CAN A WEARABLE NEUROMUSCUAR DEVICE REPLACE NEUROMUSCULAR TRAINING PROGRAMS?

Background: Scientific studies have shown female soccer athletes to be 3 times more likely to injure their anterior cruciate ligament (ACL) than their male counterparts and the majority of these injuries are from a non-contact mechanism. The biomechanical factors of this phenomenon have been extensively studied in a laboratory-based setting, but there has been little progress in reducing the incidence of ACL injury in young female athletes. It is plausible, therefore, to suggest that the biomechanical improvements noted in a laboratory-based setting do not directly translate to a field-based setting. Preventive neuromuscular training programs are typically field-based and have been shown to be an effective intervention for reducing ACL injury risk by improving dynamic, frontal-plane knee stability. However, these programs are time consuming and prone to compliance and implementation issues. For these reasons, researchers have attempted to identify the minimum viable training program or wearable device that can be studied in the field using video cameras to determine their influence on movement-related risk factors for ACL injury. Purpose: The aim of this study was to evaluate the effectiveness of a wearable neuromuscular device (WND) with or without the addition of a field-based, preventive neuromuscular training program on jump-landing risk assessment in young female soccer athletes. Methods: Thirty-nine female soccer players (161.0 +/- 6.6 cm; 49.4 kg +/- 5.9; 13.3 +/- 0.5 y) from two different teams in a local soccer club volunteered to participate in this study. Team 1 (n = 25) performed a 6-week, field-based NMT program while wearing a WND. The NMT was instructed by a trained exercise specialist. The NMT program was divided into three, two-week blocks of progressively increasing levels of exercise complexity and intensity focused on improving the strength and activation behavior of the trunk, hip and thigh muscles. Field-based movement testing was performed in the first week before training began (pre-test) and in the seventh week upon completion of the NMT program (post-test). During testing video cameras recorded a jump-landing task in the frontal and sagittal planes. The Landing Error Scoring System (LESS) and a novel version of the LESS (LESS-RMC) was used to asses movement quality related to ACL injury risk. Team 2 (n=14) wore the WND for an equal amount of athletic exposures over 7 weeks but did not perform the NMT program. Four different raters were recruited to visually score all jump landing trials using the two different rating protocols during the pre-test and post-test. For each visual assessment (LESS & LESS-RMC) a repeated measures ANOVA was conducted to explore within group (test) and between group (team) differences. Results: Repeated measure ANOVA results for the LESS score scale indicated a significant within factor difference in pretest and post test scores F(7.398, 27.533) = 8.598, P < 0.05. Pretest scores for team 1 (6.18 +/- 1.68) and team 2 (6.95 +/- 0.94) both saw a significant reduction in ACL risk scores to 5.44 +/- 1.70 and 6.31 +/- 1.75, respectively. ANOVA results for the LESS-RMC scale also indicated a significant within factor difference in pretest and posttests F(6.756, 35.624) = 6.069, p < 0.05. Pretest scores for Team 1 (6.02 +/- 1.99) and Team 2 (6.49 +/- 1.33) both saw a significant reduction in ACL risk scores to 5.10 +/- 1.77 and 6.09 +/- 1.50, respectively. ANOVA results revealed no significant differences between team scores for the LESS (F(0.031,27.533) = 0.036, p > 0.05) or LESS-RMC (F(1.053,35.624) = .946, p > 0.05) scales. Conclusion: The results reveal that the NMT program utilized in this study had no statistically significant additive effect on the visual risk assessment scores for Team 1 compared to Team 2, who had no NMT intervention and only wore the WND. Collectively, these results suggest that simply wearing a WND during 6 weeks of practice may be a less evasive and cheaper alternative to a NMT program.

Download Full-text

Optimizing Whole-Body Kinematics During Single-Leg Jump Landing to Reduce Peak Abduction/Adduction and Internal Rotation Knee Moments: Implications for Anterior Cruciate Ligament Injury Risk

Journal of Applied Biomechanics ◽

10.1123/jab.2020-0407 ◽

2021 ◽

pp. 1-8

Author(s):

Dhruv Gupta ◽

Jeffrey A. Reinbolt ◽

Cyril J. Donnelly

Keyword(s):

Internal Rotation ◽

Injury Risk ◽

Cruciate Ligament ◽

Acl Injury ◽

Whole Body ◽

Jump Landing ◽

Peak Knee ◽

Knee Abduction ◽

Acl Injury Risk ◽

Anterior Cruciate

Knee abduction/adduction moment and knee internal rotation moment are known surrogate measures of anterior cruciate ligament (ACL) load during tasks like sidestepping and single-leg landing. Previous experimental literature has shown that a variety of kinematic strategies are associated or correlated with ACL injury risk; however, the optimal kinematic strategies needed to reduce peak knee moments and ACL injury are not well understood. To understand the complex, multifaceted kinematic factors underpinning ACL injury risk and to optimize kinematics to prevent the ACL injury, a musculoskeletal modeling and simulation experimental design was used. A 14-segment, 37-degree-of-freedom, dynamically consistent skeletal model driven by force/torque actuators was used to simulate whole-body single-leg jump landing kinematics. Using the residual reduction algorithm in OpenSim, whole-body kinematics were optimized to reduce the peak knee abduction/adduction and internal/external rotation moments simultaneously. This optimization was repeated across 30 single-leg jump landing trials from 10 participants. The general optimal kinematic strategy was to bring the knee to a more neutral alignment in the transverse plane and frontal plane (featured by reduced hip adduction angle and increased knee adduction angle). This optimized whole-body kinematic strategy significantly reduced the peak knee abduction/adduction and internal rotation moments, transferring most of the knee load to the hip.

Download Full-text

REAL-TIME BIOFEEDBACK INTEGRATED INTO NEUROMUSCULAR TRAINING INCREASES BRAIN FUNCTIONAL CONNECTIVITY AND REDUCES HIGH-RISK KNEE BIOMECHANICS

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967119s00022 ◽

2019 ◽

Vol 7 (3_suppl) ◽

pp. 2325967119S0002 ◽

Cited By ~ 1

Author(s):

Jed A. Diekfuss ◽

Dustin R. Grooms ◽

Kim Barber Foss ◽

Scott Bonnette ◽

Chris Dicesare ◽

...

Keyword(s):

Functional Connectivity ◽

Real Time ◽

Injury Risk ◽

Pearson Correlation ◽

Correlation Coefficients ◽

Acl Injury ◽

Neuromuscular Training ◽

Acl Injury Risk ◽

Left Thalamus ◽

The Right

Background: Anterior cruciate ligament (ACL) injury is associated with alterations in the central nervous system and resultant sensorimotor control (Courtney et al., 2005; Grooms et al., 2017). Our prospective data indicates that altered knee-motor functional brain connectivity is associated with increased risk for ACL injury (Diekfuss et al., revisions invited), revealing novel neural targets for neuromuscular training interventions. Specifically, interventions that integrate concomitant sensorimotor feedback with injury prevention techniques have the potential to enhance brain functional connectivity to optimize ACL injury risk reduction strategies. To deliver concomitant sensorimotor feedback, we have developed an augmented neuromuscular training (aNMT) system that utilizes interactive, real-time biofeedback to simultaneously target multiple biomechanical variables associated with ACL injury risk (Bonnette et al., in press; Figure 1A). aNMT calculates and maps key biomechanical parameters to an interactive graphical shape that responds in real time as a function of participants’ movements. Participants are instructed to perform exercises to achieve a goal shape, which equates to producing biomechanical parameters associated with ACL injury risk reduction, while deviations toward injury risk factors result in specific shape distortions. We hypothesized that aNMT would significantly improve biomechanics associated with ACL injury risk and also increase knee-motor functional connectivity. We further predicted that the identified connectivity changes would be associated with the hypothesized changes in biomechanics. Methods: Over six weeks of training, participants (n = 25) performed a series of aNMT-based progressive exercises (e.g., squat, overhead squat, squat jump, tuck jump, single-leg Romanian dead lift, pistol squat) and completed a drop vertical jump (DVJ) task while fully instrumented for 3D motion analysis pre- and post-training. Peak knee abduction moment (pKAM; bilateral average) from the DVJ was used as the biomechanical outcome variable. Resting-state functional magnetic resonance imaging (fMRI) scans were also collected pre- and post-training on a subset of the cohort (n = 17). Thirteen additional participants were recruited to serve as untrained controls and completed the DVJ and resting-state fMRI on two testing sessions separated by approximately 6 weeks. Twenty-five knee-motor regions of interest (ROIs) were created based on the areas of brain activation derived from previously published data (Grooms et al., 2015; Kapreli et al., 2007). Paired-samples t tests with a false discovery rate correction for multiple comparisons determined differences in functional connectivity among these 25 ROIs (post > pre). Fisher-transformed Pearson correlation coefficients between the average residual blood oxygen level dependent (BOLD) signal time series extracted from ROIs that demonstrated significant group level changes were associated with pKAM in DVJ task at pre- and post-training. The pre- and post-training Pearson correlation coefficients were subsequently compared using the cocor package (Diedenhofen & Musch, 2015) to determine if the two relationships were significantly different. Results: Results showed that pKAM in the aNMT group was significantly lower following aNMT (p < .05), while no significant changes were found between the two time points for controls (p > .05). Results also revealed significantly greater functional connectivity between the right supplementary motor area (SMA) and the left thalamus at post-training relative to pre-training for the aNMT group, t(16) = 3.37, p = .04 (Figure 1B). No significant differences between the two time points were observed for the controls (all p > .05). The association between pKAM and the right SMA and left thalamus at pre-training (r = -.22; Figure 1C) was significantly different compared to that at post-training (r = .26; Figure 1D), p < .05, with a positive relationship between pKAM and SMA and thalamus activation following aNMT biofeedback. No similar changes in pKAM and right SMA and left thalamus connectivity were observed for the untrained controls, p > .05. Conclusions/Significance: The right SMA is involved in the planning and coordination of movement, and the left thalamus is associated with neuromotor control. The increased functional connectivity between these regions, combined with the reduction in pKAM, which is associated with reduced risk of ACL injury, indicate a possible neural mechanism for improved motor adaption associated with aNMT biofeedback. These findings have distinct implications for ACL injury prevention strategies. Biofeedback tools such as aNMT can be designed to target specifically the neural drivers of aberrant movement biomechanics underlying increased ACL injury risk. [Figure: see text]

Download Full-text

The Effect of a Knee-ankle Restraint on ACL Injury Risk Reduction during Jump-landing

Procedia Engineering ◽

10.1016/j.proeng.2013.07.036 ◽

2013 ◽

Vol 60 ◽

pp. 300-306

Author(s):

Phillis S.P. Teng ◽

K.F. Leong ◽

P.Y. Huang ◽

J. McLaren

Keyword(s):

Risk Reduction ◽

Injury Risk ◽

Acl Injury ◽

Jump Landing ◽

Acl Injury Risk

Download Full-text

Ankle Flexibility and Jump Landing Mechanics: Implications for ACL Injury Risk

International Journal of Athletic Therapy & Training ◽

10.1123/ijatt.16.6.14 ◽

2011 ◽

Vol 16 (6) ◽

pp. 14-16 ◽

Cited By ~ 1

Author(s):

Matthew Hamilton ◽

James R. Velasquez

Keyword(s):

Injury Risk ◽

Acl Injury ◽

Jump Landing ◽

Landing Mechanics ◽

Acl Injury Risk ◽

Ankle Flexibility

Download Full-text

Stiff Landings Are Associated With Increased ACL Injury Risk in Young Female Basketball and Floorball Players: Response

The American Journal of Sports Medicine ◽

10.1177/0363546517692762 ◽

2017 ◽

Vol 45 (3) ◽

pp. NP5-NP6 ◽

Cited By ~ 2

Author(s):

Mari Leppänen ◽

Kati Pasanen ◽

Urho M. Kujala ◽

Tommi Vasankari ◽

Pekka Kannus ◽

...

Keyword(s):

Injury Risk ◽

Acl Injury ◽

Young Female ◽

Acl Injury Risk

Download Full-text

RELIABILITY OF A NEW LANDING ERROR SCORING SYSTEM: THE LESS-RMC

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967119s00096 ◽

2019 ◽

Vol 7 (3_suppl) ◽

pp. 2325967119S0009

Author(s):

Ryan S. Wexler ◽

Sean Higinbotham ◽

Danny Blake ◽

Carlie Harrison ◽

Justin Hollenbeck ◽

...

Keyword(s):

Clinical Assessment ◽

Scoring System ◽

Injury Risk ◽

Knee Injury ◽

Assessment Tool ◽

Acl Injury ◽

Knee Valgus ◽

Jump Landing ◽

Acl Injury Risk ◽

The Mean

BACKGROUND Several biomechanical deficits have been shown to increase non-contact knee injury risk of the anterior cruciate ligament (ACL). The Landing Error Scoring System (LESS) is a clinical assessment tool that has been successfully used to predict the individuals that are at a high risk for injury and evaluate changes in landing technique after participation in a neuromuscular preventive training program. The LESS-RT is a shortened version of the LESS and is a method to score landing technique without the use of video. The current study proposes a new tool for the evaluation of landing technique and ACL injury risk that blends the LESS and LESS-RT protocols but emphasizes the movement features that contribute to high knee valgus moments including movement asymmetry. The LESS-RMC (Rocky Mountain Consortium) consists of evaluating 11 comprehensive landing errors that are related to ACL injury risk. Consolidating questions pertaining to the opposite ends of joint motion such as “toe in” and “toe out” into “maximum foot rotation position” and adding a global asymmetry score were performed to reduce the time demands for evaluation yet capture the salient factors of the LESS; whereas the penalty for knee valgus severity was pulled from the LESS-RT but implemented for both knees in the new LESS-RMC to ultimately stratify knee injury risk during the jump landing task. The purpose of this study was to determine the reliability of the new LESS-RMC assessment tool. METHODS Thirty-seven, elite female soccer athletes (13.2 +/- 0.4 y) performed three drop-jumps from a height of 30 cm. Front and side views of the landing were recorded with digital video cameras. Movement quality was rated by 4 researchers evaluating 17 components of the landing with the LESS and a modified, 11 component version of the LESS (LESS-RMC). The 4 raters were novel to the evaluation of both scoring systems. Each rater was trained how to score each test and was instructed to evaluate the landing trials from the first 10 participants. After a group video review and discussion, the raters repeated the scoring procedures for the same 10 participants 48 hours after the original review. After another 48 hours, the raters evaluated the landing trials for all 37 participants (111 trials). Inter-rater reliability of the LESS and LESS-RMC were determined using the ICC (3,1) equations and the output from a two-way ANOVA (SPSS, version 25). RESULTS The mean LESS score was 6.45 +/- 0.55 (rater 1, 6.42; rater 2, 7.15; rater 3, 5.79; rater 4, 6.45). The ICC agreement between raters of scoring the LESS was .389 whereas the ICC agreement for the mean of the four raters was .718. The ICC for scoring consistency was .382 and Cronbach’s a was .735. The mean LESS-RMC score was 6.19 +/- 0.74 (rater 1, 5.65; rater 2, 6.99; rater 3, 5.48; rater 4, 6.64). The ICC agreement of scoring the LESS-RMC was .585 whereas the ICC agreement for the mean of the four raters was .849. The ICC for scoring consistency was .574 and Cronbach’s a was .884. CONCLUSION On average, the raters scored the LESS and the LESS-RMC with moderate reliability across the group of athletes. The LESS-RMC was scored with greater reliability than the LESS for this group of relatively novice raters. This is likely due to the simplification of the overall protocol in terms of quantity of questions, the ability of a novel rater to understand scenarios which elicit specific scores and the clear separation of body segments (e.g. hip and trunk flexion). In conjunction with this, it was reported by the raters that LESS-RMC was less redundant and more effective at assessing crucial aspects of a jump landing pattern. Overall, LESS RMC was objectively and subjectively more reliable and easier to use than the LESS for the four raters involved in this study. It is concluded that the LESS-RMC is a quick, easy and reliable clinical assessment tool that may be used to stratify individuals who may be at risk for ACL injury.

Download Full-text

Stiff Landings Are Associated With Increased ACL Injury Risk in Young Female Basketball and Floorball Players

The American Journal of Sports Medicine ◽

10.1177/0363546516665810 ◽

2016 ◽

Vol 45 (2) ◽

pp. 386-393 ◽

Cited By ~ 95

Author(s):

Mari Leppänen ◽

Kati Pasanen ◽

Urho M. Kujala ◽

Tommi Vasankari ◽

Pekka Kannus ◽

...

Keyword(s):

Knee Flexion ◽

Injury Risk ◽

Acl Injury ◽

Young Female ◽

Flexion Angle ◽

Knee Flexion Angle ◽

Acl Injuries ◽

Increased Risk ◽

Peak Knee ◽

Acl Injury Risk

Background: Few prospective studies have investigated the biomechanical risk factors of anterior cruciate ligament (ACL) injury. Purpose: To investigate the relationship between biomechanical characteristics of vertical drop jump (VDJ) performance and the risk of ACL injury in young female basketball and floorball players. Study Design: Cohort study; Level of evidence, 3. Methods: At baseline, a total of 171 female basketball and floorball players (age range, 12-21 years) participated in a VDJ test using 3-dimensional motion analysis. The following biomechanical variables were analyzed: (1) knee valgus angle at initial contact (IC), (2) peak knee abduction moment, (3) knee flexion angle at IC, (4) peak knee flexion angle, (5) peak vertical ground-reaction force (vGRF), and (6) medial knee displacement. All new ACL injuries, as well as match and training exposure, were then recorded for 1 to 3 years. Cox regression models were used to calculate hazard ratios (HRs) and 95% CIs. Results: Fifteen new ACL injuries occurred during the study period (0.2 injuries/1000 player-hours). Of the 6 factors considered, lower peak knee flexion angle (HR for each 10° increase in knee flexion angle, 0.55; 95% CI, 0.34-0.88) and higher peak vGRF (HR for each 100-N increase in vGRF, 1.26; 95% CI, 1.09-1.45) were the only factors associated with increased risk of ACL injury. A receiver operating characteristic (ROC) curve analysis showed an area under the curve of 0.6 for peak knee flexion and 0.7 for vGRF, indicating a failed-to-fair combined sensitivity and specificity of the test. Conclusions: Stiff landings, with less knee flexion and greater vGRF, in a VDJ test were associated with increased risk of ACL injury among young female basketball and floorball players. However, although 2 factors (decreased peak knee flexion and increased vGRF) had significant associations with ACL injury risk, the ROC curve analyses revealed that these variables cannot be used for screening of athletes.

Download Full-text