control and modification of responses. An understanding of normal processing of input and its effect on the motor systems helps the clinician to evaluate and use the intact systems as part of treatment. Research with fMRI is currently allowing greater insight into specific brain regions that are being used during various cognitive and motor activities. Yet the specific interactive nature of multisensory input, memory, motivation, and motor function is still unknown. When the response to certain stimuli does not help the patient select or adapt a desired motor response, then the classification schema for augmented input provides the clinician with flexibility to select additional options. This can be done by spatially summating input, such as using stretch, vibration, and resistance simultaneously, or temporally summating input, such as increasing the rate of the quick stretch or increasing the time between inputs to give the system ample time to respond.
Many factors can influence motor behavior, such as the methods of instruction, the resting condition of the nervous system, synaptic connections, cerebellar or basal ganglia or cortical processing, retrieval from past learning, motor output systems, or internal influences and neuroendocrine balance. Its clinical implications become clearer if the therapist retains a visual image of the patient’s total nervous system, including afferent input, intersystem processing, efferent response, and the multiple interactions on one another. At any moment in time, multiple stimuli are admitted into a patient’s input system. Before that information reaches a level of primary processing, it will cross at least one if not many synaptic junctions. At that time the information may be inhibited, excited, changed or distorted, or allowed to continue without modification. If the information is at the first synapse, the patient will have no sensation. If it is inhibited at the thalamus, again the patient will not perceive sensation, but that does not mean other areas of the brain will not be sent that information, because sensory information is also sent to a variety of areas after that initial synapse. Research studies have found that sensory input information may even affect gait and other movement patterns even if the patient has no perception of the input. , If the input is changed, then the processing of the input will vary from the one normally anticipated. The end product after multiple system interactions will be close to, will be farther away from, or will seem to have no effect on the desired motor pattern. Furthermore, sensory processing can take place at many segments of the nervous system. Although the CNS is not hierarchical, with one level in total control over another, certain systems are biased to affect various motor responses. At the spinal level the response may be phasic and synergistic. Brain stem mechanisms may evoke flexor or extensor biases, depending on various motor systems and their modulation. Cerebellar, basal ganglia, thalamic, and cortical responses may be more adaptive and purposeful. Thus the therapist must try to discern where the input or the feedback is being affective or short circuited.
Remembering input as a possible option for intervention will always allow the therapist to differentiate the same five alternatives—no response, facilitating (heightening), inhibiting (dampening), distorting, or normal processing. These alternatives can occur anywhere in the system at synaptic junctions. Finally, motor output is programmed and a response is observed. If the response is considered normal, the clinician assumes that the system is intact with regard to the use and processing of the inputs. If the response is distorted or absent, little is known other than there is a lack of the normal processing somewhere in the CNS or an insufficient amount of input was used. One way to differentiate motor problems from problems with other systems is to use other functional activities that have programs similar to the body system program identified as impaired. If a program, such as posture, demonstrates deficiencies in one functional pattern, then the therapist must determine if it is also deficient in other patterns. If the postural motor problem affects all motor performance, then the therapist had determined that a motor program deficit exists and will have to determine how to correct that problem. If, on the other hand, the program runs smoothly and effortlessly when certain demands are taken away, such as resistance from gravity, position in space, need for quick responses, and so forth, then it may be that the problem is within another subsystem such as cognition, perception, the biomechanical system, or the cardiopulmonary system or is a power-production problem that can be corrected by slowly increasing the demand on the postural system through repetitive practice using various additional input interventions. Differentially screening motor impairments as pure CNS motor problems (muscle recruitment, firing rate, balance) versus problems with another system (perception of vertical) becomes critical in a managed-care system that funds only a certain number of treatment sessions. Once normal processing has been identified, understanding of deficit systems and potential problems can be analyzed more easily. To reiterate, this requires awareness of the totality of the individual (i.e., the patient’s personal preference of stimuli and the uniqueness of processing and internal influences). A systems model requires simultaneous processing of multiple areas, with interactions being relayed in all directions. A patient’s CNS and peripheral nervous system (PNS) are doing just that, and the therapist must develop a sensitivity toward the patient as a whole while interacting with specific components. With input from the patient and family, it is the therapist’s responsibility to select methods most efficacious and effective for each patient’s needs in relation to that person’s specific neurological problems. This viewpoint, based on a variety of questions, leads to a problem-oriented approach to intervention. Because the output or response pattern is based on α motor neuron discharge and thus extrafusal muscle contraction, the first question is posed: what can be done to alter the state of the alpha motor neuron pool or motor generators? Second , what input systems are available, either directly or indirectly, that will alter the state of the motor pool? Third , which techniques use these various input systems as their primary modes of entry into the CNS? Fourth , what internal mechanisms need modification or adaptation to produce a desired behavior response from the patient? Fifth , which input systems are available to alter the internal mechanism and what outcomes are expected? Sixth , what combination of input stimuli will provide the best internal homeostatic environment for the patient to learn and rehearse a more optimal response pattern? For example, assume that a patient with a residual hemiplegia resulting from an anterior cerebral artery problem has a hypertonic lower extremity that produces the pattern of extension, adduction, internal rotation of the hip, extension of the knee, and plantarflexion inversion of the foot. The answers to the first two questions are based on the knowledge that the proprioceptive and exteroceptive systems can drastically affect spinal central pattern generators and that these input systems are intact at spinal, brain stem, cerebellum, and thalamic levels and may even project to the cortex.
Appropriate selection of specific techniques will provide viable treatment alternatives. Awareness that a patient’s/client’s response pattern is an inherent synergistic pattern leads to a better understanding of the clinical problem. Knowing that the patient/client is unable to combine the alternative patterns, such as hip flexion with knee extension needed for the late stage of swing phase through the early aspects of stance phase during gait, the therapist can use the other inherent processes to elicit these and other patterns. BWSTT is an example of an augmented treatment intervention in which the clinician assists the patient to place the leg and foot with each step while the apparatus controls balance and posture to provide an experience of normal gait while requiring the patient to have only the strength to manage partial body weight. Finally, techniques such as combining standing and walking with the application of quick stretch, vibration, or rotation, or having the patient reach for a target or follow a visual stimulus while walking, provide a variety of combinations of therapeutic procedures to help the patient learn or relearn normal response patterns. Furthermore, combining techniques gives the clinician a choice of various procedures and promotes a learning environment that is flexible, changing, and interesting. The therapist must, again, make the transition from applying contrived therapeutic procedures during functional tasks to allowing the patient to practice the task without the therapist interceding and without external feedback. In that way the patient uses inherent feedback to self-correct feedforward motor programming and then to continue running the appropriate movement strategies.
Proprioceptive system integration of stretch, joint, and tendon receptors
Proprioceptive training is proposed to benefit somatosensory and sensorimotor function through cortical reorganization that occurs in response to repetitive active or passive movement. Proprioception as an input system has a direct effect on program generators at the spinal level. However, because of its importance in motor learning and motor adaptation to new or changing environments, proprioception also has significant connections to the cortical and cerebellar neural networks. Its divergent pathways have synapses within the brain stem, diencephalon, and spinal system. Proprioceptive input can potentially influence multiple levels of CNS function, and all those levels can potentially modulate the intensity or importance of that information through many different mechanisms. , Proprioceptors are found in three peripheral anatomical locations: the stretch receptors, the tendon, and the joint. The afferent receptors responsible for relaying sensory information through those sites are discussed in the following subsections.
Muscle stretch receptors
Stretch.
Stretch, quick stretch, and maintained stretch are all sensory input systems that use the stretch receptors in the muscles and heighten the motor pool. Stretch simultaneously heightens both the muscle response to that stretch and potentially heightens the sensitivity of the agonistic synergy. It will also lower the excitation of the antagonistic muscle and those muscles that are part of the antagonistic synergy. Stretch information will be sent to higher centers for sensory integration and perception. The cerebellum uses this incoming feedback to maintain and/or regulate motor nuclei in the brain stem that will influence the state of the α and γ motor neurons. This allows for cerebellar feedforward regulation (refer to Chapter 19 ). There are many ways to apply stretch to the muscles. The therapist can use (1) the hands and their respective muscle power to apply a stretch, (2) a manual weight system of some sort that maintains the stretch through the range, (3) a suspension system such as used in Pilates exercises, (4) the patient’s own body weight against gravity, (5) a complex robotic system that computerizes the amount of stretch depending on the individual’s specific data, or many other creative ways to apply stretch to muscle fibers within the belly of the muscle tissue. As stated previously, stretch can also be applied to the antagonist muscle or muscle synergy to dampen agonist function. Thus stretch can be used to enhance tone in the agonist or to decrease tone of the agonist through the antagonist. The therapist should always remember that even though a response may not look obvious, as long as the peripheral nerves and motor neurons within the spinal system are intact, these approaches will change the state of the motor pool.
Table 8.1 lists a variety of treatment procedures believed to use proprioceptive input from the muscles as a primary mode of sensory stimulation. The varying intensity, amount of tension, or rate of the stimuli, in addition to the original length of the muscle before application of the stimulus, will determine its firing. Remember, afferent information is projecting to many areas above the spinal system, and the result will be regulation or modulation, ultimately affecting activity.
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Resistance and strengthening.
Resistance is often used to facilitate intrafusal and extrafusal muscle contraction. Resistance can be applied manually, mechanically, and by the use of gravity. Resistance recruits more motor units in the target muscles. Although muscles can contract both in an isometric and an isotonic fashion, most contractions consist of a mixture of the two. Certain muscle groups, such as the flexors, benefit from isometric exercise, as well as isotonic exercise in both eccentric and concentric modes. Under normal circumstances, the flexors are used for repetitive or rhythmical activities. The extensors, on the other hand, usually remain contracted in an effort to act against the forces of gravity. Therefore the extensor groups benefit best from isometric and eccentric resistance.
When resistance is applied to a voluntary muscle, spindle afferent fibers and tendon organs fire in proportion to the magnitude of the resistance. Resistance is more facilitative to an isometrically contracted muscle than in an isotonic contraction. As isometric resistance is increased or continued, more motor units are recruited, thereby increasing the strength of extrafusal contraction. Eccentric isotonic contraction refers to the lengthening of muscle fibers with resistance added to the distal segment, as in lowering the arms while holding a heavy weight. Eccentric contraction uses less metabolic output and promotes strength gains in less time. Resistance is an important clinical treatment and has been used and will continue to be used by clinicians within multiple treatment philosophies over the next millennium. , , , , , The complexity of neural adaptation after resistive exercises may lead to a different training environment depending on age, athletic status, and specific body system deficits. Combining resistive training with guided imagery or other types of adjunct interactions has conflicting results. Yet there are still questions regarding optimal resistive training, in particular, the parameters of load and work frequency, , and whether one resistive technique is better than another. , Research certainly has shown that resistance training does enhance functional abilities across age groups, , , but again the specific resistive training techniques are often not identified. The terms resistive training, weight training, and strength training are often used synonymously, and thus specifics are yet to be identified in the research. How all these uses of resistive exercises will play out in the future is up to future researchers in the field of movement science. Very costly high-technology tools have been added to aid in resistive training. , Given the needs of individuals after neurological insults, cost becomes a major factor, and finding creative and cost-efficient ways to apply resistance may become a common research question in the future.
Tapping.
Three types of tapping techniques are commonly used by therapists. Tapping of the tendon is a fairly nondiscriminatory stimulus. Physicians use this technique to determine the degree of stretch sensitivity of a muscle. A normal response would be a brisk muscle contraction. Because of the magnitude of the stimulus and the direct effect on the α motor neuron, this technique is not highly effective in teaching a patient to control or grade muscle contraction. Instead, tapping of the muscle belly, a lower-intensity stimulus, is more satisfactory. Reverse tapping is a less frequently described technique, but it can be used. The extremity is positioned so gravity promotes the stretch, instead of the therapist manually tapping or actively inducing muscle stretch. Once the muscle responds, the therapist taps or passively moves the extremity to help the muscle obtain a shortened range. An example of reverse tapping would be tapping the triceps muscle when the patient is bearing weight on the extended elbow and actively trying to achieve full elbow extension. Timing of this technique is important. Gravity quickly stretches the triceps. If the timing follows the quick stretch to the extensor, then the flexors will be dampened and active extension more likely a motor response. If the therapist taps the elbow toward extension when the flexors’ motor neurons are sensitive, then those flexor muscles may respond to the stretch and contract, taking the arm farther into flexion.
Positioning (range).
The concept of submaximal and maximal range of muscles is highly significant to clinical application. Bessou and colleagues monitored the neuronal firing of muscle spindles at different ranges of motion. Upper motor neuron lesions can alter the sensitivity of the spindle afferent reflex arc fibers by not using presynaptic inhibition to normally dampen incoming afferent activity. Therefore ROM should be carefully assessed on an individual basis, particularly in a patient with an upper motor neuron lesion, to determine the maximal or submaximal range for an individual. Therapists always need to determine whether the difference between optimal range and functional ROM is different. If a patient will never need to use full ROM, then spending long periods of time trying to stretch a shoulder or hip to end-range of tissue mobility may not be the best decision with regard to intervention. Therapists also need to carefully evaluate excessive range resulting from hypermobility and hypotonicity. In those situations, external support of the affected joint or limb needs to be considered in all functional positions in order to prevent complications such as pain.
Stretch pressure.
The muscle belly is the stimulus focus of stretch pressure. The therapist slowly applies pressure to the muscle belly. It is used to decrease or release tone in the target muscle, allowing for the (temporary) recovery of voluntary movement. , Generally this type of stimulus is applied and maintained for a period of time (e.g., 5 to 10 seconds). It is not a quick stimulus and may be using the tendon organ to dampen tone. This type of pressure technique is also used in a variety of complementary approaches (see Chapter 39 ).
Stretch release.
This technique is performed by placing the fingertips over the belly of larger muscles and spreading the fingers in an effort to stretch the skin and the underlying muscle. The stretch is done firmly enough to temporarily deform the soft tissue so the cutaneous receptors and Ia afferent fibers may produce facilitation of the target muscle. It is easy to determine quickly whether the response is efficacious by just feeling and looking at the response of the patient.
Manual pressure.
Manual pressure can be facilitatory when it is applied as a brisk stretch or friction-like massage over muscle bellies. The speed and duration at which the manual pressure is applied determine the extent of recruitment from receptors. Paired with volitional efforts, manual pressure can lead to motor function and, with repetition, motor learning.
Vibration.
There are two types of vibratory methods used therapeutically. The first deals with the use of a handheld vibrator to facilitate Ia receptors to enhance agonistic muscle contraction in hypotonic muscles or to facilitate Ia receptors of antagonistic muscle fibers to inhibit hypertonic agonists. Currently the use of vibration to facilitate Ia responses within specific muscle function has been used to show how proprioception can be used to alter upright standing. , The second type of vibratory method is a total-body vibration to facilitate postural tone and balance and is applied through the feet in a standing position.
Bishop , wrote an excellent series of articles on the neurophysiology and therapeutic application of vibration in the 1970s. High-frequency vibration (100 to 300 Hz or cycles per second) applied to the muscle or tendon elicits a reflex response referred to as the tonic vibratory response. Tension within the muscle will increase slowly and progressively for 30 to 60 seconds and then plateau for the duration of the stimulus. Some researchers found that at cessation of the input the contractibility of the muscle was enhanced for approximately 3 minutes. , The discrepancy in the research may reflect the way the individual is using the input, both from a direct effect on the motor generator and from supraspinal modulation over the importance of the input, which may affect the overall learning and plasticity of the CNS. To facilitate hypotonic muscle, the muscle belly is first put on stretch, and then vibratory stimuli are applied. To inhibit a hypertonic muscle, the antagonistic muscle could be vibrated. , The use of vibration can be enhanced by combining it with additional modalities such as resistance, position, and visually directed movement. Vibration also stimulates cutaneous receptors, specifically the pacinian corpuscles, and thus can also be classified as an exteroceptive modality. Because of its ability to decrease hypersensitive tactile receptors through supraspinal regulation, local vibration is considered an inhibitory technique (it is also discussed later in the section on exteroceptor-maintained stimulus).
Amplitude or amount of displacement must also be considered when vibration is analyzed as a modality. It has been reported that high amplitude causes adverse effects, especially in patient’s with cerebellar dysfunction. Vibration is not recommended for infants because the nervous system is not yet fully myelinated and the vibration might cause too much stimulation. The reader is also cautioned about using vibration over areas that have been immobilized because of the underlying vascular tissue potential for clotting. Vibration on or near these blood vessels could dislodge a clot, causing an embolism. Vibration also needs to be used cautiously over skin that has lost its elasticity and is thin (e.g., that in older persons) because the friction itself from the vibration can cause tearing. The therapist must always keep in mind the environment and the functionality of an intervention procedure. The use of vibration may assist the patient in contractions and somatosensory awareness, but it is an unnatural way to facilitate either system and thus needs to be removed as part of an intervention as soon as the patient demonstrates some sensory awareness and/or volitional control over a movement component.
Within the past decade, the use of vibration of specific muscle groups of the neck has been studied to determine its effect on upright standing and the interaction with and without eyes open. , These studies showed that by vibrating specific muscle groups, those muscles would actively contract and change the position of the head in space but that with eyes open the effect was minimized in relation to global postural control. A similar study examined the effect of vibration on various muscles within the lower extremities and how that affected various postural responses. , These researchers found that different frequencies affected different muscle groups. The one consistent thing all studies have shown is that vibration does facilitate Ia muscle fibers, which in turn affect muscle contraction of the agonist receiving the vibration. Other sensory systems can assist or override the effect of vibration, but that is because of superspinal influence over motor generators.
Total-body vibration is currently being used to determine if it affects motor performance. Studies have shown that whole-body vibration can enhance motor performance in high-level athletes performing sprints and jumps, , as well as improve trunk stability, muscle tone, and postural control in individuals after stroke while in geriatric rehabilitation. Its application for individuals with neurological dysfunction is inconclusive. , Studies specifically directed toward the elderly again show promise, but further research is needed for specificity. Future research will need to determine the effect of total-body vibration when introduced to all populations of individuals with neurological dysfunction. At that time, both amplitude and magnitude will need to be identified to replicate studies. Total-body vibration certainly falls under primarily proprioception but also could be classified under combined proprioceptive techniques or multisensory classification techniques because the input affects the muscle spindles, the joints, the vestibular system, and possibly the auditory system with the low frequency noise. And every time vibration is applied, the skin receptors will initially fire although most will adapt quickly to prolonged use of any stimuli.
The tendon.
The tendon receptors are specialized receptors located in both the proximal and the distal musculotendinous insertions. In conjunction with the stretch receptors, the tendon plays an important role in the mediation of proprioception. , ,
The principal role of the tendon is to monitor muscle tension exerted by the contraction of the muscles or by tension applied to the muscle itself. Research has demonstrated that the tendon is highly sensitive to tension and acts conjointly with the stretch receptors to inform higher centers of continuing environmental demands to modulate or change existing plans; these higher centers in turn regulate tonicity and the state of the motor pool. , The tendon (Ib) signals not only tension but also the rate of change of tension and provides the sensation of force as the muscle is working. A fundamental difference between the tendon organ and the stretch receptors is that the stretch receptors detect length, whereas the tendon monitors tension and force. The stretch receptors regulate reciprocal inhibition, whereas the tendon modulates autogenic inhibition. Table 8.2 lists a variety of treatment approaches using the tendon to inform higher centers regarding needed changes and regulation over spinal generators.
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Maintained stretch to the tendon organ.
Maintained stretch to a muscle has the potential for triggering the tendon organ if tension is great enough. Once the maintained stretch fires the tendon organ, autogenic inhibition of the same muscle occurs. A therapist will feel a release of the agonist muscle, allowing for elongation of the contractile components. Simultaneously, the tendon organ’s sensory neurons will facilitate motor neurons to the antagonist muscle, thus heightening its sensitivity and potential for activity. This is the technique used when a joint has developed range restriction. The clinician always needs to differentiate whether the tightness found within the joint is caused by compensatory muscles considered movers protecting injured postural muscles beneath or by tightness just from positioning, disuse, or fear.
Inhibitory pressure.
Pressure has been used therapeutically to alter motor responses. Mechanical pressure (force), such as from cones, pads, or the orthokinetic cuff developed by Blashy and Fuchs, provided continuously is inhibitory. That pressure seems most effective on tendinous insertions. It is hypothesized that this deep, maintained pressure activates pacinian corpuscles, which are rapidly adapting receptors. A variety of researchers have studied these receptors and their relationship to regulating vasomotor reflexes, modulating pain, and dampening other sensory system influence on the CNS. ,
This inhibitory pressure technique also works when pressure is applied across the longitudinal axis of a tendon. The pressure is applied across the tendon with increasing pressure until the muscle relaxes. Constant pressure applied over the tendons of the wrist flexors may dampen flexor hypertonicity and elongate the tight fascia over the tendinous insertion.
Pressure over bony prominences has modulatory effects. A common example is pressure on the medial aspect of the calcaneus, which dampens plantarflexors and allows contraction of the lateral dorsiflexor muscles. Pressure over the lateral aspect of the calcaneus also dampens calf muscles to allow for contraction of the medial dorsiflexor muscles. Localized finger pressure applied bilaterally to acupuncture points has been shown to relieve pain and reduce muscle tone. This technique has also been found to be particularly effective when used in a low-stimulus environment and when combined with deep breathing. This combination of pressure (manually applied), environmental demands (low), and parasympathetic activity (slow, relaxed breathing) illustrates various systems interacting together to create the best motor response. The real world requires the patient to respond to many environmental conditions while relaxed or under stress. Thus once a patient begins to demonstrate normal adaptable motor responses, the therapist needs to change the conditions and the stress level to allow the patient to practice variability. As described, this practice should incorporate motor error, especially error or distortions in the plan, yet still achieve the desired goal. As the patient self-corrects, greater demand and variability should be introduced.
Joint receptor approximation.
Approximation of the joint mimics weight bearing and facilitates the postural extensor system, and thus use of the treatment technique is thought to improve balance. Gravity creates approximation and its greatest force is produced down through the body in vertical postures. Approximation should help to stabilize any joint that is in a load-bearing situation by eliciting coactivation of the muscles around the joint in question. In standing, gravity creates approximation down through the entire spine, hips, knees, and ankles. When in a prone position on elbows, the load goes down again through the upper spine while simultaneous going down through the shoulder girdles of both arms. If a therapist increases that load by adding pressure down through the joints in question, then an augmented intervention has been added to the therapeutic environment. Using weight belts around the waist or a weighted vest on the trunk can facilitate the postural coactivation needed during standing or walking. At times, approximation can be used to heighten normal postural tone while simultaneously dampening excessive tone in the other leg. For example, patients/clients who have CNS insult often have an imbalance in function within the two lower extremities. This can be very frustrating for the therapist because bringing the patient to standing to assist in regaining normal postural extension of one leg triggers the other into a strong extensor pattern, causing plantarflexion and inversion of that foot. One way to use approximation in treating both legs simultaneously might be to first bring the patient from sitting onto a high-low mat. Then the therapist can raise the mat high enough that the patient can be lowered into standing on the normal-functioning leg. At the same time the patient’s other leg can be bent at the knee, and that knee placed on a stool or chair. This allows approximation down through the entire leg that is in standing position while approximating the trunk, hip, and knee of the other leg in the kneeling position. The therapist can work on standing and weight shifting in one leg while dampening abnormal tone in the kneeling leg. As the kneeling leg starts to regain postural coactivation in its hip, postural function will often be felt in the knee and ankle.
Traction and distraction.
One or more joints are distracted by a force that causes it or them to separate or pull apart, similar to the swing phase of the leg during ambulation or the arms in a reciprocal pattern to each leg. This distraction of the joint receptors also puts stretch on the muscles, which combines to facilitate the pattern into which the limb is moving. Simultaneously, distraction dampens the antagonistic movement pattern, which allows the agonist movement to continue. A therapist will often use manual traction to get relaxation of hyperactive extensor muscles or for limited mobility. Often therapists do not think of the traction when applying resistance to a limb. For example, a mistake made is placing ankle weights to facilitate limbs that are ataxic. Ataxia is an imbalance in coactivation and smooth movement of both agonist and antagonist muscle groups. The weight itself slows down the excessive movement by the resistance. However, weight on the ankle creates traction that will facilitate only the flexor group and often creates an additional imbalance in the ataxic leg. When the weights are removed, the patient often is more ataxic. Table 8.3 lists a variety of treatment approaches using the joints to facilitate or inhibit motor output.
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Combined proprioceptive input techniques.
Many techniques succeed because of the combined effects of multiple inputs to the proprioceptive system of stretch, joint, and tendon receptors. Some of these combined techniques described in this section include ballistic movements; total-body positioning; PNF patterns; postexcitatory inhibition (PEI) with stretch, range, rotation, and shaking; heavy work patterns; Feldenkrais (see Chapter 39 ) ; and manual therapy. , ,
Ballistic movement.
Ballistic movements are characterized by muscle contractions that occur in very high velocities over a short period of time. They are effective because of their combined proprioceptive interaction. The patient/client is asked to quickly initiate a movement, such as shoulder flexion while prone over a table with the arm hanging over the side. This component is volitional, but the patient then maintains a passive role. As the patient relaxes, the movement patterns become automatic. The physiology behind the automatic movement is easy to understand. As the muscle approaches the shortened range, the amount of ongoing γ afferent activity decreases. Thus both the agonist α motor neuron bias and the inhibition of Ia and II receptors of the antagonistic α motor neurons decrease. Simultaneously, the antagonistic muscle is being placed on more and more stretch. This stretch, as well as the lack of inhibition on the antagonistic α motor neurons, will encourage the antagonistic muscle to begin contraction and reverse the movement pattern. The tendon organs also play a key role in ongoing inhibition. As the muscle approaches the shortened range and tension on the tendon becomes intense, the tendon organ increases its firing, thus inhibiting the agonistic muscle in the shortened range while facilitating the antagonistic muscle. This technique is highly movement oriented, and the traction applied by gravity to the shoulder joint while swinging the arm further facilitates the movement. These ballistic movements are part of the program generators within the spinal system that facilitate reciprocal movements of the limb. As the patient performs the movement, there is little need for conscious attention to drive the movement; it will run automatically. The role of the Ib fibers during this open chain or movement pattern is definitely different from its role in a closed chain or weight-bearing environment. Supraspinal influence over programmed activity also plays a role in the effectiveness of this treatment. The specific rationale for why ballistic movements have functional carryover may be explained by recent research into cerebellar function and the importance of mechanical afferent input in regulation of movement (see Chapter 19 ).
The clinician using this technique must exercise caution. ROM can easily be obtained through ballistic movement. Consequently, the clinician must always determine before therapy the reasons for specific clinical signs and whether the total problem will be corrected through an activity such as a ballistic movement. This is the diagnostic responsibility of the professional. If one component of the problem is alleviated, such as limitation of range, while other components are ignored, this can be a dangerous technique. If the lack of range is a result of muscle splinting because there is lack of postural tone or joint stability, then ballistic movement has the possibly increasing the problem. For example, assume that the rotator cuff muscles are slightly torn and the movers of the shoulder are superficially splinting to prevent further tearing. Ballistic movement that causes relaxation of more superficial muscles will place more responsibility for shoulder stabilization on the rotator cuff muscles and may increase the tear on the rotator cuff muscles causing increased pain.
Total-body positioning.
Total-body positioning implies the use of positioning and gravity to dampen afferent activity on the α motor neurons and thus cause a decrease in tone, or relaxation. Currently, the rationale for why relaxation of striated muscle occurs after this treatment implies that the effect of the flexor reflex afferents is being dampened by a combination of input and interneuronal activity. These changes in the state of the muscle tone will not be permanent and will revert to the original posturing unless motor learning and adaptation within the central programmer occur simultaneously. Thus, for this treatment to effect permanent change, a large number of systems need modification. This modification can be augmented by techniques that facilitate autogenic inhibition, reciprocal innervation, labyrinthine and somatosensory influences, and cerebellar regulation over tone. Changing the degree of flexion of the head also alters vestibular input and the state of the motor pool. But again, the patient’s CNS needs to be an active participant and will ultimately determine whether permanent learning and change are programmed.
Proprioceptive neuromuscular facilitation.
To analyze and learn the principles, techniques, and patterns that constitute PNF, a total approach to treatment, refer to the texts by Adler and colleagues, Voss, and Sullivan and colleagues. This approach is used extensively for patients with musculoskeletal and neuromuscular problems, with research on this method encompassing more populations with lower motor neuron and musculoskeletal problems than upper motor neuron lesions. , , When proprioceptive techniques are packaged in specific movement patterns, it may be referred to as PNF. When individual proprioceptive techniques are discussed alone, the specific sensory function is being acknowledged, and these techniques can be integrated into many rehabilitation intervention strategies.
Postexcitatory inhibition with stretch, range, rotation, and shaking.
The concept of PEI is based on the action potential or electrical response pattern of a neuron at the time of stimulation and on the entire phase response until the neuron returns to normal. At the time of stimulation, the action potential will build and go through an excitatory phase. The neuron then enters an inhibitory phase or refractory period during which further stimulation is not possible. This is referred to as the PEI phase or postsynaptic afferent depolarization. These phase changes are extremely short and, in normal muscle, asynchronous with respect to multiple neuronal firing. In a hypertonic muscle, more simultaneous firing occurs. When the muscle is lengthened, and thus tension is created, more fibers will be discharged. It is hypothesized that if the hypertonic muscle is placed at the end of its spastic range and a quick stretch is applied and held, then total facilitation followed by total inhibition will occur because of PEI. As the inhibition phase is felt, the therapist can passively lengthen the spastic muscle until the facilitatory phase sets in repolarization. At that time the clinician holds the lengthened position. Increased tone will ensue, followed by inhibition and continued lengthening. Holding the range (not allowing concentric contraction during the excitatory phase) is critical. If the muscle is held as the tone increases, the resistance and stretch are then maximal and probably further facilitate the inhibitory phase.
Rood’s heavy work patterns.
Rood’s concepts of cocontraction in weight-bearing positions such as on elbows, on extended elbows, kneeling, and standing blend with current concepts of motor learning. Concepts explain the rationale why postural holding in shortened range for periods of time are valid interventions. Rood stressed the need for patients to work in and out of those shortened ranges to gain postural control and to practice directing the limbs during both closed and open chain activities.
Feldenkrais.
The Feldenkrais concepts , of sensory awareness through movement place emphasize relaxation of muscles on a stretch, including distracting and compressing joints for sensory awareness. Both techniques reflect combined proprioceptive techniques. Taking muscles off the stretch slows general afferent firing and thus overload to the CNS. Compression and distraction of joints enhance specific input from a body part while simultaneously facilitating input of a lesser intensity from other body segments. This combined proprioceptive approach enhances body schema awareness in a relaxed environment. It also integrates empowerment of the patient by use of visualization and asking for volitional control. (See Chapters 27 and 39 for additional information.)
Exteroceptive or cutaneous sensory system
Differentiation of receptor site as augmented intervention.
Humans have many different types of tactile receptors. Some are superficial, and others are deep within the layers of the skin. These receptors have been identified within the chapter on motor learning. Their use as augmented intervention strategies is discussed in the following section.
A list of treatment techniques using the exteroceptive (tactile) input system as their primary mode of entry can be found in Table 8.4 . Interventions that use cutaneous stimuli include neutral warmth, light touch, and maintained pressure, among others. Specific stimuli for the varied receptors and the expected responses to cutaneous stimuli are presented in the table.
| Quick Phasic Withdrawal |
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| Prolonged Icing (Repetitive Icing Should Be Used With Caution Because of Rebound Effect) |
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| Neutral Warmth |
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| Light Touch, Rapid Stroking |
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| Maintained Pressure or Slow, Continuous Stroking With Pressure |
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* Response: adaptation of many cutaneous receptors to stimulus, thus decreasing exteroceptive input, decreasing reticular activity, and decreasing facilitation of muscles underlying stimulated skin.
Treatment alternatives using the exteroceptive system.
The function of the exteroceptive system is to inform the nervous system about the surrounding world. The CNS will adapt behavior to coexist and survive within this environment. Although many protective responses are patterned within the motor system, these patterned responses can be changed or modulated according to momentary inherent chemistry, attitude, motivation, alertness, and so on. Different from some of the other treatment approaches, the function of the exteroceptive input system is not reflexive but rather informative and adaptable.
Quick phasic withdrawal.
The human organism reacts to painful or noxious stimuli at both conscious and unconscious levels. If the stimulus is brief and of noxious quality, it will elicit a protective reaction of short duration with use of the long-chain spinal reflex loops. Simultaneously, afferent impulses ascend to higher centers to evoke prolonged emotional-behavioral responses. Stimuli such as pain, extremes in temperature, rapid movement, light touch, and hair displacement are the most likely to cause this reaction by activating free nerve endings. These stimuli are perceived as potentially dangerous and communicate directly with the reticular-activating system and nonspecific thalamic nuclei. These structures have diffuse interconnections with all regions of the cerebral cortex, autonomic nervous system (ANS), limbic system, cerebellum, and motor centers in the brain stem. Research has shown that children who exhibit hyperactive withdrawal reactions also develop negative emotional reactivity and show significantly more avoidance behavior and in time show right frontal asymmetry. These alerting stimuli have been linked to motor seizures in critically ill patients. As indicated by these research studies, therapists need to be aware of these potential responses, especially in patients with severe neurological insult that has resulted in a lower level of consciousness. These low-functioning patients cannot express their feelings nor how their nervous system is reacting to the input. Thus therapists need to be very aware of any motor response a patient may express and try to avoid using stimuli that might trigger these avoidance behaviors.
From observance of the behavior of patient’s with chronic neuropathic pain, withdrawal responses seem to become habitual and may be associated with somatosensory (S1) remapping ; thus some individuals may have difficulty with discriminating benign stimuli from potentially injurious stimuli. When any movement or touch is perceived as painful, the challenge to both therapist and patient is to agree on the therapeutic dose of a certain intervention and particular session. Therapists need to gain trust, and one way is to not elicit a lot of pain during treatment. Patient responses to pain induced during treatment such as exercise and manual therapy range can from increased patient resistance to joint and overall body movement to a complete loss of trust in the practitioner. Alami and colleagues completed a small study of patients/clients who experienced pain induced by exercise and mobilization (PIEM) during physical therapy and found that patient’s desire preintervention education about pain, their particular pain response, and how a physical therapy plan of care can be adapted according to their pain intensity.
There are some real therapeutic limitations to using stimuli that “load” the spinothalamic system. A painful stimulus will be excitatory to the nervous system and produce a prolonged reaction after discharge.
Because light touch has both a protective and a discriminatory function, techniques such as brushing or stroking the skin with a soft brush have the potential of informing the CNS about (1) texture, object specificity, and error in fine motor responses or (2) danger (eliciting a protective response). If a protective response is triggered, the specific withdrawal pattern will depend on a variety of circumstances. If the stimulus is applied to an extensor surface, then a flexor withdrawal will be facilitated. If the stimulus is placed on a flexor surface, one of two responses occurs. First, the patient might withdraw from the stimulus, thus going into an extensor pattern. Second, the stimulus may elicit a flexor withdrawal and cause the patient to go into a flexor pattern. Which pattern occurs depends on preexisting motor programming bias as a result of positioning and the predisposition of the patient’s CNS. Both responses would be considered normal. The condition or emotional state of the nervous system and whether the stimulus is considered threatening also determine the sensitivity of the response, again reinforcing the systems’ interdependence. These responses are protective and do not lead to repetition of movement or motor learning. For that reason, along with the emotional and autonomic reactions, a phasic withdrawal to facilitate flexion or extension is not recommended as a treatment approach unless all other possibilities have been eliminated.
Short duration, high-intensity icing.
Cold is another stimulus that the nervous system perceives as potentially dangerous. The use of ice as a stimulus to elicit desired motor patterns is an early technique developed by Rood and was referred to as repetitive icing. An ice cube is rubbed with pressure for 3 to 5 seconds or used in a quick-sweep motion over the muscle bellies to be facilitated. This method activates both exteroceptors and proprioceptors and causes a brief arousal of the cortex. This method can produce unpredictable results. Although initially a phasic withdrawal pattern generator response will be activated immediately after the reflex has taken place, the “rebound” phenomenon deactivates the muscle that has been stimulated and lowers the resting potential of the antagonistic muscle. Therefore a second stimulus to the same dermatome-myotome neural network may not elicit a second response. However, because of reciprocal innervation, the antagonistic muscle may effect a rebound movement in the opposite direction. Icing may also cause prolonged reaction after discharge because of the connections to the reticular system, limbic system, and ANS. Thus the ANS would be shifted toward the sympathetic end. Too much sympathetic tone causes a desynchronization of the cortex. Although the resting state of the spinal generator may be altered briefly, if the heightened state persists, the cause is most likely fear or sympathetic overflow (see Chapter 4 ). This state is destabilizing to the system and most likely will not lead to any motor learning. Because of unpredictable response patterns to Rood’s repetitive icing, this technique is seldom used.
The therapist is cautioned not to use short-duration, high-intensity icing to the facial region above the level of the lips, to the forehead, or to the midline of the trunk. These areas have a high concentration of pain fibers and a strong connection to the reticular system. ,
Ice should not be used behind the ear because it may produce a sudden lowering of blood pressure. The therapist should also avoid using ice in the left shoulder region in patients with a history of heart disease because referred pain from angina pectoris manifests itself in the left shoulder area, indicating that the cold stimulus might cause a reflexive constriction of the coronary arteries. In addition, the primary rami located along the midline of the dorsum of the trunk have sympathetic connections to internal organs. The cold stimulus may alter organ activity and perhaps produce vasoconstriction, causing increased blood pressure and reduced blood supply to the viscera. ,
Brief administration of ice can have beneficial effects if the nervous system’s inhibitory mechanisms are in place. For instance, in children with learning disabilities or adults with sensorimotor delays, the application of ice to the palmar surface of the hands will cause arousal at the cortical level because of the increased activity of the reticular activating system. This arousal response presumably produces increased adrenal medullary secretions, resulting in various metabolic changes. Therefore icing should be used selectively. If the patient has an unstable ANS, icing should be eliminated as a potential sensory modality.
Prolonged use of ice.
Physicians have used therapeutic cold for the treatment of individuals with high fever and/or intracranial pressure with the intent of reducing the body temperature or brain swelling to prevent brain damage. This procedure is done with cooling pans or blankets. Whole-body cryotherapy has been used to reduce inflammation and pain and overcome symptoms that prevent normal movement. This type of therapy consists of the use of very cold air maintained for 2 minutes in cryochambers. A recent study looked at this type of therapy for injured athletes. It was found that the procedure did not cause harm to the individual. This approach does not seem realistic for use in occupational or physical therapy clinics.
A variety of approaches that incorporate prolonged icing techniques have been used in therapy clinics for decades. The PNF approach may be the most common. Inhibition of hypertonicity or pain is the goal for the use of any of these methods. With prolonged cold, the neurotransmission of impulses, both afferent and efferent, is reduced. Simultaneously the metabolic rate within the cooled tissue is reduced (see Chapter 30 ). Caution must be exercised with regard to the use of this modality. However, for effective treatment results, the patient (1) should be receptive to the modality, (2) should be able to monitor the cold stimulus (sensory deficits should not be present), and (3) should have a stable autonomic system to prevent unnecessary adverse effects of hypothermia. Research of the past decade has consistently shown that cryotherapy is an effective tool for reducing pain and has helped individuals regain integration of axial musculature after neurological insults. Individuals of all ages seem to respond similarly, which allows therapists to use this therapeutic tool across generations.
Ice immersion of the contralateral limb was used decades ago to get a reflexive decrease in temperature in the affected limb. It was believed that this intralimb reflex was an effective way of treating pain without directly treating the limb, and recent research has validated that belief.
Ice massage is another form of prolonged icing and is often used to treat somatic pain problems. It is also used over high-toned muscles to dampen striated muscle contractions. Caution must be used when eliminating pain without correcting the problem causing pain. For example, if instability causes muscle tone and pain, then icing might decrease pain while causing additional joint instability and potential damage. The end result would be an increase, not a decrease, in pain and motor dysfunction.
Maintained stimulus or pressure.
Because of the rapid adaptation of many cutaneous receptors, a maintained stimulus will effectively cause inhibition by preventing further stimuli from entering the system. This technique is applied to hypersensitive areas to normalize skin responses. Vibration used alternately with maintained pressure can be highly effective. It should be remembered that these combined inputs use different neurophysiological mechanisms. It is often observed that low frequency–maintained vibration is especially effective with learning-disabled children who have hypersensitive tactile systems that prevent them from comfortable exploration of their environment. When children themselves use vibration on the extremities, their hypersensitive systems seem to normalize and they become receptive to exploring objects. If that exploration is accompanied by additional prolonged pressure, such as digging in a sandbox, the technique seems to be more effective because of the adaptive responses of the nervous system.
Maintained pressure approaches using elastic stockings, tight form-fitting clothing (e.g., wet suits, expanded polytetrafluoroethylene [Gore-Tex] biking clothing), air splints, and other techniques can be incorporated into a patient’s daily activity without altering lifestyle. The use of TheraTogs in children with various hyperactivity conditions has become an accepted therapeutic tool. They add some resistance, some support, and maintained pressure. TheraTogs have also been shown to be effective in assisting individuals with hemiplegia to regain abductor control.
In this way, patients can self-regulate their systems, allowing greater variability in adapting to the environment. Owing to the multisensory and multineuronal pathways used when peripheral input is augmented, traditional linear, allopathic research on human subjects is extremely difficult to design or measure with control, but outcome studies demonstrating efficacy are possible. Initially, efficacy confirmed by observation was acceptable. Concrete evidence is still scarce; repeat studies with use objective measures are needed.
Light discriminatory touch.
Once an individual can discriminate light touch both for protection and for discriminatory learning, a lot of therapeutic tools become available to the therapist. Using boxes with an opening so the individual can insert a hand and arm but cannot see what is inside, a patient can work on discriminating textures, objects, letter, numbers, and so on while working on higher-order processing. Once this touch has been integrated, the patient can also use light touch to determine balance, position in space, and various other types of perceptual tasks.
Vestibular system
Vestibular treatment techniques.
The vestibular system is a unique sensory system, critical for multisensory functioning, making it a viable and powerful input modality for therapeutic intervention. Any static position and any movement pattern will facilitate the labyrinthine system; therefore vestibular function and dysfunction play a role in all therapeutic activities. To conceptualize vestibular stimulation as spinning or angular acceleration minimizes its therapeutic potential and also negates an entire progression of vestibular treatment techniques. , , Linear movements in horizontal and vertical postures and forward-backward directions occur early in development and should be considered one viable treatment modality. These movements seem to precede side-to-side and diagonal movements, which are followed by linear acceleration and end with rotational movements. All these movements can be done with assistance or independently by the patient in all functional activities. It is important to remember that the rate of vestibular stimulation determines the effects. A constant, slow, repetitive rocking pattern, irrespective of plan or direction, generally causes inhibition of total-body responses via the α motor neuron but not the spindles, whereas a fast spin or fast linear movement tends to heighten both alertness and the motor responses. Again, the vestibular mechanism is only one of many that influence the motor system. Thus the system interaction must be constantly reassessed.
As already indicated, constant, slow, repetitive rocking patterns, irrespective of plane or direction, generally cause inhibition of the total-body responses. Yet any stimulus has the potential of causing undesired responses, such as increased or decreased tone. When this occurs, the procedure should be stopped and reanalyzed to determine the reason for the observed or palpated response. For example, assume that a patient, whether a child with cerebral palsy, an adolescent with head trauma, or an adult with anoxia, exhibits signs of severe generalized extensor hypertonicity in the supine position. To dampen the general motor response, the therapist decides to use a slow, gentle rocking procedure in supine position and discovers that the hypertonicity has increased. Obviously, the procedure did not elicit the desired response and alternative treatment is selected, but the reason for the increased hypertonicity needs to be addressed.
It is possible that the static positioning of the vestibular system is causing the release of the original tone and that through increasing of the vestibular input the tone also increases. It may also be that the facilitatory input did indeed cause inhibition but the movement itself caused fear and anxiety, thus increasing preexisting tone and overriding the inhibitory technique. Instead of selecting an entirely new treatment approach, a therapist could use the same procedure in a different spatial plane, such as a side-lying, prone, or sitting position. Each position affects the static position of the vestibular system differently and may differentially affect the excessive extensor tone observed in the patient. The vertical sitting position adds flexion to the system, which has the potential of further dampening extensor tone. This additional inhibition may be necessary to determine whether the slow rocking pattern will be effective with this patient. It would seem obvious that if a vestibular procedure was ineffective in modifying the preexisting extensor tone, then use of a powerful procedure, such as spinning, would be inappropriate. Selection of treatment techniques should be determined according to patient needs and disability. Patients either with an acoustic tumor that perforates into the brain stem or with generalized inflammatory disorders may be hypersensitive to vestibular stimulation, whereas other patient’s, such as a child with a learning disability, may be in need of massive input through this system. Heiniger and Randolph and Farber , present in-depth analyses of various specific vestibular treatment procedures commonly used in the clinic. The literature clearly establishes the causation of one vestibular imbalance, dizziness, for all age groups. Certainly individuals can have vestibular problems and will present themselves as being dizzy or hypersensitive to movement of the head.
General body responses leading to relaxation.
Any technique performed in a slow, continuous, even pattern will cause a generalized dampening of the motor output. During handling techniques, these procedures can be performed with the patient in bed, on a mat while horizontal, sitting at bedside or in a chair, or standing. The movement can be done passively by the therapist or actively by the patient. Carryover into motor learning will best be accomplished when the patient performs the movement actively, without therapeutic assistance. In a clinical or school setting, a patient who is extremely anxious, hyperactive, and hypertonic may initiate slow rocking to decrease tone or feel less anxious or hyperactive. The reduction of clinical signs allows the patient to sit with less effort and to be more attentive to the environment, thus promoting the ability to learn and adapt.
It is the type of movement, not the technique, which is critical. The concept of slow, continuous patterns is used in Brunnstrom’s rocking patterns in early sitting, in PNF mat programs, and in therapeutic ball exercise programs; the use of these patterns can be observed in every clinic. Although the therapist may be unaware of why Mr. Smith gets so relaxed when slowly rocked from side to side in sitting, this procedure elicits an appropriate response. The nurse taking Mr. Smith for a slow wheelchair ride around the hospital grounds may do the same thing. Once the relaxation or inhibition has occurred, the groundwork for a therapeutic environment has been created to promote further learning, such as learning of ADL skills. The technique in and of itself will relax the individual but not create change or learning.
Pelvic mobilization techniques in sitting use relaxation from slow rocking to release the fixed pelvis. This release allows for joint mobility and thus creates the potential for pelvic movement performed passively by the therapist, with the assistance of the therapist, or actively by the patient. This technique often combines vestibular with proprioceptive techniques, such as rotation and elongation of muscle groups, which physiologically modify existing fixed tonal response through motor mechanisms or systems interactions. Simultaneously, slow, rhythmic rocking, especially on diagonals, is used to incorporate all planes of motion and thus all vestibular receptor sites to get maximal dampening effect, whether directly through the vestibulospinal system or indirectly through the cerebellum and reticular spinal motor system. The same pelvic mobility can be achieved by placing the patient (child or adult) over a large ball. The ball must be large enough for the patient to be semiprone while arms are abducted and externally rotated, and the legs relaxed (either draped over the ball or in the therapist’s arms). Again, this position allows for maintained or prolonged stretch to tight muscles both in the extremities and in the trunk while doing slow, rhythmical rocking over the ball. The pelvis often releases, and the patient can be rolled off the large ball to stand on a relaxed pelvis preliminary to gait activities. A word of caution must be given regarding use of a large ball for relaxation. It is much easier to control the ball when someone is assisting that control from the opposite direction (in front of the patient). If slow rocking is done and the therapist is keeping his or her voice monotonous for further relaxation, the individual assisting will also relax. One author has had family members fall asleep and slowly or quickly fall to the floor.
Techniques to heighten postural extensors.
Any technique that uses rapid anteroposterior or angular acceleration of the head and body while the patient is prone will facilitate a postural extensor response. Scooter boards down inclines, rapid acceleration forward over a ball or bolster, going down slides prone, and using a platform or mesh net to propel someone will all facilitate a similar vestibular response of righting of the head with postural overflow down into the shoulder girdle, trunk, hips, and lower extremities. Rapid movements while on elbows, on extended elbows, and in a crawling position can also facilitate a similar response. Depending on the intensity of the stimulus, the response will vary. In addition, the patient’s emotional level during introduction to various types of stimuli may cause differences in tonal patterns. Clinical experience has shown that facilitatory vestibular stimulation promotes verbal responses and affects oral-motor mechanisms. Children with speech delays will speak out spontaneously and respond verbally.
Because facilitatory vestibular stimulation biases the sympathetic branch of the ANS, drooling diminishes and a generalized arousal response occurs at the cortical level. Therefore the appropriate time to teach adaptive rehabilitative techniques is after vestibular stimulation.
Facilitatory techniques influencing whole-body responses.
Tactile, vestibular, and proprioceptive inputs also assist in the regulation of the body’s responses to movement. , As stated previously, the vestibular system, when facilitated with fast, irregular, or angular movement, such as spinning, not only induces tonal responses but also causes massive reticular activity and overflow into higher centers. Thus increased attention and alertness are often the outcome. The tracts going from the spinal cord, brain stem, and higher subcortical structures must be sufficiently intact to permit the desired responses from this type of input. If a lesion in the brain stem blocks higher-center communication with the vestibular apparatus, then massive input may cause a large increase in abnormal tone. The therapist needs to closely monitor any distress or ANS anomalies.
Autonomic nervous system
The ability to differentiate tone created by emotional responses versus tone resulting from CNS damage is a critical aspect of the evaluation process. Emotional tone can be reduced when stress, anxiety, and fear of the unknown have been reduced. This is true for all individuals. The patient with brain damage is no exception. Six treatment modalities that normally produce a parasympathetic or decreased sympathetic (flight or fight) response are as follows:
- 1.
Slow, continuous stroking for 3 to 5 minutes over the paravertebral area of the spine
- 2.
Inversion, eliciting carotid sinus reflex along with other somatosensory receptors (refer to the discussion of vestibular system earlier in the chapter)
- 3.
Slow, smooth, passive and active assistive movement within a pain-free range (refer to Maitland grade II movements)
- 4.
Deep breathing exercises
- 5.
Progressive muscle relaxation
- 6.
Cranial sacral manipulation (see Chapter 39 )
When pressure is applied to both the anterior and posterior surfaces of the body, measurable reductions may be recorded in pulse rate, metabolic activity, oxygen consumption, and muscle tone. , These pressure techniques are identified as an intricate part of the many intervention approaches such as therapeutic touch, , Feldenkrais, , Maitland, massage, , and myofascial release. , , Although not verbally identified, other techniques (e.g., neurodevelopmental treatment [NDT], , Rood, , , Brunnstrom, and PNF ) also place an important emphasis on the response of the patient to the therapist’s touch.
Treatment alternatives using the autonomic nervous system
Slow stroking.
Slow stroking over the paravertebral areas along the spine from the cervical through lumbar components will cause inhibition or a dampening of the sympathetic nervous system. The technique is performed while the patient is in the prone position. The therapist begins by stroking the cervical paravertebral region in the direction of the thoracic area, using a slow, continuous motion with one hand. Usually a lubricant is applied to the skin, and the index and middle fingers are used to stroke both sides of the spinal column simultaneously. Once the first hand is approaching the end of the lumbar section, the second hand should begin a downward stroking at the cervical region. This maintains at least one point of contact with the patient’s skin at all times during the procedure. The technique is applied for 3 to 5 minutes—and no longer—because of the potential for massive inhibition or rebound of the autonomic responses. , It is also recommended that at the end of the range of the last stroking pattern, the therapist maintain pressure for a few seconds to alert both the somatic and visceral systems that the procedure has concluded. Eastern medicine recognizes the importance of the ANS in total-body regulation to a greater extent than Western medicine does. The concepts of meridians and acupressure and acupuncture points are all intricately intertwined with the ANS (see Chapter 39 ). For that reason, a technique such as slow stroking would potentially interact with meridians and does extend over the row of acupuncture points referred to as shu points and relates to visceral reflexes connecting smooth muscle and specific organ systems. It is believed that this continuous, slow, downward pressure modulates the sympathetic outflow, causing a shift to a parasympathetic reaction or relaxation. Whether a result of the pressure on the sympathetic chain, some energy pressure over meridian points, a pleasant sensation, or something unknown, slow stroking does elicit relaxation and calming. , Patients/clients with large amounts of body hair or hair whorls are poor candidates for this procedure because of the irritating effect of stroking against the growth patterns and the sensitivity of hair follicles.
Slow, smooth, passive movement within pain-free range.
Increasing ROM in painful joints is a dilemma frequently encountered by therapists caring for a patient with neurological damage. Having the patient communicate the first perception of pain and then moving the limb in a slow, smooth motion toward the pain range may elicit a variety of behaviors. In patients with fear and guarding, one strategy is for the therapist to stop the motion at the patient’s stated point of pain, then retreat back into a pain-free area, or “safety range,” then approach again, possibly with a slight variation in rotation or direction: often the patient will relinquish the safety range with improved comfort. The second finding is that if the motion toward the pain range is slow, smooth, and continuous, then frequently much of the range that was initially painful becomes pain free. The hypothesis is that slow, continuous motion is critical feedback for the ANS to handle imminent discomfort. The slow pattern provides the ANS time to release endorphins, thus modifying the perception of pain and allowing for increased motion. If the therapist stabilizes the painful joint and prevents the possibility of that joint going into the pain range, rapid, oscillating movements can often be obtained within the pain-free range. This maintains joint mobility and often, as an end result, increases the pain-free range. This technique is not unique to the treatment of individuals with neurological problems; it is often used as a manual therapy procedure. , , Furthermore, one can move slowly into a range that actually shortens muscles. If held for 30 seconds, the muscle that is too short can relax, promoting greater motion in the opposite direction. This can be called strain-counterstrain— inhibiting firing by maintaining a position of active insufficiency, making the muscle too short.
Manual therapy , , can be used to describe the pain and joint changes occurring at the joint level. As the fields of orthopedics and neurology merge into one system, with the brain acting as an organ controlling the entire system and its components, the question of whether the pain reduction is centrally or peripherally triggered may be an important one. The answer is probably both. For example, thumb pain can increase the sensation of the nervous system to the point that even cutaneous and proprioceptive receptors act as nociceptors.
Maintained pressure.
As discussed earlier, pressure has been a common technique in neurological rehabilitation. Farber discusses a variety of techniques that facilitate a reduction of tone or hyperactivity. Pressure to the palm of the hand or sole of the foot, to the tip of the upper lip, and to the abdomen all seem to produce this effect. The pressure need not be forceful, but it should be firm and maintained. This same technique is defined as inhibitory casting when applied through the use of an orthosis (see Chapter 32 ).
Progressive muscle relaxation.
Progressive muscle relaxation is practiced during both meditation and treatment approaches such as Feldenkrais. , , These methods of relaxation tend to trigger parasympathetic reactions, which in turn slow down heart rate and blood pressure and trigger slow, deep breathing (see Chapters 16 and 39 ). The Alexander technique has also been shown to cause relaxation while simultaneously increasing postural tone.
Treatment considerations using olfactory, gustatory, auditory, and visual systems. Boxes 8.2 to 8.5 present a summary of treatment considerations using the olfactory, gustatory, auditory and visual systems.
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