Mikkel Bek Clausen

Effect of specific exercise-based football injury prevention programmes on the overall injury rate in football: a systematic review and meta-analysis of the FIFA 11 and 11+ programmes

Objective To investigate the effect of FIFA injury prevention programmes in football (FIFA 11 and FIFA 11+). Design Systematic review and meta-analysis. Eligibility criteria for selecting studies Randomised controlled trials comparing the FIFA injury prevention programmes with a control (no or sham intervention) among football players. Data sources MEDLINE via PubMed, EMBASE via OVID, CINAHL via Ebsco, Web of Science, SportDiscus and Cochrane Central Register of Controlled Trials, from 2004 to 14 March 2016. Results 6 cluster-randomised controlled trials had assessed the effect of FIFA injury prevention programmes compared with controls on the overall football injury incidence in recreational/subelite football. These studies included 2 specific exercise-based injury prevention programmes: FIFA 11 (2 studies) and FIFA 11+ (4 studies). The primary analysis showed a reduction in the overall injury risk ratio of 0.75 (95% CI 0.57 to 0.98), p=0.04, in favour of the FIFA injury prevention programmes. Secondary analyses revealed that when pooling the 4 studies applying the FIFA 11+ prevention programme, a reduction in the overall injury risk ratio (incidence rate ratio (IRR) 0.61; 95% CI 0.48 to 0.77, p<0.001) was present in favour of the FIFA 11+ prevention programme. No reduction was present when pooling the 2 studies including the FIFA 11 prevention programme (IRR 0.99; 95% CI 0.80 to 1.23, p=0.940). Conclusions An injury-preventing effect of the FIFA injury prevention programmes compared with controls was shown in football. This effect was induced by the FIFA 11+ prevention programme which has a substantial injury-preventing effect by reducing football injuries by 39%, whereas a preventive effect of the FIFA 11 prevention programme could not be documented. Trial registration number PROSPERO CRD42015024120.

High Injury Incidence in Adolescent Female Soccer

Background: Previous studies report varying rates of time-loss injuries in adolescent female soccer, ranging from 2.4 to 5.3 per 1000 athlete-exposures or 2.5 to 3.7 per 1000 hours of exposure. However, these studies collected data using traditional injury reports from coaches or medical staff, with methods that significantly underestimate injury rates compared with players’ self-reports. Purpose: The primary aim was to investigate the injury incidence in adolescent female soccer using self-reports via mobile telephone text messaging. The secondary aim was to explore the association between soccer exposure, playing level, and injury risk. Study Design: Descriptive epidemiology study and cohort study; Level of evidence, 2 and 3. Methods: During a full adolescent female soccer season in Denmark (February-June 2012), a population-based sample of 498 girls aged 15 to 18 years was included in the prospective registration of injuries. All players were enrolled on a team participating in Danish Football Association series. Soccer injuries and exposure were reported weekly by answers to standardized text message questions, followed by individual injury interviews. Soccer exposure and playing levels were chosen a priori as the only independent variables of interest in the risk factor analyses. Injury rates and relative risks were estimated using Poisson regression. Generalized estimation equations were used to take into account that players were clustered within teams. Results: There were 498 players who sustained a total of 424 soccer injuries. The incidence of injuries was 15.3 (95% CI, 13.1-17.8), the incidence of time-loss injuries was 9.7 (95% CI, 8.2-11.4), and the incidence of severe injuries was 1.1 (95% CI, 0.7-1.6) per 1000 hours of soccer exposure. Higher average exposure in injury-free weeks was associated with a lower injury risk (P value for trend <.001), and players with low exposure (≤1 h/wk) were 3 to 10 times more likely to sustain a time-loss injury compared with other players (P < .01). Playing level was not associated with the risk of time-loss injuries (P = .18). Conclusion: The injury incidence in adolescent female soccer is high, and this includes many severe injuries. Players with low soccer participation (≤1 h/wk) have a significantly higher injury risk compared with players participating more frequently.

High Risk of Bias and Low Transparency in “How Effective are F-MARC Injury Prevention Programs for Soccer Players? A Systematic Review and Meta-Analysis”

We have read with great interest and attention the paper entitled ‘‘How effective are F-MARC injury prevention programs for soccer players? A systematic review and meta-analysis’’ published in Sports Medicine [1]; however, we are somewhat surprised that it has been accepted for publication as it fails to meet basic requirements for reporting of systematic reviews as described in the Preferred reporting items for systematic reviews and metaanalyses (PRISMA) statement [2]. It appears to be a different analysis from a previous protocol by the same authors entitled ‘‘Meta-analysis on efficacy of the ‘‘FIFA 11?’’ injury prevention program in athletes’’, first registered on 29 September 2014 and revised on 14 October 2014 in the International prospective register of systematic reviews (PROSPERO), but not referred to in the published article [1] (see the following link: http://www.crd.york.ac.uk/PROSPERO/display_ record.asp?ID=CRD42014013852). Such a lack of transparency when registering and reporting systematic reviews, including meta-analyses, is problematic as it increases the possibility for research waste as individual groups may unknowingly end up performing identical systematic reviews. Even more importantly, lack of transparency concerning registration of preplanned analyses in a systematic review with meta-analyses leaves readers, caregivers, and decision makers with no documentation of whether exploratory post hoc data analyses have taken place or not. Without transparent a priori registration it is simply not possible for readers, caregivers, or decision makers to determine whether the reported results in the systematic review should have any practical real-life implication, or should instead be regarded as hypothesis-generating [3]. Furthermore, several methodological issues emerge when thoroughly evaluating the article by Al Attar et al. [1], potentially impacting the injury rate ratio estimates provided by the authors. They combine randomised and non-randomised studies in the same meta-analysis [1], which is in direct opposition to the recommendations of the Cochrane Handbook [3]. Moreover, Al Attar et al. [1] included individuals from a study by Steffen et al. [4] in their meta-analysis, which does not investigate the efficacy of the FIFA 11? programme but merely explores the effect of the FIFA 11? on performance and injury rates in relation to different FIFA 11? delivery methods. Essentially, this means that Al Attar et al. [1] ended up including two groups of individuals in their meta-analysis (one as intervention and one as control) who have performed the exact & Kristian Thorborg kristianthorborg@hotmail.com

Self-reported previous knee injury and low knee function increase knee injury risk in adolescent female football.

Knee injuries are common in adolescent female football. Self‐reported previous knee injury and low Knee injury and Osteoarthritis Outcome Score (KOOS) are proposed to predict future knee injuries, but evidence regarding this in adolescent female football is scarce. The aim of this study was to investigate self‐reported previous knee injury and low KOOS subscale score as risk factors for future knee injuries in adolescent female football. A sample of 326 adolescent female football players, aged 15–18, without knee injury at baseline, were included. Data on self‐reported previous knee injury and KOOS questionnaires were collected at baseline. Time‐loss knee injuries and football exposures were reported weekly by answers to standardized text‐message questions, followed by injury telephone interviews. A priori, self‐reported previous knee injury and low KOOS subscale scores (< 80 points) were chosen as independent variables in the risk factor analyses. The study showed that self‐reported previous knee injury significantly increased the risk of time‐loss knee injury [relative risk (RR): 3.65, 95% confidence (CI) 1.73–7.68; P < 0.001]. Risk of time‐loss knee injury was also significantly increased in players with low KOOS subscale scores (< 80 points) in Activities of Daily Living (RR: 5.0), Sport/Recreational (RR: 2.2) and Quality of Life (RR: 3.0) (P < 0.05). In conclusion, self‐reported previous knee injury and low scores in three KOOS subscales significantly increase the risk of future time‐loss knee injury in adolescent female football.

The Strengthening Exercises in Shoulder Impingement trial (The SExSI-trial) investigating the effectiveness of a simple add-on shoulder strengthening exercise programme in patients with long-lasting subacromial impingement syndrome: Study protocol for a pragmatic, assessor blinded, parallel-group, randomised, controlled trial

BackgroundSubacromial impingement syndrome (SIS) is a painful, and often long lasting, shoulder condition affecting patient function and quality of life. In a recent study, we observed major strength impairments in shoulder external rotation and abduction (~30%) in a population of patients with pronounced and long-lasting SIS. However, the current rehabilitation of such strength impairments may be inadequate, with novel rehabilitation programmes including exercise therapy only improving external rotation strength by 4–13%.As these previous studies are the basis of current practice, this suggests that the strengthening component could be inadequate in the rehabilitation of these patients, and it seems likely that more emphasis should be placed on intensifying this part of the rehabilitation.The purpose of this study is to investigate the effectiveness of a programme consisting of progressive home-based resistance training using an elastic band, aimed at improving shoulder external rotation and abduction strength, added to usual care and initiated shortly after diagnosis has been established.MethodsA pragmatic randomised controlled superiority trial will be conducted, including 200 patients with pronounced and long-lasting SIS, diagnosed using predefined criteria. Participants will be randomised to receive either an add-on intervention of progressive home-based resistance training using an elastic band in addition to usual care or usual care alone in a 1:1 allocation ratio. The randomisation sequence is computer generated, with permuted blocks of random sizes. The primary outcome will be change in Shoulder Pain And Disability Index (SPADI) score from baseline to 16 weeks follow-up. Outcome assessors are blinded to group allocation. Intervention receivers will be kept blind to treatment allocation through minimal information about the content of the add-on intervention and control condition until group allocation is final. Analyses are performed by blinded data analysts.DiscussionIf effective, the simple shoulder strengthening exercise programme investigated in this trial could easily be added to usual care. The usefulness of the trial is further supported by the magnitude of the problem, the information gained from the study and the pragmatism, patient centeredness and transparency of the trial.Trial registrationThe trial is pre-registered at ClinicalTrials.gov with the ID NCT02747251 on April 19, 2016.

Conservative treatment for patients with subacromial impingement: Changes in clinical core outcomes and their relation to specific rehabilitation parameters

Background Impaired patient-reported shoulder function and pain, external-rotation strength, abduction strength, and abduction range-of-motion (ROM) is reported in patients with subacromial impingement (SIS). However, it is unknown how much strength and ROM improves in real-life practice settings with current care. Furthermore, outcomes of treatment might depend on specific rehabilitation parameters, such as the time spent on exercises (exercise-time), number of physiotherapy sessions (physio-sessions) and number of corticosteroid injections, respectively. However, this has not previously been investigated. The purpose of this study was to describe changes in shoulder strength, ROM, patient-reported function and pain, in real-life practice settings, and explore the association between changes in clinical core outcomes and specific rehabilitation parameters. Methods Patients diagnosed with SIS at initial assessment at an outpatient hospital clinic using predefined criteria’s, who had not undergone surgery after 6 months, were included in this prospective cohort study. After initial assessment (baseline), all patients underwent treatment as usual, with no interference from the investigators. The outcomes Shoulder Pain and Disability Index (SPADI:0–100), average pain (NRS:0–10), external rotation strength, abduction strength and abduction ROM, pain during each test (NRS:0–10), were collected at baseline and at six month follow-up. Amount of exercise-time, physio-sessions and steroid-injections was recorded at follow-up. Changes in outcomes were analyzed using Wilcoxon Signed-Rank test, and the corresponding effect sizes (ES) were estimated. The associations between changes in outcomes and rehabilitation parameters were explored using multiple regression analyses. Results Sixty-three patients completed both baseline and follow-up testing. Significant improvements were seen in SPADI (19 points, ES:0.53, p < 0.001) and all pain variables (median 1–1.5 points, ES:0.26–0.39, p < 0.01), but not in strength and ROM (ES:0.9–0.12, p > 0.2). A higher number of physio-sessions was significantly associated with larger improvements in external rotation strength (0.7 Newton/session, p = 0.046), and higher exercise-time was significantly associated with decrease in average pain (−0.2 points/1,000 min, p = 0.048). Discussion Patient-reported function and pain improved after six months of current care, but strength and ROM did not improve. This is interesting, as strengthening exercises is part of most current interventions. While two significant associations were identified between self-reported rehabilitation parameters and outcomes, the small gains per physio-session or 1,000 min of exercise-time reduces the clinical relevance of these relationships. Collectively, the findings from this study indicate room for improvement of the current rehabilitation of SIS, especially with regard to core clinical outcomes, such as strength and range of motion.

Preseason adductor squeeze strength in 303 spanish male soccer athletes: A cross-sectional study

Background: Hip adductor muscle weakness and a history of groin injury both have been identified as strong risk factors for sustaining a new groin injury. Current groin pain and age have been associated with hip adductor strength. These factors could be related, but this has never been investigated. Purpose: To investigate whether soccer athletes with past-season groin pain and with different durations of past-season groin pain had lower preseason hip adductor squeeze strength compared with those without past-season groin pain. We also investigated whether differences in preseason hip adductor squeeze strength in relation to past-season groin pain and duration were influenced by current groin pain and age. Study Design: Cross-sectional study; Level of evidence, 3. Methods: In total, 303 male soccer athletes (mean age, 23 ± 4 years; mean weight, 74.0 ± 7.9 kg; mean height, 178.1 ± 6.3 cm) were included in this study. Self-reported data regarding current groin pain, past-season groin pain, and duration were collected. Hip adductor squeeze strength was obtained using 2 different reliable testing procedures: (1) the short-lever (resistance placed between the knees, feet at the examination bed, and 45° of hip flexion) and (2) the long-lever (resistance placed between the ankles and 0° of hip flexion) squeeze tests. Results: There was no difference between those with (n = 123) and without (n = 180) past-season groin pain for hip adductor squeeze strength when adjusting for current groin pain and age. However, athletes with past-season groin pain lasting longer than 6 weeks (n = 27) showed 11.5% and 15.3% lower values on the short-lever (P = .006) and long-lever (P < .001) hip adductor squeeze strength tests, respectively, compared with those without past-season groin pain. Conclusion: Male soccer athletes with past-season groin pain lasting longer than 6 weeks are likely to begin the next season with a high-risk groin injury profile, including a history of groin pain and hip adduction weakness.

Patients who are candidates for subacromial decompression have more pronounced range of motion deficits, but do not differ in self-reported shoulder function, strength or pain compared to non-candidates

PurposeSubacromial impingement syndrome (SIS) is associated with low self-reported shoulder function, impairments in shoulder strength and range of motion (ROM), and pain. It is not known how the symptomatology associated with SIS is reflected in the choice of treatment. This study compares self-reported shoulder function, shoulder strength, ROM, and pain in patients with SIS considered candidates and non-candidates for subacromial decompression (SAD).MethodSelf-reported shoulder function (Q-DASH and SPADI), maximum isometric muscle strength in shoulder abduction (Abd-strength) and external rotation (ER-strength), active abduction ROM (Abd-ROM) and passive internal rotation ROM (IR-ROM) were measured in a consecutive cohort of patients with SIS referred to an orthopedic outpatient clinic. Additionally, pain during each test and pain levels during the last week were reported. Patients were categorized as candidates or non-candidates for SAD based on their consultation with an orthopedic specialist blinded to test results and self-reported shoulder function. All outcomes and age, gender, weight and duration of symptoms were compared using the unpaired t test or Mann–Whitney’s U test as appropriate.ResultsOne-hundred and fifty-seven patients were included. 25 patients were candidates for SAD, while 132 were not. SAD candidates had significantly lower Abd-ROM (87° vs. 112°, p = 0.011, effect size = 0. 15) and IR-ROM (114° vs. 123°, p = 0.026, effect size = 0.58) additional to higher pain during test of Abd-strength (5.3 vs. 3.7, p = 0.02, effect size = 0.21). No other differences were found between the groups.ConclusionA decrease in abduction and internal rotation range of motion, and increased pain during maximal abduction strength effort are associated with being considered a candidate for subacromial decompression, while self-reported shoulder function, pain during the last week, and rotator cuff strength are not. As SAD candidates primarily differentiates from non-candidates by having more pronounced ROM deficits, it might be important to address ROM in pre- and postsurgical evaluations, but as the overall differences between the two groups seem minor, the relation between impairments and the choice of treatment needs further clarification.Level of evidenceIV.

Inappropriate Methods and Flawed Conclusion in: Can Resistance Training Enhance the Rapid Force Development in Unloaded Dynamic Isoinertial Multijoint Movements? A Systematic Review

Request for Clarification:We have with great interest read the recent article “Can resistance training enhance the rapid force development in unloaded dynamic isoinertial multijoint movements? A systematic review” by van Hooren et al. (10).Although the topic is highly relevant to athletes and staffs

Effects of a lighter, smaller football on Acute match injuries in adolescent female football: A pilot cluster-randomized controlled trial

BACKGROUND The high injury incidence during match-play in female adolescent football is a major concern. In football, males and females play matches with the same football size. No studies have investigated the effect of football size on injury incidence in female adolescent football. Thus, the aim of the present study was to investigate the effects of introducing a lighter, smaller football on the injury pattern in female adolescent football. METHODS We conducted a pilot cluster randomized controlled trial including 26 football teams representing 346 adolescent female football players (age 15-18 years). The teams were randomized to a new lighter, smaller football (INT, N.=12 teams) or a traditional FIFA size 5 football (CON, N.=14 teams) during a full match-season. Acute time-loss injuries and football-exposure during match-play were reported weekly by text-message questions and verified subsequently by telephone interview. RESULTS In total, 46 acute time-loss injuries were registered (5 severe injuries), yielding an incidence rate of 15.2 injuries per 1000 hours of match-play (95% CI: 8.5-27.2) in INT and 18.6 injuries per 1000 hours of match-play (95% CI: 14.0-24.8) in CON. The estimated 22% greater injury incidence rate risk (IRR: 1.22 [95% CI: 0.64-2.35]) in the CON group was not significant. With an IRR of 1.22, a future RCT main study would need to observe 793 acute time-loss injuries during match-play, in order to have a power of 80%. CONCLUSIONS A large-scaled RCT is required to definitively test for beneficial or harmful effects of a lighter, smaller football in adolescent female football.