Jessica Orchard

Results of 2 Decades of Injury Surveillance and Public Release of Data in the Australian Football League

Background: Injuries are common in all professional football codes (including soccer, rugby league and union, American football, Gaelic football, and Australian football). Purpose: To report the epidemiology of injuries in the Australian Football League (AFL) from 1992-2012 and to identify changes in injury patterns during that period. Study Design: Descriptive epidemiology study. Methods: The AFL commenced surveying injuries in 1992, with all teams and players included since 1996. An injury was defined as “any physical or medical condition that causes a player to miss a match in the regular season or finals (playoffs).” Administrative records of injury payments (which are compulsory as part of salary cap compliance) to players who do not play matches determined the occurrence of an injury. The seasonal incidence was measured in units of new injuries per club (of 40 players) per season (of 22 matches). Results: There were 4492 players listed over the 21-year period who suffered 13,606 new injuries/illnesses and 1965 recurrent injuries/illnesses, which caused 51,919 matches to be missed. The lowest seasonal incidence was 30.3 new injuries per club per season recorded in 1993, and the highest was 40.3 recorded in 1998. The injury prevalence (missed matches through injury per club per season) varied from a low of 116.3 in 1994 to a high of 157.1 in 2011. The recurrence rate of injuries was highest at 25% in 1992 and lowest at 9% in 2012 and has steadily fallen across the 21 years (P < .01). The most frequent and prevalent injury was hamstring strain (average of 6 injuries per club per season, resulting in 20 missed matches per club per season; recurrence rate, 26%), although the rate of hamstring injuries has fallen in the past 2 seasons after a change to the structure of the interchange bench (P < .05). The rate of knee posterior cruciate ligament injuries fell in the years after a rule change to prevent knee-to-knee collisions in ruckmen (P < .01). Conclusion: Annual public reporting (by way of media release and reports available freely online) of injury rates, using units easily understood by laypeople, has been well received. It has also paved the way for rule changes with the primary goal of improving player safety.

Systematic review: annual incidence of ACL injury and surgery in various populations.

Accurate documentation of injury incidence is critical for study of injury risk factors and prevention. Comparisons of published incidences of anterior cruciate ligament (ACL) injuries and surgical reconstructions are difficult, however, because of the variations in units. Some studies report absolute time-based denominators (such as annual incidence or incidence per 100,000 person years), whereas others report exposure-based denominators (such as incidence per 1,000 player hours or athlete exposures). We converted exposure-based units into annual incidences to compare various studies. National population studies show annual incidence rates of up to 0.05% per person per year in Australia. Professional athletes in basketball, soccer, and the other football codes report an annual incidence of 0.15%–3.7% in studies with at least a moderate sample size. Annual ACL incidence in amateur sporting groups was generally higher than the entire population but lower than among professional athletes. Converting incidence rates to annual units allowed better comparisons to be made between population rates across different studies.

Cricket fast bowling workload patterns as risk factors for tendon, muscle, bone and joint injuries

Objective To assess workload-related risk factors for injuries to particular tissue types in cricket fast bowlers. Design 235 fast bowlers who bowled in 14600 player innings over a period of 15 years were followed in a prospective cohort risk factor study to compare overs bowled in each match (including preceding workload patterns) and injury risk in the 3–4 weeks subsequent to the match. Injuries were categorised according to the affected tissue type as either: bone stress, tendon injuries, muscle strain or joint injuries. Workload risk factors were examined using binomial logistic regression multivariate analysis, with a forward stepwise procedure requiring a significance of <0.05. Results High acute match workload and high previous season workload were risk factors for tendon injuries, but high medium term (3-month workload) was protective. For bone stress injuries, high medium term workload and low career workload were risk factors. For joint injuries, high previous season and career workload were risk factors. There was little relationship between muscle injury and workload although high previous season workload was slightly protective. Conclusions The level of injury risk for some tissue types varies in response to preceding fast bowling workload, with tendon injuries most affected by workload patterns. Workload planning may need to be individualised, depending on individual susceptibility to various injury types. This study supports the theory that tendons are at lowest risk with consistent workloads and susceptible to injury with sudden upgrades in workload. Gradual upgrades are recommended, particularly at the start of a bowlers career to reduce the risk of bone stress injury.

Relationship between interchange usage and risk of hamstring injuries in the Australian Football League

OBJECTIVES To study risk factors for hamstring injury in the Australian Football League (AFL), in particular the effect of recent changes in match participation (increased use of the interchange bench) on hamstring injury. DESIGN Analysis of hamstring match injury statistics extracted from an injury database combined with match participation statistics extracted from a player statistics database. METHODS 56,320 player matches in the AFL over the period 2003-2010 were analyzed, in which 416 hamstring injuries occurred. RESULTS In a Generalized Estimating Equation (GEE) analysis accounting for clustering of different teams, significant predictors of hamstring injuries were recent hamstring injury (RR 4.16, 95% CI 3.19-5.43), past history of ACL reconstruction (RR 1.69, 95% CI 1.09-2.60), past history of calf injury (RR 1.58, 95% CI 1.37-1.82), opposition team making 60 or more interchanges during the game (RR 1.38, 95% CI 1.12-1.68) and player having made 7 or more interchanges off the field in the last 3 weeks (protective RR 0.74, 95% CI 0.59-0.93). CONCLUSIONS These findings suggest that regular interchanges protect individual players against hamstring injuries, but increase the risk of hamstring injury for opposition players. These findings can be explained by a model in which both fatigue and average match running speed are risk factors for hamstring injury. A player who returns to the ground after a rest on the interchange bench may himself have some short-term protection against hamstring injury because of the reduced fatigue, but his rested state may contribute to increased average running speed for his direct opponent, increasing the risk of injury for players on the opposition team.

Fast bowling match workloads over 5-26 days and risk of injury in the following month

OBJECTIVES This study examined whether high match fast bowling workloads in the short to medium term were associated with increased bowling injury rates. DESIGN Prospective cohort study. METHODS Over a 15 year period, workload patterns for 235 individual fast bowlers during time periods from 5 to 26 days were examined to consider whether there was an increased injury rate during the month (28 days) subsequent to the workload. RESULTS Fast bowlers who bowled more than 50 match overs in a 5 day period had a significant increase in injury over the next month compared to bowlers who bowled 50 overs or less RR 1.54 (95% CI 1.04-2.29). For periods ranging from 12 to 26 days, there was no statistically-significant increase in injury over the next month from exceeding thresholds of certain amounts of overs, although bowlers who bowled more than 100 overs in 17 days had a non-significant increase in injury over the next month RR 1.78 (95% CI 0.90-3.50). CONCLUSION There were no statistically-significant increases in subsequent injury risk for high workloads for periods of 12-26 days, although exceeding 100 overs in 17 days (or less) was associated with higher injury rates. Compression of cricket fixtures is likely to have only a minimal contribution to increased fast bowling injury rates being seen in the T20 era (along with sudden workload increases due to transferring between forms of the game, which has been previously established as a major contributor).

Comparison of injury incidences between football teams playing in different climatic regions

Australian Football League (AFL) teams in northern (warmer) areas generally have higher rates of injury than those in southern (cooler) areas. Conversely, in soccer (football) in Europe, teams in northern (cooler) areas have higher rates of injury than those in southern (warmer) areas, with an exception being knee anterior cruciate ligament (ACL) injuries, which are more common in the southern (warmer) parts of Europe. This study examined relative injury incidence in the AFL comparing 9,477 injuries over 229,827 player-weeks from 1999–2012. There was a slightly higher injury incidence for teams from warmer parts of Australia (relative risk [RR] 1.05, 95% confidence interval [CI] 1.01–1.10) with quadriceps strains (RR 1.32, 95% CI 1.10–1.58), knee cartilage injuries (RR 1.42, 95% CI 1.16–1.74), and ankle sprains (RR 1.17, 95% CI 1.00–1.37) all being more likely in warmer region teams. Achilles injuries followed a reverse pattern, tending to be more common in cooler region teams (RR 0.70, 95% CI 0.47–1.03). In conclusion, common findings from the AFL and European soccer are that ankle sprains and ACL injuries are generally more likely in teams playing in warmer climate zones, whereas Achilles tendinopathy may be more likely in teams playing in cooler zones. These injuries may have climate or surface risk factors (possibly related to types and structure of grass and shoe-surface traction) that are universal across different football codes.

Screening for atrial fibrillation during influenza vaccinations by primary care nurses using a smartphone electrocardiograph (iECG): A feasibility study:

Background People with unknown atrial fibrillation (AF), who are often asymptomatic, have a substantially increased risk of stroke. Although recommended in European guidelines, AF screening is not routinely performed. Screening at the time of influenza vaccination presents an ideal opportunity to detect AF in large numbers in a primary care medical setting, with an existing annual recall system for patients aged ≥65 years. Design Cross-sectional pilot study of handheld smartphone electrocardiogram (iECG) screening to identify unknown AF. Methods General practices in Sydney, Australia, were recruited during the influenza-vaccination period of April–June 2015. Practice nurses screened patients aged ≥65 years with a 30-second iECG, which has a validated algorithm for detecting AF in real time. In order to confirm the accuracy of the algorithm, two research cardiologists reviewed de-identified iECGs. In order to explore barriers and enablers, semi-structured interviews were conducted with selected nurses, practice managers and general practitioners. Results Five general practices were recruited, and 973/2476 (39%) patients attending influenza vaccination were screened. Screening took an average of 5 minutes (range 1.5–10 minutes); however, abnormal iECGs required additional time. Newly identified AF was found in 8/973 patients (0.8%). The sensitivity of the iECG automated algorithm was 95% (95% confidence interval: 83–99%) and the specificity was 99% (95% confidence interval: 98–100%). Screening by practice nurses was well accepted by practice staff. Key enablers were the confidence and competence of nurses and a ‘designated champion’ to lead screening at the practice. Barriers were practice specific, and mainly related to staff time and funding. Conclusions Screening with iECG during influenza vaccination by primary care nurses is feasible and well accepted by practice staff. Addressing barriers is likely to increase uptake.

Self-monitoring for atrial fibrillation recurrence in the discharge period post-cardiac surgery using an iPhone electrocardiogram.

OBJECTIVES Postoperative atrial fibrillation (POAF) occurs in 25-40% of patients following cardiac surgery, and is associated with a significant increased risk of stroke and mortality. Routine surveillance is not performed post-discharge; however, recurrence of POAF can occur in up to 30% of patients discharged in sinus rhythm. This study aimed to determine the feasibility of patients self-monitoring with an iPhone handheld electrocardiogram (iECG) to identify recurrence of POAF in the post-discharge period following cardiac surgery. METHODS Patients with POAF following cardiac surgery were eligible for participation if they had no prior history of atrial fibrillation (AF) and were discharged home in stable sinus rhythm. Participants were provided with an iECG and asked to record a 30-s iECG, four times per day for 4 weeks post-discharge. iECGs were automatically transmitted to a secure server, and reviewed for the presence of AF by the research team and a validated algorithm. All participants also received brief education on AF. RESULTS Forty-two participants completed the intervention (mean age 69 ± 9 years, 80% male). Self-monitoring for POAF recurrence using an iECG was feasible and acceptable, and participants felt empowered. Self-monitoring identified 24% (95% confidence interval, 12-39%) with an AF recurrence within 17 days of hospital discharge. These participants were significantly younger than those without AF recurrence (64 ± 7 vs 70 ± 10 years; P = 0.025), and had a significantly lower CHA2DS2-VASc score (2.3 ± 1.2 vs 3.7 ± 2.3; P = 0.007). However, 80% were at high enough stroke risk to warrant consideration of anticoagulation, i.e. CHA2DS2-VASc score ≥2. Only 30% of recurrences were associated with palpitations. Participation also improved AF knowledge from 6.4 ± 1.8 to 7.3 ± 1.8 (P = 0.02), of a total score of 10. CONCLUSIONS Providing patients with an iECG is a non-invasive, inexpensive, convenient and feasible way to monitor for AF recurrence in post-cardiac surgery patients. It also provides a mechanism to provide knowledge about the condition and also potentially reduce anxiety. The success of patients using this technology also has implications for extending the use of iECG self-monitoring to other patient groups such as those undergoing antiarrhythmic interventions for AF.

To Screen or Not to Screen? Examining the Arguments Against Screening for Atrial Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia, with a lifetime risk of one in four of developing AF over the age of 40 years. Around 40% of patients are asymptomatic, which is of concern as AF is a major risk factor for stroke. Early detection and appropriate management reduces stroke risk by two-thirds. Atrial fibrillation screening is now recommended in international guidelines, but there are some common arguments against screening. Overall, to be of value any screening program must fulfil the World Health Organization (WHO) Wilson and Jungner criteria for screening programs. In this paper we address the common arguments, and determine if AF screening fulfils the WHO criteria.

Choice of Health Options In prevention of Cardiovascular Events for people with Atrial Fibrillation (CHOICE-AF): A pilot study

Background: Atrial fibrillation (AF), the most common cardiac arrhythmia, is associated with high risk of stroke and significant health burden. Recent emerging evidence suggests that modifying risk factor profiles of people with AF may assist to reduce stroke risk and health burden. Aims: The purpose of this study was to test the feasibility of a brief telephone-based program targeted at improving cardiovascular risk, and health-related quality of life (HRQoL) in patients with AF Methods: This was a pilot study of a brief three-month telephone-based intervention for patients with diagnosed AF. During an initial face-to-face consultation participants were assisted to set individualized risk factor reduction goals and a treatment plan. Participants received phone-based follow-up for three months, with final assessment at three months. Results: Nineteen participants with AF were recruited, with age range 35–82 years (mean 65±13 years) and 53% were male. No changes were observed in either body mass index (BMI) or waist circumference measures. Participation was associated with significant improvement in reported symptom severity (p=0.005). There were non-significant improvements in physical activity, sedentary behavior, HRQoL, anxiety and depression. Conclusions: Participation in the CHOICE-AF pilot study did not improve BMI or waist circumference: however, it was associated with significant improvement in reported symptom severity. Further research is required to determine the most appropriate model of care for addressing risk factor management for people with AF.