Nordic strength and history of hamstring injury in Australian Football League players

ObjectivesCompare hamstring strength between Australian Football League (AFL) players with and without a prior hamstring injury and determine the effect of the number of previous hamstring injuries, time since the last injury, and injury severity, on hamstring strength.DesignCross-sectional, retrospective.SettingAFL clubs.Participants124 AFL players.Main outcome measuresBilateral hamstring strength was assessed on a Nordbord (Vald Performance) during the Nordic Hamstring Exercise. Self-reported questionnaires were used to record previous hamstring injuries. Players were categorized into No Injury or Hamstring Injury groups. Previously injured players were subgrouped based on number of prior hamstring injuries (single or multiple), time since the last hamstring injury (≤1 or > 1-year ago), and hamstring injury severity (≤3 or > 3 matches missed).Results19 hamstring injuries were reported. Hamstring strength was not different between players with and without a history of hamstring injury when assessed in absolute (N) or relative (i.e., N.kg⁻¹) terms. No differences in strength were detected between hamstring injury subgroups when assessed in absolute or relative terms.ConclusionsAFL players that experienced a previous hamstring injury did not exhibit deficits in hamstring strength relative to their uninjured limb or players without a previous hamstring injury.     

Epidemiology of injuries in the Australian Football League, seasons 1997-2000

OBJECTIVE: To describe the epidemiology of injuries in the Australian Football League (AFL) over four seasons. METHODS: An injury was defined as "any physical or medical condition that caused a player to miss a match in the regular season." The rationale for this definition was to eliminate a previously noted tendency of team recorders to interpret injury definitions subjectively. Administrative records of injury payments to players who did not play matches determined the occurrence of an injury. RESULTS: The seasonal incidence of new injuries was 39 per club (of 40 players) per season (of 22 matches). The match injury incidence for AFL games was 25.7 injuries per 1000 player hours. The injury prevalence (percentage of players missing through injury in an average week) was 16%. The recurrence rate of injuries was 17%. The most common and prevalent injury was hamstring strain (six injuries per club per season, resulting in 21 missed matches per club per season), followed in prevalence by anterior cruciate ligament and groin injuries. CONCLUSIONS: The injury definition of this study does not produce incidence rates that are complete for all minor injuries. However, the determination of an injury is made by a single entity in exactly the same manner for all teams, which overcomes a significant methodological flaw present in other multiteam injury surveillance systems.     

Intramuscular corticosteroid injection for hamstring injuries. A 13-year experience in the National Football League

The purpose of this study was to assess the safety of intramuscular corticosteroid injection in selected, severe hamstring injuries in professional football players. Clinicians have been reluctant to use corticosteroid injections in or around muscle-tendon units because of concern of incomplete healing or rupture. We retrospectively reviewed the computer database of one National Football League team for all hamstring injuries requiring treatment between January 1985 and January 1998. We found that 431 players had suffered such injury. We developed a clinical grading system to identify hamstring injury severity and to stratify players for treatment. Fifty-eight players (13%) sustained severe, discrete injuries with a palpable defect within the substance of the muscle and were treated with intramuscular injection of corticosteroid and anesthetic. There were no complications related to the injection of corticosteroid. Only nine players (16%) missed any games as a result of their injury. Final examination revealed no strength deficits, normal muscle bulk and tone, and the ability to generate normal power. We believe that the grading system we developed can assist in selection of injury type for injection. Although lack of a control group limits statements of efficacy of injection, our impression is that intramuscular corticosteroid injection hastens players' return to full play and lessens the game and practice time they miss.     

A pilot randomised controlled trial of eccentric exercise to prevent hamstring injuries in community-level Australian Football

Hamstring injuries are the most common injury sustained by Australian Football players. Eccentric training has been proposed as a potential preventative strategy. This pilot randomised controlled trial (RCT) evaluated the effectiveness of a pre-season eccentric training program for preventing hamstring injuries at the community level of Australian Football. Seven amateur clubs (n=220 players) were recruited. Players were randomised within clubs to the intervention (eccentric exercise) or control (stretching) groups and randomisation was stratified according to previous history of hamstring injury. Five exercise sessions were completed over a 12-week period, three during the pre-season and two during the first 6 weeks of the season. Compliance was recorded and players were monitored for the season to collect injury and participation data. There was no difference between the control (n=106) or intervention (n=114) groups with respect to baseline characteristics. Only 46.8% of all players completed at least two program sessions. Compliance was poorest for the intervention group. Intention-to-treat analysis suggested that players in the intervention group were not at reduced risk of hamstring injury (RR 1.2, 95% CI: 0.5, 2.8). When only control and intervention group players who participated in at least the first two sessions were analysed, 4.0% of intervention and 13.2% of control group players sustained a hamstring injury (RR 0.3, 95% CI: 0.1, 1.4; p=0.098). The findings suggest that a simple program of eccentric exercise could reduce the incidence of hamstring injuries in Australian Football but widespread implementation of this program is not likely because of poor compliance.     

Comparison of training activities and game demands in the Australian Football League.

his paper serves as a companion to our recent study of the movement patterns and game activities of players (from five different positions) during matches in the 2000 Australian Football League season. Using lapsed-time video analysis, the same individual players (n= 11) as filmed in matches were also monitored during 21 in-season, main training sessions conducted by their clubs in order to assess the degree to which training activities matched game demands. In general, the training sessions did not involve physical pressure; therefore there were very few contested marks and ground balls or tackles, shepherds and spoils, thereby not matching these game demands. Players typically had more possessions (kicks and handballs) at training than in games. They also spent a greater percentage of total time standing and less time walking at training than in games. Fast-running and sprinting efforts at training were almost all for durations of <6 secs, which matched game demands, as did changes of direction when sprinting, which were almost all in a 0-90 degrees arc. However, across all players filmed, high intensity (fast-running and sprinting) movements were not performed as frequently at training (one every 76 secs) as in games (one every 51 secs). Therefore, while some game demands were adequately replicated at training, others were not closely simulated, suggesting that, after careful interpretation of these results, some improvements in training practices could be made.     

Mechanisms of traumatic injury to the shoulder girdle in the Australian Football League

ObjectiveTo investigate mechanisms of shoulder girdle injuries and their impact on players from the Australian Football League (AFL).DesignRetrospective video analysis.MethodsTwo experienced sports physiotherapists (>10 years) examined video footage of shoulder complex injuries that occurred in the 2015 premiership season. Information obtained from video footage included activity prior to injury; mechanism of injury; arm, head and neck position and point of body contact at the time of injury. Player demographics and injury characteristics were obtained from club and media data.ResultsThe most common mechanism of injury was lateral contact (34.6%) followed by hyperflexion/ abduction of the shoulder (19.2%). Glenohumeral joint (GHJ) dislocations and subluxations were the most frequent diagnosis for all mechanisms of injury, and occurred in a variety of shoulder positions. Over 80% of injuries occurred with the arm below 100° of shoulder flexion or abduction. The most common activity prior to injury was ‘ball in dispute’ (34.6%). Lateral contact injuries had the highest overall severity (two-thirds of players missed >3 games) and over 50% of shoulder injuries required surgery. Players missed on average 5.1 season games due to shoulder injury.ConclusionThe lateral contact mechanism was the most common and severe mechanism of shoulder injury. Improved understanding of shoulder girdle injury mechanisms can help guide the use of preventative strategies and injury management programs in elite AFL players.     

Risk factors for hamstring injuries in community level Australian football

Objectives: To identify risk factors for hamstring injury at the community level of Australian football.

Methods: A total of 126 community level Australian football players participated in this prospective cohort study. To provide baseline measurements, they completed a questionnaire and had a musculoskeletal screen during the 2000 preseason. All were monitored over the season. Injury surveillance and exposure data were collected for the full season. Survival analysis was used to identify independent predictors of hamstring injury.

Results: A hamstring injury was the first injury of the season in 20 players (16%). After adjustment for exposure, increasing age and decreased quadriceps flexibility were identified as significant independent predictors of the time to sustaining a hamstring injury. Older age (23 years) was associated with an increased risk of hamstring injury (RR 3.8; 95% confidence interval (CI) 1.1 to 14.0; p = 0.044). Players with increased quadriceps flexibility (as measured by the modified Thomas test) were less likely to sustain a hamstring injury (RR 0.3; 95% CI 0.1 to 0.8; p = 0.022).

Conclusions: The findings of this study can be used in the development of hamstring injury prevention strategies and to identify Australian football players at increased risk of hamstring injury.

     

The prognostic value of the hamstring outcome score to predict the risk of hamstring injuries

ObjectivesHamstring injuries are common among soccer players. The hamstring outcome score (HaOS) might be useful to identify amateur players at risk of hamstring injury. Therefore the aims of this study were: To determine the association between the HaOS and prior and new hamstring injuries in amateur soccer players, and to determine the prognostic value of the HaOS for identifying players with or without previous hamstring injuries at risk of future injury.DesignCohort study.MethodsHaOS scores and information about previous injuries were collected at baseline and new injuries were prospectively registered during a cluster-randomized controlled trial involving 400 amateur soccer players. Analysis of variance and t-tests were used to determine the association between the HaOS and previous and new hamstring injury, respectively. Logistic regression analysis indicated the prognostic value of the HaOS for predicting new hamstring injuries.ResultsAnalysis of data of 356 players indicated that lower HaOS scores were associated with more previous hamstring injuries (F = 17.4; p = 0.000) and that players with lower HaOS scores sustained more new hamstring injuries (T = 3.59, df = 67.23, p = 0.001). With a conventional HaOS score cut-off of 80%, logistic regression models yielded a probability of hamstring injuries of 11%, 18%, and 28% for players with 0,1, or 2 hamstring injuries in the previous season, respectively.ConclusionsThe HaOS is associated with previous and future hamstring injury and might be a useful tool to provide players with insight into their risk of sustaining a new hamstring injury risk when used in combination with previous injuries.     

The Football Association Medical Research Programme: an audit of injuries in professional football--analysis of hamstring injuries

OBJECTIVE: To conduct a detailed analysis of hamstring injuries sustained in English professional football over two competitive seasons. METHODS: Club medical staff at 91 professional football clubs annotated player injuries over two seasons. A specific injury audit questionnaire was used together with a weekly form that documented each clubs' current injury status. RESULTS: Completed injury records for the two competitive seasons were obtained from 87% and 76% of the participating clubs respectively. Hamstring strains accounted for 12% of the total injuries over the two seasons with nearly half (53%) involving the biceps femoris. An average of five hamstring strains per club per season was observed. A total of 13 116 days and 2029 matches were missed because of hamstring strains, giving an average of 90 days and 15 matches missed per club per season. In 57% of cases, the injury occurred during running. Hamstring strains were most often observed during matches (62%) with an increase at the end of each half (p<0.01). Groups of players sustaining higher than expected rates of hamstring injury were Premiership (p<0.01) and outfield players (p<0.01), players of black ethnic origin (p<0.05), and players in the older age groups (p<0.01). Only 5% of hamstring strains underwent some form of diagnostic investigation. The reinjury rate for hamstring injury was 12%. CONCLUSION: Hamstring strains are common in football. In trying to reduce the number of initial and recurrent hamstring strains in football, prevention of initial injury is paramount. If injury does occur, the importance of differential diagnosis followed by the management of all causes of posterior thigh pain is emphasised. Clinical reasoning with treatment based on best available evidence is recommended.     

Prevention and management of osteitis pubis in the Australian Football League: A qualitative analysis

ObjectivesTo examine current practices and develop a set of recommendations for the management of osteitis pubis in the Australian Football League (AFL).DesignA qualitative study using in-depth interviews to gather data and thematic coding to analyze findings.SettingParticipants were interviewed in their workplace or at a convenient meeting point.ParticipantsThirty-six medical and fitness staff from the 16 AFL clubs.ResultsRespondents from all clubs viewed osteitis pubis as an overuse injury and recognized that the key to prevention is balancing pelvic integrity and load. Osteitis pubis was described as the end result of a continuum of groin pathology, and recognition of predisposing factors and early detection were identified as the key elements of optimal management. Management strategies included rest, training modification, cross-training, correction of predisposing factors, physical therapy and a progression back to competition. Most clubs also conduct generic prevention and education programs.ConclusionsOverall, respondents perceived that awareness and management of osteitis pubis is currently at a high level in the AFL. Management of osteitis pubis requires the balancing of pelvic integrity and mechanical load through the pelvis and the early identification of warning signs.     

Association between post-game recovery protocols,physical and perceived recovery,and performance in elite Australian Football League players

ObjectivesTo determine the associations between post-game recovery protocols and physical and perceptual recovery, and game performance in Australian Football League players.DesignA longitudinal quasi-experimental study design was used across a season.MethodsA full squad of 44 footballers was monitored weekly across a 23-game season. Players were required to choose from a number of recovery modalities available immediately post-game. These included floor stretching, pool stretching, bike active recovery, pool active recovery, cold-water immersion, contrast therapy and use of a compression garment. Perceptual measures of recovery were recorded throughout the week and a test of physical performance was conducted two days post-game. Game performance ratings were also recorded. The associations between the post-game recovery protocols chosen and players’ perceived recovery, and physical and game performances were determined by the association rule data-mining strategy.ResultsStatistically significant associations were found between a number of post-game recovery protocols and perceptual recovery. In general, players who chose cold-water immersion, floor stretching, no active recovery (neither bike or pool) and the use of a compression garment post-game, had an increased probability of reporting greater perceptual recovery across the following week, relative to all other permutations of recovery protocols chosen. There were no associations found between post-game recovery protocol combinations and physical recovery. No associations were found between the post-game recovery methods and the next game performance.ConclusionsPerceptual recovery among players was enhanced through the selection of specific combinations of recovery protocols post game. However, no links were found between recovery protocols and physical or game performance measures.