Children's Doctor

Sports Medicine - Spring 2011

Feeling Foggy

Matthew Grady, MD [email]

A 16-year-old male soccer goalie presents to the sports medicine clinic for evaluation of an injury sustained 2 weeks ago. During a soccer game he was struck in the face by the soccer ball after a shot from a short distance. Later in the game, he again was hit in the face by another short-range shot. He continued to play and does not remember the rest of the game. Afterward, he was taken to the local ED, where a CT scan was negative.

During the past 2 weeks his symptoms have been unchanged. He has missed only 2 days of school, but his school performance in college-prep classes is poor. Current symptoms include headache, nausea, balance problems, dizziness, fatigue, trouble falling asleep, drowsiness, sensitivity to light, sensitivity to noise, irritability, sadness, and nervousness; feeling more emotional, slowed down, and mentally foggy; difficulty concentrating and remembering, and visual problems.

Medical history includes a concussion sustained more than 1 year ago. He is a good student with no history of migraine headaches, ADD, learning disorders, or mood disorders.

Physical exam is notable for the inability to track a fast-moving object, and an abnormal gait with heel-to-toe walking forward, backward, and backward with eyes closed.

Computerized neuropsychological testing demonstrates scores below the first percentile.

Discussion: The Third International Conference on Concussion in Sport (Zurich) defines concussion’s 5 major features:

  1. Concussion may be caused either by a direct blow to the head, face, or neck, or elsewhere on the body with an impulsive force transmitted to the head.
  2. Concussion typically results in the rapid onset of short-lived impairment of neurologic function that resolves spontaneously.
  3. Acute clinical symptoms largely reflect a functional disturbance rather than a structural injury.
  4. Concussion results in a graded set of clinical symptoms that may or may not involve loss of consciousness (only about 10% of cases involve LOC).
  5. No abnormality on standard structural neuroimaging studies is seen in concussion.

The diagnosis of concussion remains a clinical decision. Some individuals may exhibit signs or symptoms immediately, but it is common for concussion symptoms to develop over a 6-24 hour period after the initial injury. Office evaluation of concussion should focus on the mechanism of injury, current symptoms, and deficits of function.  Physical exam should specifically target 3 common areas of deficits: visual tracking, balance, and cognitive function. History taking should recognize that symptoms will become worse with either physical or cognitive exertion (schoolwork) during the acute phase of a concussion. (See Table 2)

The recent increase in concussion research and a better understanding of the pathophysiology have changed concussion management. Over the past 15 years, the lateral fluid percussion animal model has been developed, providing insight on the pathophysiological processes that occur at the cellular level after a concussion. The concussion injury is now viewed as a 2-part process: a primary insult and a secondary inflammatory response.

Table 1: Concussion Symptoms
(adapted from AAP concussion statement)


  • Headache
  • Nausea
  • Vomiting
  • Balance problems
  • Visual problems
  • Fatigue
  • Sensitivity to light
  • Sensitivity to noise


  • Feeling mentally "foggy"
  • Feeling slowed down
  • Difficulty concentrating
  • Difficulty remembering
  • Feeling confused/disoriented
  • Amnesia


  • Irritability
  • Sadness
  • Feeling more emotional
  • Nervousness


  • Drowsiness
  • Sleeping more than usual
  • Sleeping less than usual
  • Difficulty falling asleep

The primary injury occurs as the result of acceleration and deceleration forces to the nerve cell membrane and brain axons. The initial insult results in a pathologic release of excitatory amino acid neurotransmitters (glutamine and aspartate) that lead to loss of cell-wall integrity. Subsequent changes in the permeability of the cell wall allow an influx of sodium and an efflux of potassium. The changes in intracellular sodium and potassium alter the pH of the cell, leading to an influx of calcium. Further disruption in concentrations of intracellular ions and pH results in cellular damage. Until the intracellular environment is restored, these cells and axons do not function properly.

Table 2: Physical Exam Deficits

Visual Tracking

Inability to track alternating fast-moving
horizontal objects/instability of visual gaze
(nystagmus), jerkiness of pursuits (eye tracking), or jerkiness of saccades (visual scanning).

Formal testing: King-Devick testing will be available in the near future.


Truncal instability when tandem walking heel to toe, graded by degree of difficulty (forward, backward, backward with eyes closed)

Formal testing: Bess testing model


Inability to recall words or number sequences, or to do simple tasks like recite months in reverse

Formal testing: SCAT 2 or computerized testing

As severely injured cells die, they release cytokines that upregulate the inflammatory process, prompting secondary injury. This cascade of cell injury may explain why concussive symptoms can worsen clinically over the first 6-24 hours after the initial injury.

To restore the intracellular balance, mild and moderately injured cells can upregulate Na/K ATPase-dependent ion membrane transport proteins. These Na/K pumps are fueled by glucose. Immediately after an injury, there is a huge increase in glucose demand by the brain. Glucose delivery by cerebral circulation after a brain injury is thus crucial to restoration of intracellular ion balance and cell membrane healing.

However, during the acute injury, the brain temporarily loses the ability to regulate cerebral blood flow (and glucose delivery) to match metabolic demand. This creates a situation, called the metabolic mismatch phase, where the metabolic demands exceed the delivery of nutrients including glucose.

Current treatment of concussion involves limiting the metabolic demands on the brain during this recovery phase. The concept of complete cognitive rest (no schoolwork, video games, text messaging, interactive computer use, or other brain-intensive activities) is important early in the injury. As symptoms resolve, these activities are gradually reintroduced.

Physical activity is curtailed until the patient is symptom-free at rest. Physical activity is reintroduced gradually: Athletes progress in steps from mild, to moderate, to heavy aerobic exertion as long as they remain asymptomatic. Full play is restricted until the student has a normal physical exam, normal cognitive function, and no symptoms with both physical and cognitive stress

Healing times vary with injury severity but in general, the younger the individual, the longer the recovery time. Middle school students frequently take 2-4 weeks to completely recover, high school students generally take about 10-14 days. Adults often heal within a week.

The soccer goalie (who did not get any rest during the critical 2-week period immediately after his concussion) was sent home for complete cognitive rest for 2 weeks. His symptoms improved and he attempted the transition back to school. He did not get sufficient cognitive rest and his symptoms worsened. He was placed on homebound education for a month and then slowly reintegrated into school. Complete recovery took about 4 months. On final physical exam, his balance and eye tracking were normal. His computerized neurocognitive tests demonstrated scores in the normal range and his school function was back to normal.

References and Suggested Readings
Halstead ME, Walter KD; Council on Sports Medicine and Fitness. American Academy of Pediatrics. Clinical report: Sport-related concussion in children and adolescents. Pediatrics 2010; Sep;126(3):597-615.   

Exercise Guide for Children and Adolescents

Arlene M. Goodman, MD [email]

YM is a 15-year-old healthy female who presents with right shin pain that began 1 month after starting cross country. The pain was on the medial side of her shin with activity only; however, in the past 2 weeks it has progressively worsened and she has pain with walking. She denies any acute injury. Her pain worsens with running, jumping, and prolonged walking. It is improved by non-weight-bearing. She reports adequate caloric and calcium intake. She has normal menses. She did not run over the summer. She began running 4 miles per day with her cross country team 6 days per week, and 3 miles on her day off. She has no significant medical history.

On physical exam she is 5’1” and 105 pounds. She has a BMI of 19.6 (37 percentile). She pronates and has an antalgic gait with decreased stance time. She has pain walking on her heels and toes, as well as hopping on her right foot. She has focal tenderness on the posteromedial tibia at the junction between the middle and distal thirds. She has normal ROM and strength in her ankle and knee. She has no leg length discrepancy.

Discussion: YM has a tibia stress fracture, and her injury could have been prevented by sound training principles. An athlete should not increase the number of repetitions, total weekly distance, or total weekly training time by more than 10% per week. Therefore, athletes should begin a preseason conditioning program 4-6 weeks before the season begins. The program should include stretching exercises, resistance training, and aerobic activity. 

YM is also at risk for overtraining. Common symptoms include increased resting heart rate, decreased enjoyment of usually fun activities, decreased appetite, depressed mood, lack of motivation, fatigue, decreased academic performance, and nonspecific pain. To prevent this, athletes should be encouraged to participate in more than 1 sport. They should take 1 to 2 days off per week from organized physical activity and 2 to 3 months off per year from their specific sport. During this time, they can cross train or participate in other sports. The American Academy of Pediatrics Committee on Sports Medicine and Fitness discourages specialization in a single sport before adolescence. Athletes who participate in a variety of sports before puberty play sports longer and have fewer injuries if the various sports emphasize different body parts.


On one hand, there is an epidemic of overuse injuries, and on the other hand, there is an epidemic of childhood obesity. The American Academy of Pediatrics recommends children and adolescents get at least 60 minutes per day of moderate to vigorous physical activity. This may be done in small increments. Moderate activity increases the heart rate to between 50% and 70% of the maximum heart rate. This is estimated by 220 minus age in years. The individual should be able to hold a conversation. Examples are walking at 3.5 mph, bicycling at <10 mph, hiking, dancing, or light strength training. Strength training can begin when the child or adolescent has the emotional maturity to follow directions. There must be good supervision and teaching of proper techniques, and training should emphasize low weight and high repetitions.

Age-Appropriate Recommendations for Physical Activity
Age Recommendations Activities

4 – 6 years

  • Encourage free play
  • Emphasis on fun, experimentation, and exploration
  • Instruction limited to a show-and-tell format
Running, swimming, tumbling, skipping, throwing and catching

6 – 9 years

  • Encourage free play
  • Emphasis should be on developing fundamental skills and not on competition
  • May participate in organized sports but they should have flexible rules, short instruction time and allow free time at practices
Walking, dance, jump rope, gymnastics, martial arts; organized sports (soccer, baseball, tennis)

10 – 12 years

  • Emphasis should be on skill development and not on competition
  • May begin to incorporate instruction tactics and strategy
Complex sports (football, basketball, ice hockey) and strength training


  • Emphasis should be on activities that interest the adolescent
Competitive and noncompetitive sports; dance, yoga, running, strength training

Vigorous activity increases the heart rate to more than 70% of its maximum. It makes you breathe hard and sweat, and it is more difficult to maintain a conversation. Examples include walking at 4.5 mph, bicycling at >10 mph, swimming, basketball, running or jogging, and most competitive sports.

Overweight or obese children should gradually increase activity levels and decrease sedentary behavior. These children often enjoy strength training because they are often stronger than their peers, increasing confidence in their ability to be physically active. In all activities, the emphasis should be on fun, safety, and promoting lifelong physical activity.

References and Suggested Readings
Brenner JS and the Council on Sports Medicine and Fitness. Overuse injuries, overtraining, and burnout in child and adolescent athletes. Pediatrics 2007;119:1242-1245

American Academy of Pediatrics, Council on Sports Medicine and Fitness and Council on School Health. Active Healthy Living: Prevention of childhood obesity through increased physical activity. Pediatrics 2006;117:1834-1842.

Knee Trouble

Angela Smith, MD

A 13-year-old female ballet dancer and year-round soccer player comes to the office the first week in January, complaining of bilateral knee pain. The pain began in early December, when she was playing indoor soccer and participating in Nutcracker ballet rehearsals. She points to the entire anterior knee as being painful, the right knee more than the left, with the inferior patella area sometimes painful.

She has little pain during soccer but has pain afterward. During ballet practices, jumping becomes painful, but most of the pain is after practice. The right knee occasionally swells, just mildly puffy. The right knee has buckled but never caused her to fall. She has no true locking but does have pain and a feeling of stiffness when she tries to get up after sitting for a long time. If she stands for a long time in a ballet pose with one knee locked in extension, she has initial difficulty getting that knee moving again. After dance she rates her pain 8 out of 10. She takes 400 mg of ibuprofen in the morning, before ballet, and at bedtime.

She is otherwise healthy. The only other joint problem is occasional right lateral hip pain, and she points just above the greater trochanter. The hip pain occurs only when she runs for a long time for soccer conditioning. She has no unexplained rashes or fevers. Her mother says she grew 3 inches in the last 6 months. Menarche was 2 months ago.

She had a right ankle sprain a year ago that was treated with crutches and non-weight-bearing for 2 weeks; then she was instructed to resume her activities without any physical therapy or recommendations for gradually progressive activity increase. Six months ago she sustained a stress fracture of the right fibula during a summer ballet “intensive.” She stopped soccer and ballet for 2 weeks. At her next physician visit she was pain-free and was told she should only swim for the next 2 weeks and then could gradually resume usual activities as long as she remained pain-free. She did well until knee pain began in December.

On physical examination she is slender but well-developed. Her gait is normal except the “too many toes sign” (when watched from behind) and her kneecaps point toward each other. This rotational malalignment improves a bit when she walks on her tiptoes or heels. When she hops on one foot, the knee of the hopping leg points medially while the foot points laterally. When she does a plié in first position, her feet roll inward (flattening the arch) as she forces the turnout position, and her patellae point medially relative to her toes. She can jump up from a full squat without difficulty.

The right vastus medialis and calf appear smaller than the left, but otherwise her muscles look symmetric. All the lower extremity joints have full, painless range of motion, without swelling or instability. The popliteal angles are 20°, just slightly tighter than normal for a soccer player, but much less than expected for a ballet dancer. Her iliotibial bands at knee level feel taut, and the right is slightly tender. The right patella is subluxated but reducible, with marked lateral tilt. The left patella is not subluxated but has decreased medial glide. Maximal tenderness of both knees is at the anterior aspect of the lateral femoral condyle, where the lateral patella is compressed against it consistently, as it lacks the normal medial glide. This is much worse on the right than on the left. Also, the right patella has mild tenderness over the medial plica and inferior pole of the patella. The skin color, temperature, and sensation are normal.

She is almost at the end of her peak height velocity segment on the growth chart. AP, lateral, tunnel, and tangential patellar views of both knees are unremarkable except patellar tilt on the right.

These findings are most consistent with bilateral patellofemoral pain syndrome, iliotibial band syndrome, right patellar subluxation,  and right jumper’s knee. Despite multiple joint involvement, she has almost no swelling and no systemic symptoms, so inflammatory and infectious diagnoses are unlikely. Her history is typical for patellofemoral pain, and her physical findings confirm the diagnosis.

After 4 weeks of physical therapy, including stretching the tight hamstrings and iliotibial bands, strengthening with emphasis on the quadriceps and hip external rotators, and manual stretching of the right lateral patellar retinaculum, she is pain-free. After 4 more weeks, the muscles of both legs appear symmetric, she hops with normal rotational control, and she can properly control her ballet positions. She initially had to stop all pain-provoking activities and become pain-free so she could benefit from PT. By her 2-month checkup she has gradually resumed all her usual training.

Additional Risk Factors for This Athlete

Pre-teen and adolescent girls (more often than boys) may have the jumping mechanics shown here: The legs make an "A" shape rather than having the knees aligned over the feet on take-offs and landings. When this young figure skater attempts her one-foot landing position, the foot pronates and the knee points inward as the hip internally rotates. Her feet appear relatively strong, but the hip external rotators are not supporting her properly and were found to be weak.
This 14-year-old boy was rehabilitating a left fibular stress fracture. He improved the strength on the injured leg so that he had better angular and rotational control of the injured leg than the uninjured one.

References and Suggested Reading
Smith AD. The skeletally immature knee: what's new in overuse injuries. Instructional Course Lectures: Sports Medicine, Ireland ML ed. American Academy of Orthopaedic Surgeons, 2005.

Referral Information

The Center for Sports Medicine and Performance at CHOP sees patients at the Main Campus in West Philadelphia and at several locations in the CHOP Care Network, and offers extensive services in King of Prussia. Other sports medicine locations include Specialty Care Centers in Chalfont and Exton, Pa, and Voorhees, Princeton, and Atlantic County, NJ.

To refer a patient, please call 215-590-1527 for the Division of Orthopaedic Surgery or 215-590-SPORTS for acute sports injuries at any site, 267-426-9600 for the Cardiac Center, or 215-590-6919 for nutrition counseling, physical therapy, and other sports medicine services at KOP. Direct patients to or for more information.


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