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%).     

Training injuries in rugby league: an evaluation of skill-based conditioning games

This study investigated the site and nature of rugby league training injuries, and identified the training activities that were most likely to result in injury in rugby league players. The incidence of training injuries was prospectively studied in 60 semiprofessional rugby league players over 1 season. Injury data was collected from 72 training sessions, which included all preseason and in-season training sessions. Injuries were described according to site, type, and the training activity performed at the time of injury. The majority of injuries (90.9 per 1000 training hours, 37.5%) were sustained in traditional conditioning activities that involved no skill component (i.e., running without the ball). In contrast, the incidence of injuries sustained while participating in skill-based conditioning games (26.0 per 1000 training hours, 10.7%) was low. These results suggest that skill-based conditioning games offer a safe, effective method of conditioning for rugby league players.     

Eye injuries in squash: a preventable disease.

As more Canadians are taking up squash the incidence of eye injuries is increasing dramatically. Over 2-1/2 years, 23 cases from one urban practice were examined. Almost half of the group required inhospital treatment. Five patients sustained a permanent decrease in vision; these cases involved three corneal scars, one cataract and one macular cyst. Patients wearing glasses or hard contact lenses appear to be more susceptible to serious eye injury. Experience does not appear to reduce the likelihood of eye injuries; the patients in this study had played squash for 5.6 years on the average. Consequently the medical profession must take the lead by encouraging squash players to use protective equipment now available to reduce the incidence of these injuries that pose so much personal hazard.     

Eye injuries in Canadian hockey.

Increasing public concern led the Canadian Ophthalmological Society, in January 1974, to form a committee to study the incidence, types and causes of hockey eye injuries and to devise means of reducing such injuries. Retrospective and current studies were undertaken, and face protectors were tested. In both pilot studies, sticks were the commonest cause and the highest number of eye injuries was in players 11-15 years old. An average of 15% of all injured eyes were rendered legally blind. Cooperation with hockey authorities has resulted in changed rules and their sticter enforcement, and formulation of standards for face protection approved by the Canadian Standards Association. In this interim report the committee recommends that all amateur hockey players wear eye protectors and urges ophthalmologists to participate in efforts to improve the design of protective equipment.     

Squash ball to eye ball: the likelihood of squash players incurring an eye injury.

The records of the 118 patients treated as Southampton Eye Hospital during 1978-9 for injuries incurred while playing squash, badminton, tennis, table tennis, cricket, and football show that for squash the main cause of eye injury was the player being hit by the ball. Severe eye injuries--those requiring treatment as an inpatient--were rare but much more frequent than such injuries in other sports. Less serious injuries--those requiring treatment as an outpatient--were also rare, with a frequency comparable with that of similar injuries in football and badminton. Squash players are most unlikely to incur an eye injury, but should this occur it has far-reaching consequences both in the short and the long term. Each individual player must weigh these chances and consequences against the possible inconvenience of using some form of eye protection.     

Injuries in Rugby Union football.

In a prospective study of 185 players attached to 10 British rugby clubs, 151 injuries were recorded among 98 of them (53%) during a single season. Forwards sustained significantly more injuries than backs. The standard of rugby, players'' body weights, degree of fitness, and presence of joint hypermobility did not affect the risk of injury. The leg was the most common site of injury. Head and neck injuries were significantly more common when play was static and on wet pitches. Scrummaging accounted for no neck injuries. Almost half the injuries occurred during the last quarter of games. Foul play might have caused as many as 47 (31%) of all reported injuries. Complete eradication of deliberately dangerous play would considerably reduce the high incidence of injuries in this sport.     

Bodychecking Rules and Concussion in Elite Hockey

Athletes participating in contact sports such as ice hockey are exposed to a high risk of suffering a concussion. We determined whether recent rule changes regulating contact to the head introduced in 2010–11 and 2011–12 have been effective in reducing the incidence of concussion in the National Hockey League (NHL). A league with a longstanding ban on hits contacting the head, the Ontario Hockey League (OHL), was also studied. A retrospective study of NHL and OHL games for the 2009–10 to 2011–12 seasons was performed using official game records and team injury reports in addition to other media sources. Concussion incidence over the 3 seasons analyzed was 5.23 per 100 NHL regular season games and 5.05 per 100 OHL regular season games (IRR 1.04; 95% CI 1.01, 1.50). When injuries described as concussion-like or suspicious of concussion were included, incidences rose to 8.8 and 7.1 per 100 games respectively (IRR 1.23; 95% CI 0.81, 1.32). The number of NHL concussions or suspected concussions was lower in 2009–10 than in 2010–11 (IRR 0.61; 95% CI 0.45, 0.83), but did not increase from 2010–11 to 2011–12 (IRR 1.05; 95% CI 0.80, 1.38). 64.2% of NHL concussions were caused by bodychecking, and only 28.4% of concussions and 36.8% of suspected concussions were caused by illegal incidents. We conclude that rules regulating bodychecking to the head did not reduce the number of players suffering concussions during NHL regular season play and that further changes or stricter enforcement of existing rules may be required to minimize the risk of players suffering these injuries.     

Prediction of globe rupture caused by primary blast: a finite element analysis

Although a human eye comprises less than 0.1% of the frontal body surface area, injuries to the eye are found to be disproportionally common in survivors of explosions. This study aimed to introduce a Lagrangian–Eulerian coupling model to predict globe rupture resulting from primary blast effect. A finite element model of a human eye was created using Lagrangian mesh. An explosive and its surrounding air domain were modelled using Eulerian mesh. Coupling the two models allowed simulating the blast wave generation, propagation and interaction with the eye. The results showed that the peak overpressures caused by blast wave on the corneal apex are 2080, 932.1 and 487.3 kPa for the victim distances of 0.75, 1.0 and 1.25 m, respectively. Higher stress occurred at the limbus, where the peaks for the three victim distances are 25.5, 14.1 and 6.4 MPa. The overpressure threshold of globe rupture was determined as 2000 kPa in a small-scale explosion. The findings would provide insights into the mechanism of primary blast-induced ocular injuries.     

Serious childhood injuries caused by air guns.

OBJECTIVE: To determine the severity of nonfatal injuries to children caused by air guns and pellet guns. DESIGN: Case series (hospital chart review). SETTING: Inpatient wards of the Children''s Hospital of Eastern Ontario. PATIENTS: All children under 18 years of age admitted to the hospital from Jan. 1, 1979, to Dec. 31, 1989, under ICD code E917, E922, E955, E965, E970 or E985 who had suffered air gun injuries. MAIN OUTCOME MEASURES: Personal data, circumstances of event and clinical data. RESULTS: The 43 children (37 boys) had a median age of 12 years. The circumstances of the accident were known in 20 cases: 17 children were playing and 3 were cleaning the gun when it went off. Four children thought the gun was unloaded. In five cases the bullet ricocheted into the eye. Nine injuries were self-inflicted. Injury was to the extremities in 21 (49%), the eyes in 15 (35%) and the head and neck in 7 (16%). The median length of hospital stay was 4 days. Six children had long-term disabilities, all the result of eye injuries; two had cataract surgery, and four required enucleation of the eye. CONCLUSIONS: Air guns can cause serious injury to children. Their sale needs to be banned or at least carefully regulated.     

Modelling human eye under blast loading

Primary blast injury (PBI) is the general term that refers to injuries resulting from the mere interaction of a blast wave with the body. Although few instances of primary ocular blast injury, without a concomitant secondary blast injury from debris, are documented, some experimental studies demonstrate its occurrence. In order to investigate PBI to the eye, a finite element model of the human eye using simple constitutive models was developed. The material parameters were calibrated by a multi-objective optimisation performed on available eye impact test data. The behaviour of the human eye and the dynamics of mechanisms occurring under PBI loading conditions were modelled. For the generation of the blast waves, different combinations of explosive (trinitrotoluene) mass charge and distance from the eye were analysed. An interpretation of the resulting pressure, based on the propagation and reflection of the waves inside the eye bulb and orbit, is proposed. The peculiar geometry of the bony orbit (similar to a frustum cone) can induce a resonance cavity effect and generate a pressure standing wave potentially hurtful for eye tissues.     

Epidemiology of Pediatric Ocular Trauma in the Chaoshan Region,China, 2001–2010

Background

Ocular trauma is the leading cause of monocular visual disability and noncongenital unilateral blindness in children. This study describes the epidemiology and medical care associated with nonfatal pediatric (≤17 years of age) eye injury-related hospitalization in the largest industrial base for plastic toy production in China.

Methods

A population-based retrospective study of patients hospitalized for ocular and orbital trauma in the ophthalmology departments of 3 major tertiary hospitals from 1st January 2001 to 31st December 2010 was performed.

Results

The study included 1035 injured eyes from 1018 patients over a 10-year period: 560 (54.1%) eyes exhibited open globe injuries, 402 (38.8%) eyes suffered closed globe injuries, 10 (1.0%) eyes suffered chemical injuries and 8 (0.8%) eyes exhibited thermal injuries, representing an average annual hospitalization rate of 0.37 per 10,000 (95% confidence interval [CI], 0.36–0.38) due to pediatric eye injury in the Chaoshan region. The mean patient age was 9.2±4.4 years with a male-to-female ratio of 3.3∶1 (P = 0.007). Children aged 6 to 11 years accounted for the highest percentage (40.8%, 416/1018) of hospitalization, 56.7% (236/416) of whom were hospitalized for open globe wounds. Injury occurred most frequently at home (73.1%). Open globe wounds cost the single most expensive financial burden (60.8%) of total charges with $998±702 mean charges per hospitalization.

Conclusions

Open globe wounds occurred at home are earmarked for the priorities to prevention strategies. Higher public awareness of protecting primary schoolchildren from home-related eye injuries should be strengthened urgently by legislation or regulation since the traditional industrial mode seems to remain the pattern for the foreseeable future. Further research that provide detailed information on the specific inciting agents of pediatric eye injuries are recommended for facilitating the development and targeting of appropriate injury prevention initiatives.     

Decreased expression of antioxidant enzymes in the conjunctival epithelium of dry eye (Sjögren's syndrome) and its possible contribution to the development of ocular surface oxidative injuries

Previous studies have described elevated lipid peroxidase, myeloperoxidase and xanthine oxidoreductase/xanthine oxidase levels on the ocular surface of patients suffering from autoimmune dry eye (Sj?gren's syndrome, SS). Reactive oxygen species generated by various enzymatic systems may be dangerous to the eye if they are not sufficiently cleaved by antioxidants. Because antioxidants have not been investigated in dry eye, the aim of this study was to examine the expression of antioxidant enzymes that cleave reactive oxygen species and play a key role in antioxidant protection. Conjunctival epithelial cells of dry eye (SS) patients were obtained by the method of impression cytology using Millicell membranes. Normal eyes served as controls. In the conjunctival epithelium superoxide dismutase, catalase and glutathione peroxidase were examined immunohistochemically. The enzyme expression levels were determined by image analysis and statistical evaluation. In contrast to normal eyes, where antioxidant enzymes were highly expressed in the conjunctival epithelium, in dry eye their expression was much less pronounced in correlation with the increasing severity of dry eye symptoms. Our study suggests that the decreased expression of antioxidant enzymes in dry eye disease (SS) contributes to the development of anterior eye surface oxidative injuries.     

Under-exposure to official matches is associated with muscle injury incidence in professional footballers

External workload from matches is considered one of the most important muscle injury risk factors for football teams. However, there is scarce published evidence to support this belief. This study examined whether a particular profile of external match workload existed prior to a muscle injury. A total of 144 professional football players belonging to 2 teams were monitored over three seasons. For each muscle injury, a profile of external workload variables was determined for 5 to 8 games and expressed as: time playing exposure, total distance (TD) covered and high-speed running (HSR) covered. In addition, acute:chronic workload ratio (ACWR) was calculated. Sixty players (41.6%) reported a total of 86 muscle injuries during the three seasons. Muscle injuries occurred principally in matches (79.1%), the hamstring being the most affected muscle (44.1%). Injured players displayed substantially lower accumulated exposure time (ES = 0.45), TD (ES = 0.45) and HSR (ES = 0.39) in comparison with uninjured players in the last 5 games prior to injury. Compared to the uninjured players, ACWR for exposure (ES = -0.29/0.02) and running load (ES = -0.24/0.00) did not differ between match 5 and 2 prior to the injury, although uninjured players displayed a substantially greater ACWR in all 3 variables (ES = 0.31/0.35) than injured players in match 1 prior to the injury. Lower playing exposure (minutes played) and associated reduced running distances (TD and HSR) were observed in injured football players. Being under-loaded in official games could be a mediator for muscle injury in this cohort of elite football players.     

A proposed injury threshold for mild traumatic brain injury

Traumatic brain injuries constitute a significant portion of injury resulting from automotive collisions, motorcycle crashes, and sports collisions. Brain injuries not only represent a serious trauma for those involved but also place an enormous burden on society, often exacting a heavy economical, social, and emotional price. Development of intervention strategies to prevent or minimize these injuries requires a complete understanding of injury mechanisms, response and tolerance level. In this study, an attempt is made to delineate actual injury causation and establish a meaningful injury criterion through the use of the actual field accident data. Twenty-four head-to-head field collisions that occurred in professional football games were duplicated using a validated finite element human head model. The injury predictors and injury levels were analyzed based on resulting brain tissue responses and were correlated with the site and occurrence of mild traumatic brain injury (MTBI). Predictions indicated that the shear stress around the brainstem region could be an injury predictor for concussion. Statistical analyses were performed to establish the new brain injury tolerance level.     

The effects of the extraocular muscles on eye impact force–deflection and globe rupture response

There are over 1.9 million eye injuries per year in the United States, with blunt impacts the cause of approximately one-half of all civilian eye injuries. No previous experimental studies have investigated the effects of the extraocular muscles on the impact response of the eye. A spring-powered blunt impactor was used to determine the effects that the extraocular muscles have on the force–deflection and injury response of the eye to blunt trauma. A total of 10 dynamic impact tests were performed at 8.2±0.1 m/s on five human cadaver heads. With the extraocular muscles left intact, the average peak force was found to be 271±51 N at 7.5±0.9 mm posterior translation; with the muscles transected, the average peak force was 268±26 N at 7.6±1.3 mm of posterior translation. From the data available from this study, the peak impact force and overall amount of translation during the impact are not affected by the extraocular muscles. Additionally, from the data presented in this study, the eyes with the extraocular muscles left intact do not rupture with a different injury pattern or display an increased risk for rupture than the eyes with the extraocular muscles transected. Therefore, it is believed that the effect of the extraocular muscles is not sufficient to drastically alter the response of the eye under dynamic impact. This information is useful to characterize the boundary conditions that dictate the eye response from blunt impact and can be used to define the biofidelity requirements for the impact response of synthetic eyes.     

A new model for laser-induced thermal damage in the retina

We describe a new model for laser-induced retinal damage. Our treatment is prompted by the failure of the traditional approach to accurately describe the image size dependence of laser-induced retinal injuries and by a recently reported study which demonstrated that laser injuries to the retina might not appear for up to 48 h post exposure. We propose that at threshold a short-duration, laser-induced, temperature rise melts the membrane of the melanosomes found in the pigmented retinal epithelial cells. This results in the generation of free radicals which initiate a slow chain reaction. If more than a critical number of radicals are generated then cell death may occur at a time much later than the return of the retina to body temperature. We show that the equations consequent upon this mechanism result in a good fit to the recent image size data although more detailed experimental data for rate constants of elementary reactions is still required. This paper contributes to the current understanding of damage mechanisms in the retina and may facilitate the development of new treatments to mitigate laser injuries to the eye. The work will also help minimize the need for further animal experimentation to set laser eye safety standards. Unemployed; no address available.     

The Hammer and the Eye: Beware

In reporting this small series of foreign-body injuries to the eye it is emphasized how normal an eye may appear and yet have a foreign body lurking in its anterior chamber. The patient''s account of the injury may be very deceptive and an x-ray picture of the eye must be taken if a foreign body is even remotely suspected, particularly if a hammer is mentioned. Prompt diagnosis followed by well executed surgery leads to good results in these cases.     

Speaking and Listening with the Eyes: Gaze Signaling during Dyadic Interactions

Cognitive scientists have long been interested in the role that eye gaze plays in social interactions. Previous research suggests that gaze acts as a signaling mechanism and can be used to control turn-taking behaviour. However, early research on this topic employed methods of analysis that aggregated gaze information across an entire trial (or trials), which masks any temporal dynamics that may exist in social interactions. More recently, attempts have been made to understand the temporal characteristics of social gaze but little research has been conducted in a natural setting with two interacting participants. The present study combines a temporally sensitive analysis technique with modern eye tracking technology to 1) validate the overall results from earlier aggregated analyses and 2) provide insight into the specific moment-to-moment temporal characteristics of turn-taking behaviour in a natural setting. Dyads played two social guessing games (20 Questions and Heads Up) while their eyes were tracked. Our general results are in line with past aggregated data, and using cross-correlational analysis on the specific gaze and speech signals of both participants we found that 1) speakers end their turn with direct gaze at the listener and 2) the listener in turn begins to speak with averted gaze. Convergent with theoretical models of social interaction, our data suggest that eye gaze can be used to signal both the end and the beginning of a speaking turn during a social interaction. The present study offers insight into the temporal dynamics of live dyadic interactions and also provides a new method of analysis for eye gaze data when temporal relationships are of interest.