Risk factors for acute knee injury in female youth football

Purpose

To prospectively evaluate risk factors for acute time-loss knee injury, in particular ACL injury, in female youth football players.

Methods

Risk factors were studied in 4556 players aged 12–17 years from a randomised controlled trial during the 2009 season. Covariates were both intrinsic (body mass index, age, relative age effect, onset of menarche, previous acute knee injury or ACL injury, current knee complaints, and familial disposition of ACL injury) and extrinsic (no. of training sessions/week, no. of matches/week, match exposure ratio, match play with other teams, and artificial turf exposure). Hazard ratios (HRs) and 95 % confidence intervals (CIs) were calculated from individual variable and multiple Cox regression analyses.

Results

Ninety-six acute knee injuries were recorded, 21 of them ACL injuries. Multiple Cox regression showed a fourfold higher ACL injury rate for players with familial disposition of ACL injury (HR 3.57; 95 % CI 1.48–8.62). Significant predictor variables for acute knee injury were age >14 years (HR 1.97; 95 % CI 1.30–2.97), knee complaints at the start of the season (HR 1.98; 95 % CI 1.30–3.02), and familial disposition of ACL injury (HR 1.96; 95 % CI 1.22–3.16). No differences in injury rates were seen when playing on artificial turf compared with natural grass.

Conclusion

Female youth football players with a familial disposition of ACL injury had an increased risk of ACL injury and acute knee injury. Older players and those with knee complaints at pre-season were more at risk of acute knee injury. Although the predictive values were low, these factors could be used in athlete screening to target preventive interventions.

Level of evidence

II.

     

Self-reported psychological characteristics as risk factors for injuries in female youth football

Identifying and understanding injury risk factors are necessary to target the injury-prone athlete and develop injury prevention measurements. The influence of psychological factors on injuries in football is poorly documented. The purpose of this 8-month prospective cohort study therefore was to examine whether psychological player characteristics assessed by a self-administered questionnaire represent risk factors for injury. At baseline, female football players (14–16 years) were asked to complete a detailed questionnaire covering player history, previous injuries, perception of success and motivational climate, life stress, anxiety and coping strategies. During the 2005 season, a total of 1430 players were followed up to record injuries. A history of a previous injury [odds ratio (OR)=1.9 (1.4; 2.5), P <0.001] increased the risk of a new injury to the same region. There were significant differences in disfavor for previously injured compared with non-injured players for ego orientation ( P =0.007), perception of a performance climate ( P =0.003) and experienced stressful life events ( P <0.001). However, only high life stress ( P =0.001) and perception of a mastery climate ( P =0.03) were significant risk factors for new injuries. In conclusion, a perceived mastery climate and a high level of life stress were significant predictors for new injuries in a cohort of young female football players.     

Incidence and risk factors for injury in non-elite netball

This paper identifies the risk and protective factors for injury in non-elite netball. Three-hundred and sixty-eight non-elite netballers completed a baseline questionnaire at the commencement of the 1997 preseason. Participants were telephoned each month during the 1997 and 1998 playing seasons to provide details of their exposure at training and games and any injury experiences in the previous 4 weeks. The incidence of injury in this study was 14 injuries per 1000 player hours. The risk factors for injury were identified as: not warming up before a game (IRR 1.11, 95% CI 1.00-1.23) and not being open to new ideas (IRR 1.04, 95% CI 1.00-1.07). Training for 4 or more hours per week (IRR 0.66, 95% CI 0.45-0.98) and not sustaining an injury in the previous 12 months (IRR 0.58, 95% CI 0.43-0.79) were found to be protective against injury. The risk and protective factors for injury identified in this study can be used as the basis for the development of evidence-based injury prevention strategies that seek to reduce the risk of injury in sport. Injury prevention strategies should focus on the development of effective training programs that include netball-specific skills, activities and movements. Further investigation into the mechanisms associated with the risk and protective factors identified would provide further understanding of why these factors increase or decrease the risk of injury.     

Biological maturity and injury in elite youth football

The purpose of the present study was to investigate injury according to biological maturity in elite under-14 youth football players based at the National Football Institute, France. Over 10 seasons, injury incidence, severity and distribution were compared in 233 players classed according to individual biological maturity determined by skeletal age into three cohorts as early, normal and late maturers.A non-significant higher injury incidence was found in early and normal maturers compared with late maturers. In contrast, the latter group sustained a significantly higher incidence of major injuries compared with early maturers (0.3 vs 0.6 vs 0.9, P=0.039). A significantly higher incidence of osteochrondoses was reported in normal and late maturers (0.3 vs 0.7 vs 0.9, P=0.014), whereas tendinopathy incidence was greater in early and normal maturers (0.06 vs 0.08 vs 0.02, P=0.033). Early maturers incurred the highest incidence of groin strains and re-injuries (P<0.05). There was no significant difference between groups in the seasonal disposition of injury.Biological maturity status did not significantly affect overall injury incidence in elite French youth football players, although there were differences between maturity groups when patterns of injury location, type, severity and re-injury were analyzed.     

Incidence of injury in Texas high school football.

This study was undertaken to determine the incidence of injury in high school football based on evaluation of 100 high schools in the State of Texas during a single football season (1989). Certified athletic trainers were the initial medical professionals providing on-site diagnosis and treatment of all injuries. An injury was defined as: 1) an incident causing an athlete to miss all or part of a single practice or game; 2) any incident treated by a physician; and 3) all head injuries reported to the athletic trainer. Data were collected that allowed calculation of the time of exposure to injury per athlete in the sample. There was 75.5% participation in the study by the certified athletic trainers in the 100 schools. A total of 4399 athletes in varsity football programs participated in the study. There were 2228 injuries, as defined in the study, during the period of study, giving an incidence of injury of 0.506 injury per athlete per year. Severe injuries--those requiring hospitalization--were found in 137 cases, for an incidence rate of 0.031 injury per athlete per year. The incidence of reportable defined injury was calculated to be 0.003 injury per hour of exposure per student athlete. The knee was found to be the most commonly injured anatomic site; the ankle ranked second.     

Coach and player attitudes to injury in youth sport

ObjectivesTo investigate coach and player attitudes to injury in New Zealand (NZ) secondary school sport.DesignCross-sectional surveySettingSecondary school sport.ParticipantsSecondary school coaches and players.Main outcome measuresResponses to a survey of injury attitudes. The survey was distributed in electronic and paper-based form to secondary school coaches and players across three sporting organisations. Coaches’ uptake of injury prevention training and whether they had first aid qualifications was also elicited.Results117 coaches and 226 players from netball, football and basketball participated. The majority of coaches surveyed (n = 82, 70%) reported having a coaching qualification and 72 (62%) had completed a sport related first aid/injury prevention programme. Overall, 196 players (87%) reported hiding an injury to continue playing, and 102 coaches (87%) and 205 players (91%) had witnessed injured players play on. Approximately 50% of players and coaches had seen players put under pressure to play when injured. A lack of knowledge, the desire to win, and not letting the team down were key reasons given for the behaviour reported.ConclusionsThe observed prevalence of players playing on when injured and associated attitudes to secondary school sport injuries demands further investigation.     

Head injuries in the female football player: incidence, mechanisms, risk factors and management

Although all injuries in sports are a concern for participants, head injuries are particularly troublesome because of the potential for long-term cognitive deficits. To prevent any specific injury, it is important to understand the basic frequency and incidence of injury and then the mechanism of injury. Once these are established, prevention programmes can be tested to see if the rate of injury changes. A primary problem with head injuries is recognising that the injury has occurred. Many athletes are not aware of the seriousness of concussive injury, thus this type of injury is probably under-reported. Once the diagnosis of a concussion is made, the next difficult decision is when to return a player to the game. These two management issues dominate the continuing development of understanding of concussive head injury. This paper explores the known gender differences between head injuries and highlights the areas that need to be considered in future research.     

Motor performance is not related to injury risk in growing elite-level male youth football players. A causal inference approach to injury risk assessment

ObjectiveTo identify the causal relation between growth velocity and injury in elite-level youth football players, and to assess the mediating effects of motor performance in this causal pathway.DesignProspective cohort study.MethodsWe measured the body height of 378 male elite-level football players of the U13 to U15 age categories three to four months before and at the start of the competitive season. At the start of the season, players also performed a motor performance test battery, including motor coordination (Körperkoordinationstest für Kinder), muscular performance (standing broad jump, counter movement jump), flexibility (sit and reach), and endurance measures (YoYo intermittent recovery test). Injuries were continuously registered by the academies’ medical staff during the first two months of the season. Based on the causal directed acyclic graph (DAG) that identified our assumptions about causal relations between growth velocity (standardized to cm/y), injuries, and motor performance, the causal effect of growth velocity on injury was obtained by conditioning on maturity offset. We determined the natural indirect effects of growth velocity on injury mediated through motor performance.ResultsIn total, 105 players sustained an injury. Odds ratios (OR) showed a 15% increase in injury risk per centimetre/year of growth velocity (1.15, 95%CI: 1.05–1.26). There was no causal effect of growth on injury through the motor performance mediated pathways (all ORs were close to 1.0 with narrow 95%CIs).ConclusionsGrowth velocity is causally related to injury risk in elite-level youth football players, but motor performance does not mediate this relation.     

Cervical disc herniation in a football player.

A case of cervical disc herniation occurring in close association with playing football is reported. The handling of neck injuries in football players is outlined.     

Obesity in a high school football player.

When a physician disqualifies an athlete based on theoretical deleterious effects, he is doing so based on the perception that the risk of participation is sufficient to override the athlete's desire to participate (4). If sports participation is very important to the athlete, the sports physician should determine what interventions might reduce the risk of participation. Rather than look for reasons for disqualification, the team physician should look for ways for the athlete to participate more safely and reduce the risk of injury. (If the risk of participation is too high, the athlete should be disqualified.) In this case an aggressive shoulder rehabilitation program and prompt follow-up of his asthma and anemia would have been helpful to this athlete's participation in football. In general, team physicians should weigh all the potential risks and benefits in each case and involve the athlete and the family when these difficult playability issues arise. The team physician should be mindful of potential conflicts of interests and should be careful to avoid imposing his or her own values on the athlete. In this case, the disqualification of this athlete based on obesity was not in his best interest. Whether the potential conflicts in decision making played a role in the decision in this case will never be known. Weighing the facts as presented, I believe the athlete's interests would have been better served by allowing him to play after completing a shoulder rehabilitation program.     

Effort thrombosis in an American football player.

A case of lower limb venous thrombosis occurring in a young male after playing American football is described. The features are compared to the more widely recognized effort thrombosis of the upper limb veins. The possibility of effort thrombosis needs to be considered in athletes presenting with leg injuries.     

Cardiovascular risk factors in football players

Cardiovascular disease is a leading cause of death in the United States. Football players represent a subpopulation that may have a unique risk profile pattern. Studies have suggested that football players may be at increased risk for cardiovascular disease. Paradoxically, there may be a cardioprotective effect associated with activity in general and, specifically, participation at higher levels of football. Our review will attempt to outline the pertinent evidence in regards to cardiovascular risk factors in football players. Specifically, hypertension, hypercholesterolemia, obesity, and sedentary lifestyle will be considered. In addition, we will discuss potential risk factors for investigation including C-reactive protein, homocysteine, insulin resistance, and sleep-disordered breathing. Studies at all levels of competition will be considered, including retired players whose findings may represent lifelong changes that occur as a result of participation in football. Further investigation will be needed to help clarify the relationship between football participation and cardiovascular risk.