Incidence of Concussions in Elite Female Water Polo: A Retrospective Analysis.

OBJECTIVE: Current evidence for concussions is mixed in water polo players. Surveys suggest rates as high as 36%, whereas surveillance studies at international competitions often fail to report them at all. The goal of this study was to examine the incidence of concussions in elite female water polo players from surveillance tools implemented longitudinally. DESIGN: Retrospective chart analysis of 10 years spanning between 2012 and 2022. SETTING: National teams or professional sports. PARTICIPANTS: Female players from the Canadian senior national water polo teams that participated in international competitions and trained more than 10 hours per week in a competitive environment. ASSESSMENT OF RISK FACTORS: Included player position, recurrence, and time loss before full return to play. MAIN OUTCOME MEASURES: Prevalence of concussion diagnosis. RESULTS: Forty-three concussions were identified over the 10 years observed at a median count of 3 concussions per year. Cumulative days lost spanned between 25 and 348 days per team*year. Altogether, this produced a median rate of 14.3 injuries per 100 player*years. Goalkeepers in the sample suffered the highest rates of concussion (25.8%), compared with players in other positions (22.8% of centers and 16.7% of drivers). CONCLUSIONS: This study found evidence for prevalence of concussions in elite female water polo players. Improved guidelines preceded a significant reduction in time loss after the year 2017. This adds to a body of knowledge suggesting that improved surveillance methods are needed to detect and care for concussions in this population.

The awareness of injury prevention programmes is insufficient among French- and German-speaking sports medicine communities in Europe.

PURPOSE: Evaluate the current state of sports injury prevention perception, knowledge and practice among sports medicine professionals located in Western Europe and involved in injury prevention. METHODS: Members of two different sports medicine organizations (GOTS and ReFORM) were invited to complete a web-based questionnaire (in German and in French, respectively) addressing perception, knowledge and implementation of sports injury prevention through 22 questions. RESULTS: 766 participants from a dozen of countries completed the survey. Among them, 43% were surgeons, 23% sport physicians and 18% physiotherapists working mainly in France (38%), Germany (23%) and Belgium (10%). The sample rated the importance of injury prevention as "high" or "very high" in a majority of cases (91%), but only 54% reported to be aware of specific injury prevention programmes. The French-speaking world was characterized by lower levels of reported knowledge, unfamiliarity with existing prevention programmes and less weekly time spent on prevention as compared to their German-speaking counterparts. Injury prevention barriers reported by the respondents included mainly insufficient expertise, absence of staff support from sports organizations and lack of time. CONCLUSION: There is a lack of awareness regarding injury prevention concepts among sports medicine professionals of the European French- and German-speaking world. This gap varied according to the professional occupation and working country. Relevant future paths for improvement include specific efforts to build awareness around sports injury prevention. LEVEL OF EVIDENCE: Level IV.

Hypertrophic pyloric stenosis in the Maritimes: examining the waves of change over time.

BACKGROUND: Changing patterns of referral and management of pediatric surgical conditions, including hypertrophic pyloric stenosis (HPS), have recently been described and often relate to comfort with early nonoperative management, anesthesia and corrective surgery. Travelling distance required for treatment at pediatric centres can also be burdensome for families. We assessed referral patterns for HPS in the maritime provinces of Canada over 10 years to quantify the burden on families travelling for surgical care. METHODS: We reviewed the charts of all patients with HPS in the Maritimes. Length of hospital stay (LOS) and complication rates were analyzed in regards to resuscitation and management at a pediatric centre and/or peripheral centres. We used postal codes for each patient to track distance travelled for management. RESULTS: We assessed 751 cases of HPS. During the study period (Jan. 1, 2001-Dec. 31, 2010), referral to pediatric centres increased from 49% to 71%. Postoperative complications were 2.5-fold higher in peripheral centres. Infants referred to pediatric centres were 78% less likely to have an LOS longer than 3 days. Laparoscopic pyloromyotomy, which was performed only in pediatric centres, was associated with a shorter postoperative LOS. CONCLUSION: Our study supports the current literature demonstrating improved outcomes, shorter overall LOS and decreased risk of complications when infants with HPS are treated in pediatric centres. This should be considered when planning access to pediatric surgical resources.

CONTEXTE: Une évolution des tendances dans les pratiques d'orientation des patients et de prise en charge des affections pédiatriques nécessitant une intervention chirurgicale, telles que la sténose hypertrophique du pylore (SHP), a récemment été décrite; elle dépend souvent du degré d'acceptation de la prise en charge non chirurgicale précoce, de l'anesthésie et de la chirurgie correctrice. Le traitement en centre pédiatrique peut exiger des déplacements pénibles pour les familles. Nous avons évalué les pratiques d'orientation des cas de SHP dans les provinces maritimes du Canada sur une période de 10 ans pour quantifier l'ampleur du fardeau qui incombe aux familles devant voyager pour obtenir des soins chirurgicaux. MÉTHODES: Nous avons étudié le dossier de tous les patients atteints de SHP dans les Maritimes et avons comparé la durée de séjour et le taux de complications associés à la réanimation et à la prise en charge dans les centres pédiatriques et les centres périphériques. Nous avons aussi utilisé les codes postaux des patients pour déterminer la distance de déplacement des familles. RÉSULTATS: Nous avons analysé 751 cas de SHP. Pendant la période à l'étude (2001­2010), le taux d'orientation des patients vers les centres pédiatriques est passé de 49 % à 71 %. Les complications postopératoires étaient 2,5 fois plus courantes dans les centres périphériques, et les séjours de plus de 3 jours étaient 78 % moins fréquents chez les nourrissons traités en centre pédiatrique. La pyloromyotomie par laparoscopie, réalisée dans les centres pédiatriques seulement, a été associée à une réduction de la durée de séjour postopératoire. CONCLUSION: Notre étude va dans le même sens que la littérature actuelle, qui indique que le traitement des nourrissons atteints de SHP en centre pédiatrique est associé à de meilleurs résultats postchirurgicaux, à une durée d'hospitalisation moins longue et à un risque de complications plus faible que le traitement dans un centre périphérique. Ces résultats devraient être pris en compte dans la planification de l'accès aux ressources dans le domaine de la chirurgie pédiatrique.

Signs of low energy availability in elite male volleyball athletes but no association with risk of bone stress injury and patellar tendinopathy.

Relative Energy Deficiency in Sport (RED-S) syndrome is associated with undesirable health and performance outcomes. The aetiology of RED-S syndrome is low energy availability (LEA). LEA has been reported in male athletes in various sports, but there is little information in team sports. Therefore, the aims of this study were to assess the point-prevalence of surrogate markers of LEA in elite male volleyball players and examine the association between low and normal total-testosterone (TES) on endocrine markers, resting metabolic rate, bone mineral density (BMD), and history of injury/illness. Using a cross-sectional design, 22 elite male volleyball players underwent anthropometric, dual-energy X-ray absorptiometry (DEXA or DXA) and resting metabolic rate testing, bloodwork, dietary analysis, the three-factor eating questionnaire-R18, injury/illness questionnaire and Victorian Institute of Sport Assessment - patellar tendon questionnaire. The primary finding of this investigation was that 36% of athletes had ≥2 surrogate markers of LEA. Although fasted insulin was lower and cortisol was higher in players with low-total TES, low BMD, low RMR and various other endocrine markers linked to LEA were not observed. More research is required to define surrogate markers of LEA in male athletes.HIGHLIGHTS Thirty-six percent of volleyball players had ≥2 surrogate markers of LEA.The Cunningham, 1991 predictive RMR equation and/or the cut-off point (<0.9) may be unsuitable for detecting energy conservation associated with LEA in large male athletes.There was no association between total-TES and risk of bone stress injury, illness and patellar tendinopathy.

Impact of COVID-19 Vaccination on Short-Term Perceived Change in Physical Performance among Elite Athletes: An International Survey.

COVID-19 vaccination raised concerns about its potential effects on physical performance. To assess the impact of COVID-19 vaccination on the perceived change in physical performance, we conducted an online survey among elite athletes from Belgium, Canada, France and Luxembourg, with questions about socio-demographics, COVID-19 vaccination, perceived impact on physical performance and perceived pressure to get vaccinated. Full vaccination was defined as two doses of mRNA or vector vaccine or a heterologous vaccine scheme. Among 1106 eligible athletes contacted, 306 athletes answered the survey and were included in this study. Of these, 72% perceived no change in their physical performance, 4% an improvement and 24% a negative impact following full COVID-19 vaccination. For 82% of the included athletes, the duration of the negative vaccine reactions was ≤3 days. After adjustment for potential confounding variables, practicing an individual sport, a duration of vaccine reactions longer than 3 days, a high level of vaccine reaction and the perceived pressure to get vaccinated were independently associated with a perceived negative impact on physical performance of more than 3 days after the vaccination. The perceived pressure to get vaccinated appears to be a parameter associated with the negative perceived change in the physical performance and deserves further consideration.

Neuropsychological and neurophysiological assessment of sport concussion in children, adolescents and adults.

OBJECTIVE: To determine whether age differences exist with respect to neuropsychological and electrophysiological functioning following a sport concussion. DESIGN: Cross-sectional study. PARTICIPANTS: Ninety-six athletes (9-12 years, n = 32; 13-16 years, n = 34; adults, n = 30), half of whom had a sport concussion. INTERVENTION: Cognitive functioning was assessed using standardized neuropsychological tests and event-related potentials elicited by a visual 3-stimulus oddball paradigm. The PCSS was used to assess symptoms experienced at the time of injury. MAIN OUTCOME MEASUREMENTS: Neuropsychological assessment with an adaptation of the battery used by the National Hockey League. Latencies and amplitudes of the P3a and P3b were analysed in terms of group (concussed vs. control) and age. RESULTS: All concussed athletes had significantly lower amplitude for the P3b component compared to their non-injured teammates (p > 0.05). Adolescents also showed persistent deficits in working memory (p > 0.05). CONCLUSIONS: These data suggest persistent neurophysiological deficits that are present at least 6 months following a concussion. Moreover, adolescents are more sensitive to the consequences of concussions than are children or adults.

Metabolic changes in concussed American football players during the acute and chronic post-injury phases.

BACKGROUND: Despite negative neuroimaging findings many athletes display neurophysiological alterations and post-concussion symptoms that may be attributable to neurometabolic alterations. METHODS: The present study investigated the effects of sports concussion on brain metabolism using 1H-MR Spectroscopy by comparing a group of 10 non-concussed athletes with a group of 10 concussed athletes of the same age (mean: 22.5 years) and education (mean: 16 years) within both the acute and chronic post-injury phases. All athletes were scanned 1-6 days post-concussion and again 6-months later in a 3T Siemens MRI. RESULTS: Concussed athletes demonstrated neurometabolic impairment in prefrontal and motor (M1) cortices in the acute phase where NAA:Cr levels remained depressed relative to controls. There was some recovery observed in the chronic phase where Glu:Cr levels returned to those of control athletes; however, there was a pathological increase of m-I:Cr levels in M1 that was only present in the chronic phase. CONCLUSIONS: These results confirm cortical neurometabolic changes in the acute post-concussion phase as well as recovery and continued metabolic abnormalities in the chronic phase. The results indicate that complex pathophysiological processes differ depending on the post-injury phase and the neurometabolite in question.

Auditory processing after sport-related concussions.

OBJECTIVE: The aim of the study is to investigate whether sport-related concussions disrupt auditory processes. DESIGN: Sixteen university athletes participated in the study: eight had one or more sport-related concussions, and eight never experienced a concussion. The Frequency Pattern Sequence test, the Duration Pattern Sequence test, the Synthetic Sentence Identification test, and the Staggered Spondaic Word test were used to assess auditory processing. RESULTS: All nonconcussed athletes have normal auditory processing. In contrast, more than half of the concussed athletes had deficits for one or more of the auditory processing tests. CONCLUSIONS: The pattern of results suggests that sport-related concussions can disrupt the neurological mechanisms implicated in several auditory processes, including monaural low-redundancy speech recognition, tone pattern recognition, and dichotic listening.

Elite Male Volleyball Players Are at Risk of Insufficient Energy and Carbohydrate Intake.

Elite volleyball athletes experience significant physical and psychological demands during the competitive season. The aim was to compare the dietary intake of male volleyball athletes with recommendations for sport and health, and to examine the association of physique traits and knee health on eating behaviours and of eating behaviours on reported dietary intake. Using a retrospective cross-sectional design, 22 male athletes from a national indoor volleyball program underwent anthropometric, dual-energy X-ray absorptiometry and resting metabolic rate testing, 4-day dietary intake and hematological analysis, and also completed the three-factor eating questionnaire-R18 for eating behaviours and the Victorian Institute of Sport Assessment-patellar tendon (VISA-P) questionnaire for knee health. Most players under-consumed energy compared to reference guidelines, secondary to under-consuming carbohydrate for exercise. The primary eating behaviour was cognitive restraint, which was associated with body mass index and ectomorphy. Emotional eating behaviour was associated with VISA-P. Differences in emotional and cognitive restraint eating behaviours did not impact dietary intake. The findings suggest that players are at risk of an impaired ability to adapt to and recover from training during an important segment of the competitive season. Future work should explore the presence of low energy availability in elite male volleyball players.

Exercise-Based Injury Prevention in High-Level and Professional Athletes: Narrative Review and Proposed Standard Operating Procedure for Future Lockdown-Like Contexts After COVID-19.

In regular times, implementing exercise-based injury prevention programs into the training routine of high-level and professional athletes represents a key and challenging aspect to decrease injury risk. Barriers to implementing such prevention programs have previously been identified such as lack of resources, logistic issues or motivation. The COVID-19 pandemic associated with restrictions on daily life dramatically impacted sports participation from training to competition. It is therefore reasonable to assume that such lockdown-like context has exacerbated the challenge to implement exercise-based injury prevention programs, potentially leading to a greater musculoskeletal injury risk. In this narrative review, recommendations are proposed for building an expertise- and evidence-based Standard Operating Procedure for injury prevention in lockdown-like contexts for high-level and professional athletes. The following recommendations can be provided: (1) assess the global and sport-specific risks in the light of the ongoing cause of isolation; (2) adapt remote training materials and programs; (3) ensure regular quality communication within the staff, between athletes and the staff as well as between athletes; (4) follow the athlete's mental well-being; and (5) plan for a safe return-to-sports as well as for an ongoing monitoring of the load-recovery balance. These key domains should further be addressed to comply with local policies, which are subject to change over time in each individual country. The use of these recommendations may improve the readiness of athletes, coaches, physicians and all sports stakeholders for future lockdown-like contexts.

Brain function decline in healthy retired athletes who sustained their last sports concussion in early adulthood.

Recent studies have shown that the detrimental effects of sports concussions on cognitive and motor function may persist up to a few years post-injury. The present study sought to investigate the effects of having sustained a sports concussion more than 30 years prior to testing on cognitive and motor functions. Nineteen healthy former athletes, in late adulthood (mean age = 60.79; SD = 5.16), who sustained their last sport-related concussion in early adulthood (mean age = 26.05; SD = 9.21) were compared with 21 healthy former athletes with no history of concussion (mean age = 58.89; SD = 9.07). Neuropsychological tests sensitive to age-related changes in cognition were administered. An auditory oddball paradigm was used to evoke P3a and P3b brain responses. Four TMS paradigms were employed to assess motor cortex excitability: (i) resting motor threshold; (ii) paired-pulse intracortical inhibition and intracortical facilitation; (iii) input/output curve and (iv) cortical silent period (CSP). A rapid alternating movement task was also used to characterize motor system dysfunctions. Relative to controls, former athletes with a history of concussion had: (i) lower performance on neuropsychological tests of episodic memory and response inhibition; (ii) significantly delayed and attenuated P3a/P3b components; (iii) significantly prolonged CSP and (iv) significantly reduced movement velocity (bradykinesia). The finding that the P3, the CSP as well as neuropsychological and motor indices were altered more than three decades post-concussion provides evidence for the chronicity of cognitive and motor system changes consecutive to sports concussion.

Sleep following sport-related concussions.

OBJECTIVES: Sleep and vigilance disorders are among the most commonly reported symptoms following a concussion. The aim of the study was thus to investigate the effects of sport-related concussions on subjective and objective sleep quality. METHODS: Ten concussed athletes and 11 non-concussed athletes were included. Concussed athletes had a history of 4.6+/-2.1 concussions with at least one concussion during the last year. They were recorded for two consecutive nights in the laboratory and during a 10-min period of wakefulness. They completed questionnaires related to sleep quality and symptoms as well as neuropsychological tests and the CogSport computer battery. RESULTS: Concussed athletes reported more symptoms and worse sleep quality than control athletes, but no between-group differences were found on polysomnographic variables or on REM and NREM sleep quantitative EEG variables. However, concussed athletes showed significantly more delta activity and less alpha activity during wakefulness than did control athletes. CONCLUSION: In spite of the subjective complaints in sleep quality of concussed athletes, no change was observed in objective sleep characteristics. However, concussions were associated with an increase in delta and a reduction in alpha power in the waking EEG. Sport-related concussions are thus associated with wakefulness problems rather than sleep disturbances.

One-year test-retest reliability of ten vision tests in Canadian athletes.

Background: Vision tests are increasingly being suggested for use in concussion management and baseline testing. Concussions, however, often occur months after baseline testing and reliability studies generally examine intervals limited to days or one week. Therefore, our objective was to determine the one-year test-retest reliability of these tests. Methods: We assessed one-year test-retest reliability of ten vision tests in elite Canadian athletes followed by the Institut National du Sport du Quebec. We included athletes who completed two baseline (preseason) annual evaluations by one clinician within 365±30 days. We excluded athletes with any concussion or vision training in between the annual evaluations or presented with any factor that is believed to affect the tests (e.g. migraines, etc.). Data were collected from clinical charts. We evaluated test-retest reliability using Intraclass Correlation Coefficient (ICC) and 95% limits of agreement (LoA). Results: We examined nine female and seven male athletes with a mean age of 22.7 (SD 4.5) years. Among the vision tests, we observed excellent test-retest reliability in Positive Fusional Vergence at 30cm (ICC=0.93) but this dropped to 0.55 when an outlier was excluded in a sensitivity analysis. There was good to moderate reliability in Negative Fusional Vergence at 30cm (ICC=0.78), Phoria at 30cm (ICC=0.68), Near Point of Convergence break (ICC=0.65) and Saccade (ICC=0.56). The ICC for Positive Fusional Vergence at 3m (ICC=0.56) also decreased to 0.21 after removing one outlier. We found poor reliability in Near Point of Convergence (ICC=0.47), Gross Stereoscopic Acuity (ICC=0.03) and Negative Fusional Vergence at 3m (ICC=0.0). ICC for Phoria at 3m was not appropriate because scores were identical in 14/16 athletes. 95% LoA of the majority of tests were ±40% to ±90%. Conclusions: Four tests had moderate one-year test-retest reliability. The remaining tests had poor reliability. The tests would therefore be useful only if concussion has a moderate-large effect on scores.

Persistent motor system abnormalities in formerly concussed athletes.

CONTEXT: The known detrimental effects of sport concussions on motor system function include balance problems, slowed motor execution, and abnormal motor cortex excitability. OBJECTIVE: To assess whether these concussion-related alterations of motor system function are still evident in collegiate football players who sustained concussions but returned to competition more than 9 months before testing. DESIGN: Case-control study. SETTING: University laboratory. PATIENTS OR OTHER PARTICIPANTS: A group of 21 active, university-level football players who had experienced concussions was compared with 15 university football players who had not sustained concussions. INTERVENTION(S): A force platform was used to assess center-of-pressure (COP) displacement and COP oscillation regularity (approximate entropy) as measures of postural stability in the upright position. A rapid alternating-movement task was also used to assess motor execution speed. Transcranial magnetic stimulation over the motor cortex was used to measure long-interval intracortical inhibition and the cortical silent period, presumably reflecting y-aminobutyric acid subtype B receptor-mediated intracortical inhibition. MAIN OUTCOME MEASURE(S): COP displacement and oscillation regularity, motor execution speed, long-interval intracortical inhibition, cortical silent period. RESULTS: Relative to controls, previously concussed athletes showed persistently lower COP oscillation randomness, normal performance on a rapid alternating-movement task, and more M1 intracortical inhibition that was related to the number of previous concussions. CONCLUSIONS: Sport concussions were associated with pervasive changes in postural control and more M1 intracortical inhibition, providing neurophysiologic and behavioral evidence of lasting, subclinical changes in motor system integrity in concussed athletes.

Prolonged neuropsychological impairments following a first concussion in female university soccer athletes.

OBJECTIVE: Although research is accumulating on the cognitive sequelae from sports-related concussions in men, little to nothing is known about the prolonged cognitive outcome after a concussion in women. This point is important because recent evidence suggests that female athletes are at greater risk of sustaining a concussion. DESIGN: We assessed cognitive functioning after a first concussion in female soccer players, 6 to 8 months after their injury. The first-time concussed athletes were compared with a group of age-matched teammates who had never experienced a concussion. SETTING AND PARTICIPANTS: A total of 22 female university-level soccer players participated in the study. MAIN OUTCOME MEASUREMENTS: Paper-and-pencil and computerized tasks were used to assess different neuropsychological functions. RESULTS: Short- and long-term verbal memory, attention, and simple reaction time were normal. In contrast, compared with the control group, the concussed athletes were significantly slower on tasks that required decision making (complex reaction time), inhibition and flexibility (Stroop), and planning (Tour of London task). CONCLUSIONS: The results of this study suggest that cognitive functions related to cognitive processing speed are most vulnerable to a sports-related concussion and are still impaired for a half year after injury in university-level female soccer players.

Long-term and cumulative effects of sports concussion on motor cortex inhibition.

OBJECTIVE: Using transcranial magnetic stimulation paradigms, this study investigated motor cortex integrity as a function of an athlete's prior history of concussions. PATIENTS AND METHODS: Motor cortex excitatory and inhibitory mechanisms were studied in athletes using four different transcranial magnetic stimulation protocols, namely 1) resting motor threshold, 2) intracortical inhibition and intracortical facilitation in a paired-pulse paradigm, 3) excitability of the corticospinal system using an input-output curve, and 4) intracortical inhibition in a cortical silent-period paradigm. Motor-evoked potentials were recorded from the first dorsal interosseous muscle of the right hand. RESULTS: Cortical silent-period duration in athletes who have experienced multiple concussions was prolonged when compared to that of normal control participants. Linear regression suggested that concussion severity was the main factor explaining motor cortex dysfunction. Moreover, when we retested the athletes, the cortical silent period was more prolonged in those who sustained another concussion after baseline testing had occurred. CONCLUSION: Findings from this study indicate that sports-related concussions result in long-term motor system dysfunctions that seem to be attributable to subclinical intracortical inhibitory system abnormalities. This study also shows that sustaining subsequent concussions exacerbates this deficit, and thus provides additional support for the contention that the adverse effects of sports-related concussions on intracortical inhibitory systems are cumulative.

Neurophysiological anomalies in symptomatic and asymptomatic concussed athletes.

OBJECTIVE: Concussion in sports is a problem of such magnitude that improvements in diagnosis and management are desirable. The aim of the present study was to investigate the effect of concussion on event-related potentials, in symptomatic as well as in asymptomatic athletes. METHODS: Twenty symptomatic and asymptomatic athletes who sustained a concussion were compared with 10 control athletes in a modified auditory Oddball task. The task included a sequence of tones containing standard and deviant stimuli. Participants were asked to respond to the target tone presented in the left ear and to ignore tones presented in the right ear. The electroencephalogram was recorded from 28 electrodes during the task. RESULTS: The results showed a reduction in the amplitude of N1, P2, and P3 components in symptomatic and asymptomatic athletes in comparison with control athletes. No between-group differences were observed in reaction times or in latency of the event-related potentials components, except for P3 latency, in which the controls showed shorter latency than the concussed groups. CONCLUSION: Concussions seem to produce deficits in the early and late stages of auditory information processing, which possibly reflect impaired brain functioning in symptomatic and asymptomatic concussed athletes. The fact that asymptomatic athletes have an electrophysiological profile similar to that of symptomatic athletes challenges the validity of return-to-play guidelines for which the absence of symptoms is a major issue.

Visual p300 effects beyond symptoms in concussed college athletes.

In order to assess whether cerebral anomalies may be observed in the absence of clinical symptoms, the current study compared the effects of concussions on attentional capacities (reaction times, accuracy) and Event-Related Potentials (ERPs) in concussed athletes with (n = 10) or without (n = 10) symptoms as well as in athletes who never had a concussion (n = 10). The P300 response was recorded from 28 electrodes during a modified visual oddball paradigm. Participants were instructed to press a key upon the appearance of the frequent stimuli as well as when a rare nontarget stimulus followed the frequent one. The other key was to be pressed when the subsequent rare stimuli (rare target) appeared until a frequent one reappeared. The symptomatic athletes displayed longer reaction times than the other two groups of athletes. The P300 amplitude to the rare target stimuli was significantly more attenuated in the symptomatic athletes than in the other two groups. Moreover, the P300 amplitude varied inversely with the severity of post-concussion symptoms but was not influenced by time elapsed since injury. Although the clinical significance of the P300 differences shown by the symptomatic athletes is still uncertain, the results do indicate that symptom severity may be a crucial indicator of functional impairments following mild traumatic brain injury.

Concussions among university football and soccer players.

OBJECTIVE: A study to examine the incidence and characteristics of concussions among Canadian university athletes during 1 full year of football and soccer participation. DESIGN: Retrospective survey. PARTICIPANTS: Three hundred eighty Canadian university football and 240 Canadian university soccer players reporting to 1999 fall training camp. Of these, 328 football and 201 soccer players returned a completed questionnaire. MAIN OUTCOME MEASURES: Based on self-reported symptoms, calculations were made to determine the number of concussions experienced during the previous full year of football or soccer participation, the duration of symptoms, the time for return to play, and any associated risk factors for concussions. RESULTS: Of all the athletes who returned completed questionnaires, 70.4% of the football players and 62.7% of the soccer players had experienced symptoms of a concussion during the previous year. Only 23.4% of the concussed football players and 19.8% of the concussed soccer players realized they had suffered a concussion. More than one concussion was experienced by 84.6% of the concussed football players and 81.7% of the concussed soccer players. Examining symptom duration, 27.6% of all concussed football players and 18.8% of all concussed soccer players experienced symptoms for at least 1 day or longer. Tight end and defensive lineman were the positions most commonly affected in football, while goalies were the players most commonly affected in soccer. Variables that increased the odds of suffering a concussion during the previous year for football players included a history of a traumatic loss of consciousness or a recognized concussion in the past. Variables that increased the odds of suffering a concussion during the previous year for soccer players included a past history of a recognized concussion while playing soccer and being female. CONCLUSIONS: University football and soccer players seem to be experiencing a significant amount of concussions while participating in their respective sports. Variables that seem to increase the odds of suffering a concussion during the previous year for football and soccer players include a history of a recognized concussion. Despite being relatively common, symptoms of concussion may not be recognized by many players.