Balance board training: prevention of traumatic injuries of the lower extremities in female soccer players? A prospective randomized intervention study

Effect of supervision and athlete age and sex on exercise-based injury prevention programme effectiveness in sport: A meta-analysis of 44 studies

We aimed to evaluate the influence of supervision, athlete age and sex and programme duration and adherence on exercise-based injury prevention programme effectiveness in sport. Databases were searched for randomized controlled trials evaluating exercise-based injury prevention programme effectiveness compared to "train-as-normal". A random effects meta-analysis for overall effect and pooled effects by sex and supervision and meta-regression for age, intervention duration and adherence were performed. Programmes were effective overall (risk ratio (RR) 0.71) and equally beneficial for female-only (0.73) and male-only (0.65) cohorts. Supervised programmes were effective (0.67), unlike unsupervised programmes (1.04). No significant association was identified between programme effectiveness and age or intervention duration. The inverse association between injury rate and adherence was significant (β=-0.014, p = 0.004). Supervised programmes reduce injury by 33%, but there is no evidence for the effectiveness of non-supervised programmes. Females and males benefit equally, and age (to early middle age) does not affect programme effectiveness.

Proprioceptive training methods (PTM) in female soccer players - a systematic review

BACKGROUND

Although previous studies have reported that proprioceptive training methods (PTM) have positive effects, there is a relatively small number of studies regarding the impact of PTM in women's soccer. Therefore, there is a need to systematize the given results. In this regard, this systematic review aimed to investigate the effect of proprioceptive training methods in female soccer players.

METHODS

The studies' search and analysis were done according to the PRISMA guidelines. The following databases were checked (Google Scholar, PubMed Cochrane and ProQuest), with additional publication time criteria (2000-2023) using the following keywords: proprioceptive, balance, neuromuscular, training, exercise, intervention, method, activity, female football players, female soccer players, woman soccer players.

RESULTS

A total of 7 studies were included in the quantitative synthesis that meet all the criteria with the number of participants being 2.247. Based on the analysis of the previous research and detailed discussion, the main findings of the study resulted in the partial improvement of explosive strength (66%), strength (50%), muscle imbalance and flexibility (50%) and the prevention and reduction of lower extremity injuries in female soccer players (60%). Only one study reported no significant differences between groups, where rate of major injuries was higher in experimental group.

CONCLUSION

The obtained results indicate the necessity to implement proprioceptive training in female soccer training programs, in order to influence the prevention and reduction of injuries and improve balance, proprioceptive ability and body control.

What exercise programme is the most appropriate to mitigate anterior cruciate ligament injury risk in football (soccer) players? A systematic review and network meta-analysis

OBJECTIVES

To examine the effectiveness of different exercise-based interventions to mitigate the risk of anterior cruciate ligament injury in football players, and to determine which is the most appropriate for them, specifically for female football players.

DESIGN

Four databases were accessed in July 2023 using the keywords football, soccer, athletic injuries, anterior cruciate ligament, knee injuries, injury prevention, exercise-based programme, and risk factor.

METHODS

Randomised controlled trials that evaluated any exercise-based injury prevention intervention compared with a control group on the prevention of anterior cruciate ligament injury in football players were included.

RESULTS

Eleven studies were included. Data were presented as logarithm hazard ratio, credible intervals and standard deviation. FIFA 11+ was the most effective in reducing anterior cruciate ligament injury risk in football players (logarithm hazard ratio = -1.23 [95% credible intervals: -2.20, -0.35]; SD = 0.47), followed by the Knäkontroll programme (logarithm hazard ratio = -0.76 [95% credible intervals: -1.60, -0.03]; standard deviation = 0.42). For females, only Knäkontroll had a significant impact on reducing the risk of anterior cruciate ligament injury (logarithm hazard ratio = -0.62 [95% credible intervals: -1.71, 0.62]; standard deviation = 0.58).

CONCLUSIONS

Our results support the use of FIFA 11+ and Knäkontroll to mitigate injury incidence at overall level. However, the effectiveness of these interventions changed when adjusting for females. Knäkontroll is postulated as the programme with the greatest preventive nature, although these results should be interpreted with caution due to the lack of the sample.

Team Approach: Neuromuscular Training for Primary and Secondary Prevention of Anterior Cruciate Ligament Injury

Neuromuscular training is a method of performance optimization-typically combining plyometrics, balancing training, agility, and dynamic stabilization-predicated on improving the efficiency of fundamental movement patterns. Neuromuscular training has consistently been shown to reduce the risk of anterior cruciate ligament injury, particularly for athletes engaged in activities associated with noncontact knee injuries (i.e., women's soccer). Successful implementation of neuromuscular training programs requires input from coaches, physical therapists, athletic trainers, and physicians to generate efficacious programs with high rates of adherence.

The Effects of Exercise-Based Injury Prevention Programmes on Injury Risk in Adult Recreational Athletes: A Systematic Review and Meta-Analysis

BACKGROUND

Injuries are common in adult recreational athletes. Exercise-based injury prevention programmes offer the potential to reduce the risk of injury and have been a popular research topic. Yet, syntheses and meta-analyses on the effects of exercise-based injury prevention programmes for adult recreational athletes are lacking.

OBJECTIVES

We aimed to synthesise and quantify the pooled intervention effects of exercise-based injury prevention programmes delivered to adults who participate in recreation sports.

METHODS

Studies were eligible for inclusion if they included adult recreational athletes (aged > 16 years), an exercise-based intervention and used a randomised controlled trial design. Exclusion criteria were studies without a control group, studies using a non-randomised design and studies including participants who were undertaking activity mandatory for their occupation. Eleven literature databases were searched from earliest record, up to 9 June, 2022. The Physiotherapy Evidence Database (PEDro) scale was used to assess the risk of bias in all included studies. Reported risk statistics were synthesised in a random-effects meta-analysis to quantify pooled treatment effects and associated 95% confidence intervals and prediction intervals.

RESULTS

Sixteen studies met the criteria. Risk statistics were reported as risk ratios [RRs] (n = 12) or hazard ratios [HRs] (n = 4). Pooled estimates of RRs and HRs were 0.94 (95% confidence interval 0.80-1.09) and 0.65 (95% confidence interval 0.39-1.08), respectively. Prediction intervals were 0.80-1.09 and 0.16-2.70 for RR and HR, respectively. Heterogeneity was very low for RR studies, but high for HR studies (tau = 0.29, I2 = 81%). There was evidence of small study effects for RR studies, evidenced by funnel plot asymmetry and Egger's test for small study bias: - 0.99 (CI - 2.08 to 0.10, p = 0.07).

CONCLUSIONS

Pooled point estimates were suggestive of a reduced risk of injury in intervention groups. Nevertheless, these risk estimates were insufficiently precise, too heterogeneous and potentially compromised by small study effects to arrive at any robust conclusion. More large-scale studies are required to clarify whether exercise-based injury prevention programmes are effective in adult recreational athletes.

CLINICAL TRIAL REGISTRATION

The protocol for this review was prospectively registered in the PROSPERO database (CRD42021232697).

Traumatic muscle injury

Traumatic muscle injury represents a collection of skeletal muscle pathologies caused by trauma to the muscle tissue and is defined as damage to the muscle tissue that can result in a functional deficit. Traumatic muscle injury can affect people across the lifespan and can result from high stresses and strains to skeletal muscle tissue, often due to muscle activation while the muscle is lengthening, resulting in indirect and non-contact muscle injuries (strains or ruptures), or from external impact, resulting in direct muscle injuries (contusion or laceration). At a microscopic level, muscle fibres can repair focal damage but must be completely regenerated after full myofibre necrosis. The diagnosis of muscle injury is based on patient history and physical examination. Imaging may be indicated to eliminate differential diagnoses. The management of muscle injury has changed within the past 5 years from initial rest, immobilization and (over)protection to early activation and progressive loading using an active approach. One challenge of muscle injury management is that numerous medical treatment options, such as medications and injections, are often used or proposed to try to accelerate muscle recovery despite very limited efficacy evidence. Another challenge is the prevention of muscle injury owing to the multifactorial and complex nature of this injury.

The association between foot posture, single leg balance and running biomechanics of the foot

OBJECTIVES

A mal-aligned foot posture (high-arched and flat feet) and poor single leg balance ability have been separately associated with foot injuries during running. Therefore, clinicians assess these routinely. However, the extent to which foot posture and single-leg balance ability affect actual foot biomechanics during running is not known. This study aims to investigate the association of foot posture, single-leg balance ability, and foot biomechanics during running.

METHOD

This is a cross sectional study of sixty-nine participants who had their foot postures and single-leg balance ability assessed. The Foot Posture Index and Balance Error Scoring System were used. Their foot kinetics was measured as they ran on an instrumented treadmill and foot kinematics was processed using a 3D motion capture system. Multiple-regression was used to analyse the variance of foot biomechanics explained by foot posture and single-leg balance ability.

RESULTS

Foot posture and single-leg balance ability were found to account significantly for the variance in rearfoot eversion (24%) and forefoot dorsiflexion (7%). Two regression equations were derived, where rearfoot eversion and forefoot dorsiflexion during running may be predicted.

CONCLUSION

Foot posture and single-leg balance ability can predict rearfoot eversion and forefoot dorsiflexion only during running. Based on the regression equations, individuals with the same foot posture but different single-leg balance ability may exhibit different foot kinematics. However, the angular differences are small. The equations may be useful for clinicians working in places where running gait analysis equipment are not readily accessible. Further studies with larger sample sizes are required to validate these equations. In addition, further studies are necessary to investigate the effect of these two variables under different running conditions e.g. with footwear and with orthoses.

Characteristics and Trends of the Most Cited Knee Surgery, Sports Traumatology, Arthroscopy Articles

Purpose

To compile and analyze the top 50 most frequently cited articles published in the Knee Surgery, Sports Traumatology, Arthroscopy journal.

Methods

Guidelines set by the Preferred Reporting Items for Systematic Reviews were used as the foundation for data collection and analysis. Scopus database was used to acquire the metric analyzed in the study. Once collected, the data was exported to an excel sheet in order to be organized, sorted, and analyzed in accordance with the metrics of interest.

Results

The United States was the most contributory nation with 14 publications, followed by Sweden with13 publications and Germany with eight publications. The most contributory institution was Umeå University in Vasterbottens, Sweden (8) followed by National Institute for Working Life in Stockholm, Sweden (7) and The University of Pittsburgh (5). Most publications were either Level II (19) or Level III (19) in terms of Level of Evidence. There was only one publication that was classified as a Level I paper.

Conclusion

The Journal of Knee Surgery, Sports Traumatology, and Arthroscopy has published very influential research papers as noted by the number of citations amassed by its most popular articles. KSSTA's top cited publications hail largely from major European and United States institutions and are composed of high-quality reports of mostly Level 2 and Level 3 evidence classifications.

Level of Evidence

3.

Combined balance and plyometric training enhances knee function, but not proprioception of elite male badminton players: A pilot randomized controlled study

Objectives

To investigate the effect of combined balance and plyometric training on knee function and proprioception of elite badminton athletes.

Methods

Sixteen elite male badminton players (age: 20.5 ± 1.1 years, height: 177.8 ± 5.1 cm, weight: 68.1 ± 7.2 kg, and training experience: 11.4 ± 1.4 years) volunteered to participate and were randomly assigned to a combined balance and plyometric training (CT) (n = 8) and plyometric (PT) group (n = 8). The CT group performed balance combined with plyometric training three times a week over 6 weeks (40 min of plyometrics and 20 min of balance training); while the PT group undertook only plyometric training for the same period (3-4 sets × 8-12 reps for each exercise). Both groups had the same technical training of badminton.

Results

The knee function and proprioception were assessed at baseline and after the intervention by measuring the performance of single-legged hop tests (LSIO, LSIT, LSIC, LSIS), standing postural sway (COPAP, COPML), and LSI of dominant leg and non-dominant leg. The results showed that as compared to PT, CT induced significantly greater improvements in LSIT and LSIS (p < 0.001) and significant greater percent increase in NAP (p = 0.011). The changes in LSIO, LSIC, DAP, NAP, LSIAP, DML, NML, and LSIML induced by CT did not differ from that induced by PT (p > 0.213).

Conclusion

In elite badminton players, intervention using CT holds great promise to augment the benefits for knee function compared to the intervention using PT only, and at the same time, with at least comparable benefits for proprioception. Future studies are needed to examine and confirm the results of this study.

Preliminary study on acute effects of an intervention to increase dorsiflexion range of motion in reducing medial knee displacement

BACKGROUND

Dynamic knee valgus, visually represented as medial knee displacement, is associated with anterior cruciate ligament injury. Recently, restrictions in ankle dorsiflexion range of motion have been associated with medial knee displacement. Therefore, interventions potentially increasing ankle dorsiflexion range of motion could alleviate medial knee displacement. The purpose of this pilot study was to explore the acute effects of an intervention to increase ankle dorsiflexion range of motion and reduce medial knee displacement in individuals who display medial knee displacement that is corrected with a heel lift.

METHODS

Eight young participants who displayed medial knee displacement corrected with a heel lift completed a single-session intervention aimed at increasing dorsiflexion range of motion. Immediately before and after the intervention session, dorsiflexion range of motion in three static conditions (passive straight-knee, passive bent-knee, and weight-bearing lunge) and medial knee displacement during an overhead squat were assessed.

FINDINGS

The single-session training program increased participants' dorsiflexion range of motion in all three static conditions (p = 0.0005 for straight-knee, 0.02 for bent-knee, and 0.01 for lunge) with moderate to large effect sizes (0.55-1.18). Additionally, the training resulted in a significant reduction in medial knee displacement during the overhead squat (p = 0.02).

INTERPRETATION

The finding indicate that our interventional protocol appears beneficial in increasing dorsiflexion range of motion among individuals with medial knee displacement. Additionally, improving dorsiflexion range of motion may be a promising direction for reducing medial knee displacement, which is a risk factor for anterior cruciate ligament injury.

A Comprehensive Summary of Systematic Reviews on Sports Injury Prevention Strategies

Background

A large volume of systematic reviews and meta-analyses has been published on the effectiveness of sports injury prevention programs.

Purpose

To provide a qualitative summary of published systematic reviews and meta-analyses that have examined the effectiveness of sports injury prevention programs on reducing musculoskeletal injuries.

Study Design

Systematic review; Level of evidence, 4.

Methods

We searched the PubMed, CINAHL, EMBASE, and the Cochrane databases for systematic reviews and meta-analyses that evaluated the effectiveness of sports injury prevention programs. We excluded published abstracts, narrative reviews, articles not published in English, commentaries, studies that described sports injury prevention strategies but did not assess their effectiveness, studies that did not assess musculoskeletal injuries, and studies that did not assess sports-related injuries. The most relevant results were extracted and summarized. Levels of evidence were determined per the Oxford Centre for Evidence-Based Medicine, and methodological quality was assessed using the AMSTAR-2 (A MeaSurement Tool to Assess systematic Reviews, revised version).

Results

A total of 507 articles were retrieved, and 129 were included. Articles pertaining to all injuries were divided into 9 topics: sports and exercise in general (n = 20), soccer (n = 13), ice hockey (n = 1), dance (n = 1), volleyball (n = 1), basketball (n = 1), tackle collision sports (n = 1), climbing (n = 1), and youth athletes (n = 4). Articles on injuries by anatomic site were divided into 11 topics: general knee (n = 8), anterior cruciate ligament (n = 34), ankle (n = 14), hamstring (n = 11), lower extremity (n = 10), foot (n = 6), groin (n = 2), shoulder (n = 1), wrist (n = 2), and elbow (n = 1). Of the 129 studies, 45.7% were ranked as evidence level 1, and 55.0% were evidence level 2. Based on the AMSTAR-2, 58.9% of the reviews reported a priori review methods, 96.1% performed a comprehensive literature search, 47.3% thoroughly described excluded articles, 79.1% assessed risk of bias for individual studies, 48.8% reported a valid method for statistical combination of data (ie, meta-analysis), 45.0% examined the effect of risk of bias on pooled study results, and 19.4% examined the risk for publication bias.

Conclusion

This comprehensive review provides sports medicine providers with a single source of the most up-to-date publications in the literature on sports injury prevention.

Injuries in elite-level women's football-a two-year prospective study in the Irish Women's National League

We investigated the pattern of injuries in elite-level women's football in Ireland, during a two-season prospective injury surveillance study in the Women's National League (WNL). Seven out of the eight clubs (271 players) in the WNL were followed prospectively during the 2018 and 2019 seasons. The injury incidence rate in matches (19.2/1000 h) was 7.5 times higher than in training (2.5/1000 h). Players, on average, sustained 0.69 injuries per season (266 injuries/383 player seasons), which equates to 15 time-loss injuries per season for a squad of 22 players. The majority of the injuries sustained by players were lower extremity injuries (85%), of which, 46% had a non-contact injury mechanism. Muscle, ligament, and contusion injuries were the most common injury types, while the ankle, knee, and thigh were the most commonly injured body sites. The most common injuries sustained over the two seasons were lateral ankle sprains (13.9%), hamstring strains (12.4%), knee meniscus/cartilage injuries (7.5%), adductor strains (6%), quadriceps strains (4.5%), and ankle contusions (4.5%). The injuries with the highest injury burden were ACL injuries (59 days lost/1000 h), knee meniscus/cartilage injuries (23/1000 h), lateral ankle sprains (21/1000 h), hamstring strains (12/1000 h), MCL sprains (11/1000 h), and quadriceps strains (11/1000 h). There were 8 ACL tears documented over the 2 seasons, which accounted for 28% of all time lost to injury with a mean days lost per injury of 247. We recommend that clubs in the WNL in Ireland should implement injury risk mitigation strategies, with a particular focus on injuries with a high injury burden.

Injury prevention of hamstring injuries through exercise interventions

INTRODUCTION

Hamstring injuries are the most prevalent time-loss injuries in sport, mainly in those modalities characterized by high-intensity and short-term actions, especially accelerations and decelerations during high-speed running. Expanding the knowledge about this type of injury and its preventive programs could be a key strategy to reduce the hamstring injury incidence. Thus, this review aimed to study the effectiveness of different preventive programs based on exercise interventions on reducing the hamstring injury incidence in athletes.

EVIDENCE ACQUISITION

An umbrella review was conducted through of PubMed/MEDLINE, Scopus, SPORTDiscus, Web of Science, Cochrane Library and Physiotherapy Evidence Database databases. The methodological quality of the included systematic reviews was assessed through the Assessing the Methodological Quality of Systematic Reviews 2 and the quality of the evidence was evaluated using the modified Grading of Recommendations Assessment, Development and Evaluation principles.

EVIDENCE SYNTHESIS

Eight systematic reviews and meta-analysis (40 primary studies) met the inclusion criteria, which included interventions based on eccentric strength, Nordic hamstring, proprioceptive training, stretching, FIFA11 and combined programs. From the qualitative synthesizes, three studies showed that eccentric-based training programs were effective; seventeen studies reported that Nordic hamstring-based programs were effective; three studies observed that stability training-based interventions were effective; two studies indicated that flexibility were effective; three studies claimed that FIFA11+based programs were effective; and two studies reported that combined programs were effective.

CONCLUSIONS

Exercise is a key strategy to reduce the hamstring injury incidence, being programs based on eccentric strength mainly by means of Nordic hamstring exercise, and on stability training, those programs which reported greater effectiveness.

Neuromuscular training for the prevention of ankle sprains in female athletes: a systematic review

Ankle sprains are a common sports-related injury, and female athletes are more likely to sustain this injury than their male counterparts. Previous reviews have evaluated the efficacy of prevention programs in reducing ankle sprains in athletes, but no reviews have specifically focused on female athletes. The objective of this systematic review was to examine the sex-specific effectiveness of neuromuscular training (NMT) programs in reducing the risk of ankle sprains in female athletes. A search of PubMed, Ovid Medline, Embase, and Web of Science databases was performed using the terms: (proprioception OR proprioceptive OR balance OR neuromuscular OR stability OR sensorimotor) AND training AND (ankle sprain OR ankle injury OR inversion injury OR ankle instability) AND (sport* OR athlet* or basketball OR volleyball OR soccer OR handball OR tennis OR netball OR hockey OR softball OR gymnastics OR danc* OR ballet OR cheerlead*) AND (female OR women OR girl). Studies selected for inclusion were written in English, evaluated female athletes in organized athletics or reported female-specific data for mixed-sex cohorts, included a non-NMT comparison, and used ankle injury rate outcome measures. Seven articles were selected for inclusion, which evaluated a combined 5,187 female basketball, handball, volleyball, soccer, and floorball players. Two studies reported significant differences between NMT participants and controls, concluding the greatest effects were observed in preventing non-contact ankle sprains. The remaining 5 studies, although not statistically significant, revealed an evident trend toward the efficacy of ankle injury prevention with NMT programs. Current available evidence supports the efficacy of NMT in preventing ankle sprains in female athletes. When designing NMT programs, investigators should consider utilizing comprehensive approaches that incorporate strength, balance, plyometric, and agility training as the studies with significant findings created comprehensive NMT programs. Further investigations into sport- and female-specific programs are warranted.

Postural control in top-level female volleyball players

Background

The aim of this study was to compare the postural control of the Poland national women’s volleyball team players with a control group of non-training young women. It was hypothesized that volleyball players use a specific balance control strategy due to the high motor requirements of their team sport.

Methods

Static postural sway variables were measured in 31 athletes and 31 non-training women. Participants were standing on a force plate with eyes open, and their center of pressure signals were recorded for the 20s with the sampling rate of 20 Hz in the medial-lateral (ML) and anterior-posterior (AP) planes.

Results

In both AP and ML planes, athletes had lower range and higher fractal dimension of the COP. They had also higher peak frequency than control group in the ML plane only. The remaining COP indices including variability, mean velocity and mean frequency did not display any intergroup differences.

Conclusion

It can be assumed that due to the high motor requirements of their sport discipline Polish female volleyball players have developed a unique posture control. On the court they have to distribute their sensory resources optimally between balance control and actions resulting from the specifics of the volleyball game. There are no clearly defined criteria for optimal postural strategies for elite athletes, but they rather vary depending on a given sport. The results of our research confirm this claim.

Trial registration

The tests were previously approved by the Bioethical Commission of the Chamber of Physicians in Opole. (Resolution No. 151/13.12.2007). This study adheres to the CONSORT guidelines.

THE EFFECT OF BLOOD GLUCOSE ON QUIET STANDING BALANCE IN YOUNG HEALTHY INDIVIDUALS

Falling is one of the leading causes of accidental injury and death among elderly adults and construction workers, with costs exceeding US$31 billion each year. Having good balance reduces the likelihood of falling - therefore it is important to determine which possible factors might influence balance. The purpose of this study was to determine if consuming three different types of breakfast altered blood glucose levels in such a way that young healthy individual's balance control was compromised. Balance was then measured while the subjects completed single- and dual-task standing trials with eyes open and closed. Although changing blood glucose did alter quiet standing balance - as measured by the separation distance between the COG and COP, the velocity of the COM, and the total distance traveled by the COG and COP along the anterior-posterior (AP) and medial-lateral (ML) axes - the results were contradictory to what was hypothesized. Subjects with lower blood glucose swayed less than those with higher blood glucose. This could potentially be due to the habitual skipping of breakfast in young adults. Though the changing of blood glucose did influence quiet standing balance of young healthy adults, it was not in a way which increased the risk of falling.

Bilateral Asymmetries Assessment in Elite and Sub-Elite Male Futsal Players

This study aimed to investigate morphological, functional, and neuromuscular asymmetries on futsal players’ lower limbs at different competitive levels. Sixteen male elite futsal players from the Spanish National Futsal League and thirteen male sub-elite futsal players from the third division participated in this study. Morphological asymmetry was assessed through bioelectrical impedance (fat-mass (g and %) and lean-mass (g)). Functional asymmetry was assessed by means of a 20-s static unipedal balance test. Finally, neuromuscular asymmetry was assessed using tensiomiography tests on both the rectus femoris (RF) and biceps femoris (BF) of each participant. The three tests conducted did not reveal significant bilateral asymmetries in elite players. On the other hand, sub-elite players showed significant bilateral asymmetry in fat-mass percentage between dominant and non-dominant limbs (+6%; CI95%: 1 to 11; ES: 0.88; p = 0.019). They also showed higher bilateral asymmetry in the delay time of the RF (+13%; CI95%: 7 to 21; ES: 1.3; p < 0.05). However, the static unipedal balance test (p > 0.05) did not evidence asymmetries regardless of the level of the participants. Elite futsal players do not develop bilateral asymmetries in lower limbs in the studied parameters. On the contrary, sub-elite players are likely to develop morphological and neuromuscular asymmetries between their dominant leg and non-dominant leg.

A Majority of Anterior Cruciate Ligament Injuries Can Be Prevented by Injury Prevention Programs: A Systematic Review of Randomized Controlled Trials and Cluster-Randomized Controlled Trials With Meta-analysis

BACKGROUND

Anterior cruciate ligament (ACL) injury prevention programs (IPPs) are generally accepted as being valuable for reducing injury risk. However, significant methodological limitations of previous meta-analyses raise questions about the efficacy of these programs and the extent to which meeting current best-practice ACL IPP recommendations influences the protective effect of these programs.

PURPOSE

To (1) estimate the protective effect of ACL IPPs while controlling for common methodological limitations of previous meta-analyses and (2) systematically categorize IPP components and factors related to IPP delivery to assess the validity of current best-practice IPP recommendations.

STUDY DESIGN

Systematic review with meta-analysis.

METHODS

A systematic search of 5 electronic scientific databases was conducted to identify studies testing the efficacy of ACL IPPs. Studies were included if (1) the intervention aimed to prevent ACL injury, (2) the incidence rate (IR) or other outcome data that made it possible to calculate the IR for both the intervention and control groups were reported, and (3) the study design was a prospective randomized controlled trial (RCT) or cluster-RCT.

RESULTS

Of the 2219 studies screened, 8 studies were included in the quantitative synthesis, and their analysis revealed a significant reduction in ACL IR when athletes received IPPs (IR ratio = 0.47; 95% CI, 0.30-0.73; P < .001). The majority of included IPPs tended to meet minimum best-practice recommendations and incorporated plyometric, strengthening, and agility exercises along with feedback on proper landing technique. However, the specific exercises included in each IPP and key factors related to IPP delivery were highly variable.

CONCLUSION

Despite limiting the analysis to only high-quality studies and controlling for time at risk and potential clustering effects, the study showed that ACL IPPs had a significant protective effect and reduced injury rates by 53%. However, significant variability in the specific exercises and the manner of program delivery suggests that ACL IPPs may be able to be designed within an overarching best-practice framework. This may allow practitioners the flexibility to develop IPPs that meet the specific characteristics of the target population and potentially increase the likelihood that these programs will be widely adopted and implemented.

Diagnosis, prevention and treatment of common lower extremity muscle injuries in sport - grading the evidence: a statement paper commissioned by the Danish Society of Sports Physical Therapy (DSSF)

This statement summarises and appraises the evidence on diagnosis, prevention and treatment of the most common lower extremity muscle injuries in sport. We systematically searched electronic databases, and included studies based on the highest available evidence. Subsequently, we evaluated the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation framework, grading the quality of evidence from high to very low. Most clinical tests showed very low to low diagnostic effectiveness. For hamstring injury prevention, programmes that included the Nordic hamstring exercise resulted in a hamstring injury risk reduction when compared with usual care (medium to large effect size; moderate to high quality of evidence). For prevention of groin injuries, both the FIFA 11+programme and the Copenhagen adductor strengthening programme resulted in a groin injury risk reduction compared with usual care (medium effect size; low to moderate quality of evidence). For the treatment of hamstring injuries, lengthening hamstring exercises showed the fastest return to play with a lower reinjury rate compared with conventional hamstring exercises (large effect size; very low to low quality of evidence). Platelet-rich plasma had no effect on time to return-to-play and reinjury risk (trivial effect size; moderate quality of evidence) after a hamstring injury compared with placebo or rehabilitation. At this point, most outcomes for diagnosis, prevention and treatment were graded as very low to moderate quality of evidence, indicating that further high-quality research is likely to have an important impact on the confidence in the effect estimates.

Making football safer for women: a systematic review and meta-analysis of injury prevention programmes in 11 773 female football (soccer) players

Objective

To evaluate the effects of injury prevention programmes on injury incidence in any women’s football code; explore relationships between training components and injury risk; and report injury incidence for women’s football.

Design

Systematic review and meta-analysis.

Data sources

Nine databases searched in August 2019.

Eligibility criteria

Randomised controlled trials evaluating any injury prevention programme (eg, exercise, education, braces) were included. Study inclusion criteria were: ≥20 female football players in each study arm (any age, football code or participation level) and injury incidence reporting.

Results

Twelve studies, all in soccer, met inclusion criteria, with nine involving adolescent teams (aged <18 years). All studies (except one) had a high risk of bias. Eleven studies examined exercise-based programmes, with most (9/11) including multiple (≥2) training components (eg, strength, plyometric, balance exercises). Multicomponent exercise programmes reduced overall (any reported) injuries (incidence rate ratio (IRR) 0.73, 95% CI 0.59 to 0.91) and ACL injuries (IRR 0.55, 95% CI 0.32 to 0.92). For exercise-based strategies (single-component and multicomponent), hamstring injuries were also reduced (IRR 0.40, 95% CI 0.17 to 0.95). While exercise-based strategies resulted in less knee, ankle and hip/groin injuries, and the use of multiple training components was associated with greater reductions in overall and knee injuries, further studies would be required to increase the precision of these results. The incidence of overall injuries in women’s football was 3.4 per 1000 exposure hours; with ankle injuries most common.

Conclusion

In women’s football, there is low-level evidence that multicomponent, exercise-based programmes reduce overall and ACL injuries by 27% and 45%, respectively.

PROSPERO registration number

CRD42018093527.

Electrocortical dynamics differentiate athletes exhibiting low- and high- ACL injury risk biomechanics

Anterior cruciate ligament (ACL) injuries are physically and emotionally debilitating for athletes,while motor and biomechanical deficits that contribute to ACL injury have been identified, limited knowledge about the relationship between the central nervous system (CNS) and biomechanical patterns of motion has impeded approaches to optimize ACL injury risk reduction strategies. In the current study it was hypothesized that high-risk athletes would exhibit altered temporal dynamics in their resting state electrocortical activity when compared to low-risk athletes. Thirty-eight female athletes performed a drop vertical jump (DVJ) to assess their biomechanical risk factors related to an ACL injury. The athletes' electrocortical activity was also recorded during resting state in the same visit as the DVJ assessment. Athletes were divided into low- and high-risk groups based on their performance of the DVJ. Recurrence quantification analysis was used to quantify the temporal dynamics of two frequency bands previously shown to relate to sensorimotor and attentional control. Results revealed that high-risk participants showed more deterministic electrocortical behavior than the low-risk group in the frontal theta and central/parietal alpha-2 frequency bands. The more deterministic resting state electrocortical dynamics for the high-risk group may reflect maladaptive neural behavior-excessively stable deterministic patterning that makes transitioning among functional task-specific networks more difficult-related to attentional control and sensorimotor processing neural regions.

Effects of Soccer Training on Body Balance in Young Female Athletes Assessed Using Computerized Dynamic Posturography

The aim of this study was to determine the effect of regular soccer training on the balance system for young women. Computerized dynamic posturography of female footballers (n = 25) and control group (n = 50) was assessed during three tests: Sensory Organization Test, Motor Control Test, and Adaptation Test. Statistically significant differences between the groups was found in Composite Equilibrium Score with higher values, indicating better postural stability, for footballers. Regular trainees also showed better usefulness of vestibular system while maintaining balance. Weight symmetry of the lower limbs during Motor Control Test also showed statistically significant differences between the groups. This study shows that female footballers have better postural stability than their inactive peers and that regular workouts may improve the balance system.

Injury Risk Factors Integrated Into Self-Guided Real-Time Biofeedback Improves High-Risk Biomechanics

CONTEXT

Existing anterior cruciate ligament (ACL) injury prevention programs have failed to reverse the high rate of ACL injuries in adolescent female athletes.

OBJECTIVE

This investigation attempts to overcome factors that limit efficacy with existing injury prevention programs through the use of a novel, objective, and real-time interactive visual feedback system designed to reduce the biomechanical risk factors associated with ACL injuries.

DESIGN

Cross-over study.

SETTING

Medical center laboratory.

PARTICIPANTS

A total of 20 females (age = 19.7 [1.34] y; height = 1.74 [0.09] m; weight = 72.16 [12.45] kg) participated in this study.

METHODS

Participants performed sets of 10 bodyweight squats in each of 8 training blocks (ie, 4 real-time and 4 control blocks) and 3 testing blocks for a total of 110 squats. Feedback conditions were blocked and counterbalanced with half of participants randomly assigned to receive the real-time feedback block first and half receiving the control (sham) feedback first.

RESULTS

Heat map analysis revealed that during interaction with the real-time feedback, squat performance measured in terms of key biomechanical parameters was improved compared with performance when participants squatted with the sham stimulus.

CONCLUSIONS

This study demonstrates that the interactive feedback system guided participants to significantly improve movement biomechanics during performance of a body weight squat, which is a fundamental exercise for a longer term ACL injury risk reduction intervention. A longer training and testing period is necessary to investigate the efficacy of this feedback approach to effect long-term adaptations in the biomechanical risk profile of athletes.

Clinical and Biomechanical Efficacies of Mechanical Perturbation Training After Anterior Cruciate Ligament Rupture

CONTEXT

Manual perturbation training improves knee functional performance and mitigates abnormal gait in patients with anterior cruciate ligament (ACL) rupture. However, manual perturbation training is time- and labor-intensive for therapists.

OBJECTIVE

To investigate whether perturbation training administered using a mechanical device can provide effects similar to manual training on clinical measures and knee biomechanics after ACL rupture.

DESIGN

Prospective cohort (therapeutic) study. A 2 × 2 analysis of variance was used for statistical analysis.

SETTING

A clinical and biomechanical laboratory.

PATIENTS

Eighteen level I/II patients with acute ACL ruptures participated in this preliminary study.

INTERVENTION

Nine patients received mechanical perturbation training on an automated mechanical device (mechanical group), and 9 patients received manual perturbation training (manual group).

OUTCOME MEASURES

Patients completed performance-based testing (quadriceps strength and single-legged hop tests), patient-reported questionnaires (Knee Outcome Survey-Activities of Daily Living Scale, Global Rating Score, and International Knee Documentation Committee 2000), and 3-dimensional gait analysis before (pretesting) and after (posttesting) training.

RESULTS

There was no significant group-by-time interaction found for all measures (P ≥ .18). Main effects of time were found for International Knee Documentation Committee 2000 (pretesting: 69.10 [10.95], posttesting: 75.14 [7.19]), knee excursion during weight-acceptance (pretesting: 16.01° [3.99°]; posttesting: 17.28° [3.99°]) and midstance (pretesting: 14.78° [4.13°]; posttesting: 16.92° [4.53°]) and external knee-flexion moment (pretesting: 0.43 [0.11] N m/kg/m; posttesting: 0.48 [0.11] N m/kg/m) (P ≤ .04). After accounting for pretesting groups' differences, the mechanical group scored significantly higher on triple hops (mechanical: 96.73% [6.65%]; manual: 84.97% [6.83%]) and 6-m timed hops (mechanical: 102.07% [9.50%]; manual: 91.21 [9.42%]) (P ≤ .047) compared with manual group.

CONCLUSION

The clinical significance of this study is the mechanical perturbation training produced effects similar to manual training, with both training methods were equally  effective at improving patients' perception of knee function and increasing knee excursion and external flexion moment during walking after acute ACL rupture. Mechanical perturbation training is a potential treatment to improve patients' functional and biomechanical outcomes after ACL rupture.

"What's my risk of sustaining an ACL injury while playing sports?" A systematic review with meta-analysis

OBJECTIVE

To estimate the incidence proportion (IP) and incidence rate (IR) for ACL injury in athletes.

DESIGN

Systematic review with meta-analysis DATA SOURCES: The PubMed, CINAHL and SPORTDiscus electronic databases were searched from inception to 20 January 2017.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies were included if they reported total number of participants/population by sex, total number of ACL injuries by sex and total person-time by sex.

RESULTS

Fifty-eight studies were included. The IP and IR of ACL injury in female athletes were 3.5% (1 out of every 29 athletes) and 1.5/10 000 athlete-exposures over a period of 1 season-25 years. The IP and IR of ACL injury in male athletes were 2.0% (1 out of every 50 athletes) and 0.9/10 000 athlete-exposures over a period of 1-25 years. Female athletes had a higher relative risk (RR) for ACL injury compared with males (RR=1.5; 95% CI 1.2 to 1.9; P<0.01) and a higher incidence rate ratio (IRR) of ACL injury compared with males over 1 season-25 years (IRR=1.7; 95% CI 1.4 to 2.2; P<0.010). When accounting for participation level, the disparity in the IR between female and male athletes was highest for amateur athletes compared with intermediate and elite athletes (IRR=2.1; 95% CI 1.3 to 3.4; P<0.01; I²=82%). Amateur female athletes remained at higher risk of ACL injury than did with amateur male athletes. In studies where follow-up length was <1 year, female athletes had a higher IR of ACL injury than did to males (IRR=1.7; 95% CI 1.3 to 2.2; P<0.01). Where follow-up was 1 year and beyond, there was no sex difference in the IR of ACL injury (IRR=2.1; 95% CI 0.9 to 4.8; P=0.06; I²=65%).

SUMMARY/CONCLUSIONS

One in 29 female athletes and 1 in 50 male athletes ruptured their ACL in a window that spanned from 1season to 25 years. The IR of ACL injury among female athletes in a season was 1.7 times higher than the IR of ACL injury among male athletes and the IP of ACL injury among female athletes was 1.5 times higher than the IP of ACL injury among male athletes. The reported sex disparity in ACL injury rates is independent of participation level and length of follow-up.

Evidence-Based Best-Practice Guidelines for Preventing Anterior Cruciate Ligament Injuries in Young Female Athletes: A Systematic Review and Meta-analysis

BACKGROUND

Injury prevention neuromuscular training (NMT) programs reduce the risk for anterior cruciate ligament (ACL) injury. However, variation in program characteristics limits the potential to delineate the most effective practices to optimize injury risk reduction.

PURPOSE

To evaluate the common and effective components included in ACL NMT programs and develop an efficient, user-friendly tool to assess the quality of ACL NMT programs.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

Study inclusion required (1) a prospective controlled trial study design, (2) an NMT intervention aimed to reduce incidence of ACL injury, (3) a comparison group, (4) ACL injury incidence, and (5) female participants. The following data were extracted: year of publication, study design, sample size and characteristics, and NMT characteristics including exercise type and number per session, volume, duration, training time, and implementer training. Analysis entailed both univariate subgroup and meta-regression techniques using random-effects models.

RESULTS

Eighteen studies were included in the meta-analyses, with a total of 27,231 participants, 347 sustaining an ACL injury. NMT reduced the risk for ACL injury from 1 in 54 to 1 in 111 (odds ratio [OR], 0.51; 95% CI, 0.37-0.69]). The overall mean training volume was 18.17 hours for the entire NMT (24.1 minutes per session, 2.51 times per week). Interventions targeting middle school or high school-aged athletes reduced injury risk (OR, 0.38; 95% CI, 0.24-0.60) to a greater degree than did interventions for college- or professional-aged athletes (OR, 0.65; 95% CI, 0.48-0.89). All interventions included some form of implementer training. Increased landing stabilization and lower body strength exercises during each session improved prophylactic benefits. A meta-regression model and simple checklist based on the aforementioned effective components (slope = -0.15, P = .0008; intercept = 0.04, P = .51) were developed to allow practitioners to evaluate the potential efficacy of their ACL NMT and optimize injury prevention effects.

CONCLUSION

Considering the aggregated evidence, we recommend that ACL NMT programs target younger athletes and use trained implementers who incorporate lower body strength exercises (ie, Nordic hamstrings, lunges, and heel-calf raises) with a specific focus on landing stabilization (jump/hop and hold) throughout their sport seasons.

CLINICAL RELEVANCE

Clinicians, coaches, athletes, parents, and practitioners can use the developed checklist to gain insight into the quality of their current ACL NMT practices and can use the tool to optimize programming for future ACL NMT to reduce ACL injury risk.

Anterior cruciate ligament reconstruction and dynamic stability at time of release for return to sport

OBJECTIVE

Examine dynamic stability using Dynamic Postural Stability Index (DPSI) in athletes following anterior cruciate ligament reconstruction (ACLR) at time of release for return-to-sport (RTS), compared to matched controls.

DESIGN

Cross-sectional case-control study.

SETTING

Sports medicine clinic.

SUBJECTS

Fifteen ACLR athletes who had completed post-operative rehabilitation and were within 6 weeks following release to RTS were age-, gender-, and activity-matched to 15 healthy controls.

MAIN OUTCOME MEASURES

Ground reaction forces (GRFs) were collected using a portable force plate during stabilization from three different single-leg landing tasks. A composite DPSI was calculated using GRFs.

RESULTS

Compared to matched controls, ACLR athletes within 6 weeks of release for RTS did not significantly differ in dynamic postural stability and there were no significant differences between the involved and uninvolved limbs in the ACLR group.

CONCLUSION

Current findings indicate that dynamic postural stability, as measured using the DPSI, is not significantly different in ACLR subjects at time of release for RTS compared to matched controls. In addition, the DPSI was not significantly different between the involved and uninvolved limbs in the ACLR subjects. The results suggest that the post-ACLR rehabilitation program utilized may have adequately restored postural stability in this particular sample.

Anterior Cruciate Ligament Injury Risk in Sport: A Systematic Review and Meta-Analysis of Injury Incidence by Sex and Sport Classification

OBJECTIVE

To evaluate sex differences in incidence rates (IRs) of anterior cruciate ligament (ACL) injury by sport type (collision, contact, limited contact, and noncontact).

DATA SOURCES

A systematic review was performed using the electronic databases PubMed (1969-January 20, 2017) and EBSCOhost (CINAHL, SPORTDiscus; 1969-January 20, 2017) and the search terms anterior cruciate ligament AND injury AND (incidence OR prevalence OR epidemiology).

STUDY SELECTION

Studies were included if they provided the number of ACL injuries and the number of athlete-exposures (AEs) by sex or enough information to allow the number of ACL injuries by sex to be calculated. Studies were excluded if they were analyses of previously reported data or were not written in English.

DATA EXTRACTION

Data on sport classification, number of ACL injuries by sex, person-time in AEs for each sex, year of publication, sport, sport type, and level of play were extracted for analysis.

DATA SYNTHESIS

We conducted IR and IR ratio (IRR) meta-analyses, weighted for study size and calculated. Female and male athletes had similar ACL injury IRs for the following sport types: collision (2.10/10 000 versus 1.12/10 000 AEs, IRR = 1.14, P = .63), limited contact (0.71/10 000 versus 0.29/10 000 AEs, IRR = 1.21, P = .77), and noncontact (0.36/10 000 versus 0.21/10 000 AEs, IRR = 1.49, P = .22) sports. For contact sports, female athletes had a greater risk of injury than male athletes did (1.88/10 000 versus 0.87/10 000 AEs, IRR = 3.00, P < .001). Gymnastics and obstacle-course races were outliers with respect to IR, so we created a sport category of fixed-object, high-impact rotational landing (HIRL). For this sport type, female athletes had a greater risk of ACL injury than male athletes did (4.80/10 000 versus 1.75/10 000 AEs, IRR = 5.51, P < .001), and the overall IRs of ACL injury were greater than all IRs in all other sport categories.

CONCLUSIONS

Fixed-object HIRL sports had the highest IRs of ACL injury for both sexes. Female athletes were at greater risk of ACL injury than male athletes in contact and fixed-object HIRL sports.

Specific interventions for prevention of muscle injury in lower limbs: systematic review and meta-analysis

Abstract Introduction: Muscle injuries show an incidence associated with extreme stretching, or even a high-intensity eccentric contraction. Such injuries cause severe damage to athletes, including lower performance, withdrawal, and psychological distress. In this scenario, the study of effective preventive methods is an indispensable factor in the routine of professional athletes, to reduce the incidence of injuries. Objective: To verify the effectiveness of three different interventions (warm-up, neuromuscular training, and eccentric exercise) to prevent muscle injuries in the lower limbs. Method: We searched the Cochrane Library, EMBASE, SPORTDiscus, PEDro, and PubMed databases from the earliest records until January 20, 2018. The search was performed from word combinations such as clinical trial, muscle strain, injury prevention. The data related to the outcome of prevention were grouped in meta-analysis and described in Risk Ratio (RR) with 95% confidence interval. Results: Sixteen studies were included: five assessed eccentric exercise, three investigated neuromuscular training, and eight observed warm-up. The eccentric exercise (RR = 3.49, 95% CI 2.36, 5.16, p < 0.00001) and the neuromuscular training (RR = 2.73, 95% CI 2.03, 2.68, p < 0.00001) showed significant effects on the prevention of muscle injuries in lower limbs. On the other hand, warm-up (RR = 1.57, 95% CI 0.92, 2.7, p = 0.10) was irrelevant in reducing the incidence of injuries in the body segment investigated. Conclusion: The outcomes presented provide clinical relevance inherent in the field practices, with intrinsic potential for practical application in the management of specific preventive techniques.

Applying the Socio-Ecological Model to barriers to implementation of ACL injury prevention programs: A systematic review

BACKGROUND

Preventing anterior cruciate ligament (ACL) injuries is important to avoid long-term adverse health consequences. Identifying barriers to implementation of these prevention programs is crucial to reducing the incidence of these injuries. Our purpose was to identify barriers of implementation for ACL injury prevention programs and suggest mechanisms for reducing the barriers through application of a Socio-Ecological Model (SEM).

METHODS

Studies investigating ACL prevention program effectiveness were searched in Medline via PubMed and the Cochrane Library, and a subsequent review of the references of the identified articles, yielded 15 articles total. Inclusion criteria encompassed prospective controlled trials, published in English, with ACL injuries as the primary outcome. Studies were independently appraised by 2 reviewers for methodological quality using the PEDro scale. Barriers to implementation were identified when reported in at least 2 separate studies. A SEM was used to suggest ways to reduce the identified barriers.

RESULTS

Five barriers were identified: motivation, time requirements, skill requirements for program facilitators, compliance, and cost. The SEM suggested ways to minimize the barriers at all levels of the model from the individual through policy levels.

CONCLUSION

Identification of barriers to program implementation and suggesting how to reduce them through the SEM is a critical first step toward enabling ACL prevention programs to be more effective and ultimately reducing the incidence of these injuries.

Intervention Strategies Used in Sport Injury Prevention Studies: A Systematic Review Identifying Studies Applying the Haddon Matrix

BACKGROUND

Prevention of sport injuries is crucial to maximise the health and societal benefits of a physically active lifestyle. To strengthen the translation and implementation of the available evidence base on effective preventive measures, a range of potentially relevant strategies should be considered.

OBJECTIVE

Our aim was to identify and categorise intervention strategies for the prevention of acute sport injuries evaluated in the scientific literature, applying the Haddon matrix, and identify potential knowledge gaps.

METHODS

Five electronic databases were searched (PubMed, EMBASE, SPORTDiscus, CINAHL, Cochrane) for studies that evaluated the effect of interventions on the occurrence of acute sport injuries. Studies were required to include a control group/condition, prospective data collection, and a quantitative injury outcome measure.

RESULTS

A total of 155 studies were included, mostly randomised controlled trials (43%). The majority of studies (55%) focussed on strategies requiring a behavioural change on the part of athletes. Studies predominantly evaluated the preventive effect of various training programmes targeted at the 'pre-event' phase (n = 73) and the use of equipment to avoid injury in the 'event phase' (n = 29). A limited number of studies evaluated the preventive effect of strategies geared at rules and regulations (n = 14), and contextual modifications (n = 18). Studies specifically aimed at preventing re-injuries were a minority (n = 8), and were mostly related to ankle sprains (n = 5).

CONCLUSIONS

Valuable insight into the extent of the evidence base of sport injury prevention studies was obtained for 20 potential intervention strategies. This approach can be used to monitor potential gaps in the knowledge base on sport injury prevention.

Meta-analysis of meta-analyses of anterior cruciate ligament injury reduction training programs

Several meta-analyses have been published on the effectiveness of anterior cruciate ligament (ACL) injury prevention training programs to reduce ACL injury risk, with various degrees of risk reduction reported. The purpose of this research was to perform a systematic review and meta-analysis of overlapping meta-analyses evaluating the effectiveness of ACL injury prevention training programs so as to summarize the amount of reduction in risk for all ACL and non-contact ACL injuries into a single source, and determine if there were sex differences in the relative efficacy of ACL injury prevention training programs. Five databases (Medline, PubMed, Embase, CINAHL, and Cochrane) were searched to identify meta-analyses that evaluated the effectiveness of ACL injury prevention training programs on ACL injury risk. ACL injury data were extracted and the results from each meta-analysis were combined using a summary meta-analysis based on odds ratios (OR). Eight meta-analyses met eligibility criteria. Six of the eight only included data for female athletes. Summary meta-analysis showed an overall 50% reduction (OR = 0.5 [0.41-0.59]; I²  = 15%) in the risk of all ACL injuries in all athletes and a 67% reduction (OR = 0.33 [0.27-0.41]; I²  = 15%) for non-contact ACL injuries in females. This paper combines all previous meta-analyses into a single source and shows conclusive evidence that ACL injury prevention programs reduce the risk of all ACL injuries by half in all athletes and non-contact ACL injuries by two-thirds in female athletes. There is insufficient data to make conclusions as to the effectiveness of ACL injury prevention programs in male athletes. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2696-2708, 2018.

Exercise-Based Knee and Anterior Cruciate Ligament Injury Prevention

The Academy of Orthopaedic Physical Therapy and the American Academy of Sports Physical Therapy have an ongoing effort to create evidence-based clinical practice guidelines (CPGs) for orthopaedic and sports physical therapy management and prevention of musculoskeletal impairments described in the World Health Organization's International Classification of Functioning, Disability and Health (ICF). This particular guideline focuses on the exercise-based prevention of knee injuries. J Orthop Sports Phys Ther. 2018;48(9):A1-A42. doi:10.2519/jospt.2018.0303.

Effects of proprioceptive training on the incidence of ankle sprain in athletes: systematic review and meta-analysis

OBJECTIVE:

To investigate how dynamic neuromuscular control, postural sway, joint position sense, and incidence of ankle sprain are influenced by balance training in athletes compared with the control group in randomized clinical trials.

DATA SOURCES:

The search strategy included MEDLINE, Physical Therapy Evidence Database, Cochrane Central Register of Controlled Trials, and Latin American and Caribbean Center on Health Sciences Information. Randomized controlled trials (RCTs) were published by June of 2018.

METHODS:

RCTs that evaluate the effectiveness of proprioception in these outcomes: dynamic neuromuscular control, postural sway, joint position, and the incidence of ankle sprains in athletes aged between 18 and 35 years. Two reviewers independently screened the searched records, extracted the data, and assessed risk of bias. The treatment effect sizes were pooled in a meta-analysis using the RevMan 5.2 software. Internal validity was assessed through topics suggested by Cochrane Collaborations.

RESULTS:

Of the 12 articles included ( n = 1817), eight were in the meta-analysis ( n = 1722). The balance training reduced the incidence of ankle sprains in 38% compared with the control group ( RR: 0.62; 95% CI: 0.43-0.90). In relation to the dynamic neuromuscular control, the training showed increase in the distance of reach in the anterior (0.62 cm, 95% CI: 0.13-1.11), posterolateral (4.22 cm, 95% CI: 1.76-6.68), and posteromedial (3.65 cm, 95% CI: 1.03-6.26) through the Star Excursion Balance test. Furthermore, training seems to improve postural sway and joint position sense.

CONCLUSION:

Balance training reduces the incidence of ankle sprains and increases dynamic neuromuscular control, postural sway, and the joint position sense in athletes.

The Influence of Attentional Focus on Balance Control over Seven Days of Training

This study examined the training effect of attentional focus (external focus, internal focus, or no focus instructions) on a dynamic balance task. Participants completed baseline balance testing, seven consecutive days of dynamic balance board training, and retention testing 24 hours after the last session. The novel finding of this study was the presence of a training effect on balance control when adopting an external focus relative to an internal focus or no focus instructions. Further, we report the unique observation that more patterned behavior was adopted regardless of the focus instructions. These findings provide insight into how instructions can be altered to enhance human balance control and complement the constrained-action hypothesis.

'What's my risk of sustaining an ACL injury while playing football (soccer)?' A systematic review with meta-analysis

OBJECTIVE

To estimate the incidence proportion (IP) and incidence rate (IR) of ACL injury in football players.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

PubMed, CINAHL and SPORTDiscus electronic databases were searched from inception to 20 January 2017.

ELIGIBILITY CRITERIA FOR SELECTING STUDY

Studies that reported the total number of participants/population by sex, total number of ACL injuries by sex and total person-time by sex were included.

RESULTS

Twenty-eight studies were included. The IP and IR of ACL injury in female football players were 2.0% (95% CI 1.2% to 3.1%) and 2.0/10 000 athlete exposures (AEs) (95% CI 1.6 to 2.6; I²=91%) over a period of one season to 4 years. The IP and IR of ACL injury in male players were 3.5% (95% CI 0.7% to 8.2%) and 0.9/10 000 AEs (95% CI 0.7 to 1.1; I²=94%). Studies that evaluated matched cohorts of female and male players showed no difference in IP (relative risk=1.2; 95% CI 0.9 to 1.6; P=0.47) over a period of one season to 4 years. Women were at greater risk than men (incidence rate ratio (IRR)=2.2; 95% CI 1.6 to 3.1; I²=83%; P<0.001). When accounting for participation level, the difference in IR between women and men was greatest for intermediate players (IRR=2.9; 95% CI 2.4 to 3.6) compared with amateur (IRR=2.6; 95% CI 1.4 to 4.8) and elite (IRR=2.0; 95% CI 1.1 to 3.4) players.

SUMMARY/CONCLUSION

Overall, more men sustained ACL injury in football. There was no difference in the relative risk of ACL injury between female and male football players in a window that spanned one season to 4 years. The IR of ACL injury among women was 2.2 times higher than the IR of ACL injury among men. The reported sex disparity in ACL injury was independent of participation level.

Video Analysis of Anterior Cruciate Ligament Tears in Professional American Football Athletes

BACKGROUND

Anterior cruciate ligament (ACL) injuries are prevalent in contact sports that feature cutting and pivoting, such as American football. These injuries typically require surgical treatment, can result in significant missed time from competition, and may have deleterious long-term effects on an athlete's playing career and health. While the majority of ACL tears in other sports have been shown to occur from a noncontact mechanism, it stands to reason that a significant number of ACL tears in American football would occur after contact, given the nature of the sport. Hypothesis/Purpose: The purpose was to describe the mechanism, playing situation, and lower extremity limb position associated with ACL injuries in professional American football players through video analysis to test the hypothesis that a majority of injuries occur via a contact mechanism.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A retrospective cohort of National Football League (NFL) players with ACL injuries from 3 consecutive seasons (2013-2016) was populated by searching publicly available online databases and other traditional media sources. Of 156 ACL injuries identified, 77 occurred during the regular season and playoffs, with video analysis available for 69 injuries. The video of each injury was independently viewed by 2 reviewers to determine the nature of the injury (ie, whether it occurred via a noncontact mechanism), the position of the lower extremity, and the football activity at the time of injury. Playing surface, player position, and time that the injury occurred were also recorded.

RESULTS

Contrary to our hypothesis, the majority of ACL injuries occurred via a noncontact mechanism (50 of 69, 72.5%), with the exception of injury to offensive linemen, who had a noncontact mechanism in only 20% of injuries. For noncontact injuries, the most common football activity at the time of injury was pivoting/cutting, and the most common position of the injured extremity included hip abduction/flexion, early knee flexion/abduction, and foot abduction/external rotation. There was no association between injury mechanism and time of injury or playing surface in this cohort.

CONCLUSION

In this study of players in the NFL, the majority of ACL tears involved a noncontact mechanism, with the lower extremity exhibiting a dynamic valgus moment at the knee. These findings suggest that ACL injury prevention programs may reduce the risk of noncontact ACL tears in American football players.

Anterior cruciate ligament ruptures in German elite soccer players: Epidemiology, mechanisms, and return to play

BACKGROUND

Anterior cruciate ligament ruptures (ACLRs) are severe sports-related injuries with significant consequences for affected players and teams. This study aims to identify the epidemiology and injury-related lay-off after ACLR in professional male soccer players from the first-division German Bundesliga.

METHODS

Exposure times and incidence of anterior cruciate ligament ruptures were collected during 7.5 consecutive seasons using two media-based registers.

RESULTS

A total of 72 total ACLRs were registered in 66 different players with an incidence of 0.040 per 1000h of exposure (95% CI 0.009-0.12). On average there were 9.6 ACLRs per season and 0.53 per team and season. The mean age of players affected was 24 (standard deviation±3.6) years. The number of ACLRs recorded per season fluctuated during the period observed. Goalkeepers are significantly (P<0.05) less prone to suffer an ACLR compared to outfield players.

CONCLUSIONS

Understanding ACLR loading mechanisms, knowing risk factors for the injury and mean off time after ACLR are essential information for the coach, the medical staff, the elite soccer players, the insurance and team managers. Our results are in accordance with reports based on information from medical team staff. Therefore, our analysis of ACLR based on media sources may serve as an alternative for injury reports in elite soccer. The information of this study may be helpful for the medical staff taking care of professional soccer players and for orthopedic surgeons performing ACL reconstructions in this patient population.

Effect of Hip-Focused Injury Prevention Training for Anterior Cruciate Ligament Injury Reduction in Female Basketball Players: A 12-Year Prospective Intervention Study

BACKGROUND

Programs to prevent anterior cruciate ligament (ACL) injuries in female basketball players are scarce. Also, ACL injury prevention training that focuses on hip joint function has not been reported.

PURPOSE

To determine the effectiveness of a hip-focused ACL injury prevention program in female basketball players.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A prospective intervention study was conducted for 12 years. Incidence rates of ACL injuries were collected in the first 4 years (observation period) from college female basketball players. After the observation period, a hip-focused ACL injury prevention program was implemented for 8 years (intervention period). A total of 309 players (mean ± SD age, 19.6 ± 1.2 years; height, 163.7 ± 5.6 cm; weight, 59.1 ± 5.1 kg; body mass index, 22.0 ± 1.4) were tracked in the observation period and compared with 448 players (age, 19.6 ± 1.1 years; height, 162.6 ± 5.8 cm; weight, 58.0 ± 5.7 kg; body mass index, 21.9 ± 1.5) who participated in the intervention period. Athlete-exposures (AEs), ACL numbers and mechanisms of injury (MOIs), relative risk (RR), absolute risk reduction (ARR), numbers needed to treat (NNT), and compliance were analyzed.

RESULTS

There were 16 ACL injuries (13 noncontact MOIs) in the 4-year observation period, whereas 9 ACL injuries (8 noncontact MOIs) were recorded in the 8-year intervention period. The overall ACL injury incidence was 0.25/1000 AEs in the 4-year observation period compared with 0.10/1000 AEs in the 8-year intervention period, respectively. Compared with the 4-year observation period, significant RR reduction was observed (0.38; 95% CI, 0.17-0.87; P = .017) with ARR and NNT of 0.032 (95% CI, 0.027-0.037) and 31.6 (95% CI, 27.1-37.7), respectively, in the 8-year intervention period. The noncontact ACL injury incidence was 0.21 per 1000 AEs during the 4-year observation period compared with 0.08/1000 AEs in the 8-year intervention period, which also showed significant RR reduction (0.37; 95% CI, 0.15-0.92; P = .026), with ARR and NNT of 0.024 (95% CI, 0.020-0.029) and 41.3 (95% CI, 34.6-51.3), respectively. The mean compliance rate during the intervention periods (8 years) was 89%.

CONCLUSION

A hip-focused injury prevention program demonstrated significant reduction in the incidence of ACL injury in female collegiate basketball players.

Prevention of Anterior Cruciate Ligament Rupture in Female Athletes: A Systematic Review

BACKGROUND

A number of reports have been published on the effectiveness and design of intervention programs for the prevention of rupture of the anterior cruciate ligament (ACL) in female athletes. The purpose of this study was to systematically review the literature to determine the effectiveness of neuromuscular training programs in preventing ACL injury in female athletes.

METHODS

A systematic review was performed with use of the PubMed, MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases. The search terms included "anterior cruciate ligament" and "ACL" combined with "prevention" and "intervention." The searches included material indexed by September 30, 2013. Data concerning study design, the characteristics of participants, the details of the neuromuscular programs, the types of sports, and number of ACL ruptures were extracted from the studies. Study heterogeneity was assessed with funnel plot and Egger regression methods. Pooled effects were calculated with use of a DerSimonian-Laird random-effects model. The number needed to treat was calculated on the basis of pooled incidence data.

RESULTS

The risk of ACL rupture was 1.83 times higher for female athletes who did not participate in neuromuscular ACL-prevention training programs (odds ratio [OR], 1.83; 95% confidence interval [95% CI], 1.08 to 3.10; p = 0.02). In studies that focused exclusively on soccer, the risk of ACL rupture was 2.62 times higher for nonparticipating athletes (OR, 2.62; 95% CI, 1.59 to 4.32; p < 0.01). When the data were analyzed according to the timing of the intervention, no significant effects were found. In studies in which the program took place both preseason and in-season, the risk (odds ratio) of ACL rupture for nonparticipating athletes was 2.34 (95% CI, 0.82 to 6.7; p = 0.11). In studies in which the intervention took place in-season only, the risk (odds ratio) of ACL rupture for nonparticipating athletes was 1.25 (95% CI, 0.23 to 6.75; p = 0.8). The number needed to treat to prevent a single ACL rupture was 128.7 athletes. We found no significant heterogeneity among the included studies. The I value was 35.40% (p = 0.11). No significant publication bias was found in our included studies.

CONCLUSIONS

The results of this systematic review and meta-analysis favor a protective effect of neuromuscular training programs on the risk of ACL rupture in female athletes. This protective effect is more pronounced in soccer players. Additional research is needed to design the optimal training program.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions to Authors for a complete description of levels of evidence.

National Athletic Trainers' Association Position Statement: Prevention of Anterior Cruciate Ligament Injury

OBJECTIVE

  To provide certified athletic trainers, physicians, and other health care and fitness professionals with recommendations based on current evidence regarding the prevention of noncontact and indirect-contact anterior cruciate ligament (ACL) injuries in athletes and physically active individuals.

BACKGROUND

  Preventing ACL injuries during sport and physical activity may dramatically decrease medical costs and long-term disability. Implementing ACL injury-prevention training programs may improve an individual's neuromuscular control and lower extremity biomechanics and thereby reduce the risk of injury. Recent evidence indicates that ACL injuries may be prevented through the use of multicomponent neuromuscular-training programs.

RECOMMENDATIONS

  Multicomponent injury-prevention training programs are recommended for reducing noncontact and indirect-contact ACL injuries and strongly recommended for reducing noncontact and indirect-contact knee injuries during physical activity. These programs are advocated for improving balance, lower extremity biomechanics, muscle activation, functional performance, strength, and power, as well as decreasing landing impact forces. A multicomponent injury-prevention training program should, at minimum, provide feedback on movement technique in at least 3 of the following exercise categories: strength, plyometrics, agility, balance, and flexibility. Further guidance on training dosage, intensity, and implementation recommendations is offered in this statement.

Proprioceptive Training for the Prevention of Ankle Sprains: An Evidence-Based Review

Reference:  Schiftan GS, Ross LA, Hahne AJ. The effectiveness of proprioceptive training in preventing ankle sprains in sporting populations: a systematic review and meta-analysis. J Sci Med Sport. 2015;18(3):238-244.

CLINICAL QUESTION

  Does the use of proprioceptive training as a sole intervention decrease the incidence of initial or recurrent ankle sprains in the athletic population?

DATA SOURCES

  The authors completed a comprehensive literature search of MEDLINE, CINAHL, SPORTDiscus, and Physiotherapy Evidence Database (PEDro) from inception to October 2013. The reference lists of all identified articles were manually screened to obtain additional studies. The following key words were used. Phase 1 population terms were sport*, athlet*, and a combination of the two. Phase 2 intervention terms were propriocept*, balance, neuromusc* adj5 train*, and combinations thereof. Phase 3 condition terms were ankle adj5 sprain*, sprain* adj5 ankle, and combinations thereof.

STUDY SELECTION

  Studies were included according to the following criteria: (1) the design was a moderate- to high-level randomized controlled trial (>4/10 on the PEDro scale), (2) the participants were physically active (regardless of previous ankle injury), (3) the intervention group received proprioceptive training only, compared with a control group that received no proprioceptive training, and (4) the rate of ankle sprains was reported as a main outcome. Search results were limited to the English language. No restrictions were placed on publication dates.

DATA EXTRACTION

  Two authors independently reviewed the studies for eligibility. The quality of the pertinent articles was assessed using the PEDro scale, and data were extracted to calculate the relative risk. Data extracted were number of participants, intervention, frequency, duration, follow-up period, and injury rate.

MAIN RESULTS

  Of the initial 345 studies screened, 7 were included in this review for a total of 3726 participants. Three analyses were conducted for proprioceptive training used (1) to prevent ankle sprains regardless of history (n = 3654), (2) to prevent recurrent ankle sprains (n = 1542), or (3) as the primary preventive measure for those without a history of ankle sprain (n = 946). Regardless of a history of ankle sprain, participants had a reduction in ankle-sprain rates (relative risk [RR] = 0.65, 95% confidence interval [CI] = 0.55, 0.77; numbers needed to treat [NNT] = 17, 95% CI = 11, 33). For individuals with a history of ankle sprains, proprioceptive training demonstrated a reduction in repeat ankle sprains (RR = 0.64, 95% CI = 0.51, 0.81; NNT = 13, 95% CI = 7, 100). Proprioceptive training as a primary preventive measure demonstrated significant results (RR = 0.57, 95% CI = 0.34, 0.97; NNT = 33, 95% CI = 16, 1000).

CONCLUSIONS

  Proprioceptive training programs were effective in reducing the incidence rates of ankle sprains in the athletic population, including those with and those without a history of ankle sprains.

Balance Training Programs in Athletes - a Systematic Review

It has become almost routine practice to incorporate balance exercises into training programs for athletes from different sports. However, the type of training that is most efficient remains unclear, as well as the frequency, intensity and duration of the exercise that would be most beneficial have not yet been determined. The following review is based on papers that were found through computerized searches of PubMed and SportDiscus from 2000 to 2016. Articles related to balance training, testing, and injury prevention in young healthy athletes were considered. Based on a Boolean search strategy the independent researchers performed a literature review. A total of 2395 articles were evaluated, yet only 50 studies met the inclusion criteria. In most of the reviewed articles, balance training has proven to be an effective tool for the improvement of postural control. It is difficult to establish one model of training that would be appropriate for each sport discipline, including its characteristics and demands. The main aim of this review was to identify a training protocol based on most commonly used interventions that led to improvements in balance. Our choice was specifically established on the assessment of the effects of balance training on postural control and injury prevention as well as balance training methods. The analyses including papers in which training protocols demonstrated positive effects on balance performance suggest that an efficient training protocol should last for 8 weeks, with a frequency of two training sessions per week, and a single training session of 45 min. This standard was established based on 36 reviewed studies.

Prevention, treatment, and rehabilitation of anterior cruciate ligament injuries in children

As more children and adolescents participate in competitive organized sports, there has been an increase in the reported incidence of anterior cruciate ligament (ACL) injuries in these age groups. ACL injuries in skeletally immature athletes present a challenge, as reconstruction must preserve the physis of the distal femur and of the proximal tibia to avoid growth disturbances. Historically, a skeletally immature athlete with an ACL injury was treated with a brace and activity modification until skeletal maturity, with ACL reconstruction being performed at that time in the “non-copers” who experienced instability. More recently, evidence has shown that delayed reconstruction may lead to increased damage to the meniscus and articular cartilage. As a result, early reconstruction is favored to protect the meniscus and allow continued physical activity. While adolescents at or those near skeletal maturity may be treated with standard reconstruction techniques, they may result in growth disturbances in younger athletes with significant growth remaining. In response to the growing need for ACL reconstruction techniques in skeletally immature individuals, physeal-sparing and physeal-respecting reconstruction techniques have been developed. In addition to the advancements in surgical technique, ACL injury prevention has also gained attention. This growing interest in ACL prevention is in part related to the high risk of ACL re-tear, either of the ACL graft or of the contralateral ACL, in children and adolescents. Recent reports indicate that well-designed neuromuscular training programs may reduce the risk of primary and subsequent ACL injuries.