Effects of a neuromuscular training program using external focus attention cues in male athletes with anterior cruciate ligament reconstruction: a randomized clinical trial

The Effect of Verbal Combined Focus of Attention and Video Instruction Training on Knee Valgus and Landing Technique in Semiprofessional Female Athletes

Background

Current anterior cruciate ligament (ACL) injury prevention programs focus on integrating the athlete's cognitive and motor skills. A few studies examine the effectiveness of different types of attentional instructions on motor learning.

Purpose

To investigate the acute and first-week effects of combined focus of attention and video instructions given to female athletes with dynamic knee valgus (DKV) and landing technique.

Study Design

Controlled laboratory study.

Methods

A total of 30 athletes were randomized to (1) a verbal combined focus-instructed group (VFIG) (n = 10), (2) a video-instructed group (VIG) (n = 10), and (3) a control group (CG) (n = 10). DKV was assessed with frontal plane projection angle (FPPA) during the single-leg squat test, and landing technique was assessed with the Landing Error Scoring System (LESS) during drop vertical jump (DVJ) task. After pre-FPPA and pre-LESS values were recorded, 2 training blocks that contained 10 repetitions of the DVJ task in each were completed with group-specific instructions, and posttest measurements were taken immediately afterward and a week after as a retention test. Parametric tests were utilized due to the normal distribution of numerical descriptive features. Independent-sample t tests compared numerical features between groups, chi-square tests assessed categorical features, and mixed-order analysis of variance evaluated variables based on retention times, with Bonferroni correction applied and a significance threshold set at P < .05.

Results

Statistical improvement occurred in both VFIG and VIG intragroup FPPA assessment at posttest and retention test (respectively, P < .001; P < .001; P < .01). In the intergroup evaluation, FPPA showed superior improvement in VFIG at the posttest and retention test (P = .001; P < .01). In the intragroup evaluation, there was a statistical improvement in LESS values in both VFIG and VIG, at the posttest and retention test (respectively, P = .04; P < .001; P < .05), and VIG had superior improvement in the intragroup evaluation compared with VFIG. There was no statistically significant difference between LESS values in the intergroup evaluation (for all, P > .05). There was no significant difference in the CG tests (for all, P > .05).

Conclusion

Our study demonstrated that while both types of instructions were effective in improving knee valgus and landing technique, verbal combined focus instructions were superior in improving valgus. Future long-term studies will help in the understanding of the prevention of ACL injuries in female athletes.

Clinical Relevance

Considering that female athletes have a higher risk of ACL injury due to higher DKV values than men, the authors believe that combined verbal and video instructions are important in reducing the knee valgus value and improving the landing technique, thus possibly reducing the injury rate.

Registration

NCT06424886 (ClinicalTrials.gov identifier).

Verbal instructions for attentional focus influence the results of tests for return to sport after anterior cruciate ligament reconstruction

This cross-sectional study investigated the influence of attentional focus verbal instructions on test results for return to sport (RTS) after ACL-R. Sixty subjects (53 male and 7 female, age 27.52 ± 7.63 years, body mass 77.56 ± 12.41 kg, height 162.04 ± 43.90 cm, and surgery time 11.15 ± 4.55 months) were evaluated in the single hop test (SHT), 6 m timed hop test (6mTHT), and "T" agility test. Participants performed the tests following randomly determined verbal instructions that induced neutral focus (NF), internal focus (IF), and external focus (EF). EF increased hop distance in SHT compared to NF (p = 0.001, effect size = 0.57) and IF (p = 0.037, effect size = 0.57) and there was no difference between IF and NF (p = 0.418). In 6mTHT, NF and EF increase velocity compared to IF (p = 0.001, effect size = 0.49, p = 0.001, effect size = 0.49, respectively). In the "T" agility test, the NF increased velocity when compared to the EF (p = 0.001, effect size = 0.62) and the IF (p = 0.001, effect size = 0.62), without difference between IF and EF (p = 0.071). In summary, attentional focus in patients under ACL-R can influence hops and agility.

The Effect of Neurocognitive Training on Biomechanical Risk Factors Related to Anterior Cruciate Ligament Injury in Athletes: A Narrative Review

CONTEXT

The best current evidence supports the effectiveness of neuromuscular training in reducing the risk of injury; however, the rate of anterior cruciate ligament (ACL) injuries is still high. Neurocognitive training (NT) has successfully improved biomechanical risk factors, but they have been considered in only a few studies.

OBJECTIVE

To review the literature to determine the effect of NT on biomechanical risk factors related to ACL injury in athletes.

EVIDENCE ACQUISITION

We searched PubMed, Google Scholar, Scopus, Science Direct, and the Physiotherapy Evidence Database from inception to August 2011. We included randomized controlled trials that used motor learning approaches and injury prevention programs to investigate kinematic and kinetic risk factors related to ACL injury. The quality of each clinical trial study was evaluated by the Physiotherapy Evidence Database scale. The eligibility criteria were checked based on the PICOS (population, intervention, comparison, outcome, and study type) framework.

EVIDENCE SYNTHESIS

A total of 9 studies were included in the final analysis. Motor learning approaches include internal and external focus of attention, dual tasks, visual motor training, self-control feedback, differential learning, and linear and nonlinear pedagogy, combined with exercise programs. In most of the studies that used NT, a significant decrease in knee valgus; tibial abduction and external rotation; ground reaction force; and an increase in knee-, trunk-, hip-, and knee-flexion moment was observed.

CONCLUSION

In classical NT, deviation from the ideal movement pattern especially emphasizing variability and self-discovery processes is functional in injury prevention and may mitigate biomechanical risk factors of ACL injuries in athletes. Practitioners are advised to use sport-specific cognitive tasks in combination with neuromuscular training to simulate loads of the competitive environment. This may improve ACL injury risk reduction and rehabilitation programs.

Effectiveness of psychological intervention following anterior cruciate ligament reconstruction: A systematic review and meta-analysis

OBJECTIVE

To determine the effectiveness of psychological interventions in postoperative anterior cruciate ligament reconstruction (ACLR) compared to standard rehabilitation.

METHODS

The databases searched were PubMed, MEDLINE, Cochrane Central Register of Controlled Trials, PEDro, Cumulative Index to Nursing & Allied Health Literature, and EMBASE were searched from each database inception to May 2023 for published studies. The methodological quality was assessed with the Cochrane Risk of Bias Assessment (RoB 2.0) tool. The evidence quality was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation approach.

RESULTS

Six papers were included in the meta-analysis. Psychological intervention significantly improved Tampa Scale for Kinesiophobia at 3 months (Standard Mean Difference [SMD], -0.51. 95% Confidence Interval [CI], -0.85 to -0.17) and pain (Knee Injury and Osteoarthritis Outcome Score for Pain, Numeric Rating Scale, Visual Analog Scale) at 3 months (SMD, -0.92. 95%CI, -1.69 to -0.15) and at 6 months following ACLR (MD, -1.25. 95%CI, -1.82 to -0.68) when compared with the standard rehabilitation, according to very low-quality data. Self-efficacy and knee strength did not show significant differences.

CONCLUSION

Very low-quality evidence suggests that psychological intervention following ACLR yields better short-term outcomes compared to standard rehabilitation, with uncertainty about its clinically significant benefits over standard rehabilitation.

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.

A clinical practice review of therapeutic movement-based anterior cruciate ligament reconstruction return to sports bridge program: the biological, biomechanical and behavioral rationale

This clinical practice review describes the biological, biomechanical and behavioral rationale behind a return to sport bridge program used predominantly with non-elite, youth and adolescent high school and college athletes following anterior cruciate ligament (ACL) reconstruction. Post-physiotherapy, this program has produced outcomes that meet or exceed previous reports. With consideration for athletic identity and the Specific Adaptations to Imposed Demands (SAID) principle, the early program focus was on restoring non-impaired bilateral lower extremity joint mobility and bi-articular musculotendinous extensibility. Building on this foundation, movement training education, fundamental bilateral lower extremity strength and power, and motor learning was emphasized with use of external focus cues and ecological dynamics-social cognition considerations. Plyometric and agility tasks were integrated to enhance fast twitch muscle fiber recruitment, anaerobic metabolic energy system function, and fatigue resistance. The ultimate goal was to achieve the lower extremity neuromuscular control and activation responsiveness needed for bilateral dynamic knee joint stability. The rationale and conceptual basis of selected movement tasks and general philosophy of care concepts are described and discussed in detail. Based on the previously reported efficacy of this movement-based therapeutic exercise program we recommend that supplemental programs such as this become standard practice following release from post-surgical physiotherapy and before return to sports decision-making.

Biomechanical Assessment and Neuromuscular Training to Mitigate Risk of Reinjury After ACLR

Background

Reinjury rates following anterior cruciate ligament (ACL) reconstruction remain high, and the cause is often multifactorial. There is growing literature supporting asymmetric biomechanical deficits leading to increased risk of reinjury. Neuromuscular training during postoperative rehabilitation may mitigate risk of reinjury by addressing these biomechanical deficits.

Indications

Neuromuscular training is supported in the literature to reduce primary ACL injury risk and modify biomechanical risk factors. Incorporating neuromuscular training into postoperative rehabilitation following ACL reconstruction may reduce the risk of reinjury.

Technique Description

The Landing Error Scoring System, or LESS test, is an assessment tool utilized to detect biomechanical asymmetries following ACL reconstruction. Video analysis allows for observation of subtle biomechanical differences. Neuromuscular training programs help improve these deficits through stepwise gradual and individualized progressions that are specific to each patient's needs and desired athletic return.

Results

A patient who participates in neuromuscular training as a component of postoperative rehabilitation should demonstrate improvements in their individual biomechanical deficits at the completion of the program described.

Discussion/Conclusion

Biomechanical assessment following ACL reconstruction, such as the LESS test, can identify deficits that may increase risk of reinjury. Neuromuscular training following ACL reconstruction can address these deficits and potentially mitigate risk of reinjury.

Patient Consent Disclosure Statement

The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Every story has two sides: evaluating information processing and ecological dynamics perspectives of focus of attention in skill acquisition

Directing our focus of attention appropriately during task execution can benefit outcome performance, cognitive efficiency, and physiological efficiency. For instance, individuals may benefit from adopting an external focus of attention (i.e., by focusing attention on the effects of one's movements on the environment) over an internal focus of attention (e.g., focusing on one's body movements). However, accounts concerning the theoretical functioning of such effects have primarily relied on hierarchical information processing perspectives; far less consideration has been given to potentially alternative explanations based on ecological dynamics, instances where an internal focus may be desirable over an external focus, and the associated applied implications. Within the present review, we: (a) outline the most recent developments in attentional focus research; (b) evaluate similarities and differences between information processing and ecological dynamics explanations of the focus of attention effect; (c) provide practical recommendations; and (d) discuss future research avenues. In doing so, a case is made for an "Ecological Dynamics Account of Attentional Focus" to act as an alternative to information processing-based hypotheses.

Comparing the Effects of Differential and Visuo-Motor Training on Functional Performance, Biomechanical, and Psychological Factors in Athletes after ACL Reconstruction: A Randomized Controlled Trial

Variation during practice is widely accepted to be advantageous for motor learning and is, therefore, a valuable strategy to effectively reduce high-risk landing mechanics and prevent primary anterior cruciate ligament (ACL) injury. Few attempts have examined the specific effects of variable training in athletes who have undergone ACL reconstruction. Thereby, it is still unclear to what extent the variations in different sensor areas lead to different effects. Accordingly, we compared the effects of versatile movement variations (DL) with variations of movements with emphasis on disrupting visual information (VMT) in athletes who had undergone ACL reconstruction. Forty-five interceptive sports athletes after ACL reconstruction were randomly allocated to a DL group (n = 15), VT group (n = 15), or control group (n = 15). The primary outcome was functional performance (Triple Hop Test). The secondary outcomes included dynamic balance (Star Excursion Balance Test (SEBT)), biomechanics during single-leg drop-landing task hip flexion (HF), knee flexion (KF), ankle dorsiflexion (AD), knee valgus (KV), and vertical ground reaction force (VGRF), and kinesiophobia (Tampa Scale of Kinesiophobia (TSK)) assessed before and after the 8 weeks of interventions. Data were analyzed by means of 3 × 2 repeated measures ANOVA followed by post hoc comparison (Bonferroni) at the significance level of p ≤ 0.05. Significant group × time interaction effects, main effect of time, and main effect of group were found for the triple hop test and all eight directions, SEBT, HF, KF, AD, KV, VGRF, and TSK. There was no significant main effect of group in the HF and triple hop test. Additionally, significant differences in the triple hop test and the seven directions of SEBT, HF, KF, KV, VGRF, and TSK were found between the control group and the DL and VMT groups. Between group differences in AD and the medial direction of SEBT were not significant. Additionally, there were no significant differences between VMT and the control group in the triple hop test and HF variables. Both motor learning (DL and VMT) programs improved outcomes in patients after ACL reconstruction. The findings suggest that DL and VMT training programs lead to comparable improvements in rehabilitation.

Secondary Anterior Cruciate Ligament Injury Prevention Training in Athletes: What Is the Missing Link?

After reconstruction, the return to full competition rate of athletes is low, while the re-injury rate remains high despite the completion of a rehabilitation programme. Primary ACL prevention programmes are well developed, yet few research papers focus on secondary ACL injury prevention. The aim of current review is to determine if current ACL secondary prevention training has a positive influence on the re-injury rate, the clinical or functional outcomes, or the risk of re-injury in athletes. Studies investigating secondary prevention of ACL were searched in PubMed and EBSCOhost, followed by a review of the references in the identified articles. The existing evidence suggests that neuromuscular training, eccentric strengthening, and plyometric exercises may have a potential impact on improving biomechanical, functional, and psychological outcomes in athletes; however, the studies on the prevention of second ACL injury in athletes is scarce and inconclusive. Future research is needed to investigate the effectiveness of secondary ACL prevention in reducing the re-injury rates. (PROSPERO Registration number: CRD42021291308).

Kinesiophobia Is Associated with Peak Knee Abduction Angle during Jump Landing after ACL Reconstruction

INTRODUCTION

This study aimed to investigate the associations between kinesiophobia, knee abduction angle (KAA) during the first 100 ms of landing, and knee flexion excursion (KFE) in individuals 5-12 months after anterior cruciate ligament reconstruction (ACLR). We hypothesized that greater kinesiophobia would be associated with greater peak KAA and lesser KFE during landing on the ACLR limb, but not on the contralateral limb.

METHODS

Thirty-six participants between 14 and 35 yr old (females = 19, age = 19.9 ± 5.1 yr, height = 172.5 ± 9.4 cm, weight = 76.7 ± 20.0 kg, time since surgery =7.2 ± 1.7 months) were recruited from a sports medicine clinic at 5-12 months after primary unilateral ACLR. Participants completed the Tampa Scale of Kinesiophobia-11 (TSK-11) to measure kinesiophobia and three successful trials of a standard drop vertical jump task. A 10-camera three-dimensional motion capture system synchronized with two embedded force plate platforms was used to capture jump-landing kinematics. Separate stepwise linear regression models were used to examine the associations between kinesiophobia, peak KAA, and KFE on the ACLR and contralateral limbs after accounting for time since surgery and biological sex.

RESULTS

When accounting for time since surgery and biological sex, every 1-point increase on the TSK-11 (i.e., increase in kinesiophobia) associated with a 0.37° increase (i.e., a 7.1% increase) in ACLR limb KAA ( P = 0.02). Kinesiophobia was not associated with contralateral limb KAA, ACLR limb KFE, or contralateral limb KFE.

CONCLUSIONS

Higher kinesiophobia was related to greater amounts of peak KAA during landing in individuals 5-12 months post-ACLR. Modifying kinesiophobia may help to decrease KAA and lead to reduced secondary ACL injury risk. Future research should investigate feasible psychological interventions to reduce kinesiophobia and improve KAA in patients post-ACLR.

Comparison of proprioception recovery following anterior cruciate ligament reconstruction using an artificial graft versus an autograft

BACKGROUND

To compare proprioception recovery after anterior cruciate ligament reconstruction (ACLR) with a hamstring tendon autograft versus the artificial Ligament Advanced Reinforcement System (LARS).

MATERIAL AND METHODS

Forty patients (9 females, 31 males) with anterior cruciate ligament (ACL) rupture were enrolled in this prospective study. Patients were randomized to two groups, 1) ACLR using a hamstring tendon autograft (n = 20) or 2) ACLR using artificial LARS (n = 20). Proprioception was assessed with knee joint position sense (JPS) passive-passive test at 45° and 75° flexions, with the contralateral healthy knee as a control baseline to calculate the JPS error. Knee JPS absolute error was used as the main outcome variable and defined as the absolute difference between the reproduction and target angles.

RESULTS

JPS error in both groups at 3 months after ACLR was significantly higher than that at 12 months. However, no significant difference in JPS error was detected between the LARS and autograft groups at either 3 or 12 months after ACLR. Analyzing JPS data by grouping patients according to whether ACLR was performed more or less than 1 year following injury regardless of graft type showed a statistically significant difference between the groups at 3 months, but not at 12 months, after ACLR. Patients receiving the graft within 1 year of injury had a lower JPS error than those receiving the graft more than 1 year after injury at 3 months. No complications were associated with either ACLR method.

CONCLUSION

ACLR with a hamstring tendon autograft or LARS artificial graft is similarly safe and effective for recovering knee proprioception.

Environmental Risk Factors for Osteoarthritis: The Impact on Individuals with Knee Joint Injury

Osteoarthritis is a debilitating chronic condition involving joint degeneration, impacting over 300 million people worldwide. This places a high social and economic burden on society. The knee is the most common joint impacted by osteoarthritis. A common cause of osteoarthritis is traumatic joint injury, specifically injury to the anterior cruciate ligament. The purpose of this review is to detail the non-modifiable and modifiable risk factors for osteoarthritis with particular focus on individuals after anterior cruciate ligament injury. After reading this, health care providers will better comprehend the wide variety of factors linked to osteoarthritis.

[Attentional focus instructions for therapeutic exercise in people with musculoskeletal disorders. A scoping review]

Attentional focus instructions are verbal strategies that could maximize the effects of exercise. The objective of this review was to explore and synthesize the available evidence on the incorporation of attentional focus instruction in the exercise of people with musculoskeletal disorders. A search of 11 databases was carried out until October 2020. Of 4,227 studies identified in the searches, 15 were included. The studies showed deficiencies in the conceptualization and definition of attentional focus instructions. The available evidence indicates that external focus is effective in improving motor learning and function. However, methodological limitations, clinical heterogeneity, the small number of articles included, and new experimental studies challenge the conclusions of the systematic reviews available to date. Attentional focus instructions in musculoskeletal disorders is an emerging field and requires further research. This review is a guide for future studies.

Acute and Long-Term Effects of Attentional Focus Strategies on Muscular Strength: A Meta-Analysis

This review aimed to perform a meta-analysis examining the following: (a) acute effects of adopting an internal focus vs. external focus of attention on muscular strength; and (b) long-term effects of adopting an internal focus vs. external focus of attention during resistance training on gains in muscular strength. We searched through five databases to find eligible studies. Random-effects meta-analyses of standardized mean differences were conducted to analyze the data. Ten studies were included. In the meta-analysis for the acute effects, there was a significant positive effect of external focus on muscular strength (standardized mean difference: 0.34; 95% confidence interval: 0.22, 0.46). In the meta-analysis for the long-term effects, there was no significant difference between training with an internal focus and external focus on muscular strength gains (standardized mean difference: 0.32; 95% confidence interval: –0.08, 0.73). In the subgroup analysis for lower-body exercises, we found a significant positive effect of training with an external focus on muscular strength gains (standardized mean difference: 0.47; 95% confidence interval: 0.07, 0.87). In summary, our findings indicate an acute increase in muscular strength when utilizing an external focus of attention. When applied over the long-term, using an external focus of attention may also enhance resistance training-induced gains in lower-body muscular strength.