Anterior Cruciate Ligament Rehabilitation for the 10- to 18-Year-Old Adolescent Athlete: Practice Guidelines Based on International Delphi Consensus.

Background: There are 2 treatment options for adolescent athletes with anterior cruciate ligament (ACL) injuries-rehabilitation alone (nonsurgical treatment) or ACL reconstruction plus rehabilitation. However, there is no clear consensus on how to include strength and neuromuscular training during each phase of rehabilitation. Purpose: To develop a practical consensus for adolescent ACL rehabilitation to help provide care to this age group using an international Delphi panel. Study Design: Consensus statement. Methods: A 3-round online international Delphi consensus study was conducted. A mix of open and closed literature-based statements were formulated and sent out to an international panel of 20 ACL rehabilitation experts. Statements were divided into 3 domains as follows: (1) nonsurgical rehabilitation; (2) prehabilitation; and (3) postoperative rehabilitation. Consensus was defined as 70% agreement between panel members. Results: Panel members agreed that rehabilitation should consist of 3 criterion-based phases, with continued injury prevention serving as a fourth phase. They also reached a consensus on rehabilitation being different for 10- to 16-year-olds compared with 17- and 18-year-olds, with a need to distinguish between prepubertal (Tanner stage 1) and mid- to postpubertal (Tanner stages 2-5) athletes. The panel members reached a consensus on the following topics: educational topics during rehabilitation; psychological interventions during rehabilitation; additional consultation of the orthopaedic surgeon; duration of postoperative rehabilitation; exercises during phase 1 of nonsurgical and postoperative rehabilitation; criteria for progression from phase 1 to phase 2; resistance training during phase 2; jumping exercises during phase 2; criteria for progression from phase 2 to phase 3; and criteria for return to sports (RTS). The most notable differences in recommendations for prepubertal compared with mid- to postpubertal athletes were described for resistance training and RTS criteria. Conclusion: Together with available evidence, this international Delphi statement provides a framework based on expert consensus and describes a practice guideline for adolescent ACL rehabilitation, which can be used in day-to-day practice. This is an important step toward reducing practice inconsistencies, improving the quality of rehabilitation after adolescent ACL injuries, and closing the evidence-practice gap while waiting for further studies to provide clarity.

Development of a Standardised System to Classify Injury-Inciting Circumstances in Football: the Football Injury Inciting Circumstances Classification System (FIICCS).

BACKGROUND: A comprehensive examination of the sport-specific activities and circumstances being performed at the time of injury is important to hypothesise mechanisms, develop prevention strategies and inform future investigations. Results reported in the literature are inconsistent because inciting activities are reported using different classifications. Hence the aim was to develop a standardised system for the reporting of inciting circumstances. METHODS: The system was developed using a modified Nominal Group Technique. The initial panel included 12 sports practitioners and researchers from four continents with respectively ≥ 5 years of experience working in professional football and/or conducting injury research. The process consisted of six phases: idea generation, two surveys, one online meeting and two confirmations. For answers to the closed questions, consensus was deemed achieved if ≥ 70% of respondents agreed. Open-ended answers were qualitatively analysed and then introduced in subsequent phases. RESULTS: Ten panellists completed the study. The risk of attrition bias was low. The developed system includes a comprehensive range of inciting circumstances across five domains: contact type, ball situation, physical activity, session details, contextual information. The system also distinguishes between a core set (essential reporting) and an optional set. The panel deemed all the domains to be important and easy to use both in football and in research environments. CONCLUSION: A system to classify inciting circumstances in football was developed. Given the extent of reporting inconsistency of inciting circumstances in the available literature, this can be used while further studies evaluate its reliability.

Injury incidence and burden differ between season phases in male academy football (soccer) players.

Adolescent elite-level footballers are exposed to unique physical and psychological stressors which may increase injury risk, with fluctuating injury prevalence and burden. This study investigates the patterns of injury incidence and burden from 2017 to 2020 within combined pre-, start-of-, mid- and end-of-season and school-holiday phases in U13-U18 Australian male academy players. Injury incidence rate and burden were calculated for medical attention (MA), full and partial time-loss (TL) and non-time-loss (non-TL) injuries. Injury rate ratios (IRR) for injury incidences were assessed using Generalised Linear Mixed Models, and 99% confidence intervals for injury burden differences between phases. MA and non-TL injury incidence rates were higher during pre-season (IRR 1.65, p = 0.01; IRR 2.08, p = 0.02, respectively), and mid-season showed a higher non-TL incidence rate (IRR 2.15, p = 0.02) and burden (69 days with injury/1000 hrs, CI 47-103) compared to end-of-season (25 days with injury/1000 hrs, CI 15-45). MA injury rates and partial TL injury burden were higher during school compared to holiday periods (IRR 0.6, p = 0.04; 61 partial days lost/1000 hrs, CI 35-104; 13 partial days lost/1000 hrs, CI 8-23). Season phase and return-to-school may increase injury risks for elite academy footballers, and considering these phases may assist in developing injury prevention systems.

Exploring the true burden of a time-loss injury: full vs partial time-loss in elite academy football (soccer).

In football, the number of days without full participation in training/competition is often used as a surrogate measure for time-loss (TL) caused by injury. However, injury management and return-to-play processes frequently include modified participation, which to date has only been recorded through self-reports. This study aims to demonstrate the differentiation between 'full' (no participation in team football) and 'partial' (reduced/modified participation in team football) burden. Injury and exposure data were collected from 118 male elite footballers (U13-U18) over 3 consecutive seasons according to the Football Consensus Statement. TL injury burden was calculated separately as the number of total, 'full' and 'partial' days lost per 1000 h of exposure. Injury burden (137.2 days lost/1000 h, 95% CI 133.4-141.0) was comprised of 23% (31.9 days lost/1000 h, 95% CI 30.1-33.8) partial TL and 77% (105.3 days lost/1000 h, 95% CI 102.0-108.6) full TL burden. Injuries of moderate severity (8-28 days lost) showed 40% of partial TL. TL injury incidence rate (6.6 injuries/1000 h, 95% CI 5.8-7.5), the number of severe injuries (16%), and the distribution of TL and non-TL injuries (56% and 44%) were comparable to other reports in elite youth footballers. Almost one-quarter of the TL injury burden showed that injured players were still included in some team football activities, which, for injuries with TL >7 days, was likely related to the return to play process. Therefore, reporting on partial TL provides insight into the true impact of injury on participation levels.

Epidemiology of gradual-onset knee injuries in team ball-sports: A systematic review with meta-analysis of prevalence, incidence, and burden by sex, sport, age, and participation level.

OBJECTIVES: To systematically evaluate the literature and estimate the prevalence, incidence, and burden of gradual-onset knee injuries in team ball-sports. DESIGN: Systematic review with meta-analysis. METHODS: Six databases (MEDLINE, EMBASE, Web of Science, CINAHL, SPORTDiscus, SCOPUS) were searched from inception to June 2021. Cohort studies of team ball-sports reporting the number of gradual-onset knee injuries were included. Study quality was assessed using a modified Newcastle-Ottawa scale. Studies were pooled using a Freeman-Tukey Double arcsine transformation (prevalence) and a Poisson random effects regression model (incidence, burden). RESULTS: Forty-nine studies that captured gradual-onset knee injuries (unclassified, patellofemoral pain, tendinopathies, and iliotibial band friction syndrome) across 15 team ball-sports were included. For unclassified gradual-onset knee injuries, prevalence was 4 % (95 % Confidence Interval (CI) 2 % to 7 %, I2 = 96 %), incidence was 0.32 per 1000 player-hours (95 % CI 0.25 to 0.43, I2 = 88 %), and burden was 3.24 days lost per 1000 player-hours (95 % CI 1.95 to 5.37, I2 = 99 %). For patellofemoral pain, prevalence was 6 % (95 % CI 1 % to 13 %, I2 = 93 %), and incidence was 0.07 per 1000 player-hours (95 % CI 0.04 to 0.12, I2 = 67 %). For tendinopathies, prevalence was 1 % (95 % CI 0 % to 2 %, I2 = 68 %), incidence was 0.07 per 1000 player-hours (95 % CI 0.04 to 0.11, I2 = 76 %), and burden was 2.14 days lost per 1000 player-hours (95 % CI 1.23 to 3.71, I2 = 92 %). CONCLUSIONS: Estimates of prevalence, incidence and burden generated from this systematic review quantify the extent of gradual-onset knee injuries in team ball-sports. Further research is required to assess whether age, sport, and participation level are predictors of gradual-onset knee injuries.

Non-contact Anterior Cruciate Ligament Injury Epidemiology in Team-Ball Sports: A Systematic Review with Meta-analysis by Sex, Age, Sport, Participation Level, and Exposure Type.

BACKGROUND: Not all anterior cruciate ligament (ACL) injuries are preventable. While some ACL injuries are unavoidable such as those resulting from a tackle, others that occur in non-contact situations like twisting and turning in the absence of external contact might be more preventable. Because ACL injuries commonly occur in team ball-sports that involve jumping, landing and cutting manoeuvres, accurate information about the epidemiology of non-contact ACL injuries in these sports is needed to quantify their extent and burden to guide resource allocation for risk-reduction efforts. OBJECTIVE: To synthesize the evidence on the incidence and proportion of non-contact to total ACL injuries by sex, age, sport, participation level and exposure type in team ball-sports. METHODS: Six databases (MEDLINE, EMBASE, Web of Science, CINAHL, Scopus and SPORTDiscus) were searched from inception to July 2021. Cohort studies of team ball-sports reporting number of knee injuries as a function of exposure and injury mechanism were included. RESULTS: Forty-five studies covering 13 team ball-sports were included. The overall proportion of non-contact to total ACL injuries was 55% (95% CI 48-62, I2 = 82%; females: 63%, 95% CI 53-71, I2 = 84%; males: 50%, 95% CI 42-58, I2 = 86%). The overall incidence of non-contact ACL injuries was 0.07 per 1000 player-hours (95% CI 0.05-0.10, I2 = 77%), and 0.05 per 1000 player-exposures (95% CI 0.03-0.07, I2 = 97%). Injury incidence was higher in female athletes (0.14 per 1000 player-hours, 95% CI 0.10-0.19, I2 = 40%) than male athletes (0.05 per 1000 player-hours, 95% CI 0.03-0.07, I2 = 48%), and this difference was significant. Injury incidence during competition was higher (0.48 per 1000 player-hours, 95% CI 0.32-0.72, I2 = 77%; 0.32 per 1000 player-exposures, 95% CI 0.15-0.70, I2 = 96%) than during training (0.04 per 1000 player-hours, 95% CI 0.02-0.07, I2 = 63%; 0.02 per 1000 player-exposures, 95% CI 0.01-0.05, I2 = 86%) and these differences were significant. Heterogeneity across studies was generally high. CONCLUSION: This study quantifies several key epidemiological findings for ACL injuries in team ball-sports. Non-contact ACL injuries represented over half of all ACL injuries sustained. The proportion of non-contact to total ACL injuries and injury incidence were higher in female than in male athletes. Injuries mostly occurred in competition settings.

Part 2 of the 11+ as an effective home-based exercise programme in elite academy football (soccer) players: a one-club matched-paired randomised controlled trial.

Background:Although the 11+ is known to reduce injuries and improve performance in adolescent footballers, its duration presents a notable barrier to implementation. Hence, this study investigated injury and performance outcomes when 65 elite male academy footballers either performed Part 2 3x/week at training (TG) or at home (HG).Methods:Time to stabilisation (TTS), eccentric hamstring strength (EH-S) and countermovement jump height (CMJ-H) were collected 4 times during the 2019 football season. Linear mixed models were used to evaluate main and interaction effects of group and time. Bonferroni post-hoc tests were used to account for multiple comparisons. Differences in time loss and medical attention injuries were determined using a two-tailed Z test for a comparison of rates.Results:Relative to baseline, EH-S (HG 4.3 kg, 95% CI 3 to 5.7, p < 0.001; TG 5.5 kg, 95% CI 4.3 to 6.6, p < 0.001) and CMJ-H (HG 3.5 cm, 95% CI 2.2 to 4.7, p < 0.001; TG 3.2 cm, 95% CI 2.2 to 4.3, p < 0.001) increased, with no difference between groups observed at the end of the season. All injury outcomes were similar.Conclusion: Rescheduling Part 2 did not affect performance or increased injury risks in academy footballers.

Influence of Training Schedules on Objective Measures of Sleep in Adolescent Academy Football Players.

Brown, GA, Veith, S, Sampson, JA, Whalan, M, and Fullagar, HHK. Influence of training schedules on objective measures of sleep in adolescent academy football players. J Strength Cond Res 34(9): 2515-2521, 2020-Football academy settings may pose risks to adolescent athletes achieving sufficient sleep because of the contextual challenges these players face (e.g., psychosocial pressure, changes in training, competition, and academic stress). Given the importance of sleep to overall health as well as physical athletic development and injury risk, this study aimed to investigate whether differences in training schedules (morning vs. evening training sessions) affected objective measures of sleep in adolescent academy football (soccer) players. Twelve academy players (mean age 14.18 ± 1.36 years) wore an ActiGraph accelerometer on nights before, and nights of, training days in 2 separate weeks where morning (09:00-11:00 hours) and evening (18:00-20:00 hours) training occurred. Objective sleep parameters and training load data were collected. Night-time sleep periods were categorized as sleep preceding morning training, preceding evening training, or after evening training. One-way univariate and multivariate analyses of variance for repeated measures were performed to determine the impact of the training schedule on sleep. Significance levels were set at p < 0.05. The total sleep time was below the recommended guidelines (<8 hours) across conditions. A large significant effect of the training schedule on time attempted to fall asleep (p = 0.004, effect size [ES] = 0.40) and time of sleep (p = 0.003, ES = 0.41) was present, with post-evening sessions resulting in the latest times. Overall, the players' sleep behavior was resilient to changes in training schedules. However, the low sleep durations (and potential risks to physical performance/injury) suggest that sleep education coupled with practical interventions are required in this cohort.

Rescheduling Part 2 of the 11+ reduces injury burden and increases compliance in semi-professional football.

Although the 11+ program has been shown to reduce injuries in sub-elite football, program compliance is typically poor, suggesting that strategies to optimize delivery are necessary. This study investigated the effect of rescheduling Part 2 of the three-part 11+ program on program effectiveness. Twenty-five semi-professional football clubs were randomly allocated to either a Standard-11+ (n = 398 players) or P2post group (n = 408 players). Both groups performed the 11+ program at least twice a week throughout the 2017 football season. The Standard-11+ group performed the entire 11+ program before training activities commenced, whereas the P2post group performed Parts 1 and 3 of the 11+ program before and Part 2 after training. Injuries, exposure, and individual player 11+ dose were monitored throughout the season. No significant between group difference in injury incidence rate (P2pos t vs Standard-11+ = 11.8 vs 12.3 injuries/1000 h) was observed. Severe time loss injuries > 28 days (33 vs 58 injuries; P < .002) and total days lost to injury (4303 vs 5815 days; P < .001) were lower in the P2post group. A higher 11+ program dose was observed in the P2post (29.1 doses; 95% CI 27.9-30.1) versus Standard-11+ group (18.9 doses; 95% CI 17.6-20.2; P < .001). In semi-professional football, rescheduling Part 2 of the 11+ program to the end of training maintained the effectiveness of the original 11+ program to reduce injury incidence. Importantly, rescheduling Part 2 improved player compliance and reduced the number of severe injuries and total injury burden, thereby enhancing effectiveness of the 11+ program.

The incidence and burden of time loss injury in Australian men's sub-elite football (soccer): A single season prospective cohort study.

OBJECTIVES: This study aimed to conduct the first injury surveillance study in sub-elite football in Australia, using methods from the international football consensus statement. DESIGN: Descriptive epidemiological study. METHODS: 1049 sub-elite football players were recruited during the 2016 season. Injury and exposure data was collected by trained Primary Data Collectors (PDCs) who attended every training session and match. RESULTS: There were 1041 time loss injuries recorded during 52,127h of exposure resulting in an injury incidence rate of 20 injuries/1000h (95% Confidence Interval [CI]: 15.9-23.3). The injury burden (days lost to injury relative to exposure) was 228days lost/1000h. Muscle and ligament injuries were the most prevalent (41% and 26%) and incurred the highest injury burden (83 and 80days lost/1000h, respectively). The most common injuries were observed at the thigh (22%) and ankle (17%), with hamstring (13%) the highest reported muscle injury. The profile of injury severity was: mild - 35%; minor - 29%; moderate - 28% and severe - 8%. Recurrent injuries accounted for 20% of all injuries. CONCLUSIONS: By addressing issues identified with injury recording in sub-elite football, this study found that the injury incidence was twice that observed in previous research in elite and sub-elite football cohorts. Injury burden was also twice that of the elite setting, with similar injuries associated with the highest burden. The results highlight the need for investment into medical provision, facilities, coach education and injury mitigation programmes to reduce healthcare costs to sub-elite players in Australia.

Soccer Injury Movement Screen (SIMS) Composite Score Is Not Associated With Injury Among Semiprofessional Soccer Players.

Background The association between movement quality and injury is equivocal. No soccer-specific movement assessment has been prospectively investigated in relation to injury risk. Objectives To investigate the association between a soccer-specific movement-quality assessment and injury risk among semiprofessional soccer players. Methods In this prospective cohort study, semiprofessional soccer players (n = 306) from 12 clubs completed the Soccer Injury Movement Screen (SIMS) during the preseason period. Individual training/match exposure and noncontact time-loss injuries were recorded prospectively for the entirety of the 2016 season. Relative risks were calculated, and presented with 90% confidence intervals, for the SIMS composite and individual subtest scores from generalized linear models with Poisson distribution offset for exposure. Results When considering noncontact time-loss lower extremity injuries (primary level of analysis), there was a most likely trivial association with the SIMS composite score. Similarly, the SIMS composite score demonstrated most likely to likely trivial associations with all injury categories included in the secondary level of analysis (noncontact time-loss hip/groin, thigh, knee, and ankle injuries). When considering hamstring strains and ankle sprains specifically (tertiary level of analysis), the SIMS composite score demonstrated very likely trivial associations. A total of 262 noncontact time-loss injuries were recorded. The overall (training and match exposure combined) incidence of noncontact time-loss injury was 12/1000 hours. Conclusion The SIMS composite score demonstrated no association with any of the investigated categories of soccer-related injury. The SIMS composite score should not be used to group players into high- or low-risk groups. Level of Evidence Prognosis, level 4. J Orthop Sports Phys Ther 2018;48(8):630-636. Epub 8 May 2018. doi:10.2519/jospt.2018.8037.