Rabu, 05 Desember 2007

Athletes With Disabilities

Background

Adapted sports were introduced in the mid twentieth century as a tool for rehabilitation of injuries in war veterans. Over time, adapted sports have grown in popularity. People with disabilities now can participate on the recreational level as well as the international competitive level. In many sports, such as archery, athletes who are disabled can participate side-by-side with athletes with able bodies. Adapted equipment also allows athletes with disabilities to engage in other activities.

Organized activities for individuals with disabilities date back to 1888 when the first sport club for the Deaf was established in Berlin, Germany. In 1924, the first international competition for athletes with physical disabilities, the International Silent Games, was held. Wheelchair sports were developed at the Stokes Mandeville Hospital in the mid-1940s. The first Stoke Mandeville Games for the Paralyzed, which had 16 participants in wheelchair basketball, archery, and table tennis, were held in 1948.

The First Winter Paralympic Games were held in 1976 and were hosted in Ornskoldsvik, Sweden. The events were composed of Nordic and Alpine skiing. As with the increased number of events added to the summer Paralympic Games, events such as speed skating, sit skiing, sledge racing, and sledge hockey were added to subsequent winter games. In the Lillehammer Paralympic Games, held in Norway in 1994, events for athletes with cerebral palsy were added. In 1998, events for participants with mental disabilities were added to the winter games in Nagano, Japan.

Legislation

Legislation has helped to stimulate the development of adapted sports in the United States. In 1973, the Rehabilitation Act stated that no person could be excluded from participation in any program or activity receiving federal financial assistance. This law made physical education academic programs and intramural and interscholastic sports programs at colleges and universities accessible to participants with disabilities.

The Amateur Sports Act (1978) and the Olympic and Amateur Sports Act (1998) recognized athletes with disabilities as part of the Olympic movement. As a result, 7 organizations of disability sports hold membership in the United States Olympic Committee (USOC): USA Deaf Sports Federation, Disabled Sports USA, Dwarf Athletic Association of America, Special Olympics International, US Association for Blind Athletes, US Cerebral Palsy Athletic Association, and Wheelchair Sports USA.

In 1990, the Americans with Disabilities Act (ADA) was passed into law, providing increased access for persons with disabilities to employment, transportation, public accommodations, state government, local government, and telecommunications. In general, this access facilitates the involvement of people with disabilities in athletic pursuits and the venues where they are held. For children and adolescents, the 1990 Individuals with Disabilities Education Act (IDEA) is particularly relevant. The purpose of the IDEA is to assure access to public education for children with disabilities. This law specifically requires that children with disabilities have access to adapted physical education.

MEDICAL CONSIDERATIONS OF ADAPTED SPORTS

The role of the health care provider for athletes who are disabled is to be knowledgeable of the individual's primary disability and to assist in safe participation in sports for achievement of athletic goals. Performing a preparticipation examination (PPE) and being knowledgeable about participation maintenance and disability-specific conditions are essential to the safety of the patient. The PPE and participation maintenance are discussed in this section, while disability-specific conditions are addressed in the following section.

The PPE

Prior to participating in athletics, the athlete with a disability has to have completed acute rehabilitation, must understand the disability, must set sport-specific goals, and must communicate with a health care provider familiar with the medical aspects of the disability. A PPE performed by a qualified health care provider often is required prior to participation. The specific elements required in the PPE are determined by the sport, the level of participation, the athletic organization, the clinical indications, and the athlete. This published information is obtained from the respective athletic teams, schools, and organizations and, hence, is used by the examiner to tailor the PPE accordingly. The PPE should fulfill the requirements of the particular governing organization of the sport. Moreover, it should provide information to guide the athlete, trainer, coach, and team physician toward safe participation, activity limitations, and disability-specific training.

The objectives of the examination include the following:

  • Identify conditions that 1) may require further medical evaluation before the athlete enters into training, 2) require close supervision during training, and 3) may predispose to injury.



  • Determine the athlete's general health to assess fitness level and performance



  • Counsel on health-related issues and methods for safe participation



  • Provide referral for identified conditions that require further evaluation and/or monitoring to physicians familiar with the disability and the management of the identified conditions

In general, components of the PPE include a disability and sports-specific history and physical examination. In addition to the standard components of a history, the elements of the history for an athlete with a disability also should include athletic goals of the individual, the predisability and present level of training and sports participation, information on any over-the-counter (OTC) agents taken, presence of impairments, past family cardiopulmonary history, level of functional independence for mobility and self-care, and needs for adaptive equipment.



In addition, the review of systems (ROS) permits a comprehensive overview of the examinee's general condition. For example, in addition to the standard ROS, the examiner documents the presence of external devices for bladder drainage for the genitourinary system; for the gastrointestinal system, external devices for bowel evacuation; for the musculoskeletal system, splints and bracing equipment; and for the dermatological system, wound dressings and pressure sores.

The elements of the disability and sports-specific physical examination are tailored for the individual. Sensory deficits, neurologic deficits, joint stability and ROM, muscle strength, flexibility, skin integrity, medications, and adaptive equipment needs must be assessed. For the athlete who is disabled, assess the functional limitations of his or her body in both the affected and unaffected anatomical areas. Evaluate the patient's mobility with a wheelchair or any assistive devices that will be used for sports participation. Also evaluate his or her general cognition, memory, and judgment.

During the musculoskeletal examination of an athlete who uses a wheelchair, evaluate the stability, flexibility, and strength of the commonly injured sites (eg, shoulder, hand and wrist, lower extremities) as well as the trunk. During the musculoskeletal examination of an individual who has had a lower extremity (LE) amputation, assess the stability, flexibility, and strength of the trunk, as well as the hip girdle and the unaffected and affected LE with or without the prosthesis. For individuals with upper extremity (UE) amputations, the stability, flexibility, and strength of the shoulder girdle must be assessed in the unaffected and affected extremity with and without prosthesis, in addition to a trunk and LE evaluation. For the athlete with brain injury, stroke, or multiple sclerosis (MS), it is prudent to assess the limitations of the unaffected and affected areas based on mobility and sports-specific tasks.

Cardiovascular and pulmonary examinations are vital to any PPE and can identify conditions that can cause cardiopulmonary collapse or disease progression. Suggested guidelines for cardiovascular screening of the athlete are available from the American Heart Association, American College of Cardiology, and American College of Sports Medicine. For example, in the case of detected heart murmurs, the athlete is informed and is referred to his/her primary physician for consideration of an electrocardiogram and echocardiogram before the beginning of the sports season and before entry into training.

A PPE is performed upon entry into sports and should be repeated at least every 2-3 years. An interim follow-up prior to each sport season may be necessary if the athlete's health condition changes.

Participation maintenance

The key to continued participation and recreational enjoyment is remembering that safety is integral to good training and play. Therefore, strategies to prevent injury are emphasized.

Musculoskeletal injury is the most common injury reported among athletes who are disabled. A prevailing preventive strategy for musculoskeletal injury is sports-specific conditioning, along with preexercise stretching and warm-up as well as postexercise cool-down and stretching. Musculoskeletal injuries, as well as fatigue and exhaustion, can be reduced by assuring adequate nutrition and fluid status. Instruction in the use of proper protective and adaptive equipment and clothing also is important. In addition, the location where the sporting event is to be held should be evaluated prior to each training and play for potential hazards, such as falls, and for access and maneuverability of adaptive equipment.

Training athletes who are disabled on specific fall techniques (ie, safe methods for falling and recovering from a fall) can prevent potential injuries. This part of the athlete's education can be performed by a trained physical therapist. For example, an athlete who uses a wheelchair should be taught techniques for how to protect the head and neck in the event of a fall from a wheelchair, how to prevent ejection from the wheelchair upon a fall, and how to recover to an upright position in an energy-efficient way with a locked wheelchair.

DISABILITY-RELATED MEDICAL CONDITIONS

Environment

Thermoregulatory dysregulation is a common condition for a number of neurologic disabilities such as spinal cord injury (SCI), MS, brain injury, and stroke. For these disabilities, thermoregulatory dysregulation is a condition whereby the thermoregulatory system is impaired neurologically, resulting in heightened difficulties with acclimatization to either a cold or hot environment. Hence, the play environment heavily influences the schedule for training and for the sporting event, whether the sport is played indoors or outdoors.

In individuals who are neurologically intact, body temperature is regulated by the interplay coordinated by the autonomic nervous system, thermal receptors, cardiopulmonary system, and skeletal muscle contraction. The hypothalamus is the thermoregulatory center. The afferent system to the hypothalamus is provided by peripheral and central thermal receptors; the efferent signal descends primarily through the brainstem to the thoracolumbar division of the autonomic nervous system. The efferent system coordinates adjustments in cutaneous blood flow, sweating, venous return, and skeletal muscle-generated metabolic heat. Circulating vasoactive substances and local mechanisms are known to play a role in thermoregulation in response to the ambient temperature.

For patients with SCI, thermoregulatory dysregulation is a significant aspect in participation of sports. This dysregulation has been described at the level of the afferent and efferent systems with autonomic dysfunction and sensory deficits and at the thermoregulatory center with the impaired response to the hypothalamus regulation. Individuals with a neurologic injury level of T6 and above are most vulnerable to complications related to heat or cold stress. An impaired cooling mechanism results from the loss of the sympathetic system above the lesion, which reduces the sweating capability. The autonomic dysfunction below the lesion and the limited skeletal muscle pump function associated with weak or paralyzed muscles together impair blood redistribution and decrease venous return. Adding to the equation, the increased metabolic heat generated by skeletal muscles in exercise provides added potential for complications related to thermoregulatory dysfunction.

Thermoregulation dysfunction may occur in persons with central nervous system (CNS) lesions along the thermoregulatory system, such as in the hypothalamus or brainstem, as observed in individuals with cerebral palsy or in individuals following a stroke or brain injury. Individuals with MS may have CNS and/or spinal cord lesions; therefore, impairment of the thermoregulation system also may be observed in cases of MS. In addition, among individuals with MS, the propensity of fatigability with activity increases the risk for intolerance to environmental stresses.

With advanced age, an athlete with a neurologic physical disability may experience greater intolerance to environmental stresses than an individual without the disability. This change may occur in the setting of a previous state of immobility, premorbid deconditioning, medication effects, and concomitant age-related medical problems including autonomic dysfunction, altered control in cutaneous vasodilation, impaired renal function, reduced stroke volume and cardiac output, reduced total body water, obesity, or altered vital capacity (VC). If the individual enters into recreational athletics without prior experience and is deconditioned at the onset of training, the intolerance is even more prominent. A program geared toward a gradual acclimation is advisable.

Medications may potentiate environmental intolerance. Adjustments may need to be made, depending on the intensity of the activity. For example, diuretics can increase the risk of dehydration, especially when coupled with intense exercise. Other medications include anticholinergics, neuroleptics, antihistamines, and beta-blockers.

Prevention is the key to management. Daily assessment of the training and sporting environment should guide scheduling. Clothing featuring the appropriate fit and durability is emphasized, with the selection of lightweight light-colored garments for hot climates and insulated layered garments for cold climates. Adequate nutrition and hydration is particularly important for players in competitive games and outdoor sports. An enclosed facility such as a tent provides an area for rest and protection during breaks and for first-aid administration. Comprehensive preparation would not be complete without the identification of easy access to advanced medical services, ambulance services, and a hospital. This organizational structure is essential as athletes who are neurologically disabled are at increased risk for complications related to thermoregulatory dysfunction that may require emergent advanced medical services.

Education is vital for the athlete and game officials to prevent, identify, and provide initial management of heat-related and cold-related illnesses. In addition to prevention and recognition, medical personnel should be familiar with advanced treatment of these conditions.

Heat-related illness includes a spectrum of conditions (eg, heat-induced peripheral edema, heat cramps, heat exhaustion, hypotonic fluid-induced hyponatremic collapse, heat syncope, heat stroke). Heat edema results from local peripheral vasodilation, sweating, and increased sodium and water retention leading to the development of peripheral edema. Heat edema resolves over several days during acclimatization. The differential diagnosis of distal peripheral edema in the athlete with neurologic disability is lengthy and may need further consideration if there is a high clinical suspicion of serious conditions (eg, complex regional pain syndrome, compartment syndrome, fracture, ligament sprain, myositis ossificans, heterotopic ossification, deep vein thrombosis, heart failure, hypoalbuminemia, renal failure, infection).

The term heat cramps refers to the muscular spasm associated with prolonged exercise in heat, thought to result from ongoing negative sodium balance related to endurance activities in those who are unacclimated. Although resolution is observed with minimal conservative treatment, heat cramps may portend heat exhaustion when treatment is not administered and the athlete is not monitored for the development of further signs and symptoms of heat-related illness.

Heat exhaustion is a serious condition resulting from severe dehydration and/or hyponatremia. Tachycardia, high core temperature, dry mucous membranes, and hypotension are observed. Sweating may be reduced. If not treated, this condition may progress to heat stroke. Heat syncope results from impaired CNS perfusion due to reduced cardiac output from reduced venous return associated with heat-induced peripheral vasodilation and blood pooling in the extremities. If an alternative etiology of the syncope is suggested, the differential diagnosis for syncope in the athlete with a neurologic disability should be considered, depending on the individual's medical history and clinical presentation. The etiology may be cardiovascular, pulmonary, or associated with an acute CNS event.

Heat stroke is a medical emergency and does not resolve spontaneously. This condition results from thermoregulation failure and presents with an extremely elevated core body temperature and electrolyte and metabolic derangements. Mental status changes are key clinical clues. The Table provides a summary of the heat-related illnesses.

Heat-Related Illness

Condition Heat-induced peripheral edema Heat cramps Heat exhaustion Hyponatremic collapse Heat syncope Heat stroke
SymptomsDistal UE and LE edema; transientPainful muscle group; sudden onsetFatigue, increased weakness, sweating, nonspecific symptoms, confused



Lightheadedness or fainting in the setting of end of intense activity, dehydration, or entering into a hot area from the coldMental status changes, diarrhea, vomiting, feverish, reduced sweating
Essentials to treatmentRest and evaluation of the edematous extremityRest, massage affected muscles, oral hypotonic solutionRest, cooling, hypotonic fluid and electrolyte replacement, monitor symptomsRest, cooling, measure serum electrolytes, intravenous fluidsRest in a cool area, evaluate for other etiologies of syncope, move to a reclined position, hydrationAssess ABCs, rest, cooling, immediate emergency services evaluation

Cold-related illness can be seen with swimming, during inclement weather in summer sports, or during winter sports. The predominant condition is hypothermia. Hypothermia, by definition, occurs when the core temperature is below 95°F (35°C). Assess the degree of severity of the cold-related illness. A mild condition can be treated with slow external rewarming techniques. A moderate or severe condition requires close monitoring of the condition and warrants immediate transfer for more extensive medical attention. Until emergency services are available, initial treatment is instituted, involving removal of the athlete from the cold environment and passive external rewarming techniques.

Spasticity

Spasticity is defined as the velocity-dependent increase in resistance of muscle tone believed to be due to increased motoneuronal excitability and enhanced stretch-evoked synaptic excitation of motoneurons from an upper motor neuron injury. When not controlled, the clinical result is reduced mobility and ability to perform activities of daily living (ADL). The individual may report an inability to operate a manual wheelchair, ambulate, fit clothing properly, or perform transfers and ADL. Increased risk of contractures, skin breakdown, and pain accompany spasticity. Moreover, training and sporting events may become unsafe with the potential propulsive force of involuntary muscle spasms causing, for example, falls out of the wheelchair, difficulty in ambulation with forward movement, and reduced control of balance.

Spasticity is observed in varying degrees among patients following SCI, stroke, and brain injury and among individuals with MS. Control of spasticity is preferred when play and functional ability are affected. Management is achieved through noninvasive means with pharmacologic treatment, positioning, or bracing.

Pharmacologic options depend on the patient and the severity of the tone. Administration of medications is performed best under the advisement of a physician familiar with spasticity treatment. Medication side effect profile and dosage should be reviewed, as alertness, cognition, and motor strength can be affected adversely at therapeutic dosages. The choice, route, and dose of medication should be reviewed with the choice of optimal administration to produce the fewest side effects with the greatest control.

When indicated, bracing of the affected extremities may include tone-reducing upper extremity or lower extremity braces. For athletes who use wheelchairs, wheelchair positioning and modified components can reduce triggering muscle spasms and provide increased support in case of a triggered spasm. Trials can be performed to determine the optimal wheelchair system for the athlete. Depending on the location and severity of the spasticity, these trials can be conducted with one or a combination of items, including modification of the front rigging, adjustment of footplates, adjustment of the angle of the seat with the back support, and/or addition of a lap belt or chest, thigh, knee, ankle, and/or foot straps.

Osteoporosis

In addition to the primary and secondary osteoporosis risk factors, osteoporosis in those who are neurologically disabled is observed associated with one or a combination of factors, including immobility, decreased muscular strength and weight-bearing activities, age, predisposition, and medication. In this population, varying degrees of osteoporosis commonly are encountered among athletes with a motor complete SCI and/or advanced age. The impact on the ability to play is notable because of an increased risk of fractures over osteoporotic areas.

Preventive strategies against complications are essential for the management of osteoporosis among these athletes. Pharmacologic treatment includes recommendation of calcium and vitamin D as initial agents. The addition of bisphosphonates to treat documented osteoporosis is indicated. Modifications to equipment are prudent.

For athletes who use wheelchairs, liberal chair padding provides increased protection in case of falls and reduces the stress with axial loading. Fall prevention techniques also are implemented. These techniques include assessing the play environment for potential obstruction to safe mobility and ambulation; providing advanced training in safe mobility on uneven surfaces, stairs, and sport-specific environments; and ensuring optimal treatment for sensory deficits, such as updated prescription lenses fitted for sports activity.

In addition, it is important to assess the individual athlete's needs, as well as to provide athlete and caregiver education about the routine evaluation of the integrity, functional utility, and sports-specific applicability of the athlete's equipment, including adaptive equipment, wheelchair, ambulatory equipment aids, and/or protective gear. Repairs, adjustments, and new equipment are considered to reduce risk of falls and ensure safe play.

Musculoskeletal injuries

Musculoskeletal injuries are the most frequently reported medical problem within the competitive arenas. The shoulder was the most commonly injured area of the body in the Paralympic 1996 summer games for the athletes of the Disabled Sports USA and the Wheelchair Sports USA. Overall, from 1990-1996, among US athletes with disabilities participating the Paralympics and World Championship Games, the most commonly reported musculoskeletal injuries were the thorax/spine (13.3%), the shoulder (12.8%), and the lower leg/ankle/toes (12%). For athletes with amputations and other ambulatory athletes, LE injuries were the most commonly treated condition. For athletes using wheelchairs, UE injuries were the most commonly treated condition.

Little information has been published regarding the prevalence of injury among participants in all winter sports. Depending on the sport and the nature of the athlete's disability, as well as the method of reporting, varying prevalences of anatomic sites of injury are indicated in the literature.

Preventive strategies are essential to reduce the number of musculoskeletal injuries. Elements of management were discussed previously. This section focuses on one of the elements (ie, sport-specific conditioning). This specific type of conditioning provides the athlete with an individualized program that prepares him/her for the sport's unique metabolic and biomechanical demands, injury risks, and level of fitness. The overall program goal is to improve performance and prevent injury. The conditioning program begins with the identification of the athlete's goals and choice of sport. Each program is geared to the individual's level of fitness upon entry.

With general athletic fitness as the foundation, training for the higher level of fitness needed for that given sport incorporates flexibility, muscular strength, muscle balance, aerobic endurance, speed, agility, and sports-specific skills. Conversely, for individuals with neurologic disabilities, overtraining is a major concern. These athletes are predisposed to chronic repetitive strain and overuse injuries because of the reliance on the remaining functional limb(s). For athletes with SCI using wheelchairs, chronic shoulder injuries are common occurrences that may, in large part, be due to overuse and overtraining. Hence, it is important to strike a balance between carrying out the appropriate training program and overtraining. Precautions to prevent fatigue also are presented for athletes with MS and neuromuscular disorders.

The training program is divided into phases (eg, off-season, preseason, early season, late season). The program may be gradual in intensity and of longer duration for the elite athlete, in comparison with the recreational athlete whose play season is often shorter.

Pressure sores

A pressure sore is the disruption in skin integrity due to unrelieved pressure. Unrelieved pressure can cause local ischemia and subsequent tissue damage. Interruption in skin integrity can be associated with prominent bony surfaces, which are more likely to encounter pressure forces, poor skin integrity, and friction generated by shearing forces. The skin lesion is graded upon the depth of tissue involvement. The following classifications are according to the National Pressure Ulcer Advisory Panel:


  • Grade 1 - Nonblanchable erythema



  • Grade 2 - Partial thickness breakdown through the epidermis



  • Grade 3 - Full thickness breakdown at the dermis into the subcutaneous tissue



  • Grade 4 - Deep tissue breakdown to the fascia, muscle, bone, or joint

For individuals who use a wheelchair for mobility, the commonest areas at risk for pressure sores include the sacrum and coccyx, ischial tuberosity, posterior knee, foot, and shoulder blade. For the individual who wears a prosthesis, the skin areas in contact with the prosthesis and suspension are at risk.

Athletes with sensory deficits are most at risk for the development of pressure sores related to training or play. Other risk factors include activity-related shearing; axial forces generated against the skin; and poor transfer techniques, pressure relief techniques, seating and/or prosthetic systems, skin integrity, or skin care. Athletes who use a wheelchair and athletes who have had an amputation are at risk because of a combination of these factors.

Prevention and early intervention are important to management of pressure sores. Skin checks and pressure-relieving techniques should be performed on a regular basis. For athletes who use a wheelchair, weight shifts are the predominant pressure-relieving technique taught during rehabilitation. Weight shifts from a seated position are performed by pushing up off the surface or by leaning forward or laterally. The SCI clinical practice guidelines recommend that weight shifts be performed every 15-30 minutes to reduce the effect of prolonged pressure.

Education is directed toward assuring the adequate type, condition, and fit of adaptive devices; implementing proper transfer techniques; monitoring of disrupted skin integrity areas; and treating pressure sores early to prevent progress. For athletes who use wheelchairs, alternative adjunctive preventive strategies include methods to reduce friction forces and moist skin environments. These strategies can be achieved by choosing moisture-wicking clothing, an adequate custom-fitted wheelchair cushion, and sufficient padding over potential areas of breakdown. Sitting times may need to be restricted in severe cases.

For the athlete with an amputation, adjunct strategies include a proper prosthetic fit and an adequate suspension system, as well as assessment for a silicone liner, adequate cushioning with socks and padding, and sports-specific biomechanics training with the prosthesis. Avoiding a moist skin environment over the residual limb reduces the risk of skin breakdown.

Syncope

Syncope is the complete loss of consciousness and postural tone with recovery. A near-syncopal event represents an altered level of consciousness rather than a complete loss of consciousness. Evaluation indicates the need for assessment and treatment on an emergency basis. The main categories of the differential diagnoses include vascular, cardiac, neurologic, and miscellaneous. The differential diagnosis is lengthy and beyond the scope of this article. This section only highlights several conditions.

The most worrisome etiology is cardiogenic syncope, leading to cardiac arrest from arrhythmias, myocardial ischemia, or myocardial infarction. Hence, it is important to identify accessible emergency medical services and a hospital prior to a training session or game.

Sudden cardiac death is a separate entity defined as a nontraumatic unexpected cardiac event resulting in cardiac arrest and death within 6 hours of a previously witnessed healthy state. For the pediatric population, this phenomenon has been associated with congenital cardiac anomalies, hypertrophic cardiomyopathy, increased cardiac mass, Marfan syndrome, myocarditis, long QT syndrome, severe valvular disease, use of drugs, severe bronchospasm, and coronary artery abnormalities (less commonly). For the adult population, the occurrence of sudden cardiac death is associated primarily with coronary artery disease, but it also can be associated with hypertropic cardiomyopathy, increased cardiac mass, severe valvular diseases, conduction abnormalities, severe bronchospasm, and drug use.

The most common etiology of syncope in the athlete is neurocardiogenic syncope (vasovagal or neurally mediated hypotension syncope). A specific trigger usually is identified and can be a cough, micturition, bowel evacuation, or a stressful event. Neurocardiogenic syndrome involves a reflex-mediated vascular condition. Tilt-table testing administered by a cardiologist can reproduce it. Pharmacologic intervention may be warranted.

Syncope or near-syncopal events readily reversible in the athlete include heat-related illness, hypovolemia due to dehydration, and hypoglycemia. These conditions are treated accordingly.

The differential diagnoses of syncope in athletes who are disabled include neurologic physical disability-related syncope or near-syncopal events, which may result from a number of conditions, including hypovolemia, orthostatic hypotension, seizure, transient ischemic attacks (TIAs), or stroke. These conditions are treated accordingly. For example, among athletes with SCI, orthostatic hypotension commonly can be encountered despite the patient being in a euhydrated state with neither new neurologic changes nor evidence of seizure; stroke; or cardiopulmonary, hematologic, or musculoskeletal abnormality. Theories suggest a diminished cerebral blood flow with an impaired system to autoregulate to especially positional changes. This impaired system implies an impaired autonomic system, in addition to the reduced skeletal muscle pump function by paralyzed lower extremities, leads to decreased venous return and blood volume pooling in the lower extremities.

Management involves preventive measures such as local mechanical support (the application of supportive pressure gradient stockings and abdominal binders when the patient is in an upright position). If these conservative measures fail, pharmacologic interventions are considered and include agents such as sodium chloride tablets or midodrine.

Autonomic dysreflexia

Autonomic dysreflexia (AD) is a medical emergency resulting from the massive reflex sympathetic discharge occurring in patients with SCI at or above the splanchnic outflow at T6 level or among those with brainstem lesions. The clinical picture is an unopposed sympathetic discharge below the lesion and prevailing parasympathetic outflow above the lesion. Noxious stimuli are the triggers of AD. Therefore, in the presence of a trigger, an individual with a SCI at or above T6 may present with AD.

Clinical signs of AD include sympathetically induced elevated systolic blood pressure greater than 20 mm Hg above baseline, severe peripheral vasoconstriction, and piloerection below the lesion and parasympathetic-induced profuse sweating and skin flushing due to the vasodilation. The individual commonly complains of a severe headache, nasal congestion, and feelings of apprehension. The complications of unresolved AD are the same as for other hypertensive crises: stroke, seizure, arrhythmias, myocardial infarction (MI), and death.

Triggers for AD include some form of noxious stimuli, most commonly of a genitourinary (eg, urinary tract infection, bladder distention) or gastrointestinal (eg, constipation) origin. Other etiologies that may be encountered on the field include infection, sunburn, contact with sharp objects, tight garments, an ingrown toenail, fracture, appendicitis or other abdominal pathology, malpositioning, and disrupted skin integrity from numerous etiologies.

Initial management focuses on the identification and removal of the trigger, which usually results in its resolution. Elevating the head and trunk to more than 30° is an initial maneuver to decrease the high blood pressure. Assessing for adequate bladder drainage and an aggressive bowel evacuation, loosening tight garments, adjusting the athlete's position, and performing a full skin examination are essential in identifying the cause of AD.

Blood pressure is monitored every 5-10 minutes until it normalizes to the patient's baseline. If the systolic blood pressure does not resolve spontaneously, pharmacologic intervention is warranted until the trigger is identified and treated. The initial choice is nitropaste applied to the skin, commonly on an upper extremity, chest wall, or forehead. Doses are elevated until resolution. A hypertensive urgency or emergency may develop if these conservative measures fail. In these cases, emergency medical services are required to transfer the athlete for an in-hospital evaluation.

The athlete, coach, and officials should be familiar with preventive strategies as they can address many of the potential triggers. These strategies include assuring a functioning and secure bladder drainage system, regular bowel evacuation, routine skin examination, well-fitted adaptive devices, proper clothing, sunburn protection, and proper positioning (eg, wheelchair seating system for athletes who use wheelchairs).

Boosting

Boosting is the colloquial terminology for self-induced AD identified as a performance-enhancing technique. The term boosting refers to a technique potentially employed by athletes with SCI at T6 or above. The clinical result is similar to that produced by ergogenic aids. Consequently, boosting has been prohibited because of its unethical use in competitive sports. In theory, the performance-enhancing physiologic mechanism has been attributed to increased cardiopulmonary effects, oxygen utilization, and noradrenaline release. Reported methods for boosting by some athletes include temporarily occluding one's own urinary catheter, ingesting great amounts of fluids prior to the sporting event to distend the bladder, tightening garments, and prolonged sitting, thus inducing nociceptive stimuli. The complications of a prolonged boosting trial are the same as for AD in general (eg, stroke, seizure, arrhythmias, MI, death).

Education of medical personnel, coaches, and officials about this performance-enhancing technique is essential to its detection. Discouraging the use of practices intended to induce symptoms of AD is important. Assessing the athlete's condition prior to and during sporting events can help to detect such dangerous practices.