AAOS Comprehensive Orthopaedic Review

Section 5 - Sports Medicine

Chapter 47. Medical Aspects of Sports Participation

I. Preparticipation Physical Examination

A. Objectives


1. The goal of the preparticipation physical examination (PPE) is to identify injuries or medical conditions that place the athlete at risk during participation in athletics.


2. Focus of the PPE


a. To detect life-threatening conditions that may be exposed during activity


b. To detect current injuries that may need treatment prior to seasonal play


c. To provide a forum to discuss preventive care


d. To meet legal and insurance requirements for the institution


B. History


1. Medical history alone may identify up to 75% of conditions that would prohibit sports participation in athletes.


2. For many lethal conditions, physical examination findings may be normal. Family history and specific focus on past symptoms may provide the only clues to an underlying disorder.


3. History should include past medical problems, including recent and chronic illness and injuries.


4. Medication and supplement use should be reviewed to determine appropriate management of illness as well as identify use of banned substances.


5. Cardiovascular history


a. The cardiovascular history should include family history of sudden death, Marfan syndrome, long QT syndrome, hypertrophic cardiomyopathy (HCM), etc.


b. Exertional symptoms of syncope, dizziness, chest pain, palpitations, or shortness of breath should raise concern.


6. Neurologic history


a. The neurologic history should include previous head injuries, concussions, seizures, burners/stingers, and spinal trauma.


b. Patients with these prior conditions may be at increased risk for additional injury.


7. Athletes with prior history of heat-related illness should be screened for risk factors and counseled on preventive measures.


8. Female athletes should be questioned on history of stress fractures, missed or abnormal menses, and disordered eating habits (female athlete triad).


C. Physical examination


1. The musculoskeletal examination should focus on areas of previous injury.


2. A focused cardiovascular examination is important.


a. Blood pressures must be interpreted on the basis of patient's age, sex, and height.


b. In general, pressures >140/90 should be further evaluated.


3. Symmetric pulses in all four extremities should be noted.


4. Auscultation of the heart should be performed with the patient standing, squatting, and supine. Murmurs that worsen with standing or the Valsalva maneuver, any diastolic murmur, and systolic murmurs greater than 3/6 in intensity should be evaluated further before clearance to play.


5. Routine screening with 12-lead electrocardiography and echocardiography is not recommended by the American Heart Association. However, these tests can be useful in assessing athletes thought to be at higher risk based on history or physical examination.

II. On-Field Management

A. Unconscious athlete


1. Immediate assessment should include evaluation of the patient's airway, breathing, and circulatory status (ABCs), with spinal immobilization.


2. A cervical spine injury should be assumed in any unconscious athlete.


3. If a player is found lying prone, he or she should be log-rolled into the supine position in a controlled effort directed by the person maintaining airway and cervical alignment.


4. Face masks should be removed to allow access to the airway; however, the helmet and shoulder pads should be left in place.


5. The helmet should be removed only if the head and cervical spine are not stabilized with the helmet in place, or if the airway cannot be maintained with the helmet in place. Shoulder pads should be removed with the helmet to prevent spinal malalignment.


6. The patient should be log-rolled or placed on a spine board using the five-man lift and secured in position with straps. The head and neck should be stabilized on either side with blocks or towels.


7. Standard ACLS (advanced cardiac life support) and ATLS (advanced trauma life support) protocols including rescue breathing, cardiopulmonary resuscitation (CPR), and use of the AED (automated external defibrillator) should be performed in the apneic and pulseless patient.


B. Neck injury


1. Spinal injuries should be assumed in the unconscious or altered level-of-consciousness athlete. Spinal injuries should be suspected in the athlete with neck pain, midline bony tenderness on palpation, neurologic signs or symptoms, or a severe distracting injury.


2. On-field assessment should include the ABCs with spinal stabilization until proven otherwise.


3. The posterior neck should be palpated for step-offs, deformities, and/or tenderness.


4. Transient quadriplegia is a neurapraxia of the cervical cord that can occur with axial loading of the neck in flexion or extension.


a. Symptoms are bilateral upper and lower extremity pain, paresthesias, and weakness that by definition are transient and recover typically within minutes to several hours.


b. Athletes with transient quadriplegia should have the spine stabilized until additional imaging can be obtained to rule out fractures and spinal cord abnormalities.


5. Decisions regarding return to play after an episode remain controversial. The use of MRI or CT myelogram to rule out functional stenosis or loss of cerebrospinal fluid around the cord has been advocated.


C. Head injury


1. Approximately 300,000 sports-related brain injuries occur in the United States every year.


2. Traumatic head injury is the leading cause of death due to trauma in sports.


3. Severe head injuries in the unconscious or severely impaired athlete, including subdural hematomas (most common), epidural hematomas, subarachnoid hemorrhages, and intracerebral contusions, should be ruled out with a noncontrasted head CT.


4. A concussion is defined by the American Academy of Neurology as "a trauma induced alteration in mental status that may or may not be associated with a loss of consciousness."


5. Headache and dizziness are the most common symptoms in concussion; however, the clinical presentation can be extremely varied.


6. Loss of consciousness occurs in fewer than 10% of concussions.


7. On-field evaluation should include assessment of ABCs with spinal precautions, level of consciousness, symptoms, balance, memory (antegrade and retrograde), sensory and motor function, and thought process.


8. Athletes with severe, persistent, or worsening symptoms should be triaged to a medical center for further evaluation.


9. Concussion grading scales and other guidelines for return to play have been published but not validated. New guidelines suggesting a stepwise return to physical activity based on recurrence of symptoms have been suggested.


10. Experts agree that all symptomatic players should be withheld from activity and return-to-play decisions should be individually based.


11. Use of neuropsychological testing for evaluation of concussion and assistance with return-to-play decisions is promising and can be a helpful adjunct.


D. Orthopaedic emergencies


1. Orthopaedic injuries are the most common injuries encountered in athletes.


2. It is important to fully evaluate the athlete for potentially life-threatening injuries that may be recognized late due to focusing on obvious deformities to the extremities.


3. Fractures


a. No athlete should return to play if a fracture is suspected because a nondisplaced injury could potentially become displaced or open.


b. Fractures can be splinted in the position in which they are found, but if vascular compromise exists, reduction of dislocations and fractures should be performed on the field with gentle traction, and the extremity should be splinted in the position providing best vascular flow.


c. Open fractures should be suspected when a laceration is seen overlying the deformity.


d. Open fractures should be covered with moist, sterile dressings and splinted. These injuries require emergent care, including intravenous antibiotics and irrigation and debridement in the operating room.


4. Dislocations


a. Dislocations can be reduced by experienced personnel on the field; however, the athlete should always be referred for imaging to assess for fractures.


b. A thorough neurovascular examination is imperative prior to and after the reduction.


c. Knee dislocations in athletes are rare; however, they should be suspected in the injured knee with multidirectional instability.


d. Many will spontaneously reduce prior to evaluation, requiring a high index of suspicion.


e. Early on-field reduction with axial traction is imperative.


f. Rapid transport to a medical facility for orthopaedic and vascular consultation, including vascular studies, is mandatory.


E. Thorax injuries


1. Pneumothorax


a. May be spontaneous or traumatic. Spontaneous pneumothorax occurs more often in sports involving intrathoracic pressure changes (weight lifting and scuba diving).


b. Symptoms of pneumothorax include chest pain, shortness of breath, and diminished breath sounds on auscultation.


c. Field treatment includes transportation to the emergency room in a position of comfort with supplemental oxygen.


2. Tension pneumothorax


a. Can develop as progressive accumulation of air remains trapped within the pleural space


b. This can lead to increased intrathoracic pressure, resulting in decreased ability to ventilate, and can limit cardiac output.


c. Patients may present as hypotensive and hypoxic, with tracheal deviation and venous jugular distention.


d. Unrecognized tension pneumothorax can lead to cardiopulmonary arrest.


e. Immediate needle decompression should be performed using a 14-gauge angiocatheter placed anteriorly along the midclavicular line in the second intercostal space.


f. Patients require rapid transport to a medical facility for definitive thoracostomy tube placement.


3. Cardiac contusion


a. Can result after blunt anterior chest trauma


b. The right ventricle is most often affected because of its anterior position.


c. Patients present with persistent chest pain and tachycardia.


d. Suspected patients should be referred for electrocardiogram (ECG) and telemetry monitoring, as arrhythmias are common.


F. Abdominal injuries


1. Abdominal and pelvic injuries


a. Typically result from blunt trauma, most commonly affecting the liver and spleen


b. These patients may have abdominal pain and potentially referred pain to the shoulder (Kehr sign).


2. Injuries to the kidney


a. May occur with flank or posterior trauma


b. Hematuria may or may not be present, but its absence does not exclude injury.


c. Abdominal pain may not be present because the kidneys are located in the retroperitoneum.


d. A high index of suspicion based on mechanism may be required for the diagnosis.


3. Bowel and pancreatic injuries


a. Can occur with blunt trauma compressing the organs against the vertebral column


b. Presentation may be delayed and often missed initially on CT scan.


c. Laboratory tests and/or serial abdominal examinations may be necessary for diagnosis.


4. On-field examination


a. A single on-field examination is inadequate to exclude injury.


b. Athletes with a concerning mechanism, persistent or worsening pain, rebound tenderness, or abnormal vital signs should be sent for CT scan and/or continued observation.

III. Medical Conditions in Sports

A. Sudden death


1. Hypertrophic cardiomyopathy


a. HCM is the most common cause of cardiac sudden death in athletes.


b. It is characterized by nondilated left ventricular hypertrophy, causing obstruction of the left ventricular outflow tract.


c. Often asymptomatic, it should be considered in athletes with dyspnea on exertion, chest pain, a family history of sudden cardiac death, or with a systolic murmur that becomes louder upon standing.


d. Death from HCM is believed to be due to fatal arrhythmias.


e. Diagnosis can be made with echocardiography.


f. Current recommendations are that athletes with HCM should be excluded from most competitive sports, with few exceptions.


2. Coronary artery abnormality (CAA)


a. The second most common cause of sudden cardiac death is CAA.


b. The most frequent CAA is an anomalous origin of the left main coronary artery; this origin allows for the artery to be compressed under increased cardiac pressure, which restricts circulation to that artery and causes subsequent ischemia to the heart.


c. Occasionally the athlete may experience chest pain, palpitations, or syncope that is related to exercise, but most often CAAs are asymptomatic with a normal physical examination.


d. Diagnosis is by coronary angiography or MR angiography.


3. Long QT syndrome


a. Long QT syndrome is a congenital or acquired repolarization abnormality that can lead to sudden cardiac death via the development of ventricular tachycardia and torsades de pointes (a cardiac arrhythmia).


b. Athletes may be asymptomatic but may have syncope or near-syncope with exercise.


c. If exercise symptoms exist or there is a family history of sudden cardiac death, one should consider an ECG to evaluate for long QT syndrome.


d. Diagnosis is based on the correct QT interval, but there is still controversy as to the interval duration that is considered worrisome.


e. Sports participation is determined by phenotype, genotype, and the presence of a pacemaker.


4. Commotio cordis


a. Commotio cordis is caused by a blow to the anterior wall of the chest, near the heart, with objects such as a hockey puck, baseball, or a karate kick, which can lead to fatal ventricular fibrillation.


b. Most episodes occur in children and adolescents.


c. Survival rates are often low unless prompt CPR and, more important, early defibrillation, can be initiated.


d. Attempts to prevent commotio cordis with chest protectors have not yielded a decline in commotio cordis; however, softer "safety" baseballs may potentially lower the risk.


B. Top five dermatologic conditions


1. Tinea infections


a. Tinea infections are superficial fungal infections caused by dermatophytes.


b. Location on the body determines the naming of the lesion, such as tinea capitis (head), corporis (body), cruris (groin), and pedis (foot).


c. Direct close contact with dermatophytes, coupled with breaks in the skin, can lead to infection.


d. Diagnosis can be confirmed by scraping the scaly edge of lesions and using microscopic examination with potassium hydroxide preparation, looking for characteristic hyphae.


e. Tinea corporis is also referred to as ringworm.


f. Tinea cruris, pedis, and corporis are often treated with topical antifungals, with systemic antifungals reserved for more severe cases, while tinea capitis is treated with systemic antifungals.


g. Tinea corporis is common in wrestlers and must be screened for prior to competition.


h. Treatment is generally needed for 48 hours prior to return to competition.


2. Methicillin-resistant Staphylococcus aureus (MRSA)


a. Community-acquired MRSA is an emerging problem in sports.


b. MRSA often produces painful boils, pimples, or "spider-bite" type lesions.


c. Initial treatment can be with topical mupirocin for small lesions.


d. Larger lesions often require incision and drainage, with trimethoprim/sulfa as the usual first-line oral antibiotic agent.


e. More severe infections may require hospitalization, surgical debridement, and intravenous antibiotics.


f. Prevention can be accomplished by avoiding sharing of personal items (razors, towels, and soaps), good hygiene, and protecting compromised skin.


3. Herpes gladiatorum


a. Herpes gladiatorum is caused by herpes-simplex type 1 virus and is transmitted by direct skin-to-skin contact.


b. Infection occurs in 2.6% to 7.6% of wrestlers and affects primarily the head, neck, and shoulders.


c. Treatment is with oral acyclovir or valacyclovir.


d. Lesions close to the eye can progress to the more serious herpetic conjunctivitis.


e. Return to play is often allowed once lesions have scabbed and crusted over.


4. Acne mechanica/folliculitis


a. Acne mechanica is a type of acne seen in athletes that is caused by friction, heat, pressure, and occlusion of the skin.


b. It is frequently seen in sports requiring protective pads (eg, shoulder pads), including lacrosse, hockey, and football.


c. Lesions appear as red papules in area of occlusion.


d. Treatment is often more difficult than for traditional acne.


e. Washing immediately after exercise can be beneficial, as well as wearing moisture-wicking clothing.


f. Pharmacologic treatment can be with keratinolytics such as tretinoin, but most cases will resolve once the season is over.


5. Subungual hemorrhage


a. Subungual hemorrhages are common in sports. They result from acute trauma, such as having a toe stepped on, or from repetitive trauma, such as a toe being forced continually into the toe box of a shoe.


b. Acutely these hemorrhages can be quite painful. Treatment can consist of evacuating the hematoma by creating a hole in the nail with an electrocautery device or a heated, sterile 18-gauge needle.


c. Chronic hemorrhages can lead to nail dystrophy.


C. Exercise-induced bronchospasm


1. Definition—Exercise-induced bronchospasm (EIB) occurs during or after exercise and is characterized by coughing, shortness of breath, wheezing, and chest tightness.


2. Factors/conditions contributing to EIB


a. Exercise in cold weather


b. Exercise during viral respiratory illnesses


c. Polluted air environment (including in indoor skating rinks from ice-resurfacing machines, or heavily chlorinated pools)


d. Exercise during allergy seasons


e. Intense exercise


3. Diagnosis


a. Diagnosis often can be suspected from the patient's history and physical examination.


b. Office spirometry can be helpful in diagnosing underlying asthma, especially with an FEV1 (forced expiratory volume) of <90%.


c. Exercise challenge testing while observing the patient's symptoms and the patient's response to exercising in his or her own sport can be helpful.


d. The International Olympic Committee recommends the eucapnic voluntary hyperventilation test, which is both sensitive and specific for EIB.


e. Testing with a mannitol inhalation challenge is a newer and potentially more sensitive method than the traditional methacholine inhalation challenge used for asthma diagnosis.


4. Treatment


a. Avoidance of environmental and exercise triggers can be effective but often impractical.


b. Adequate warm-up can help reduce symptoms.


c. Pharmacologic treatment often begins with beta-2 receptor agonists, such as inhaled albuterol, prior to exercise.


d. Oral leukotriene modifiers are also effective in controlling symptoms of EIB.


e. For persistent symptoms, the addition of inhaled corticosteroids can be beneficial.


D. Heat illness


1. Heat cramps


a. Heat cramps are characterized by painful muscle cramping, most commonly seen in the calves, thighs, shoulders, and abdomen.


b. Cramps may occur as a result of a mild dilutional hyponatremia from excessive water intake or significant salt loss through sweating.


c. Treatment is through rest, cooling, intravenous fluids, or oral rehydration, and replacing salt losses.


d. Prevention can be through use of electrolyte sport drinks and potentially through adding some salt consumption during exercise.


2. Heat exhaustion


a. Heat exhaustion is the most common form of heat illness.


b. Findings can include significant fatigue, profuse sweating, core temperatures <40.5° C, headache, nausea, vomiting, heat cramps, hypotension, tachycardia, and syncope.


c. Treatment is by removal from the heat, oral or intravenous rehydration, and rapid cooling.


3. Heat stroke


a. Heat stroke is the most severe of the heat illnesses.


b. Findings in heat stroke are lack of sweating, core temperatures >40.5° C, and mental status changes.


c. Heat stroke is a medical emergency, and rapid whole-body cooling is a necessity.


d. The most rapid cooling can be achieved by whole-body immersion in an ice bath.


e. Basic life support and ACLS protocols must be followed.


f. Failure to recognize and treat heat stroke can lead to end-organ failure and death.


4. Heat syncope


a. Heat syncope can occur with a rapid rise from a prolonged seated or lying position in the heat, resulting in orthostatic syncope from inadequate cardiac output and hypotension.


b. Treatment of heat syncope is accomplished by laying the athlete supine with legs elevated and replacement of any fluid deficits from dehydration.


E. Cold exposure


1. Hypothermia


a. Hypothermia is defined as core body temperature <35° C (95° F), with milder being >32° C and moderate to severe <32° C.


b. Athletes with prolonged exposure to the cold, such as cross-country skiers, are more likely to be affected.


c. Mild hypothermia treatment is through removal from the cold exposure into a warmer environment, removal of wet clothing and replacing with dry clothes, drinking hot liquids, use of warmed blankets, and use of rewarming devices.


d. Moderate to severe hypothermia should be cared for in a controlled medical environment because organ dysfunction and electrolyte imbalances can lead to more serious issues if rewarming is undertaken improperly.


2. Frostbite


a. Frostbite is a localized freezing of tissues and can occur in any exposed body part, most commonly the extremities.


b. Superficial frostbite is a milder form of the condition and is characterized by a burning sensation in the affected area that can progress to numbness. Treatment can be initiated as soon as possible by thawing.


c. Deep frostbite is a more significant problem that is quite painful initially and then also goes numb. Thawing and treatment of deeper affected areas should be done in a hospital or emergency room setting.


3. Prevention of cold illness—Preventing cold exposure-related problems can be achieved by increasing the body's heat production (through eating and increasing muscle activity), proper use of clothing through layering and using wind barriers, and considering avoiding outdoor activities in extreme cold conditions.

IV. Ergogenic Aids

A. Legal


1. Creatine


a. Creatine is one of the most popular nutritional supplements derived from the amino acids glycine, arginine, and methionine.


b. Most creatine is stored in muscle and in its phosphorylated form contributes to the resyn-thesis of adenosine triphosphate.


c. Several studies have been conducted for anaerobic activities and have produced conflicting results on the beneficial effects of creatine on sports performance.


d. No study has shown an improvement in on-the-field performance.


e. Short-term side effects reported include cramping, dehydration, and possible renal effects.


f. Long-term effects of creatine are unknown.


2. Caffeine


a. Consumed daily by athletes and nonathletes alike throughout the world, caffeine can be used to enhance athletic performance.


b. Doses as low as 2 to 3 mg/kg have been documented to improve performance.


c. Caffeine is banned by the International Olympic Committee, but doses of up to 9 mg/kg are necessary to achieve the maximum allowable doses.


d. Caffeine is thought to improve performance by reducing fatigue and increasing alertness.


e. Athletes must exercise caution in using caffeine because daily dietary intake plus the lack of regulation of supplements can potentially lead to an unexpected positive test.


3. Amino acids


B. Illegal


1. Anabolic steroids


a. Anabolic steroids are believed to be widely abused in athletes of all ages, with use reported in up to 10% of adolescent athletes.


b. Steroids are synthetically derived to have similar effects to natural testosterone and can be given orally or through an injection.


c. Side effects include development of atherosclerotic disease, decreased high-density lipoprotein cholesterol, aggression and mood disturbances, testicular atrophy, masculinization in females, gynecomastia in males, acne, and an increased risk for hepatitis and human immunodeficiency virus infections in those sharing needles to inject steroids.


d. Most side effects are believed to be reversible with cessation of use but may require a prolonged period to return to normal.


e. Anabolic steroids are banned by college, Olympic, and most professional teams.


f. Most of these same organizations test for anabolic steroids, looking for a testosterone to epitestosterone ratio greater than 6:1.


2. Erythropoietin


a. Erythropoietin (EPO) acts to stimulate hemoglobin production, which in turn increases the body's oxygen-carrying capacity.


b. This ability has made EPO widely desirable among elite endurance athletes such as cyclists and cross-country skiers.


c. Several studies have documented increases in hematocrit and VO2max in time to exhaustion.


d. Side effects of EPO use include increasing blood viscosity, which can lead to stroke, thromboembolic events, and myocardial infarctions.


e. EPO is currently illegal in all sports.


f. Testing does exist, but the substance can still be difficult to detect.


3. Human growth hormone


a. Human growth hormone (HGH) is a peptide secreted by the anterior pituitary and acts to stimulate the release of insulinlike growth factors.


b. Studies on athletes are essentially nonexistent.


c. Those studies that have been conducted are in patients with endocrine dysfunction and demonstrate increases in muscle size but not in strength.


d. Resistance to continued use is also thought to occur.


e. Side effects include water retention, development of myopathic muscles, carpal tunnel syndrome, and insulin resistance.


f. There are currently no available accurate tests for HGH.


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Top Testing Facts

1. The preparticipation physical examination (PPE) may be normal in athletes with an underlying condition that places them at risk during athletics. A detailed family history and past history of exertional symptoms may provide the only clues to a potentially lethal disorder.


2. Cardiac murmurs that worsen with standing or the Valsalva maneuver, any diastolic murmur, and systolic murmurs greater than 3/6 in intensity should be evaluated further before clearance to play.


3. A cervical spine injury should be assumed in any unconscious athlete.


4. Face masks should be removed to allow access to the airway in an unstable patient; however, the helmet and shoulder pads should be left in place during transport.


5. Experts agree that all symptomatic players with a concussion should be withheld from activity and return-to-play decisions should be individually based.


6. Knee dislocations in athletes are rare; however, they should be suspected in the injured knee with multidirectional instability. A vascular study should be performed if this injury is suspected.


7. A single abdominal examination is inadequate to exclude injury. Athletes with a concerning mechanism, persistent or worsening pain, rebound tenderness, or abnormal vital signs should be sent for CT scan and/or continued observation.


8. Hypertrophic cardiomyopathy is the most common cause of sudden cardiac death in athletes.


9. Heat stroke is a medical emergency and treatment must be initiated promptly.


10. Exercise-induced bronchospasm is frequently managed by limited environmental aggravators and use of beta-2 agonists, such as albuterol, prior to exercise.