Comparison of Preseason and Postseason ImPACT Scores in NCAA

College Soccer Players

Demetri Menegos, D.O. April 16, 2010 Sports Medicine Fellow Atlantic Health--Overlook Mount Sinai School of Medicine

Background

College Soccer players suffer repetitive impact to the head throughout their season through heading of a soccer ball

Both in practice and in games they must strike the ball with their head from defensive and offensive positions

This exposes them to multiple impacts to the head throughout their season

Depending on position some players will head the ball more than others

Background

How repetitive heading of a ball throughout a season may affect a player's performance on Neuropsychological testing is unclear

There is much ongoing debate as to the effect of heading a ball on a soccer player's long term health

It has been suggested that soccer players should wear protective head gear, especially at the youth level to protect a player from developing Neurocognitive dysfunction secondary to heading

Headgear in Soccer

Mainly marketed to Youth Soccer players under the age of 12, where the occurrence of heading is significantly decreased, as compared to higher levels of play

Many of the headers at this level occur off the bounce

Studies have shown that the peak force of impact from a soccer ball was reduced by 112% or 400 N

Clinical Efficacy remains to be seen

Specifications of the Ball

Law 2 of the game, as per FIFA's Laws of the Game, states :

Circumference : 27-28 in. (68-70 cm) Weight : 14-16 oz. (410-450 grams) Pressure : 8.5-15.6 psi (59-108 kPa)

Mechanics of Impact

The highest velocity balls a player might head voluntarily are as follows :

Goalkeeper's Punt : 70km/h or 43 mph Goalkeeper's Dropkick : 85 km/h or 53 mph Goal Kick : 85 km/h or 53 mph Shot towards goal from a striking position : 119

km/h or 74 mph

Mechanics of Impact

A ball traveling at between 65 km/h and 120 km/h :

Hits a solid object for 10.23 milliseconds Force of 850N to 1200 N Acceleration of 30 to 55 g forces

Mechanics of Impact

Head can withstand greater linear forces than those created by properly heading a soccer ball

Purposeful heading is largely linear Most head injury occurs from rotational forces,

as in boxing A blow of the ball to the side of the head in an

unprepared player, or via improper or bad heading technique, can lead to rotational impact

Can be coupled with Transverse Rotation in an unprepared player

Mechanics of Impact : In Comparison

Football : Impacts last for 250 to 300 milliseconds at g forces ranging from 150 to 450 g

Boxing : Impact duration lasts from 14 to 18 milliseconds

6000 N G forces of 100 g

Mechanics of Heading

Heading the ball appropriately is a difficult technique and certainly tough to master as an effective threat at the college or professional level

Most coaching books that describe teaching progression don't even mention heading until 12 years of age or older

Active technique Ball is to be contacted on the forehead at or

near the hairline

Mechanics of Heading

The trunk is hyperextended and the chin tucked in slightly to the chest

The more trunk extension, the faster the forward velocity of the trunk and the greater the impact on the ball

Arms are usually extended for balance and protection

Exercise in precision timing

Mechanics of Heading

Flexing the hips, brings the trunk and head towards the ball

Arms are pulled back Contracting the neck muscles fixes the head,

making a firm surface for contact Effectively increasing the mass of the contact

surface, F=ma To contact the ball at the top of a jump, the

trunk must be flexed to transfer force to the ball

Mechanics of Heading

Proper heading technique is the athlete's best defense against injury from heading a soccer ball

Younger athlete may be at risk because of smaller size, less muscular development and less skillful heading technique

Mechanics of Heading

Coaches should instruct players to head the ball just below the hairline on the frontal bone

The thickest part of the cranium Simultaneously isometrically contracting the

neck musculature To counteract the force of the ball, the player

should apply a counterforce, generated by moving the trunk into flexion

Mechanics of Heading

The athlete becomes a single rigid unit that lowers the risk of injury, by decreasing the linear and rotational accelerations on the head

Forces generated by the ball are dispersed across the player's body

Mechanics of Heading

Frequency of Heading

Not a lot of data to document the frequency of heading

The average amount of headers per game in the English Premier League is stated to be six to seven per game

Incidence of Concussion in Soccer

According to a study of concussions in soccer players by Dick, Putukian, Agel, Evans, and Marshall (2007)

67.7% of reported concussions were due to player contact

18.3% were associated with contacting the ball 13.4% with contacting the playing surface

Incidence of Concussion in Soccer

In a Canadian study on concussions in University Football and Soccer players by Delaney, Lacroix, Leclerc and Johnston (2002)

70.4% of Football players had suffered concussion symptoms within the previous year

62.7% of Soccer players had suffered concussion symptoms

23.4% of Football players and 19.8% of concussed soccer players realized they had suffered a concussion

Incidence of Concussion in Soccer

Goalkeepers were the most commonly affected position

Concerns : Soccer and Head Injury

Head injuries account for 4 to 20% of all injuries in soccer

In a study involving US National Team players, the findings suggested that any evidence of encephalopathy in soccer players relates more to acute head injuries received playing soccer than from repetitive heading (Jordan, 1996)

In an Italian retrospective study involving professional players from the top three Italian divisions, there was a 20-fold increased incidence of ALS as compared to the general population (Vanacore and Belli, 2005)

Hypothesis

No difference exists between Preseason and Postseason Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) scores when NCAA College Soccer players sustain subconcussive microtrauma from forceful, repetitive contact activity through heading a ball from defensive and offensive positions

Purpose

The purpose of this study is to evaluate the effect of heading on performance in Neuropsychological testing

To this effect Preseason and Postseason ImPACT testing would be used to evaluate for Neuropsychological dysfunction in NCAA Division III US College Soccer players

Methods

Men's Soccer players from a large Division III University were recruited to participate in the study

Athletes were ImPACT tested at the beginning of their NCAA Division III Soccer season

They were ImPACT tested again at the very end of their NCAA Division III Soccer Season

The season had a length of twenty games The regular season lasted for two months

Methods

Players suffering a concussion at any point during the season were excluded from the study

13 Soccer players completed Preseason and Postseason ImPACT testing without having suffered a Concussion during the season

Four players suffered a concussion over the course of the season

Five players didn't complete the Postseason ImPACT

Methods

A Statistician was employed as part of the study to run the study data

A repeated measures analysis of variance was used to compare the scores at the two time intervals

Preseason and Postseason ImPACT scores were evaluated for statistical significance

Results

No statistically significant decreases were found in overall ImPACT scores when comparison was made between Preseason and Postseason ImPACT scores

Symptom scores, Visual and Verbal Memory Composite Scores were compared for statistical significance

No significant decrease was noted between Preseason and Postseason scores (p<0.05)

Results

There was no significant decrease in Visual or Verbal Memory Composite scores (p<0.05)

P values were calculated to be : Visual Memory Composite : p=0.01 Verbal Memory Composite : p=0.04

Results

Total Symptom Score remained stable between Preseason and Postseason (p<0.05)

Total Symptom Score : p=0.04 Reaction Time Composite scores showed a

wide spectrum of scores with a p=0.389

Discussion

Total Symptom Scores, Memory Composite Verbal Scores and Memory Composite Visual Scores on ImPACT testing were unchanged (p<0.05) between Preseason and Postseason

These findings fall in line with a College Football study evaluating ImPACT scores in athletes at similar intervals by Adamson, Pink and Sweet, 2007

ImPACT scores were not significantly altered in non-concussed football players

Discussion

No statistically significant decreases were found in overall ImPACT scores in any of the domains or composites of the tests

Conclusions

ImPACT scores are not significantly altered by a season of repetitive microtrauma due to heading of a soccer ball in collegiate athletes who did not sustain a concussion

Conclusion

This is a small scale Pilot study evaluating the effects of repetitive subconcussive microtrauma due to heading of a ball in NCAA College Soccer players on Neuropsychological ImPACT testing

The study should be performed on a larger scale to evaluate the effects of heading on an athlete's Neurocognitive functioning

This includes a larger sample size in terms of participating athletes

Conclusion

More Importantly : It must be considered that the NCAA College

Soccer season in the respective study had a duration of two months and twenty official competitive matches

Conclusion

The College Soccer season is significantly shorter than the International Soccer Season

The Professional Soccer Season in the majority of professional leagues around the world can last up to eleven months when including Preseason and Postseason matches

Professional Soccer players may play upwards of 75 matches a year when Club and International commitments are taken into account

Conclusion

It would be prudent to extrapolate the study on a professional level

Testing professional soccer players via ImPACT testing Preseason, Midseason and Postseason

Ideally, Soccer players would be ImPACT tested at the beginning of the traditional Preseason at the beginning of July, Midseason and at the end of the traditional season at the end of May

Clinical Significance

ImPACT scores should be correlated with clinical findings to evaluate an athlete for the occurrence of a Post-concussive event

Bibliography

Jordan BD. Acute and chronic brain injury in United States national team soccer players. Am J Sports Med 1996;24:704-5.

Belli S, Vanacore N. Proportionate mortality of Italian soccer players: Is Amyotrophic Lateral Sclerosis an occupational disease. European Journal of Epidemiology 2005;20,3:237-242.

Dick, R., Putukian, M., Agel, J., Evans, T. A., & Marshall, S. W. (2007). Descriptive epidemiology of collegiate women’s soccer injuries: National Collegiate Athletic Association Injury Surveillance System, 1988–1989 through 2002–2003. Journal of Athletic Training, 42(2), 278–285.

Broglio, S. P., Ju, Y., Broglio, M. D., & Sell, T. C. (2003). The efficacy of soccer headgear. Journal of Athletic Training, 38(3), 220–224.

Bibliography

Kirkendall, D. T., & Garrett, E., Jr. (2001). Heading in soccer: Integral skill or grounds for cognitive dysfunction? Journal of Athletic Training, 36(3), 328–333.

Delaney JS, Lacroix VJ, Leclerc S, Johnston KM (2002). Concussions among university football and soccer players. Clin J Sport Med. 2002 Nov;12(6):331-8.

Putukian M, Echemendia R, Mackin S. The acute neuropsychological effects of heading in soccer. Clin J Sports Med 2000;10:104-9.

Miller JR, Adamson GJ, Pink MM, Sweet JC (2007). Comparison of preseason, midseason, and postseason neurocognitive scores in uninjured collegiate football players. Am J Sports Med. 2007 Aug;35(8):1284-8.

Thank You!

Michele Gilsenan, D.O. Peter Barry, D.O. Michael Beams, D.O. Nick Belasco, D.O Tim Sensor, ATC Kean University Soccer