Retinal detachment following hockey injury.

Thirty-three cases of retinal detachment following hockey injury were seen during a 15-year period at the retina clinic of Maisonneuve-Rosemont Hospital, Montreal. Most injuries occurred in adolescents, the average age being 18 years. The mean interval between injury and preoperative examination was 3 years. Almost half of these young hockey players remained legally blind in the affected eye even after a successful operation. A helmet with a protective face visor is suggested as the best prevention against severe ocular damage such as retinal detachment.     

Eye injuries associated with war games

War games, an outdoor activity combining recreation, military maneuvers and fantasy, are becoming a popular recreational sport. Increasing numbers of players are suffering eye injuries. In the last year 26 cases of serious eye injuries were reported to Canadian ophthalmologists; in 15 eyes vision was reduced to 6/24 or less. Although eyeguards are provided, all the injuries had occurred when the participants were not wearing them. Methods of preventing eye injuries in war games are discussed.     

National survey of spinal injuries in hockey players.

There has been an alarming increase in the number of spinal injuries in hockey players. Between 1976 and 1983, 42 were reported to the Committee on Prevention of Spinal Injuries due to Hockey. The median age of the injured players was 17 years. Of the 42 players 28 had spinal cord injuries, and 17 of them had complete paralysis below the vertebral level of the injury. Strikes from behind and collisions with the boards were common mechanisms of injury. Many of the players had suffered a burst fracture of the cervical spine following a blow to the top of the helmet when the neck was slightly flexed. The committee studied a number of possible etiologic factors and made several recommendations regarding prevention. League officials, coaches, players and equipment manufacturers can all play a role in prevention.     

Effectiveness of interventions to reduce aggression and injuries among ice hockey players: a systematic review

Background:

The increasing incidence of injuries related to playing ice hockey is an important public health issue. We conducted a systematic review to evaluate the effectiveness of interventions designed to reduce injuries related to aggressive acts in ice hockey.

Methods:

We identified relevant articles by searching electronic databases from their inception through July 2012, by using Internet search engines, and by manually searching sports medicine journals, the book series Safety in Ice Hockey and reference lists of included articles. We included studies that evaluated interventions to reduce aggression-related injuries and reported ratings of aggressive behaviour or rates of penalties or injuries.

Results:

We identified 18 eligible studies. Most involved players in minor hockey leagues. Of 13 studies that evaluated changes in mandatory rules intended to lessen aggression (most commonly the restriction of body-checking), 11 observed a reduction in penalty or injury rates associated with rule changes, and 9 of these showed a statistically significant decrease. The mean number of penalties decreased by 1.2–5.9 per game, and injury rates decreased 3- to 12-fold. All 3 studies of educational interventions showed a reduction in penalty rates, but they were not powered or designed to show a change in injury rates. In 2 studies of cognitive behavioural interventions, reductions in aggressive behaviours were observed.

Interpretation:

Changes to mandatory rules were associated with reductions in penalties for aggressive acts and in injuries related to aggression among ice hockey players. Effects of educational and cognitive behavioural interventions on injury rates are less clear. Well-designed studies of multifaceted strategies that combine such approaches are required.Over the last 15 years, the incidence of brain and spinal cord injuries among ice hockey players has increased.¹ A recent study involving players in junior leagues found that, in the 2009/10 hockey season, the incidence of game-related concussions was 7 times higher than the highest rate previously reported in 1998/99.² Brain injuries frequently result from aggressive bodychecking³ and account for 15% of injuries among players 9–16 years of age.^4,5 In a study of a community-based hockey program involving boys aged 9–15 years, hostile aggressive acts, which have an intention to do harm,⁶ were the primary cause of injury in one-third of games in which an injury resulted.⁷ Among high school students in Minnesota who played varsity ice hockey, those who played to relieve aggression were 4 times more likely than other players to experience a concussion.⁸ These findings highlight the association between aggressive behaviour and injury in ice hockey. However, little is known about what can be done to reduce this behaviour to create a safer environment for the sport.Existing reviews about reducing injury in sport have primarily assessed equipment or risk factors associated with injury.^9–11 Recent systematic reviews highlighted the risks of bodychecking and renewed calls for policies to disallow bodychecking among youth playing ice hockey.^3,12 We conducted a systematic review to assess the effectiveness of interventions designed to reduce aggressive acts and related injuries among ice hockey players. We were particularly interested in evaluating the effectiveness of rule changes, educational interventions and behavioural modification in reducing aggressive acts and related injuries.     

Disorders of the Menstrual Cycle in Elite Female Ice Hockey Players and Figure Skaters

The purpose of this study was to assess and compare the incidence of delayed menarche and menstrual dysfunction among elite ice hockey players and figure skaters. Forty-three ice hockey players (23.5 ± 4.8 years, 68.2 ± 1.2 kg, 1.68 ± 0.01 m) and 39 figure skaters (17.5 ± 3.4 years, 53.7 ± 5.8 kg, 1.64 ± 0.05 m) completed a self-administered questionnaire on their menstrual status and history, training regimens and lifestyle. Age at menarche did not differ significantly between ice hockey players (13.3 ± 1.3 years) and figure skaters (13.7 ± 1.4 years). Menarche was unrelated to nationality, vigorous training premenarche or age at which the athlete began her sport, but was correlated with the age at menarche of the athletes’ mothers (r = 0.39, p < 0.05). Hormonal contraceptives were used by 35% of ice hockey players and 15% of the figure skaters. Amenorrhea and oligomenorrhea were experienced by 7.1% and 38.7% of postmenarcheal, ice hockey players and figure skaters respectively not using hormonal contraceptives. Menstrual dysfunction was associated with both age and age at menarche in the ice hockey players only. Training factors, and psychological pressure were perceived by the athletes to contribute to menstrual dysfunction. A greater training volume, younger age at commencing sport, lower body mass, greater subjective body image pressure and younger biological and gynaecological age were reported among the figure skaters, and were proposed to explain the higher incidence of menstrual dysfunction among the figure skaters compared with the ice hockey players. Figure skaters appear at increased risk of amenorrhea and oligomenorrhea compared with ice hockey players, which may be linked to training and physical characteristics of the sports.     

In your face: facial metrics predict aggressive behaviour in the laboratory and in varsity and professional hockey players

Facial characteristics are an important basis for judgements about gender, emotion, personality, motivational states and behavioural dispositions. Based on a recent finding of a sexual dimorphism in facial metrics that is independent of body size, we conducted three studies to examine the extent to which individual differences in the facial width-to-height ratio were associated with trait dominance (using a questionnaire) and aggression during a behavioural task and in a naturalistic setting (varsity and professional ice hockey). In study 1, men had a larger facial width-to-height ratio, higher scores of trait dominance, and were more reactively aggressive compared with women. Individual differences in the facial width-to-height ratio predicted reactive aggression in men, but not in women (predicted 15% of variance). In studies 2 (male varsity hockey players) and 3 (male professional hockey players), individual differences in the facial width-to-height ratio were positively related to aggressive behaviour as measured by the number of penalty minutes per game obtained over a season (predicted 29 and 9% of the variance, respectively). Together, these findings suggest that the sexually dimorphic facial width-to-height ratio may be an 'honest signal' of propensity for aggressive behaviour.     

TRAINING-INDUCED CHANGES IN DRAG-FLICK TECHNIQUE IN FEMALE FIELD HOCKEY PLAYERS

The penalty corner is one of the most important goal plays in field hockey. The drag-flick is used less by women than men in a penalty corner. The aim of this study was to describe training-induced changes in the drag-flick technique in female field hockey players. Four female players participated in the study. The VICON optoelectronic system (Oxford Metrics, Oxford, UK) measured the kinematic parameters of the drag-flick with six cameras sampling at 250 Hz, prior to and after training. Fifteen shots were captured for each subject. A Wilcoxon test assessed the differences between pre-training and post-training parameters. Two players received specific training twice a week for 8 weeks; the other two players did not train. The proposed drills improved the position of the stick at the beginning of the shot (p < 0.05), the total distance of the shot (p < 0.05) and the rotation radius at ball release (p < 0.01). It was noted that all players had lost speed of the previous run. Further studies should include a larger sample, in order to provide more information on field hockey performance.     

8. Blessures au hockey majeur: 3 ans d'étude

In a major junior hockey team there were 238 injuries in 257 games during the three seasons of 1973-76 (mean number of injuries per game, 0.926). Incapacity from these injuries resulted in a loss of 345 practices and 299 games (mean number per injury, 1.45 and 1.26, respectively). The site of the game, whether at home or out of town, and the period in which the injury occurred did not seem to be important. Risk of injury seemed to be greatest in the defensive zone. Forwards were the most often injured, their injuries accounting for 45.8% of the total; defensive players were next most often hurt (31.9%). The age of the injured players ranged from 16 to 19 years, those 19 years old predominating (42.0%).There were 91 injuries of the lower limb (38.2% of the total), the knee being the site most frequently injured (31 injuries; 34.1% of the 91), and 74 injuries of the upper limb, the shoulder being the site most frequently injured (25 injuries; 33.8% of the 74). The main causes of injury were a blow by the puck (frequency, 21.0%), a check (18.5%), a blow by a stick (14.7%) and a fight (13.4%).     

Risk of injury associated with bodychecking experience among youth hockey players

Background:

In a previous prospective study, the risk of concussion and all injury was more than threefold higher among Pee Wee ice hockey players (ages 11–12 years) in a league that allows bodychecking than among those in a league that does not. We examined whether two years of bodychecking experience in Pee Wee influenced the risk of concussion and other injury among players in a Bantam league (ages 13–14) compared with Bantam players introduced to bodychecking for the first time at age 13.

Methods:

We conducted a prospective cohort study involving hockey players aged 13–14 years in the top 30% of divisions of play in their leagues. Sixty-eight teams from the province of Alberta (n = 995), whose players had two years of bodychecking experience in Pee Wee, and 62 teams from the province of Quebec (n = 976), whose players had no bodychecking experience in Pee Wee, participated. We estimated incidence rate ratios (IRRs) for injury and for concussion.

Results:

There were 272 injuries (51 concussions) among the Bantam hockey players who had bodychecking experience in Pee Wee and 244 injuries (49 concussions) among those without such experience. The adjusted IRRs for game-related injuries and concussion overall between players with bodychecking experience in Pee Wee and those without it were as follows: injury overall 0.85 (95% confidence interval [CI] 0.63 to 1.16); concussion overall 0.84 (95% CI 0.48 to 1.48); and injury resulting in more than seven days of time loss (i.e., time between injury and return to play) 0.67 (95% CI 0.46 to 0.99). The unadjusted IRR for concussion resulting in more than 10 days of time loss was 0.60 (95% CI 0.26 to 1.41).

Interpretation:

The risk of injury resulting in more than seven days of time loss from play was reduced by 33% among Bantam hockey players in a league where bodychecking was allowed two years earlier in Pee Wee compared with Bantam players introduced to bodychecking for the first time at age 13. In light of the increased risk of concussion and other injury among Pee Wee players in a league where bodychecking is permitted, policy regarding the age at which hockey players are introduced to bodychecking requires further consideration.Rates of participation in youth-level ice hockey are high in North America.^1,2 There is growing concern regarding the impact of concussion in this population.^3–5 Body-checking is the reported mechanism for 45%–86% of injuries in youth ice hockey.^5–11 Internationally, the age group at which bodychecking is introduced varies. In Canada, bodychecking is introduced in Pee Wee leagues (ages 11–12 years), except in the province of Quebec, where it is introduced in Bantam (ages 13–14).¹²The age at which bodychecking should be introduced is controversial. We recently reported that the risk of injury and concussion in a Pee Wee league that allows bodychecking was more than threefold higher than in a Pee Wee league that does not allow bodychecking.⁹ Findings from systematic reviews support these findings.^13,14Injury rates may increase when players begin to learn bodychecking, because it is a new skill. If so, injury rates would be expected to be higher among players without bodychecking experience in Pee Wee (i.e., those in Quebec) than among players introduced to body-checking two years earlier in Pee Wee (e.g., in Alberta). We examined whether the risk of concussion and other injury among hockey players in Bantam leagues differed between players with and those without bodychecking experience in Pee Wee.     

Utilizing the Quantitative Electroencephalograph (qEEG) to Objectively Document the Nature and Severity of Concussions in Junior Hockey Players: A Pilot Investigation

Concussions represent a major concern for hockey teams. During one winter season, all players on two Junior Hockey Teams were assessed in order to establish an incidence baseline for concussions. The qEEG was utilized as it measures the probability of concussion and its severity. The SCL 90-R and CNS questionnaire were used to provide insight into various aspects of cognitive functioning. Results indicated that of the players assessed (N?=?46) approximately two-thirds (N?=?32) tested positive for concussions. A minority of the concussions were assessed as mild (N?=?13), while 19 were assessed as moderately severe. The most common sites indicated as injured were F8 and T6 (right side of head) and O1 and O2 (back of head) and F7 (left front of head). A comparison of the questionnaire results to expected behavioural issues are discussed. This appears to be one of the first studies of junior hockey players using an objective measure of study (qEEG).     

Development of national system performance metrics for tissue donation,production, and distribution activity

Canada’s federal, provincial, and territorial governments gave Canadian Blood Services a mandate for organ and tissue donation and transplantation, including system performance, data and analytics. In 2012 Canadian Blood Services facilitated an eye and tissue banking workshop focused on standardized specifications and practices. At the workshop, the Canadian tissue community directed Canadian Blood Services to facilitate the development and implementation of a national data stream and analytics. Prior to this no national data was prospectively collected or collated on tissue donation, production or distribution activity. An eye and tissue data committee was formed with representation from eye and tissue banks in all Canadian jurisdictions. A minimum data set, standardized definitions, a data submission form and a quality assurance process was developed. Training was provided to data personal identified by each eye and tissue bank. Data collection was initiated January 1, 2013; with quarterly data submitted to Canadian Blood Services via excel spreadsheet. Data was submitted by sixteen Canadian eye and tissue banks, located in eight of Canada’s thirteen provinces and territories, representing a census of activity. Annual data reports, with trend analysis, are generated and distributed to the tissue community to inform operational strategy and system performance improvement. This report provides an overview of the data process and provides visibility to the Canadian tissue donation, production and distribution activities for 3 years; January 1, 2013 to December 31, 2015.     

Relationship of physical fitness test results and hockey playing potential in elite-level ice hockey players

The primary purpose of this study was to determine the fitness variables with the highest capability for predicting hockey playing potential at the elite level as determined by entry draft selection order. We also examined the differences associated with the predictive abilities of the test components among playing positions. The secondary purpose of this study was to update the physiological profile of contemporary hockey players including positional differences. Fitness test results conducted by our laboratory at the National Hockey League Entry Draft combine were compared with draft selection order on a total of 853 players. Regression models revealed peak anaerobic power output to be important for higher draft round selection in all positions; however, the degree of importance of this measurement varied with playing position. The body index, which is a composite score of height, lean mass, and muscular development, was similarly important in all models, with differing influence by position. Removal of the goalies' data increased predictive capacity, suggesting that talent identification using physical fitness testing of this sort may be more appropriate for skating players. Standing long jump was identified as a significant predictor variable for forwards and defense and could be a useful surrogate for assessing overall hockey potential. Significant differences exist between the physiological profiles of current players based on playing position. There are also positional differences in the relative importance of anthropometric and fitness measures of off-ice hockey tests in relation to draft order. Physical fitness measures and anthropometric data are valuable in helping predict hockey playing potential. Emphasis on anthropometry should be used when comparing elite-level forwards, whereas peak anaerobic power and fatigue rate are more useful for differentiating between defense.     

Myelin Water Fraction Is Transiently Reduced after a Single Mild Traumatic Brain Injury – A Prospective Cohort Study in Collegiate Hockey Players

Impact-related mild traumatic brain injuries (mTBI) are a major public health concern, and remain as one of the most poorly understood injuries in the field of neuroscience. Currently, the diagnosis and management of such injuries are based largely on patient-reported symptoms. An improved understanding of the underlying pathophysiology of mTBI is urgently needed in order to develop better diagnostic and management protocols. Specifically, dynamic post-injury changes to the myelin sheath in the human brain have not been examined, despite ‘compromised white matter integrity’ often being described as a consequence of mTBI. In this preliminary cohort study, myelin water imaging was used to prospectively evaluate changes in myelin water fraction, derived from the T2 decay signal, in two varsity hockey teams (45 players) over one season of athletic competition. 11 players sustained a concussion during competition, and were scanned at 72 hours, 2 weeks, and 2 months post-injury. Results demonstrated a reduction in myelin water fraction at 2 weeks post-injury in several brain areas relative to preseason scans, including the splenium of the corpus callosum, right posterior thalamic radiation, left superior corona radiata, left superior longitudinal fasciculus, and left posterior limb of the internal capsule. Myelin water fraction recovered to pre-season values by 2 months post-injury. These results may indicate transient myelin disruption following a single mTBI, with subsequent remyelination of affected neurons. Myelin disruption was not apparent in the athletes who did not experience a concussion, despite exposure to repetitive subconcussive trauma over a season of collegiate hockey. These findings may help to explain many of the metabolic and neurological deficits observed clinically following mTBI.     

Field hockey players have different values of ulnar and tibial motor nerve conduction velocity than soccer and tennis players

The aim of this study was to describe motor nerve conduction velocity in upper and lower extremities in sportsmen. Fifteen high-level field hockey players, seventeen soccer players and ten tennis players were recruited from the Polish National Field Hockey League, Polish Soccer League Clubs, and Polish Tennis Association clubs,respectively. The control group comprised of seventeen healthy, non-active young men. Nerve conduction velocities of ulnar and tibial nerve were assessed with NeuroScreen electromyograph (Toennies, Germany) equipped with standard techniques of supramaximal percutaneus stimulation with constant current and surface electrodes. No significant differences in motor nerve conduction velocities were found between dominant and non-dominant limbs in each studied group. Ulnar nerve conduction velocity measured from above elbow to below elbow was significantly lower only in the field hockey players' dominant limb. Tibial conduction velocity of the field hockey players' non-dominant lower limb was higher in comparison to the tennis players and the control group. There was no significant correlation between body mass and NCV as well as between height of subjects and NCV in both athletes or non-athletes. A slight trend towards a lower TCV values in athletes with longer duration of practicing sport was found. It was most pronounced in the non-dominant lower extremity of field hockey players.     

Evaluation of jump protocols to assess leg power and predict hockey playing potential

The purposes of this study were (a) to determine the measurement device and jumping protocol most appropriate for testing the leg power of elite hockey players and (b) to assess the relationship of leg power measurements to hockey playing ability as indicated by draft selection order. Comparisons were made of leg power measurements from the top 95 players entering the National Hockey League Entry Draft using 2 devices (Vertec and Just Jump) and 2 jump protocols (countermovement and squat). Players' leg powers were ranked from highest to lowest power using each device and protocol and were correlated with draft selection order. Vertec leg power measurements were highest (5,511-5,631 W), but there were no significant differences in power between the 2 jumping protocols on either device. Vertec squat jump provided the highest correlation (0.47) between leg power ranking and selection order and was judged to most closely approximate the full-body coordinated movements involved in hockey. The Vertec device using a squat jump protocol is most appropriate for coaches and fitness specialists to use when evaluating hockey potential based on the off-ice leg power measurements of elite hockey players.     

Intensity,repetitiveness, and directionality of habitual adolescent mobility patterns influence the tibial diaphysis morphology of athletes

Mobility patterns affect the loads placed on the lower limbs during locomotion and may influence variation in lower limb diaphyseal robusticity and shape. This relationship commonly forms the basis for inferring mobility patterns from hominin fossil and skeletal remains. This study assesses the correspondence between athletic histories, varying by loading intensity, repetition and directionality, measured using a recall questionnaire, and peripheral quantitative computed tomography‐derived measurements of tibial diaphysis rigidity and shape. Participants included male university varsity cross‐country runners (n = 15), field hockey players (n = 15), and controls (n = 20) [mean age: 22.1 (SD +/? 2.6) years]. Measurements of tibial rigidity (including J, %CA, I_max, I_min, and average cortical thickness) of both runners and field hockey players were greater than controls (P ≤ 0.05). Differences in tibial shape (I_max/I_min, P ≤ 0.05) between runners and hockey players reflect pronounced maximum plane (I_max) rigidity in runners, and more symmetrical hypertrophy (I_max, I_min) among hockey players. This corresponds with the generally unidirectional locomotor patterns of runners, and the multidirectional patterns of hockey players. These results support the relationship between mobility and tibial diaphysis morphology as it is generally interpreted in the anthropological literature, with greater levels of mobility associated with increased diaphyseal robusticity and shape variation. Although exercise intensity may be the primary influence on these properties, the repetitiveness of the activity also deserves consideration. In conclusion, bone morphological patterns can reflect habitual behaviors, with adaptation to locomotor activities likely contributing to variation in tibial rigidity and shape properties in archaeological and fossil samples. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.     

Acute injuries in soccer,ice hockey,volleyball, basketball,judo, and karate: analysis of national registry data.

OBJECTIVE--To determine the acute injury profile in each of six sports and compare the injury rates between the sports. DESIGN--Analysis of national sports injury insurance registry data. SETTING--Finland during 1987-91. SUBJECTS--621,691 person years of exposure among participants in soccer, ice hockey, volleyball, basketball, judo, or karate. MAIN OUTCOME MEASURES--Acute sports injuries requiring medical treatment and reported to the insurance company on structured forms by the patients and their doctors. RESULTS--54,186 sports injuries were recorded. Injury rates were low in athletes aged under 15, while 20-24 year olds had the highest rates. Differences in injury rates between the sports were minor in this adult age group. Overall injury rates were higher in sports entailing more frequent and powerful body contact. Each sport had a specific injury profile. Fractures and dental injuries were most common in ice hockey and karate and least frequent in volleyball. Knee injuries were the most common cause of permanent disability. CONCLUSIONS--Based on the defined injury profiles in the different sports it is recommended that sports specific preventive measures should be employed to decrease the number of violent contacts between athletes, including improved game rules supported by careful refereeing. To prevent dental injuries the wearing of mouth guards should be encouraged, especially in ice hockey, karate, and basketball.     

Gender differences in hockey players during on-ice graded exercise

The purpose of this study was to examine whether gender differences exist for ventilatory threshold (VT), lactate threshold (LT), and Vo2max during on-ice skating in college hockey players. Ten male and 10 female Division III college hockey players performed a graded exercise skating protocol until reaching volitional fatigue. The graded exercise test employed stages that were 80 seconds in duration, with 40 seconds of rest between each stage to obtain blood lactate samples. Ventilatory threshold occurred at a higher percentage of maximal heart rate (HRmax) in women than in men. The women's VT occurred at 77.3% +/- 1.6% HRmax, while the men's VT occurred at 72.6% +/- 2.0% HRmax (p < 0.02). Men and women had similar HRmax values: 191.3 +/- 2.5 b.min and 185.8 +/- 2.5 b.min, respectively. Vo2max was different between genders, with men at 52.7 +/- 1.3 mL.kg.min and women at 40.1 +/- 1.0 mL.kg.min (p < 0.01). In addition, VT was different between genders when measured as a percentage of Vo2max, with men at 52.7% +/- 3.2% and women at 67.3% +/- 4.0% (p < 0.02). In contrast, LT was similar between genders when expressed as a percentage of HRmax or Vo2max. For each gender, LT occurred at a significantly higher percentage of HRmax or Vo2max than VT did. It can be concluded that VT does not accurately predict LT in male or female hockey players. Additionally, competitive female hockey players have a lower Vo2max but a higher VT than their male counterparts. An increased VT may be a compensatory mechanism to offset the smaller Vo2max values measured in female hockey players. On-ice testing is a practical way to address specific aerobic training needs of hockey players.