Anterior cruciate ligament prevention strategies: are they effective in young athletes - current concepts and review of literature

Association of Smokeless Tobacco Use With Perioperative Complications and Revision Surgery After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Tobacco use is a known modifiable risk factor for postoperative complications and revision surgery after anterior cruciate ligament reconstruction (ACLR). Previous studies focus on tobacco as a broad categorization of traditional smoking, smokeless tobacco, and other forms of nicotine use. It is unclear if differences in the type of nicotine used lead to similar adverse outcomes after ACLR.

PURPOSES

To (1) assess the incidence of postoperative complications among ACLR patients who use smokeless tobacco and (2) compare these outcomes with those of patients who do not use tobacco and those who smoke tobacco.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective cohort study utilizing the PearlDiver database was conducted. Patients undergoing primary ACLR with a minimum 2-year follow-up were included. Smokeless tobacco users (n = 898), cigarette smokers (n= 22,062), and non-tobacco users (n= 207,462) were matched based on patient variables and comorbidities. Postoperative complications within 90 days of surgery and subsequent knee surgery within 2 years were compared among groups. Multivariable logistic regressions were used to control for confounding variables.

RESULTS

Compared with nonusers, smokeless tobacco users demonstrated an increased risk of pneumonia (odds ratio [OR], 3.36; 95% CI, 1.41-7.90), acute kidney injury (OR, 12.7; 95% CI, 3.77-52.8), and emergency department (ED) utilization (OR, 6.29; 95% CI, 3.70-10.9) within 90 days of the ACLR. Additionally, smokeless tobacco users had an increased risk of ACLR (OR, 4.75; 95% CI, 3.60-6.26) and meniscal surgery (OR, 2.89; 95% CI, 2.23-3.73) within 2 years. When compared with cigarette smokers, smokeless tobacco users showed an increased risk of pneumonia (OR, 3.25; 95% CI, 1.33-7.78), acute kidney injury (OR, 7.63; 95% CI, 2.72-22.5), and ED visits (OR, 1.55; 95% CI, 1.26-1.90) within 90 days and subsequent ACLR (OR, 4.81; 95% CI, 3.58-6.47) and meniscal surgery (OR, 3.23; 95% CI, 2.45-4.26) within 2 years.

CONCLUSION

Smokeless tobacco use was associated with an increased risk of medical complications, ED utilization, and subsequent procedures compared with nonuser controls and traditional smokers. These findings highlight the importance of considering specific forms of tobacco use in preoperative screening for patients undergoing ACLR.

Effects of Early Sport Specialization on Injury Load Management and Athletic Success of National Basketball Association Players

Background

The effects of early sport specialization on professional athletes' resilience in handling increased workloads and athletic success have not been fully described.

Hypothesis

National Basketball Association (NBA) players who were multisport athletes during high school would be able to withstand higher workloads with lower injury rates and have more athletic success compared with their single-sport peers.

Study Design

Descriptive epidemiology study.

Methods

Included were first-round NBA draft picks from 2013 to 2023 who had played ≥1 game in their first 3 seasons after being drafted. Athletes who had participated in ≥1 high school sports in addition to basketball were classified as multisport athletes, while those who had only played basketball were classified as single-sport athletes. For each player's first 3 NBA seasons, workload data (number of games played and distance traveled per game/season in meters), injury history, statistical performance (player efficiency rating), and end-of-season award history were collected through the official NBA advanced statistics database and through publicly available records.

Results

Overall, 318 athletes were included, of whom 87 (27.4%) were multisport and 231 (72.6%) were single-sport. During their first 3 seasons combined, multisport athletes played in significantly more games (148.9 ± 67.1 vs 125.8 ± 63.8; P < .01), traveled greater total distances (133,183.9 ± 239,923.0 m vs 73,879.5 ± 165,093.9 m; P < .01), and had a significantly lower percentage of games missed due to injury (13.5% vs 16.9%; P < .001) compared with single-sport athletes. There was a significant correlation between increased workload (total distance traveled) and number of injuries in single-sport athletes (ρ = 0.37; P < .001) but not in multisport athletes (ρ = 0.14; P = .20). Last, multisport players had a significantly higher player efficiency rating (12.8 ± 11.6 vs 10.5 ± 5.1; P < .05) and award achievement likelihood (40.2% vs 19.0%; P < .001).

Conclusion

NBA players who had participated in multiple sports during high school demonstrated an ability to withstand higher workloads while having fewer games missed due to injury when compared with players who had only played basketball. Furthermore, athletes who delayed sport specialization had greater statistical and award success in their professional careers than those who focused on early single-sport specialization.

Comparative efficacy and safety of different surgical approaches for the treatment of anterior cruciate ligament injury: a Bayesian network meta-analysis protocol

INTRODUCTION

Anterior cruciate ligament (ACL) rupture can be treated surgically or non-surgically, with several surgical interventions available at present. However, the comparatively effective surgical intervention with relatively fewer side effects remains unknown. This study aims to fill in this gap by conducting a Bayesian network meta-analysis (NMA) and provide a theoretical basis for the clinical application.

METHOD AND ANALYSIS

We will perform a Bayesian NMA and will include randomised controlled trials (RCTs) published in English or Chinese that compare surgical intervention (ie, standard ACL reconstruction, ACL remnant-preserving reconstruction and ACL repair with suture augmentation to conservative therapy or studies that compare one surgical intervention to another for the symptom relief and function recovery of patients with ACL rupture. Primary outcome will be the proportion of patients with symptomatic and functional improvement measured by the Knee Injury and Osteoarthritis Outcome Score before and 6 months after treatment, with scores ranging from 0 (worst) to 100 (best). Secondary outcomes will be knee-specific quality of life (ACL QoL), return to activity and level of sport participation (Tegner or modified Tegner score), health-related QoL (EuroQol Group 5-Dimension 5-Level, EQ-5D-5L), resource use, intervention-related complications and patient satisfaction. We have developed search strategies for PubMed, Embase, the Cochrane Library and Web of Science, retrieving RCTs that meet the inclusion criteria from database inception to 1 December 2023. The methodological quality of the included RCTs will be assessed based on the Cochrane risk of bias table. The relative ranking probability of the best intervention will be estimated using the surface under the cumulative ranking curve. The Bayesian NMA will be conducted by using WinBUGS V.1.4.3. The Grading of Recommendations Assessment, Development and Evaluation approach will be applied to determine our confidence in an overall treatment ranking from the NMA.

ETHICS AND DISSEMINATION

Ethical approval for this study is not required because no private or confidential patient data will be used in this study. Findings of this study would be disseminated through the publication in a peer-reviewed medical journal.

PROSPERO REGISTRATION NUMBER

CRD42023437115.

Development of a Cutting Technique Modification Training Program and Evaluation of its Effects on Movement Quality and Cutting Performance in Male Adolescent American Football Players

This study developed a cutting technique modification training program and investigated its effects on cutting performance and movement quality in adolescent American football players. For six weeks, an intervention group (IG) of 11 players participated in 25 min cutting technique modification training sessions integrated into team training twice a week, while a control group (CG) of 11 players continued their usual team training. Movement quality was assessed by evaluating 2D high-speed videos, obtained during preplanned 45° and 90° cutting tests, using the Cutting Movement Assessment Score (CMAS) qualitative screening tool. Cutting performance was assessed based on change of direction deficit (CODD). Significant interaction effects of time × group were found for CMAS in 45° and 90° cuttings (p < 0.001, ηp2 = 0.76, p < 0.001, ηp2 = 0.64, respectively), with large improvements in the IG (p < 0.001, g = -2.16, p < 0.001, g = -1.78, respectively) and deteriorations in the CG for 45° cuttings (p = 0.002, g = 1.15). However, no statistically significant differences in CODD were observed pre-to-post intervention. The cutting technique modification training was effective at improving movement quality without impairing cutting performance, and it can be used by practitioners working with adolescent athletes.

Can Wearable Sensors Provide Accurate and Reliable 3D Tibiofemoral Angle Estimates during Dynamic Actions?

The ability to accurately measure tibiofemoral angles during various dynamic activities is of clinical interest. The purpose of this study was to determine if inertial measurement units (IMUs) can provide accurate and reliable angle estimates during dynamic actions. A tuned quaternion conversion (TQC) method tuned to dynamics actions was used to calculate Euler angles based on IMU data, and these calculated angles were compared to a motion capture system (our "gold" standard) and a commercially available sensor fusion algorithm. Nine healthy athletes were instrumented with APDM Opal IMUs and asked to perform nine dynamic actions; five participants were used in training the parameters of the TQC method, with the remaining four being used to test validity. Accuracy was based on the root mean square error (RMSE) and reliability was based on the Bland-Altman limits of agreement (LoA). Improvement across all three orthogonal angles was observed as the TQC method was able to more accurately (lower RMSE) and more reliably (smaller LoA) estimate an angle than the commercially available algorithm. No significant difference was observed between the TQC method and the motion capture system in any of the three angles (p < 0.05). It may be feasible to use this method to track tibiofemoral angles with higher accuracy and reliability than the commercially available sensor fusion algorithm.

Riding a Mechanical Scooter from the Inconvenient Side Promotes Muscular Balance Development in Children

Mechanical scooter riding is a popular physical activity among children, but little is known about the differences in muscle loading between the dominant and non-dominant sides during this activity. The objective of this study was to identify the muscle activation patterns in children's dominant and non-dominant legs as they rode scooters on the convenient and inconvenient sides. The study included nine healthy children aged 6-8. The participants rode 20 m on a mechanical scooter at a self-selected pace using both the convenient and inconvenient sides. Electromyography was used to measure the muscle activity in the dominant and non-dominant legs during the pushing and gliding phases. A 20 m sprint run was used as a control exercise to estimate the typical differences in muscle activation between the dominant and non-dominant legs. In the pushing phase, the symmetry index for five of the eight analyzed muscles exceeded 50% (p < 0.05); four of these muscles were more active in the pushing leg, and one was more active in the standing leg. In the gliding phase, four muscles were more active in the standing leg, and one was more active in the pushing leg (p < 0.05). Upon observing children who changed sides while riding a scooter, it was found that the pattern of muscle activation displayed a reverse trend that resembled the initial pattern. Our study indicated notable differences in muscle activity patterns between the dominant and non-dominant sides of individual leg muscles during children's scooter riding. These patterns were reversed when children switched sides on the scooter. These findings suggest that using both legs and switching sides while riding a scooter may be a viable strategy for promoting balanced muscular development.

Evidence for isokinetic and functional testing in return to sport decisions following ACL surgery

The rupture and reconstruction of the anterior cruciate ligament (ACL) of the knee are associated with an increased risk of functional instability, a reduction in sports performance, and a higher risk of future additional injuries. Competitive athletes who participate in sports that require pivoting, cutting, and jumping are at particularly high risk for ACL rupture. The return to sport progression continuum after surgery includes sports-specific rehabilitation, evaluation of strength and function, gradual participation in exercise training with progressively challenging activities in the field of play, participation in sports at a lower level, and finally a return to preinjury-level sports competition. This narrative review evaluates the evidence that supports the use of quadriceps and hamstrings isokinetic strength testing and sports-specific functional skills assessments to evaluate progress with rehabilitation after ACL surgery. Strength evaluations, hop tests, agility tests, and the limb symmetry index are described, as well as the associations of quadriceps and hamstrings muscle strength and functional test results with successful return to sports and the risk of ACL graft rupture and contralateral knee injuries. Suggestions for future research directions are presented including the importance of presurgery testing, standardization of test batteries, and comparison of test results with normative data.

Prevention of Non-Contact Anterior Cruciate Ligament Injuries among Youth Female Athletes: An Umbrella Review

Anterior cruciate ligament (ACL) injuries account for a large percentage of knee injuries, disproportionately affecting female athletes. To help health professionals stay current, we performed an umbrella review to evaluate the effectiveness of ACL injury prevention programs in reducing non-contact ACL injury rates, determine the effective components within interventions, and provide clinical recommendations. Twelve databases (Medline, Embase, Cochrane Database of Systematic Reviews, SPORTDiscus, Cumulative Index to Nursing and Allied Health Literature, PEDro, Web of Science Core Collection, Epistemonikos, TRIP, BC Guidelines and Protocols, CPG Infobase, ProQuest Dissertations and Theses Global) were searched in May 2021 to identify relevant systematic reviews and meta-analyses. Four databases were searched again in September 2021 to identify recent primary literature. Non-contact ACL injury data were extracted to calculate incidence rate ratios (IRRs) and these were combined using an inverse variance random-effects model. A qualitative assessment of included reviews was performed. The methodological quality of the studies was assessed using a Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) or Cochrane Risk-of-Bias Tool for Randomized Trials (RoB 2). Sixteen reviews and two primary studies met the inclusion criteria. Across 11 primary studies, prevention programs were effective in reducing non-contact ACL injuries by 64% (IRR = 0.36 (95% CI: 0.18-0.70)). A multi-faceted exercise program, beginning in the pre-season and containing at least three exercise types, may be beneficial in reducing ACL injury risk.

Effects and Dose-Response Relationship of Balance Training on Balance Performance in Youth: A Systematic Review and Meta-Analysis

BACKGROUND

Effects and dose-response relationships of balance training on measures of balance are well-documented for healthy young and old adults. However, this has not been systematically studied in youth.

OBJECTIVES

The objectives of this systematic review and meta-analysis were to quantify effects of balance training (BT) on measures of static and dynamic balance in healthy children and adolescents. Additionally, dose-response relations for BT modalities (e.g. training period, frequency, volume) were quantified through the analysis of controlled trials.

DATA SOURCES

A computerized systematic literature search was conducted in the electronic databases PubMed and Web of Science from January 1986 until June 2017 to identify articles related to BT in healthy trained and untrained children and adolescents.

STUDY ELIGIBILITY CRITERIA

A systematic approach was used to evaluate articles that examined the effects of BT on balance outcomes in youth. Controlled trials with pre- and post-measures were included if they examined healthy youth with a mean age of 6-19 years and assessed at least one measure of balance (i.e. static/dynamic steady-state balance, reactive balance, proactive balance) with behavioural (e.g. time during single-leg stance) or biomechanical (e.g. centre of pressure displacements during single-leg stance) test methods.

STUDY APPRAISAL AND SYNTHESIS METHODS

The included studies were coded for the following criteria: training modalities (i.e. training period, frequency, volume), balance outcomes (i.e. static and dynamic balance) as well as chronological age, sex (male vs. female), training status (trained vs. untrained), setting (school vs. club), and testing method (biomechanical vs. physical fitness test). Weighted mean standardized mean differences (SMD_wm) were calculated using a random-effects model to compute overall intervention effects relative to active and passive control groups. Between-study heterogeneity was assessed using I² and χ² statistics. A multivariate random effects meta-regression was computed to explain the influence of key training modalities (i.e. training period, training frequency, total number of training sessions, duration of training sessions, and total duration of training per week) on the effectiveness of BT on measures of balance performance. Further, subgroup univariate analyses were computed for each training modality. Additionally, dose-response relationships were characterized independently by interpreting the modality specific magnitude of effect sizes. Methodological quality of the included studies was rated with the help of the Physiotherapy Evidence Database (PEDro) Scale.

RESULTS

Overall, our literature search revealed 198 hits of which 17 studies were eligible for inclusion in this systematic review and meta-analysis. Irrespective of age, sex, training status, sport discipline and training method, moderate to large BT-related effects were found for measures of static (SMD_wm = 0.71) and dynamic (SMD_wm = 1.03) balance in youth. However, our subgroup analyses did not reveal any statistically significant effects of the moderator variables age, sex, training status, setting and testing method on overall balance (i.e. aggregation of static and dynamic balance). BT-related effects in adolescents were moderate to large for measures of static (SMD_wm = 0.61) and dynamic (SMD_wm = 0.86) balance. With regard to the dose-response relationships, findings from the multivariate random effects meta-regression revealed that none of the examined training modalities predicted the effects of BT on balance performance in adolescents (R² = 0.00). In addition, results from univariate analysis have to be interpreted with caution because training modalities were computed as single factors irrespective of potential between-modality interactions. For training period, 12 weeks of training achieved the largest effect (SMDwm = 1.40). For training frequency, the largest effect was found for two sessions per week (SMDwm = 1.29). For total number of training sessions, the largest effect was observed for 24-36 sessions (SMDwm = 1.58). For the modality duration of a single training session, 4-15 min reached the largest effect (SMDwm = 1.03). Finally, for the modality training per week, a total duration of 31-60 min per week (SMDwm = 1.33) provided the largest effects on overall balance in adolescents. Methodological quality of the studies was rated as moderate with a median PEDro score of 6.0.

LIMITATIONS

Dose-response relationships were calculated independently for training modalities (i.e. modality specific) and not interdependently. Training intensity was not considered for the calculation of dose-response relationships because the included studies did not report this training modality. Further, the number of included studies allowed the characterization of dose-response relationships in adolescents for overall balance only. In addition, our analyses revealed a considerable between-study heterogeneity (I² = 66-83%). The results of this meta-analysis have to be interpreted with caution due to their preliminary status.

CONCLUSIONS

BT is a highly effective means to improve balance performance with moderate to large effects on static and dynamic balance in healthy youth irrespective of age, sex, training status, setting and testing method. The examined training modalities did not have a moderating effect on balance performance in healthy adolescents. Thus, we conclude that an additional but so far unidentified training modality may have a major effect on balance performance that was not assessed in our analysis. Training intensity could be a promising candidate. However, future studies are needed to find appropriate methods to assess BT intensity.

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.

Pediatric Anterior Cruciate Ligament Reconstruction

The rate of anterior cruciate ligament (ACL) ruptures diagnosed among the pediatric and adolescent population is increasing. The rise in ACL injuries may be attributed to earlier sports specialization, year-round sports participation, increased awareness, and improved ability to diagnose the injury. Treatment options for pediatric or adolescent ACL injuries include nonoperative conservative treatment, ACL repair, or various techniques for ACL reconstruction. The best course of treatment for ACL rupture in young patients continues to be debated. Anterior cruciate ligament reconstruction with autograft is currently the gold standard and has been shown to be successful in restoring joint stability. This article reviews predisposing factors, common mechanisms, diagnostic procedures, and treatments for ACL rupture in adolescent patients, with a focus on using quadriceps patellar tendon autograft. [Orthopedics. 2018; 41(3):129-134.].

The Effects of Playing Multiple High School Sports on National Basketball Association Players' Propensity for Injury and Athletic Performance

BACKGROUND

Athletes who specialize in their sport at an early age may be at risk for burnout, overuse injury, and reduced attainment of elite status. Timing of sport specialization has not been studied in elite basketball athletes.

HYPOTHESIS

National Basketball Association (NBA) players who played multiple sports during adolescence would be less likely to experience injury and would have higher participation rates in terms of games played and career length compared with single-sport athletes.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

First-round draft picks from 2008 to 2015 in the NBA were included in the study. From publically available records from the internet, the following data were collected for each athlete: participation in high school sports, major injuries sustained in the NBA, percentage of games played in the NBA, and whether the athlete was still active in the NBA. Athletes who participated in sports in addition to basketball during high school were defined as multisport athletes and were compared with athletes who participated only in basketball in high school.

RESULTS

Two hundred thirty-seven athletes were included in the study, of which 36 (15%) were multisport athletes and 201 (85%) were single-sport athletes in high school. The multisport cohort played in a statistically significantly greater percentage of total games (78.4% vs 72.8%; P < .001). Participants in the multisport cohort were less likely to sustain a major injury during their career (25% vs 43%, P = .03). Finally, a greater percentage of the multisport athletes were active in the league at time of data acquisition, indicating increased longevity in the NBA (94% vs 81.1%; P = .03).

CONCLUSION

While a minority of professional basketball athletes participated in multiple sports in high school, those who were multisport athletes participated in more games, experienced fewer major injuries, and had longer careers than those who participated in a single sport. Further research is needed to determine the reasons behind these differences.

Trends in Pediatric and Adolescent Anterior Cruciate Ligament Injuries in Victoria, Australia 2005-2015

Anterior cruciate ligament (ACL) injuries in children and adolescents have been the focus of recent media attention and parental concern, given their potential for adverse long-term health outcomes and healthcare costs. However, there is limited formal evidence on trends in the incidence of ACL injuries in children. This study utilizes the Victorian Admitted Episodes Dataset (VAED) to characterize epidemiologic trends of hospital-admitted ACL injuries in those aged 5 to 14 years over a period of 10 years from 2005 to 2015. There was a total of 320 cases and the overall annual rate of ACL injuries increased by 147.8% from 2.74 per 100,000 population in 2005/2006 to 6.79 per 100,000 in 2014/2015. The majority (96.9%) of these injuries were in 10- to 14-year-olds. The main in-hospital procedure provided to over 80% of the hospitalized cases involved ACL reconstruction. Sporting activities accounted for 56.6% of ACL injuries. For females, over half (52.4%) of ACL injuries occurred whilst playing ball sports, compared to 35.4% of males. The large increase in ACL injuries in 5- to 14-year-olds in the state of Victoria, Australia over a 10-year period indicates they are a significant and emerging health burden. Population-wide ACL prevention policies are required to halt these trends. Cost effective prevention programs that involve neuromuscular training must be implemented in schools and junior sports teams.

Biomechanical Effects of an Injury Prevention Program in Preadolescent Female Soccer Athletes

BACKGROUND

Anterior cruciate ligament (ACL) injuries are common, and children as young as 10 years of age exhibit movement patterns associated with an ACL injury risk. Prevention programs have been shown to reduce injury rates, but the mechanisms behind these programs are largely unknown. Few studies have investigated biomechanical changes after injury prevention programs in children. Purpose/Hypothesis: To investigate the effects of the F-MARC 11+ injury prevention warm-up program on changes to biomechanical risk factors for an ACL injury in preadolescent female soccer players. We hypothesized that the primary ACL injury risk factor of peak knee valgus moment would improve after training. In addition, we explored other kinematic and kinetic variables associated with ACL injuries.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 51 female athletes aged 10 to 12 years were recruited from soccer clubs and were placed into an intervention group (n = 28; mean [±SD] age, 11.8 ± 0.8 years) and a control group (n = 23; mean age, 11.2 ± 0.6 years). The intervention group participated in 15 in-season sessions of the F-MARC 11+ program (2 times/wk). Pre- and postseason motion capture data were collected during preplanned cutting, unanticipated cutting, double-leg jump, and single-leg jump tasks. Lower extremity joint angles and moments were estimated using OpenSim, a biomechanical modeling system.

RESULTS

Athletes in the intervention group reduced their peak knee valgus moment compared with the control group during the double-leg jump (mean [±standard error of the mean] pre- to posttest change, -0.57 ± 0.27 %BW×HT vs 0.25 ± 0.25 %BW×HT, respectively; P = .034). No significant differences in the change in peak knee valgus moment were found between the groups for any other activity; however, the intervention group displayed a significant pre- to posttest increase in peak knee valgus moment during unanticipated cutting ( P = .044). Additional analyses revealed an improvement in peak ankle eversion moment after training during preplanned cutting ( P = .015), unanticipated cutting ( P = .004), and the double-leg jump ( P = .016) compared with the control group. Other secondary risk factors did not significantly improve after training, although the peak knee valgus angle improved in the control group compared with the intervention group during unanticipated cutting ( P = .018).

CONCLUSION

The F-MARC 11+ program may be effective in improving some risk factors for an ACL injury during a double-leg jump in preadolescent athletes, most notably by reducing peak knee valgus moment.

CLINICAL RELEVANCE

This study provides motivation for enhancing injury prevention programs to produce improvement in other ACL risk factors, particularly during cutting and single-leg tasks.

Anterior cruciate ligament reconstruction in skeletally immature patients

The management of pediatric patients with an anterior cruciate ligament (ACL) tear can be a challenging endeavor for physicians, athletic trainers, coaches, and parents alike. In particular, the significant longitudinal growth that arises from the physes about the knee creates a unique set of circumstances that must be considered in this patient population. The purpose of this review is to provide a summary of the most recent current literature for the management of skeletally immature patients with an ACL tear.

Evaluation of the interaction between contact force and decision making on lower extremity biomechanics during a side-cutting maneuver

INTRODUCTION

The purposes of this study were (1) to compare the effect between contact force [first and second ground reaction force (GRF)] and decision making (anticipation vs unanticipation) on lower extremity biomechanics during a side-cutting maneuver in young soccer players; and (2) to identify which condition is more vulnerable to biomechanical risk factors of the anterior cruciate ligament (ACL) injury.

MATERIALS AND METHODS

Sixteen young, male middle school soccer players with right leg dominance participated in this study. Three-dimensional motion analysis featuring GRF and electromyography (EMG) of the right leg was used during the stance phase of the side-cutting maneuver. Kinematics, kinetics, and EMG data for each athlete were analyzed and averaged for three successful anticipated and unanticipated side-cutting maneuvers.

RESULTS

GRF was smaller and muscle activities were lower in most muscle groups in the first peak than that of the second peak. More flexion and internal rotational angles of the hip joint were observed in the unanticipated first peak that that of the second peak. Lesser flexion angle and moment of the knee joint observed in the first peak than that of the second peak, and abduction moment was increased after the unanticipation.

CONCLUSION

The GRF and muscle activities were smaller in the first peak than those in the second peak; however, first peak showed a closer association with biomechanical risk factors of the ACL injury. There were some interactions between contact force and decision making and unanticipation made the first peak more risky to the ACL injury.

ACL injury in football: a literature overview of the prevention programs

BACKGROUND

The ACL prevention programs are addressed to the control and/or modification of the so-called "modifiable risk factors". All these programs focus on different intervention strategies aimed to decrease the ACL injury risk, particularly in female athletes population.

PURPOSE

To furnish an overview of the most used ACL injury prevention program through a narrative review.

CONCLUSION

In literature there are many reports on prevention programs whose common denominator is the proper alignment of the lower limb joints and proper motor control during movements that are considered at risk for ACL integrity, as the landing phase after a jump. Nevertheless, some programs would appear more effective than others. In any cases a major problem remains the lack of sufficient compliance in respect of prevention programs. Finally, it is important to remember that the ethiology of ACL injuries is multifactorial. For this reason a prevention program able to prevent all the risk situations is utopian.

STUDY DESIGN

Narrative review.

Exercise-based injury prevention in child and adolescent sport: a systematic review and meta-analysis

BACKGROUND

The promotion of sport and physical activity (PA) for children is widely recommended to support a healthy lifestyle, but being engaged in sport bears the risk of sustaining injuries. Injuries, in turn, can lead to a reduction in current and future involvement in PA and, therefore, may negatively affect future health as well as quality of life. Thus, sports injury prevention is of particular importance in youth.

OBJECTIVE

The aim of this systematic review was to quantify the effectiveness of exercise-based injury prevention programs in child and adolescent sport in general, and with respect to different characteristics of the target group, injury prevention program, and outcome variables.

DATA SOURCES

An Internet-based literature search was conducted in six databases (CINAHL, Cochrane, EMBASE, ISI Web of Science, PubMed, SPORTDiscus) using the following search terms with Boolean conjunction: (sport injur* OR athletic injur* OR sport accident*) AND (prevent* OR prophylaxis OR avoidance) AND (child* OR adolescent OR youth).

STUDY SELECTION

Randomized controlled trials and controlled intervention studies in organized sport, published in English in a peer-reviewed journal, analyzing the effects of an exercise-based injury prevention program in athletes younger than 19 years of age.

DATA EXTRACTION

Two reviewers evaluated eligibility and methodological quality. Main outcome extracted was the rate ratio (RR). Statistical analyses were conducted using the inverse-variance random effects model.

RESULTS

Twenty-one trials, conducted on a total of 27,561 athletes (median age 16.7 years [range 10.7-17.8]), were included. The overall RR was 0.54 (95% CI 0.45-0.67) [p < 0.001]. Girls profited more from injury prevention than boys (p = 0.05). Both prevention programs with a focus on specific injuries (RR 0.48 [95% CI 0.37-0.63]) and those aiming at all injuries (RR 0.62 [95% CI 0.48-0.81]) showed significant reduction effects. Pre-season and in-season interventions were similarly beneficial (p = 0.93). Studies on programs that include jumping/plyometric exercises showed a significant better (p = 0.002) injury preventive effect (RR 0.45 [95% CI 0.35-0.57], Z = 6.35, p < 0.001) than studies without such exercises (RR 0.74 [95% CI 0.61-0.90], Z = 3.03, p = 0.002).

CONCLUSIONS

The results provide good evidence and clearly demonstrate beneficial effects of exercise-based injury prevention programs in youth sports as they can result in statistically significant and practically relevant injury reduction. In particular, multimodal programs including jumping/plyometric exercises can be recommended. However, there is a considerable lack of data for children (under 14 years of age) and for individual sports in general. Future research should include these groups and focus on the effect of specific exercises and compliance.

Consequences of single sport specialization in the pediatric and adolescent athlete

Pediatric and adolescent sports participation has increased with a concomitant increase in injuries. Sports have transitioned from recreational to deliberate, structured activities wherein success is determined by achievement of 'elite' status. This has led to specialization in a single sport with intensive, repetitive activity at younger ages causing physical and emotional consequences, particularly true for the growing athlete who is particularly susceptible to injury. Clinicians caring for this population must understand the epidemiology of youth sports specialization, the unique physiology/structure of this age group, and the potential physical and emotional consequences.

Surgical options for anterior cruciate ligament reconstruction in the young child

PURPOSE OF REVIEW

To review the most recent literature on the epidemiology, diagnosis, treatment, and outcomes of pediatric anterior cruciate ligament injury.

RECENT FINDINGS

There is an increasing prevalence of anterior cruciate ligament injuries in pediatric and adolescent athletes, and nonoperative management of these injuries results in worse outcomes than surgical reconstruction. Prevention exercise protocols are cost-effective in preventing this injury in adolescent athletes. A number of techniques are currently in practice that address anterior cruciate ligament injuries in the skeletally immature, but there is no consensus on the optimal technique.

SUMMARY

The reported clinical outcomes from anterior cruciate ligament reconstruction in young patients are favorable.

Effect of Anticipation on Lower Extremity Biomechanics During Side- and Cross-Cutting Maneuvers in Young Soccer Players

BACKGROUND

Less mature athletes exhibit biomechanical parameters during cutting maneuvers that may place these athletes at greater risk for injury than their more mature counterparts, especially if the maneuvers are unanticipated. However, most studies on risk factors for anterior cruciate ligament (ACL) injury have focused on neuromuscular and knee kinematic differences between the sexes, not on the biomechanical parameters between specific sporting maneuvers.

HYPOTHESES

(1) Anticipation will have a greater effect than the type of cutting maneuver (side- vs cross-cutting) in terms of the biomechanical risk factors for ACL injuries, and (2) the biomechanical risk factors will be different between the 2 types of maneuvers.

STUDY DESIGN

Controlled laboratory study.

METHODS

Thirty-seven young, male middle school soccer players participated in this study. Three-dimensional motion analysis featuring ground-reaction force and electromyography of the right leg was used. Kinematics, kinetics, and electromyography data for each athlete were analyzed during anticipated and unanticipated side- and cross-cutting maneuvers. The differences between anticipated and unanticipated states as well as between side- and cross-cutting maneuvers were calculated and compared.

RESULTS

After unanticipated side-cutting, the time to peak ground-reaction force was longer and peak values were smaller compared with anticipated side-cutting. Flexion, valgus, and internal rotations in the knee joint were larger, and greater flexion and valgus moments were observed. The vastus lateralis and vastus medialis showed lower activity, and the lateral gastrocnemius showed higher activity after unanticipated side-cutting maneuvers. With unanticipated cross-cutting, the time to peak ground-reaction force was longer and peak values were smaller compared with anticipated cross-cutting, and the lateral gastrocnemius showed higher activity. Differences in the peak values of the mediolateral and vertical forces were smaller in the cross-cutting maneuver than in side-cutting. Changes in flexion and adduction of the hip joint, flexion of the knee joint, and inversion of the ankle joint were larger during side-cutting.

CONCLUSION

Although there were some interactions between direction and anticipation, anticipating a cutting maneuver generally had a greater effect than the type of maneuver when there was no significant interaction.

CLINICAL RELEVANCE

Increases in the valgus angle and moment of the knee joint and higher lateral gastrocnemius activity during the late period showed an association with ACL injury risk factors during side-cutting, and higher lateral gastrocnemius activity during the early period showed an association with injury risk factors during cross-cutting.

The child and adolescent athlete: a review of three potentially serious injuries

The increased participation of children and adolescents in organized sports worldwide is a welcome trend given evidence of lower physical fitness and increased prevalence of overweight in this population. However, the increased sports activity of children from an early age and continued through the years of growth, against a background of their unique vulnerability to injury, gives rise to concern about the risk and severity of injury. Three types of injury–anterior cruciate ligament (ACL) injury, concussion, and physeal injury – are considered potentially serious given their frequency, potential for adverse long-term health outcomes, and escalating healthcare costs. Concussion is probably the hottest topic in sports injury currently with voracious media coverage and exploding research interest. Given the negative cognitive effects of concussion, it has the potential to have a great impact on children and adolescents during their formative years and potentially impair school achievement and, if concussion management is not managed appropriately, there can be long term negative impact on cognitive development and ability to resume sports participation. Sudden and gradual onset physeal injury is a unique injury to the pediatric population which can adversely affect growth if not managed correctly. Although data are lacking, the frequency of stress-related physeal injury appears to be increasing. If mismanaged, physeal injuries can also lead to long-term complications which could negatively affect ability to participate in sports. Management of ACL injuries is an area of controversy and if not managed appropriately, can affect long-term growth and recovery as well as the ability to participate in sports. This article considers the young athlete’s vulnerability to injury, with special reference to ACL injury, concussion, and physeal injury, and reviews current research on epidemiology, diagnosis, treatment, and prevention of these injury types. This article is intended as an overview of these injury types for medical students, healthcare professionals and researchers.

Prevention and screening programs for anterior cruciate ligament injuries in young athletes: a cost-effectiveness analysis

BACKGROUND

Anterior cruciate ligament (ACL) injuries are common among young athletes. Biomechanical studies have led to the development of training programs to improve neuromuscular control and reduce ACL injury rates as well as screening tools to identify athletes at higher risk for ACL injury. The purpose of this study was to evaluate the cost-effectiveness of these training methods and screening strategies for preventing ACL injuries.

METHODS

A decision-analysis model was created to evaluate three strategies for a population of young athletes participating in organized sports: (1) no training or screening, (2) universal neuromuscular training, and (3) universal screening, with neuromuscular training for identified high-risk athletes only. Risk of injury, risk reduction from training, and sensitivity and specificity of screening were based on published data from clinical trials. Costs of training and screening programs were estimated on the basis of the literature. Sensitivity analyses were performed on key model parameters to evaluate their effect on base case conclusions.

RESULTS

Universal neuromuscular training of all athletes was the dominant strategy, with better outcomes and lower costs compared with screening. On average, the implementation of a universal training program would save $100 per player per season, and would reduce the incidence of ACL injury from 3% to 1.1% per season. Screening was not cost-effective within the range of reported sensitivity and specificity values.

CONCLUSIONS AND CLINICAL RELEVANCE

Given its low cost and ease of implementation, neuromuscular training of all young athletes represents a cost-effective strategy for reducing costs and morbidity from ACL injuries. While continued innovations on inexpensive and accurate screening methods to identify high-risk athletes remain of interest, improving existing training protocols and implementing neuromuscular training into routine training for all young athletes is warranted.