Clinician-friendly lower extremity physical performance tests in athletes: a systematic review of measurement properties and correlation with injury. Part 2—the tests for the hip, thigh, foot and ankle including the star excursion balance test

Clinic- and laboratory-based measures of postural control in patellofemoral pain: A systematic review with meta-analysis and evidence gap map

BACKGROUND

Patellofemoral pain (PFP) is a prevalent musculoskeletal disorder associated with functional impairments. Although postural control is commonly assessed in people with PFP, there are inconsistent results regarding potential postural control deficits in this population.

RESEARCH QUESTION

This review aims to evaluate whether postural control is impaired in people with patellofemoral pain (PFP) and the effectiveness of interventions on postural control measures.

METHODS

We searched six databases from their inception to May 5, 2023. We included studies assessing clinic- or laboratory-based postural control measures in people with PFP compared to pain-free controls, and intervention studies with PFP populations. We assessed risk of bias using the Joanna Briggs Institute critical appraisal checklists and the Cochrane Risk of Bias 2 tool. We assessed the certainty of evidence using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. We used random-effects meta-analyses considering subgroups based on type of task, measure, and intervention.

RESULTS

Fifty-three studies were included. Very low certainty evidence indicated that people with PFP have shorter anterior (SMD = 0.53, 95 %CI:0.16,0.90), posteromedial (SMD = 0.54, 95 %CI:0.04,1.03) and posterolateral (SMD = 0.59, 95 %CI:0.11,1.07) reach distance, and worse composite score (SMD = 0.46, 95 %CI:0.22,0.70). Very low to moderate certainty evidence indicated that people with PFP have worse anterior-posterior and overall stability indexes during single-leg stance (SMD = -0.71, 95 %CI:-1.29,-0.14; SMD = -0.63, 95 %CI:-0.94,-0.32) and overall stability index during double-leg stance (SMD = -0.39, 95 %CI:-0.78,-0.00), but no differences in center of pressure area during stair ascent (SMD = 0.32, 95 %CI:-2.72, 3.36). Low certainty evidence indicated that kinesio taping improved anterior reach distance (SMD = -0.49, 95 %CI:-0.89,-0.09), while no significant differences were observed between pre- and post-intervention outcomes for conventional rehabilitation and rigid taping.

SIGNIFICANCE

Clinicians should use clinic- (star excursion or Y-balance tests) and laboratory-based (stability indexes) measures to identify impairments of postural control in people with PFP. Low certainty of evidence suggests short-term improvement in postural control with kinesio taping.

Test-retest, intra- and inter-rater reliability of the reactive balance test in patients with chronic ankle instability

Introduction

The Reactive Balance Test (RBT) could be a valuable addition to research on chronic ankle instability (CAI) and clinical practice, but before it can be used in clinical practice it needs to be reliable. It has already been proven reliable in healthy recreational athletes, but not yet in patients with CAI who have shown persistent deficits in dynamic balance. The study aimed to determine the test-retest, intra-, and inter-rater reliability of the RBT in patients with CAI, and the test-retest and inter-rater reliability of the newly developed RBT score sheet.

Methods

We used a repeated-measures, single-group design to administer the RBT to CAI patients on three occasions, scored by multiple raters. We included 27 participants with CAI. The study used multiple reliability measures, including Pearson r, intra-class correlations (ICC), standard error of measurement (SEM), standard error of prediction (SEP), minimal detectable change (MDC), and Bland-Altman plots, to evaluate the reliability of the RBT's outcome measures (visuomotor response time and accuracy). It also assessed the test-retest and inter-rater reliability of the RBT score sheet using the same measures.

Results

The ICC measures for test-retest reliability were similar for accuracy (0.609) and VMRT (0.594). Intra-rater reliability had high correlations and ICCs for accuracy (r = 0.816, ICC = 0.815) and VMRT (r = 0.802, ICC = 0.800). Inter-rater reliability had a higher ICC for VMRT (0.868) than for accuracy (0.690).

Conclusion

Test-retest reliability was moderate, intra-rater reliability was good, and inter-rater reliability showed moderate reliability for accuracy and good reliability for VMRT. Additionally, the RBT shows robust SEM and mean difference measures. The score sheet method also demonstrated moderate test-retest reliability, while inter-rater reliability was good to excellent. This suggests that the RBT can be a valuable tool in assessing and monitoring balance in patients with CAI.

Measurement properties of upper extremity physical performance tests in athletes: a systematic review

BACKGROUND

Upper extremity Physical Performance Tests (PPTs) have been used in sports contexts to provide functional status of the athletes. However, whether these tests present appropriate measurement properties to be considered a valuable measurement is not clear.

OBJECTIVE

To systematically review the measurement properties of upper extremity PPTs in athletes.

METHODS

Databases (e.g., Medline, EMBASE, CINAHL, SPORTDiscus, CENTRAL) were searched in March 2021. Two reviewers independently rated the methodological quality using the 4-point Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) checklist. Quality of evidence was graded by measurement property for each test, considering the adequacy, the sample size, and the methodological quality of the studies.

RESULTS

Fifteen studies were included with a pooled sample of 684 athletes. The PPTs analyzed were Arm-Jump Board Test, Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST), Finger Hang Test, Medicine Ball Explosive Power Test, One-Arm Hop Test, Posterior Shoulder Endurance Test, Pull-Up Shoulder Endurance Test, Repetition to Failure Assessment, Seated Medicine Ball Throw Test (SMBT), Seated Single-Arm Shot-Put Test (SSPT), Shoulder Endurance Test, Two-Arm Bent Hang Test, Unilateral Seated Shot-Put Test, and Upper Limb Rotation Test. Evidence synthesis provided moderate and high-quality evidence for sufficient inter-session and intra-session reliability of the CKCUEST, respectively. There was moderate evidence for sufficient inter-session reliability of the SSPT and for insufficient validity of the SMBT.

CONCLUSION

The CKCUEST and the SSPT are sufficiently reliable in athletes. More studies are needed to investigate other psychometric properties for these tests and other upper extremity PPTs.

Anterior component of Y-Balance test is correlated to ankle dorsiflexion range of motion in futsal players: A cross-sectional study

BACKGROUND AND PURPOSE

Restricted dorsiflexion range of motion (DFROM) could impact dynamic balance in sports. This study aimed to investigate the relationship between dorsiflexion range of motion and the Y-Balance Test (YBT) in elite futsal players.

METHODS

Sixty-one asymptomatic male futsal players (mean age 26.57 (5.64) years, a mean body mass index of 25.40 (2.69) kg/m2 ) were included. DFROM was measured by the weight-bearing lunge test (WBLT). DFROM data were obtained using smartphone-based motion capture. The Pearson correlation coefficient verified the correlation between the variables.

RESULTS

Dominant and nondominant leg ankle DFROM was significantly correlated with the anterior component of YBT (r = 0.27 and 0.51, respectively). The posteromedial component and the composite score of the YBT were also significantly correlated with nondominant leg ankle DFROM (r = 0.31 and 0.34, respectively)]. The other measures were not statistically significant. DFROM explained between 7% and 24% of the variation of the distances reached in the YBT.

CONCLUSION

Dorsiflexion range of motion measured by weight bearing lunge test is positively correlated with dynamic balance in futsal players.

Lower Extremity Muscle Activation during the Star Excursion Balance Test in Patients with Chronic Ankle Instability and Copers

Background and Objectives: The aim of this study was to assess the impact of ankle muscles on performance of the Star Excursion Balance Test (SEBT) among individuals with stable ankles, a history of ankle sprain, and chronic ankle instability (CAI). Materials and Methods: Sixty subjects (twenty per group) performed the SEBT in each of the anterior (A), posteromedial (PM), and posterolateral (PL) directions. Normalized maximum reach distance (NMRD) and normalized mean amplitude of the tibialis anterior (NMA_TA), fibularis longus (NMA_FL), and medial gastrocnemius (NMA_MG) were measured during performance of the SEBT. Results: Copers have greater NMRD than subjects with stable ankles and those with CAI, and subjects with stable ankles also have greater NMRD than those with CAI in only the PL direction. Subjects with stable ankles and those with CAI showed greater NMA_TA than copers. The A direction showed greater NMA_TA than the PM and PL directions. Copers showed greater NMA_FL than subjects with stable ankles. Subjects with CAI showed greater NMA_MG than copers and subjects with stable ankles. The A and PL directions showed greater NMA_MG than the PM direction. Conclusions: Overall, copers and/or subjects with CAI demonstrated altered neuromuscular function by compensating for their ankle muscles when compared to subjects with stable ankles due to a history of ankle sprain.

Physical Performance and Mobility Tests Using Telehealth: A Feasibility Study With Athletes

CONTEXT

Physical performance tests (PPTs) and mobility tests have been widely used in sports rehabilitation. However, the feasibility of PPTs and mobility tests via telehealth is unknown.

OBJECTIVES

To verify the feasibility of PPTs and mobility tests to assess athletes via telehealth.

DESIGN

This is a feasibility study.

PARTICIPANTS

Athletes enrolled in a sports team or club for at least 2 years and with previous enrollment in a competitive league were recruited through advertisements on social media. The athletes included in this study (mean age = 25.9 y, from different sports) performed a battery of PPTs and mobility tests for the lower-extremity or upper-extremity and trunk, according to their sport modality.

MAIN OUTCOME MEASURE

The feasibility was assessed with recruitment, success, and dropout rates. In addition, athletes' perceptions of easiness, satisfaction, and safety during the lower-extremity or upper-extremity and trunk PPTs and mobility tests were assessed.

RESULTS

Seventy-three athletes were included, between January and April 2021: 41 were allocated to the lower-extremity and 32 to the upper-extremity and trunk PPTs and mobility test, according to their sports modality. The overall dropout rate was 20.55%; >89% of the athletes agreed that the PPTs and mobility tests via telehealth were easy to perform, >78% were satisfied, and >75% felt safe during the assessments.

CONCLUSION

This study indicated that these 2 batteries of performance and mobility tests via telehealth are feasible to assess the lower and upper-extremities, and the trunk of athletes, considering the adherence, athletes' perception of easiness, satisfaction, and safety.

Lower Extremity Physical Performance Tests for the Assessment of Athletes via Telehealth are Reliable

CONTEXT

Lower extremity physical performance tests (PPTs) have been widely used in sports rehabilitation and are commonly performed in person. However, some situations may disrupt the in-person health care delivery, such as social distancing due to the pandemic, traveling, and living in remote locations. Those situations may require adjustments in planning and applying measurement tests, and telehealth has become an alternative. Nevertheless, the reliability of lower extremity PPT tests via telehealth is still unknown.

OBJECTIVES

To verify the test-retest reliability, SEM, and the minimum detectable change (MDC95) of PPTs via telehealth.

METHODS

Fifty asymptomatic athletes completed 2 assessment sessions 7 to 14 days apart. The assessment via telehealth consisted of warm-up exercises followed by the single-, triple-, and side-hop tests, and the long jump test, in random order. Intraclass correlation coefficient, SEM, and MDC95 were calculated for each PPT.

RESULTS

Single-hop test showed good to excellent reliability, with SEM and MDC95 ranging from 6.06 to 9.24 cm and 16.79 to 25.61 cm, respectively. The triple-hop test showed excellent reliability, with SEM and MDC95 ranging from 13.17 to 28.17 cm and 30.72 to 78.07 cm, respectively. Side-hop tests showed moderate reliability, with SEM and MDC95 ranging from 0.67 to 1.22 seconds and 2.00 to 3.39 seconds, respectively. The long jump test showed excellent reliability, with SEM and MDC95 ranging from 5.34 to 8.34 cm and 14.80 to 23.11 cm, respectively.

CONCLUSION

The test-retest reliability of those PPTs via telehealth was acceptable. The SEM and MDC were provided to assist clinicians in interpreting those PPTs.

INFLUENCE OF HIGH-INTENSITY TRAINING ON THE TAEKWONDO ATHLETES’ PERFORMANCE

ABSTRACT Introduction: Taekwondo athletes’ performance is affected by their level of physical fitness. High-level athletes must have good physical fitness to perform difficult techniques and complex sets of movements with high specificity. Objective: Verify the influence of high-intensity training on fitness levels for the selection and daily training of taekwondo athletes in colleges and universities. Methods: In this study, 47 high-level taekwondo athletes from the Capital Institute of Physical Education were considered and statistically analyzed employing literature, expert interview, tests, mathematical statistics, and logical analysis. The factors influencing physical fitness were determined. Results: Five first-level, nine second-level, and 15 third-level test indicators based on the combination of general fitness and specific fitness of athletes were determined. Fitness test analysis was performed before and after 12 weeks of daily high-intensity training demonstrating that the athletes’ physical quality showed an upward trend, especially in terms of strength, endurance, and flexibility. Still, speed and agility showed no statistical change. Conclusion: Fitness training of high-level taekwondo athletes should be combined with particular techniques, focusing on training the five qualities of strength, speed, endurance, agility, and flexibility. It is recommended to individually plan the training cycle and intensity of each training session, to carry out a targeted training plan, and to ensure a training plan with regularity. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Establishing Normative Dynamic Postural Control Values in Elite Female Handball Players

Background

Lower extremity injuries among young female handball players are very common. The modified Star Excursion Balance Test (mSEBT) is a valid clinical tool to assess dynamic postural control and identify athletes with higher risk of injury. However, its interpretation is difficult since performance on this test is highly sport dependent. No normative values on the mSEBT exist in handball.

Purpose

The aim of this investigation was to establish normative ranges of mSEBT performance in young, healthy female handball players to help practitioners when interpreting risk estimates.

Study design

Cross-Sectional Study.

Methods

Athletes from 14 elite teams were recruited during a national tournament and performed 3 trials in the anterior (ANT), posteromedial (PM), posterolateral (PL) directions of the mSEBT. Means, standard deviations and 95% confidence intervals (95%CI) of normalized reached distances were calculated for each direction and the composite score (COMP). Level of asymmetry between dominant and non-dominant limbs were calculated for each direction using Bland Altman analyses. Group differences were weighed against the established mSEBT minimum detectable differences (MDD) to compare scores between limbs and across different player positions.

Results

One-hundred and eighty-eight females (16.8±0.9 years) were tested. Mean reach distances were 65.2±5% (64.7-65.7), 110.0±6.2% (109.3-110.6), 107.1±6.2% (106.5-107.8) and 94.1±4.9% (93.6-94.6) for the ANT, PM, PL directions and COMP score respectively. Bias and limits of agreement for limb asymmetry were -0.23% (-5.85%, 5.38%) for ANT, -0.83% (-8.80%, 7.14%) for PM, 0.33% (-8.51%, 9.17%) for PL and -0.27% (-4.88%, 4.33%) for COMP score. No meaningful differences were observed between limbs or across player positions since the values did not exceed the MDD and all 95%CIs overlapped.

Conclusion

This study provides normative performance values for dynamic postural control as measured by the mSEBT among young, healthy, elite female handball players. Considering the high incidence of injury in this population, these values can be used for injury risk reduction and return to sport decisions. Further prospective studies are needed to established specific cut-off scores in this population.

Level of evidence

2c.

Disagreement in Pass Rates Between Strength and Performance Tests in Patients Recovering From Anterior Cruciate Ligament Reconstruction

BACKGROUND

Performance on strength and functional tests is often used to guide postoperative rehabilitation progress and return to activity decisions after anterior cruciate ligament reconstruction (ACLR). Clinicians may have difficulty in determining which criteria to follow if there is disagreement in performance outcomes among the tests.

PURPOSE/HYPOTHESIS

The purpose of this study was to compare pass rates between strength tests and single-leg hop (SLHOP) tests among men and women and between patients with lower and higher preinjury activity levels recovering from ACLR. We hypothesized that pass rates would be nonuniformly distributed among test types, sex, and activity level and that more participants would pass hop tests than strength tests.

DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A total of 299 participants (146 men; 153 women)-at a mean of 6.8 ± 1.4 months after primary, unilateral, and uncomplicated ACLR (mean age, 23 ± 9.7 years; mean height, 172 ± 10.5 cm; mean mass, 75.8 ± 18.4 kg)-completed testing. Quadri.tif strength was evaluated using peak torque during isokinetic knee extension at 90 deg/s and 180 deg/s. Jump distance during the SLHOP and triple hop tests was measured (in cm). Strength and hop test measures were evaluated based on the limb symmetry index ((LSI) = (ACLR / contralateral side) × 100). We operationally defined "pass" as >90% on the LSI.

RESULTS

Pass rates were nonuniformly distributed between isokinetic knee extension at 90 deg/s and the SLHOP test (χ² = 18.64; P < .001). Disagreements between isokinetic testing at 90 deg/s and the SLHOP test occurred in 36.5% (109/299) of the participants. Among those who failed strength testing and passed hop testing, a greater portion reported higher activity levels before their injury (χ² = 6.90; P = .01); however, there was no difference in pass rates between men and women. Similar patterns of disagreement were observed between all strength test and hop test outcomes.

CONCLUSION

ACLR patients with higher activity levels may be more likely to pass hop testing despite failing quadri.tif strength testing. This may be an indicator of movement compensations to achieve jump symmetry in the presence of quadri.tif weakness.

Which Functional Tests and Self-Reported Questionnaires Can Help Clinicians Make Valid Return to Sport Decisions in Patients With Chronic Ankle Instability? A Narrative Review and Expert Opinion

Lateral ankle sprain is the most common injury in sports, with up to 40% of patients developing chronic ankle instability (CAI). One possible cause underlying this high rate of recurrence or feeling of giving way may be a premature return to sport (RTS). Indeed, except for time-based parameters, there are no specific criteria to guide clinicians in their RTS decisions in patients with CAI. A recent international consensus highlighted the relevance and importance of including patient-reported ankle function questionnaires combined with functional tests targeting ankle impairments in this population. Thus, the aim of this narrative review and expert opinion was to identify the most relevant functional performance tests and self-reported questionnaires to help clinicians in their RTS decision-making process following recurrent ankle sprains or surgical ankle stabilization. The PubMed (MEDLINE), PEDro, Cochrane Library and ScienceDirect databases were searched to identify published articles. Results showed that the single leg stance test on firm surfaces, the modified version of the star excursion balance test, the side hop test and the figure-of-8 test appeared to be the most relevant functional performance tests to target ankle impairments in patients with CAI. A combination of the Foot and Ankle Ability Measure (FAAM) and the Ankle Ligament Reconstruction-Return to Sport after Injury (ALR-RSI) questionnaires were the most relevant self-reported questionnaires to assess patient function in the context of CAI. Although these functional tests and questionnaires provide a solid foundation for clinicians to validate their RTS decisions in patient with CAI, objective scientific criteria with cut-off scores are still lacking. In addition to the proposed test cluster, an analysis of the context, in particular characteristics related to sports (e.g., fatigue, cognitive constraints), to obtain more information about the patient's risk of recurrent injury could be of added value when making a RTS decision in patients with CAI. In order to evaluate the strength of evertors under ecological conditions, it would also be interesting to assess the ability to control weight-bearing ankle inversion in a unipodal stance. Further studies are needed to assess the relevance of this proposed test cluster in RTS decision-making following lateral ankle sprain injury and CAI.

Evaluation and Validation of the Dutch European Foot and Ankle Society (EFAS) Score

The European Foot and Ankle Society (EFAS) score is a recently developed foot and ankle patient-reported outcome measure. It has been developed and partly validated in seven languages. This study's aim was to investigate the measurement properties of the Dutch version of the EFAS score. Subscales of the Dutch EFAS score were evaluated in 547 patients with a variety of foot and ankle diagnoses. Floor and ceiling effect, reliability, and construct validity were assessed. The internal consistency of the EFAS score was acceptable (Cronbach's alpha 0.79-0.94). Repeatability was considered poor, with intraclass correlation coefficients between 0.32 and 0.39. Construct validity was inadequate with confirmation of 67% of the hypothesized correlations. In conclusion, the Dutch version of the EFAS score does not have adequate measurement properties for use in patient with patients with varying foot and ankle problems.

A Framework for Clinicians to Improve the Decision-Making Process in Return to Sport

Return-to-sport (RTS) decisions are critical to clinical sports medicine and are often characterised by uncertainties, such as re-injury risk, time pressure induced by competition schedule and social stress from coaches, families and supporters. RTS decisions have implications not only for the health and performance of an athlete, but also the sports organisation. RTS decision-making is a complex process, which relies on evaluating multiple biopsychosocial factors, and is influenced by contextual factors. In this narrative review, we outline how RTS decision-making of clinicians could be evaluated from a decision analysis perspective. To begin with, the RTS decision could be explained as a sequence of steps, with a decision basis as the core component. We first elucidate the methodological considerations in gathering information from RTS tests. Second, we identify how decision-making frameworks have evolved and adapt decision-making theories to the RTS context. Third, we discuss the preferences and perspectives of the athlete, performance coach and manager. We conclude by proposing a framework for clinicians to improve the quality of RTS decisions and make recommendations for daily practice and research.

Post-Operative Results of ACL Reconstruction Techniques on Single-Leg Hop Tests in Athletes: Hamstring Autograft vs. Hamstring Grafts Fixed Using Adjustable Cortical Suspension in Both the Femur and Tibia

Background and Objectives: Anterior cruciate ligament (ACL) tears are common injuries in the athletic population, and accordingly, ACL reconstruction (ACLR) is among the most common orthopedic surgical procedures performed in sports medicine. This study aims to compare the semitendinosus/gracilis (ST/G) and ACL hamstring grafts fixed using adjustable cortical suspension in both the femur and tibia (MAI) ACLR techniques. We aimed to compare the results of single-leg hop tests (SLHT) applied in different directions and limb symmetry indices (LSI) in athletes with a 6-month post-operative ACLR history. Materials and Methods: A retrospective cohort of 39 athletes from various sports branches who underwent MAI (n = 16) and ST/G (n = 23) ACLR techniques by the same surgeon were evaluated. The knee strength of the participants on the operated and non-operated sides was evaluated with five different SLHTs. The SLHT included the single hop for distance (SH), triple hop for distance (TH), crossover triple hop for distance (CH), medial side triple hop for distance (MSTH), and medial rotation (90°) hop for distance (MRH). Results: There was a significant improvement in the mean Lysholm, Tegner, and IKDC scores in the post-operative leg for both techniques (p < 0.05) compared to the pre-operative levels. When there was a difference between the SH of the operative and the non-operative legs in the ST/G technique (p < 0.05), there was no significant difference in the other hop distance for both ST/G and MAI (p > 0.05). There was no difference between the techniques regarding the LSI scores. Conclusions: The fact that our research revealed similar LSI rates of the SLHTs applied in different directions in the ST/G and MAI techniques assumes that the MAI technique can be an ACLR technique which can be functionally used in athletes.

Foot arch height, toe flexor strength, and dynamic balance ability in collegiate female dancers and non-dancers

[Purpose] To characterize the foot arch height, toe flexor strength, and dynamic balance ability of collegiate female dancers and age-matched non-dancers. [Participants and Methods] This study included 20 healthy college-aged female dancers (21.6 ± 0.8 years) and 20 age-matched females (19.7 ± 1.0 years) with no previous experience in sports as non-dancers. Foot arch height was determined by measuring the height of the navicular tuberosity in the standing position using a ruler. Toe flexor strength was measured while seated on a chair using a toe grip dynamometer. Dynamic balance ability was evaluated based on the reach distance measured using a professional Y-balance test kit. [Results] The collegiate dancers had higher foot arches, greater toe flexor strength, and longer Y-balance test reach distance than the non-dancers. [Conclusion] The foot arch height, toe flexor strength, and dynamic balance ability of collegiate female dancers were adapted through years of training and were superior to those of non-dancers.

Association Between Preseason Fitness Level and Risk of Injury or Illness in Male Elite Ice Hockey Players: A Prospective Cohort Study

Background:

Little is known about the association between physical fitness and the risk of injury or illness in ice hockey. The least-fit players may be more prone to injury and illness.

Purpose:

To examine the association between preseason fitness level and injury or illness risk among elite ice hockey players during the regular season.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

A total of 133 male ice hockey players in the GET League (the premier professional league in Norway) completed 8 different exercises (40-m sprint, countermovement jump, 3000-m run, squat, bench press, chin-ups, brutal bench, and box jump) at the annual 1-day preseason testing combine. During the 2017-2018 competitive season, the players reported all health problems (acute injuries, overuse injuries, and illnesses) weekly (31 weeks) using the Oslo Sports Trauma Research Center Questionnaire on Health Problems.

Results:

Overall, the players reported 191 acute injuries, 82 overuse injuries, and 132 illnesses. The least-fit tercile of players did not report more health problems (mean, 3.0; 95% CI, 2.2-3.8) compared with the most-fit (mean, 3.4; 95% CI, 2.6-4.2) or the medium-fit (mean, 2.7; 95% CI, 1.9-3.5) players. The most-fit players reported more substantial health problems (mean, 2.0; 95% CI, 1.6-2.5) compared with the medium-fit (mean, 1.3; 95% CI, 0.8 -1.8) and least-fit (mean, 1.8; 95% CI, 1.3-2.3) (P = .02) players. There was no association between low physical fitness and number of health problems when comparing the least-fit tercile of the players with the rest of the cohort (P > .05); however, there was an association between low physical fitness and greater severity of all health problems when comparing the least-fit tercile of players to the rest of the cohort after adjusting for time on ice per game, playing position, and age (P = .02).

Conclusion:

Low physical fitness was not associated with increased rate of injury or illness but was associated with greater severity of all health problems after adjusting for time on ice per game, playing position, and age.

Measurement Properties of Clinically Accessible Movement Assessment Tools for Analyzing Single-Leg Squats and Step-Downs: A Systematic Review

CONTEXT

Poor lower-extremity biomechanics are predictive of increased risk of injury. Clinicians analyze the single-leg squat (SLS) and step-down (SD) with rubrics and 2D assessments to identify these poor lower-extremity biomechanics. However, evidence on measurement properties of movement assessment tools is not strongly outlined. Measurement properties must be established before movement assessment tools are recommended for clinical use.

OBJECTIVE

The purpose of this study was to systematically review the evidence on measurement properties of rubrics and 2D assessments used to analyze an SLS and SD.

EVIDENCE ACQUISITION

The search strategy was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The search was performed in PubMed, SPORTDiscus, and Web of Science databases. The COnsensus-based Standards for the selection of health Measurement INstruments multiphase procedure was used to extract relevant data, evaluate methodological quality of each study, score the results of each movement assessment, and synthesize the evidence.

EVIDENCE SYNTHESIS

A total of 44 studies were included after applying eligibility criteria. Reliability and construct validity of knee frontal plane projection angle was acceptable, but criterion validity was unacceptable. Reliability of the Chmielewski rubric was unacceptable. Content validity of the knee-medial-foot and pelvic drop rubrics was acceptable. The remaining rubrics and 2D measurements had inconclusive or conflicting results regarding reliability and validity.

CONCLUSIONS

Knee frontal plane projection angle is reliable for analyzing the SLS and SD; however, it does not serve as a substitute for 3D motion analysis. The Chmielewski rubric is not recommended for assessing the SLS or SD as it may be unreliable. Most movement assessment tools yield indeterminate results. Within the literature, standardized names, procedures, and reporting of movement assessment tool reliability and validity are inconsistent.

Measurement Properties of Clinically Accessible Movement Assessment Tools for Analyzing Jump Landings: A Systematic Review

CONTEXT

Lower-extremity musculoskeletal injury is commonly associated with poor movement patterns at the trunk, hip, and knee. Efforts have been focused on identifying poor lower-extremity movement using clinically friendly movement assessments, such as rubrics and 2D measures. Assessments used clinically or for research should have acceptable measurement properties, such as reliability and validity. However, the literature on reliability and validity of movement assessments to analyze jump landings has not been summarized.

OBJECTIVE

To systematically review measurement properties of rubrics and 2D measurements that aim to classify movement quality during jump landings.

EVIDENCE ACQUISITION

The search strategy was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The search was performed in PubMed, SPORTDiscus, and Web of Science databases. The COnsensus-based Standards for the selection of health Measurement INstruments multiphase procedure was used to extract relevant data, evaluate methodological quality of each study, score the results of each movement assessment, and synthesize the evidence.

EVIDENCE SYNTHESIS

Twenty-two studies were included after applying eligibility criteria. Reliability and construct validity of the landing error scoring system were acceptable. Criterion validity of 2D knee flexion angle and medial knee displacement is acceptable. Reliability of 2D knee ankle separation ratio and knee frontal plane projection angle are acceptable.

CONCLUSION

The landing error scoring system is a valid way to determine poor movement quality and injury risk. Measures of 2D knee flexion angle and medial knee displacement are valid alternatives for 3D knee flexion angle and knee abduction moment, respectively. Knee ankle separation ratio and knee frontal plane projection angle are reliable but lack validity justifying their clinical use.

Identification of Neuromuscular Performance Parameters as Risk Factors of Non-contact Injuries in Male Elite Youth Soccer Players: A Preliminary Study on 62 Players With 25 Non-contact Injuries

Introduction: Elite youth soccer players suffer increasing numbers of injuries owing to constantly increasing physical demands. Deficits in neuromuscular performance may increase the risk of injury. Injury risk factors need to be identified and practical cut-off scores defined. Therefore, the purpose of the study was to assess neuromuscular performance parameters within a laboratory-based injury risk screening, to investigate their association with the risk of non-contact lower extremity injuries in elite youth soccer players, and to provide practice-relevant cut-off scores.

Methods: Sixty-two elite youth soccer players (age: 17.2 ± 1.1 years) performed unilateral postural control exercises in different conditions, isokinetic tests of concentric and eccentric knee extension and knee flexion (60°/s), isometric tests of hip adduction and abduction, and isometric tests of trunk flexion, extension, lateral flexion and transversal rotation during the preseason period. Non-contact lower extremities injuries were documented throughout 10 months. Risk profiling was assessed using a multivariate approach utilizing a Decision Tree model [Classification and Regression Tree (CART) method].

Results: Twenty-five non-contact injuries were registered. The Decision Tree model selected the COP sway, the peak torque for knee flexion concentric, the functional knee ratio and the path of the platform in that hierarchical order as important neuromuscular performance parameters to discriminate between injured and non-injured players. The classification showed a sensitivity of 0.73 and a specificity of 0.91. The relative risk was calculated at 4.2, meaning that the risk of suffering an injury is four times greater for a player, who has been classified as injured by the Decision Tree model.

Conclusion: Measuring static postural control, postural control under unstable condition and the strength of the thigh seem to enable a good indication of injury risk in elite youth soccer players. However, this finding has to be taken with caution due to a small number of injury cases. Nonetheless, these preliminary results may have practical implications for future directions in injury risk screening and in planning and developing customized training programs to counteract intrinsic injury risk factors in elite youth soccer players.

The Star Excursion Balance Test: An Update Review and Practical Guidelines

The Star Excursion Balance Test (SEBT) is a reliable, responsive, and clinically relevant functional assessment of lower limbs’ dynamic postural control. However, great disparity exists regarding its methodology and the reported outcomes. Large and specific databases from various population (sport, age, and gender) are needed to help clinicians when interpreting SEBT performances in daily practice. Several contributors to SEBT performances in each direction were recently highlighted. The purpose of this clinical commentary is to (a) provide an updated review of the design, implementation, and interpretation of the SEBT and (b) propose guidelines to standardize SEBT procedures for better comparisons across studies.

Association between pre-participation characteristics and risk of injury amongst pre-professional dancers

STUDY DESIGN

Prospective Cohort Study.

BACKGROUND

Few investigations utilize evidence-informed pre-participation evaluation, inclusive injury definitions, and prospective surveillance to identify risk factors for dance-related injuries.

OBJECTIVE

To evaluate pre-participation characteristics that may be associated with greater odds of dance-related musculoskeletal complaints in pre-professional dancers.

METHODS

Full-time pre-professional ballet [n = 85, 77 females, median (range) age 15-years (11-19)] and contemporary [n = 60, 58 females, 19-years (17-30)] dancers underwent pre-participation evaluation: baseline questionnaire, coping skills, body mass index, bone mineral density, ankle range-of-motion, active standing turnout, lumbopelvic control, and balance tests. Self-reported complaints (any physical problem making dance participation difficult, irrespective of medical attention or time-loss) were captured weekly via online questionnaires for one academic year. Self-reported musculoskeletal complaints were recorded weekly (yes/no). Potential risk factors were identified a-priori through systematic review. Associations between potential risk factors and musculoskeletal complaints were examined with generalized linear mixed method regression models.

RESULTS

Response rate was 99%, with 81% of dancers reporting at least one musculoskeletal complaint. Of 1521 complaints (19% first-time, 81% ongoing), the ankle (22%), knee (21%), and foot (12%) accounted for the majority. Injury history [odds ratio (OR) 7.37 (95% CI 3.41, 15.91)] and previous week's dance hours [OR 1.02 (1.01, 1.03)] were associated with dance-related musculoskeletal complaints.

CONCLUSIONS

Prevalence of musculoskeletal complaints amongst pre-professional dancers is high and associated with injury history and training volume. Further understanding of the relationship between training load and injury is needed, with particular consideration of the dynamic and recursive nature of dance injury etiology.

LEVEL OF EVIDENCE

Therapy / Prevention, Aetiology / Harm, level 2b.

The Relationship between Preseason Common Screening Tests to Identify Inter-Limb Asymmetries in High-Level Senior and Professional Soccer Players

This study sought to examine inter-limb asymmetries in common screening tests performed during preseason and to analyze the relationship between the performance in the different tests. Nineteen high-level senior and professional soccer players (age: 23.2 ± 3.1 years; height: 181 ± 0.06 cm; body mass: 75.2 ± 4.8 kg) performed several common screening tests during preseason: Dorsiflexion lunge test (DLT); bent knee fall out test (BKFO); y-balance anterior test (YBT A); y-balance posterolateral test (YBT PL); Y-balance posteromedial test (YBT PM); Heel-rise test (HRT) and single leg hamstring bridge test (SLHBT). High levels of reliability (ICC > 0.88 and <0.94) were observed in all the studied variables. Inter-limb significant differences were observed in DLT and YBT PM test (p < 0.01) but YBT A, HRT and SLHBT presented trivial effect size (ES) (0.03; 0.07 and 0.13, respectively), contrary to DLT, BKFO and YBT PL, all with small ES (0.20; −0.23 and −0.22) and YBT PM, which revealed very large ES (2.91). Considering all data, high-level senior and professional soccer players present fairly good mean values of lower limb symmetry. Performance considering all tests was different, a fact associated with different biomechanical dynamics (e.g., YBT), nonetheless, the correlations between tests underline the relationship between these, which could represent important evidence to consider for injury prevention and performance enhancement programs.

The Non-injured Leg Can Be Used as a Reference for the Injured Leg in Single-legged Hop Tests

BACKGROUND

Single-legged hop tests are frequently used in substantiating return to sport decisions following lower extremity injury. Evidence for using the non-injured leg as a reference for the injured leg in the return to sport decision-making at the criterion-based point of return to sport following lower extremity injury is lacking.

PURPOSE

To compare absolute values in single-legged hop tests between the non-injured leg of athletes returning to high-impact sports after lower extremity injury and the matched leg of healthy athletes.

STUDY DESIGN

Cross-sectional study.

METHODS

One hundred and sixty-nine athletes returning to high-impact sports after lower extremity injury and 169 matched healthy athletes executed five single-legged hop tests. Differences between athletes returning to high-impact sports after lower extremity injury and matched healthy athletes on five single-legged hop tests were analyzed using paired t-tests.

RESULTS

There were no statistically significant differences between the non-injured leg of athletes returning to sport and the matched leg of healthy athletes. Effect sizes ranged from 0.05 to 0.14 indicating negligible effects.

CONCLUSION

Clinicians can use the non-injured leg as a reference for the injured leg in single-legged hop tests for deciding on return to high-impact sports after lower extremity injuries.

LEVEL OF EVIDENCE

3b.

Pre- and post-match hop test outcomes in soccer players returning to performance after lower extremity injury

BACKGROUND

Most soccer injuries concern the lower extremity with a higher injury rate during the second half of matches. In advising safe return to sport, hop tests are usually assessed at the point of return to sport under non-fatigued conditions. No studies exist investigating hop test outcomes before and after a match in soccer players returning to performance after lower extremity injury and non-injured teammates. The objective is to assess differences in hop test outcomes before and after a match in and between soccer players returning to performance after lower extremity injury and their non-injured teammates.

METHODS

A repeated-measures design was used to measure outcomes on five hop tests before and after a soccer match. For analyzing differences in hop tests before and after a match, paired sample t-tests were used. Independent t-tests were used to analyze differences between soccer players after injury and non-injured teammates. Effect sizes were calculated using Cohen's d.

RESULTS

Hop tests were completed by 61 amateur soccer players after injury and 121 non-injured teammates. Differences in hop tests before and after the match within both groups had negligible to small effect sizes (d=0.00-0.49), except for the figure of 8 and 30 seconds side hop in the injured leg of RTPf soccer players (d=0.56 and d=0.71 respectively). Differences between both groups were negligible to small (d=0.00-0.36).

CONCLUSIONS

Soccer players returning to performance after a lower extremity injury showed similar scores on hop tests than their non-injured teammates. More demanding sport-specific performance test and measurement of quality of movement are additionally recommended for safe return to sport decision-making.

The Impact of Dance-Specific Neuromuscular Conditioning and Injury Prevention Training on Motor Control, Stability, Balance, Function and Injury in Professional Ballet Dancers: A Mixed-Methods Quasi-Experimental Study

BACKGROUND

Professional ballet dancers suffer high injury rates and are less likely than other athletes to specifically train to improve muscular strength, coordination, agility, speed and motor control because of heavy training demands, aesthetic appearances and financial barriers.

HYPOTHESIS/PURPOSE

The purpose of this study was to examine the effects of a supplemental conditioning program on professional and pre-professional contemporary ballet dancers. The authors hypothesized that those participating in a training program would reduce injury rate by improving their motor control, stability, balance and physical function. The authors aimed to observe the feasibility and qualitative phenomena related to a conditioning program from the dancer's perspective.

STUDY DESIGN

A mixed-methods study; within subject quasi-experimental design and qualitative interviews.

METHODS

Six professional classical and contemporary ballet dancers completed the five-week conditioning and injury prevention training program. Non-parametric analysis of baseline, posttest and four-month follow-up physical performance measures, subjective outcomes, and qualitative follow-up interviews, were reported.

RESULTS

Significant post-test improvements included: The Dance Functional Outcome Survey (Z= -2.2, p= 0.04), composite Modified Star Excursion Balance Test (Z= -2.2, p= 0.03 bilaterally), Single Leg Hop for Distance (Z= -2.02, p= 0.04), and Upper Extremity Closed Kinetic Chain Test (Z=-2.03, p= 0.04). Significant changes from baseline to the four-month follow up remained for: (1) Dance Functional Outcome Survey (Z= -2.2, p= 0.03), (2) Single Leg Hop for Distance (Z= -2.2, p= 0.03), and (3) Modified Star Excursion Balance Test composite maximum reach for the left lower extremity (Z= -2.2, p= 0.03).

CONCLUSION

Completing a conditioning and prevention program for professional ballet dancers was related to improved function, balance, hop distance/stability and upper extremity stability. Dancers found the program beneficial, identified barriers to participation, and elucidated factors making the program feasible and successful. More research is necessary to determine the effect of such programs on injury incidence.

LEVEL OF EVIDENCE

3b.

Side-hops challenge knee control in the frontal and transversal plane more than hops for distance or height among ACL-reconstructed individuals

We compared knee landing mechanics with presumed relation to risk of anterior cruciate ligament (ACL) injury among three single-leg hop tests and between legs in individuals with unilateral ACL reconstruction. Thirty-four participants (>10 months' post-surgery, 23 females) performed the standardised rebound side hop (SRSH), maximal hop for distance (OLHD) and maximal vertical hop (OLVH). We calculated the following knee outcomes from motion capture and force plate data: finite helical axis inclination angles (approximates knee robustness), frontal and transversal plane angles at initial contact, peak angles of abduction and internal rotation during landing, and peak external moments of flexion, abduction and internal rotation during landing. Repeated-measures MANOVA analysis ('sex' as covariate) confirmed that SRSH induced greater angles and moments, particularly in the frontal plane, compared to OLHD and OLVH. There was between-leg asymmetry for peak knee flexion moment for males during OLHD and OLVH, and for females during SRSH. Our results advocate the SRSH over OLHD and OLVH for assessment of knee landing control to screen for movement patterns potentially related to ACL injury risk. However, clear differences in both knee kinematics and kinetics between OLHD and SRSH motivate the use of both tests to evaluate different aspects of landing control.

Does Mental Fatigue Negatively Affect Outcomes of Functional Performance Tests?

PURPOSE

Mental fatigue impairs psychomotor skill performance by affecting visuomotor reaction time, accuracy, and decision-making. Recently, neurocognitive functional performance tests (FPT) that integrate these outcomes have been developed. The aim of this study was to assess the effect of mental fatigue on traditional and neurocognitive FPT in healthy adults.

METHODS

Fourteen volunteers (four women; mean ± SD age, 22 ± 1 yr; height, 176.9 ± 8.4 cm; weight, 69.7 ± 10.4 kg) participated in a randomized counterbalanced crossover design. A 100% incongruent Stroop color word test of 90 min was used to induce mental fatigue and the control task encompassed watching a 90-min documentary. Traditional FPT comprised a single-leg hop for distance, countermovement jump, and Y-balance test, whereas the neurocognitive FPT encompassed the reactive balance test (RBT). All FPTs were evaluated pre-post the 90-min task. Mental fatigue was assessed using the Stroop task, visual analog scale for mental fatigue, and the Eriksen-Flanker task.

RESULTS

Mental fatigue was successfully induced, as shown by a significant increase in visual analog scale for mental fatigue (P < 0.001), with no decrease in performance on the Stroop and Eriksen-Flanker task. No interaction effect of mental fatigue was found for the Y-balance test, single-leg hop, and countermovement jump. For the RBT accuracy, a significant interaction effect of mental fatigue and time was observed (P = 0.024), with participants performing significantly worse when mentally fatigued. No interaction effect or main effect of condition and time was observed when considering the effect of mental fatigue on visuomotor reaction time in the RBT.

CONCLUSIONS

Mental fatigue negatively affects a neurocognitive FPT, indicated by a decreased accuracy in response to visual stimuli in the RBT. Traditional FPT remained unaffected by mental fatigue.

The Relationship between Dynamic Balance and Jumping Tests among Adolescent Amateur Rugby Players. A Preliminary Study

Rugby is a demanding contact sport. In light of research, poor balance, reduced jumping ability, muscle strength, and incorrect landing patterns might contribute to the increased risk of injury in athletes. Investigating the relationship between tests assessing these abilities might not only allow for the skillful programming of preventive training but also helps in assessing the risk of injury to athletes. Thus, the main purpose of this study was to investigate the relationship between dynamic balance, vertical and horizontal jumps, and jump-landings movement patterns. Thirty-one healthy amateur adolescent rugby players (age: 14.3 ± 1.6 years, height 171.4 ± 9.7 cm, body mass 80 ± 26 kg) participated in the study. Data were collected by the Y-balance Test (YBT), Counter Movement Jump (CMJ), Single Leg Hop for Distance (SLHD), and Landing Error Score System (LESS). Significant positive correlations were found between SLHD both legs (SLHDb) and YBT Composite both legs (COMb) (r = 0.51, p = 0.0037) and between SLHDb and CMJ (r = 0.72, p < 0.0001). A relationship was also observed between the CMJ and YBT COMb test (r = 0.51, p = 0.006). Moderate positive correlations were found between the dominant legs in SLHD and the posterolateral (r = 0.40, p = 0.027), posteromedial (r = 0.43, p = 0.014), and composite (r = 0.48, p = 0.006) directions of the YBT. These results indicate that variables that are dependent on each other can support in the assessment of injury-risk and in enhancing sports performance of young athletes.

Practicability of lower extremity functional performance tests and their measurement properties in elite athletes: protocol for a systematic review

INTRODUCTION

Lower extremity injury (LEI) is highly prevalent and its occurrence increases the risk of future injury in athletic populations. Identifying athletes at risk of injury is the key to target injury-prevention programmes. Functional performance tests (FPT) assess an athlete's ability to produce and accept forces during movement tasks reflective of those experienced in sport, and are used to identify deficits in physical qualities or neuromuscular control. This review aims to identify FPT which have potential to predict LEI and assess their measurement properties associated with reliability, validity, responsiveness and practicability (interpretability and feasibility).

METHODS/ANALYSIS

This protocol will be reported using the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol and the COnsensus-based Standards for the selection of health Measurement INstruments Methodology. The search strategy has two stages: stage 1 will identify lower limb FPT used in athletic populations; and stage 2 will assess the measurement properties of the identified FPT. A sensitive search strategy will use MEDLINE, EMBASE, CINHAL and SPORTdiscus databases; from inception to June 2020. Hand searching reference lists, key journals and grey literature will be completed. One reviewer will complete search 1 and data extraction. Two reviewers will complete the search, data extraction and risk-of-bias assessment for search 2. Evidence will be pooled or summarised by individual measurement property by each individual study and grouped by FPT. Meta-analysis using a random effects model with subgroup analysis will be performed where possible. Pooled or summarised results for each FPT in relation to each measurement property will be rated against the criteria for good measurement properties. Two reviewers will assess the overall body of evidence per measurement property per FPT using the modified Grading of Recommendations, Assessment, Development and Evaluation guidelines. This review will enable clinicians to make an informed choice when selecting FPT.

ETHICS AND DISSEMINATION

No ethical approval is required for this review and the results will be disseminated through peer-reviewed publications and submitted for conference presentation.

PROSPERO REGISTRATION NUMBER

CRD42020188932.

Predictive Validity of a Functional Movement Screen in Professional Basketball Players

Background and objectives: Striking a balance between maximizing performance and preventing injury remains elusive in many professional sports. The purpose of this study was to assess the relative risk of non-contact injuries in professional basketball players based on predictive cut scores on the Functional Movement Screen™ (FMS). Materials and Methods: Thirty-two professional basketball players from the National Basketball Association (NBA) and Women’s National Basketball Association (WNBA) participated in this study. This observational pilot cohort study assessed and scored each participant using the FMS during training camp. Each athlete was then tracked throughout the season while recording the number, type, and time lost due to injuries. Possible exposures, actual exposures, and exposures missed due to non-contact injury (NCI) for each athlete were calculated and then used to determine the crude and specific incident rates for exposures missed due to NCI per 1000 exposures. Results: Linear regression models were used to evaluate the predictive ability of the FMS score for total missed exposures, NCI, and CI missed exposures. In all models, the FMS total score failed to attain significance as a predictor (p > 0.05). FMS scores ranged from 5 to 18. The recommended cut score of 14 showed a sensitivity of 0.474 and a specificity of 0.750. The cut score of 15 showed the best combination, exhibiting a sensitivity of 0.579 and specificity of 0.625. A total of 5784 exposures to NCI were possible for the men and women combined, and 681 possible exposures were missed. Of these, 23.5% were due to NCI, 16.5% were due to contact injuries (CI), and 60% were due to illnesses and personal reasons. Conclusions: The FMS proved to be a measure that was not associated with any injury measure in this sample of professional basketball players, suggesting the instrument lacks predictive validity in this population.

Electromyographic responses of knee isokinetic and single-leg hop tests in athletes :dominant vs. non-dominant sides

The purpose of the study is to perform the electromyographic (EMG) analysis of isokinetic and single-leg hop tests (SLHTs). We included 20 healthy male athletes (age: 23.18 years, height: 178.82 cm, weight: 73.76 kg and BMI: 47 kg/m²) voluntarily. Isokinetic knee strength tests at at 60°sec^-1, 180°sec^-1, 240°sec^-1 velocities and different SLHTs; Single leg (SL), Triple leg (THD) and Crossover (CHD) hop for distance tests, 6 m timed-hop test (6 m THT), Single leg vertical jump test (VJ) were measured. Muscle activations of quadriceps (Q); vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF) and hamstring (H); biceps femoris (BF) were obtained. There were significant differences in SL, THD, CHD and VJ in DS (p < 0.05).VJ revealed a statistical significance in NDS (p = 0.003). The comparison of the activations produced by the same muscles in different tests showed statistically significant differences in all the muscles for both sides (p < 0.05). In conclusion, we determined that the muscles produce similar activations in the isokinetic tests for both the DS and NDS, whereas there are differences in some of the SLHTs. The most active muscles were VM and RF (medial muscles) in isokinetic tests, and VL (lateral muscle) in SLHTs.g.

Can Neurocognitive Function Predict Lower Extremity Injuries in Male Collegiate Athletes?

The purpose of this study is to demonstrate whether neurocognitive evaluation can confirm the association between neurocognitive level and postural control and to analyze the relationship between neurocognitive level and acute musculoskeletal injury in male non-net sports athletes. Seventy-seven male non-net sports athletes participated in this study. The Standardized Assessment of Concussion (SAC), Landing Error Scoring System (LESS), Balance Error Scoring System (BESS), and Star Excursion Balance Test (SEBT) were used for testing; we collected data related to injury history for six months after testing. Pearson's correlation analysis, logistic regression, and the independent sample t-test were used for statistical analysis. The correlation between SAC and SEBT results was weak to moderate (p < 0.05). Eleven of the seventy-seven participants experienced acute lower limb injuries. SAC, LESS, BESS, and SEBT results have no effect on the occurrence of acute lower extremity injuries (p > 0.05) and were not statistically different between the injured and non-injured groups (p > 0.05). Therefore, using the SAC score alone to determine the risk factor of lower extremity injuries, except in the use of assessment after a concussion, should be cautioned against.

Using functional movement tests to investigate the presence of sensorimotor impairment in amateur athletes following sport-related concussion: A prospective, longitudinal study

OBJECTIVE

To longitudinally investigate the presence of sensorimotor impairments in amateur athletes following sport-related concussion using two functional movement tests.

DESIGN

Prospective, longitudinal study.

SETTING

Human movement analysis laboratory.

PARTICIPANTS

Athletes who presented to a hospital emergency department and were diagnosed with sport-related concussion, and sex-, age-, and activity-matched non-concussed, control athletes. Concussed participants were assessed within one-week following sport-related concussion, upon clearance to return-to-sporting activity (RTA), and two weeks after RTA. Control participants were assessed at an initial time-point and approximately two and four weeks following their initial study assessment.

MAIN OUTCOMES MEASURES

At each laboratory assessment, participants completed two functional movement tests: the Star Excursion Balance Test to evaluate anterior reach distance (normalised for leg length) and fractal dimension (centre of pressure path complexity), and the Multiple Hop Test to evaluate corrective postural strategies and time-to-stabilisation.

RESULTS

Fifty concussed athletes and 50 control athletes completed the study. There were no significant differences at any study assessment between the concussion and control group on the Star Excursion Balance Test anterior reach distance or fractal dimension (centre of pressure path complexity). During the Multiple Hop Test, the concussion group used a significantly greater number of corrective postural strategies than the control group one-week following sport-related concussion and upon clearance to RTA, but not two weeks following RTA.

CONCLUSION

Recently concussed athletes made a greater number of corrective postural strategies than control participants during the Multiple Hop Test upon clearance to RTA but not two weeks after RTA. The Multiple Hop Test may offer a clinically useful tool for practitioners to examine the recovery of subtle sensorimotor impairments and related RTA readiness.

Lower limb kinematics and hip extensors strengths are associated with performance of runners at high risk of injury during the modified Star Excursion Balance Test

BACKGROUND

Reduced trunk and lower limb movement and hip and trunk muscles weakness may compromise the athletes' performance on the modified Star Excursion Balance Test (mSEBT).

OBJECTIVE

To investigate the relationship of trunk and lower limb kinematics and strength with the performance on the mSEBT of runners at high risk of injury.

METHODS

Thirty-nine runners performed the mSEBT with the dominant limb as the support limb. An Inertial System was used to capture the trunk, hip, knee and ankle movement during the mSEBT. A handheld dynamometer was used to measure the strength of trunk extensors and lateral flexors muscles, and hip extensors, lateral rotators and abductors of the support limb. Multiple regressions were used to investigate if trunk and lower limbs kinematics and trunk and hip muscles strength are associated with performance during the mSEBT.

RESULTS

Reduced hip flexion and greater knee flexion range of motion (ROM) were associated with anterior reach in the mSEBT (r2=0.45; p<.001), greater hip flexion ROM was associated with posteromedial reach (r2=0.15; p=.012) and greater knee flexion ROM was associated with posterolateral reach (r2=0.23; p<.001). Hip extensor strength was associated with posteromedial (r2=0.14; p=.017), posterolateral (r2=0.10; p=.038) and composite reaches (r2=0.16; p=.009).

CONCLUSION

Hip and knee kinematics in the sagittal plane explained 15-45% of the runners' performance on the mSEBT and hip extensor strength explained 10-16% of the mSEBT performance. These findings provide useful information on the contribution of joints kinematics and strength when evaluating dynamic postural control in runners at high risk of injury.

Higher Vertical Jumping Asymmetries and Lower Physical Performance are Indicators of Increased Injury Incidence in Youth Team-Sport Athletes

Fort-Vanmeerhaeghe, A, Milà-Villarroel, R, Pujol-Marzo, M, Arboix-Alió, J, and Bishop, C. Higher vertical jumping asymmetries and lower physical performance are indicators of increased injury incidence in youth team-sport athletes. J Strength Cond Res XX(X): 000-000, 2020-To date, the literature about the association between injury-risk factors and actual injury incidence in young elite team-sports athletes is scarce. The main objective of this study was to examine how modifiable factors may affect injury incidence. Eighty-one young elite team-sports athletes (age: under-14 to under-18) performed the countermovement jump (CMJ), a single leg CMJ (SLCMJ), the one-legged hop test (OLHT), a 30-m sprint test, the V-cut test, a repeated sprint ability, and the 30-15 intermittent fitness test (IFT) during the pre-season period. Interlimb asymmetries were calculated for SLCMJ and OLHT. Injuries were recorded prospectively for the entirety of the 2017-2018 season. Comparison of injury and noninjury data was performed using a two-way analysis of variance (ANOVA). Results of the ANOVA according to injury showed significant differences in CMJ (p = 0.01), SLCMJ on the lowest performing limb (p = 0.03), and SLCMJ asymmetry (<0.001). Sex × injury interaction was significant from CMJ (p = 0.018) and 30-15 IFT (p = <0.001). In conclusion, this study indicated that athletes with greater interlimb asymmetries, less vertical jump capacity, and lower intermittent aerobic fitness had a greater predisposition to injury. Therefore, monitoring CMJ, aerobic performance, and interlimb asymmetries is recommended given their sensitivity to detect significant differences between injured and healthy youth athletes.

Utility of the anterior reach Y-BALANCE test as an injury risk screening tool in elite male youth soccer players

OBJECTIVES

Examine growth and maturation trends in dynamic balance using the anterior reach Y-Balance test, and its utility as an injury risk screening tool.

DESIGN

Cross sectional and prospective cohort.

SETTING

Elite male youth soccer players.

PARTICIPANTS

346 players grouped as pre, circa or post peak height velocity (PHV).

MAIN OUTCOME MEASURES

Pre-season anterior reach absolute and relative Y-Balance test scores and seasonal prospective lower extremity injury monitoring.

RESULTS

Absolute reach distances were greatest post-PHV (p < 0.05). Relative to leg length, pre-PHV achieved the highest scores and increased between-limb differences. Significant associations between injury and anterior reach scores were present in pre (OR: 0.94, CI: 0.91-0.98, p < 0.05) and circa-PHV (OR: 1.05, 95% CI: 1.05-1.10, p < 0.05). Increased age (OR: 1.49, 95% CI: 1.04-2.13, p < 0.05) and height (OR: 1.06, 95% CI: 0.99-1.13, p = 0.82) were risk factors post-PHV. No differences in injury occurrence were shown between players with absolute reach difference >4 cm in any group.

CONCLUSIONS

Anterior reach scores increased injury risk, but associations were small and inconsistent. The Y-Balance should be used with caution as a screening tool in this cohort.

The Association Between the Single Leg Hop Test and Lower-Extremity Injuries in Female Athletes: A Critically Appraised Topic

Clinical Scenario: Female college student-athletes (SA) often experience time loss from musculoskeletal injuries to the lower extremities. This can lead to lengthy rehabilitation, expensive medical bills, and declines in health-related quality of life. Identifying at-risk athletes prior to the start of an athletic season may allow coaches or athletic trainers to prescribe an injury prevention program. Clinical Question: In female college SA, are preseason single leg hop (SLH) scores associated with identifying those at risk for lower-extremity musculoskeletal injuries? Summary of Key Findings: Five prospective cohort studies in female SA scored athletes on the SLH prior to the start of the athletic sport season. One of 5 studies found an association of SLH with injury risk. An additional 2 studies found that the SLH as part of a battery of functional performance tests was associated with injury risk in some anatomic locations (eg, thigh/knee), but not overall injury risk. Clinical Bottom Line: Methodological limitations of the reviewed studies limits a final conclusion, and there is insufficient evidence to determine if the SLH should be used as a sole functional performance test to identify at-risk female SA; it may be useful as part of a battery of functional performance tests for female college SA. Strength of Recommendation: All studies were prospective cohort studies (level 3).

Use of the lower extremity functional test to predict injury risk in active athletes

BACKGROUND

The purpose of the current study was to assess the reliability and validity of the lower extremity functional test (LEFT) for predicting low back and lower limb injury in active athletes.

METHODS

Seventy athletes (45M, 25F; mean age: 21±2 years) from seven different sports volunteered. The LEFT was a battery of five weight-bearing functional movements involving different movement planes, directions, modes, and at varying intensities. Both legs were assessed in a random order and each athlete was given both movement quality and associated symptom scores. Intratester, intrarater and inter-rater reliability were evaluated. Participants were followed up for 12 months, and their exposure to sport and subsequent injuries were recorded. Independent samples t-tests were performed to determine if a significant difference existed in LEFT scores between injured and non-injured athletes. Receiver operating characteristic (ROC) curve analysis was employed to assess the instrument's capacity to predict injury.

RESULTS

The intratester reliability ICC2, 1 was 0.875. The ICC2, 3 of intrarater reliability was 0.953 and the inter-rater reliability was 0.949, respectively. Nineteen participants had an injury in the low back or lower limb within the following 12 months. Injured athletes had significant lower movement quality and symptom scores of the LEFT than non-injured (t=4.278, P=0.000, Cohen's d=1.2; t=3.654, P=0.001, Cohen's d=1.3, respectively). When movement quality or symptom score alone was included in the ROC analysis, the area under the ROC curve (AUC) scores were 0.772 (P=0.000, 95% CI: 0.653-0.891) and 0.771 (P=0.001, 95% CI: 0.638-0.905), respectively. When movement quality and symptom scores were combined to predict injury, the AUC discrimination score was 0.853 (P=0.000, 95% CI: 0.754-0.953), resulting in 85.3% of cases being correctly predicted as low back or lower limb injured/noninjured.

CONCLUSIONS

The findings from the current study suggest that the LEFT appears to be a reliable and valid functional assessment tool for predicting low back or lower limb injury risk in these college athletes, especially when movement quality and symptom scores were used in combination.

Systematic review of motor control and somatosensation assessment tests for the ankle

Background/Aim

Ankle sprains are frequent musculoskeletal injuries that can lead to sensorimotor deficits provoking long-term instability at the ankle joint. A broad variety of clinical tests currently exist to assess sensorimotor processing, and are commonly clinically referred to as proprioceptive tests. However, there is a discrepancy in the use of the term proprioception when looking at the main outcome of these tests. As identifying specific deficits is important for motor recovery, it is critical for clinicians to select the most appropriate tests.

Methods

A systematic review of four databases was performed to provide an up-to-date review of the psychometric properties of available tests referred to as proprioceptive tests. Seventy-nine articles on eight ankle proprioceptive tests were included and critically appraised. Data on validity, reliability and responsiveness were extracted from the included articles and synthesised. The tests reviewed were then divided into two categories based on their main outcome: motor control or somatosensation.

Results

Strong evidence showed that the Star Excursion Balance Test, a motor control test, is capable of differentiating between stable and unstable ankles. Moderate evidence suggests that somatosensation tests, such as Joint Position Sense, are also valid and reliable, but their responsiveness has yet to be evaluated.

Conclusions

Together, these findings indicate that the Star Excursion Balance Test can be used in the clinic to assess motor control based on its excellent psychometric properties. However, as ankle stability control involves complex sensorimotor interactions, care has to be taken regarding the use of this test as a specific tool for proprioception assessment.

Criteria-Based Return to Sport Decision-Making Following Lateral Ankle Sprain Injury: a Systematic Review and Narrative Synthesis

OBJECTIVE

The aim of this systematic review was to identify prospective studies that used a criteria-based return to sport (RTS) decision-making process for patients with lateral ankle sprain (LAS) injury.

DESIGN

Systematic review and narrative synthesis.

DATA SOURCES

The PubMed (MEDLINE), Web of Science, PEDro, Cochrane Library, SPORTDiscus (EBSCO), ScienceDirect, and Scopus databases were searched to 23 November 2018.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies were included if they prospectively applied a criteria-based RTS decision-making process for patients with LAS injury, but were excluded if they merely gathered outcome measures at the RTS time point. Studies were also excluded if patients were recovering from ankle fracture, high ankle sprain, medial ankle sprain, chronic ankle instability or complex ankle injury.

RESULTS

No studies were identified that used a criteria-based RTS decision-making process for patients with LAS injury. We were unable to conduct a quantitative synthesis or meta-analysis, therefore we provide a narrative synthesis of relevant questionnaires, as well as clinical and functional assessments commonly used in studies retrieved in the search.

CONCLUSION

There are currently no published evidence-based criteria to inform RTS decisions for patients with an LAS injury. Based on our narrative synthesis, we propose a number of variables that could be used to develop a criteria-based RTS decision paradigm. Future research should aim to reach consensus on these variables and apply them to actual RTS decisions within prospective study designs. Furthermore, we suggest that complex systems theory and the RTS continuum could be used to inform the development of an RTS decision-making paradigm for athletes with LAS injury.

Myoelectric Responses of Lower-Body Muscles Performing Squat and Lunge Exercise Variations Adopting Visual Feedback With a Laser Sensor

STUDY DESIGN

Cross-over study.

CONTEXT

The squat, single-leg squat, forward lunge, and reverse lunge are fundamental movements often performed in activities of daily living, sports competitions, and sport-specific training.

OBJECTIVE

The purpose of this study was to investigate the effect of visual feedback with a laser sensor (VFLS) versus a control condition on the myoelectric activity (surface electromyography [sEMG]) of the vastus medialis oblique (VMO), vastus lateralis, gluteus medius (Gmed), and erector spinae muscles during the performance of several squat variations with bodyweight.

METHODS

Nineteen female college students (20 [2.5] y, 165.3 [10.2] cm, 66.4 [4.1] kg, 2 [1.2] y of resistance training experience) with a background in strength or sports training volunteered to participate in this study. Over 4 separate visits, subjects performed 2 sets of 10 repetitions of a squat variation exercise in random order (ie, squat, single-leg squat, forward lunge, and reverse lunge). The first set of a given squat variation condition was considered a control set, and then after 3-minute rest, a second set was performed with VFLS.

RESULTS

Significant decreases in VMO and Gmed myoelectric activity were observed during the VFLS set versus the control set for the forward lunge exercise (P = .03). No differences were observed between the control set and VFLS set in the sEMG normalized signal for all muscles analyzed for the squat and single-leg squat, respectively. However, the sample entropy of the sEMG signal for the erector spinae became more irregular during the VFLS set versus the control set for the squat exercise (P = .01), whereas the Gmed presented a more irregular sEMG signal during the VFLS set versus the control set for the single-leg squat (P = .08).

CONCLUSION

Laser sensor biofeedback may induce significant decreases in VMO and Gmed activation performing forward lunge exercise. Therefore, laser sensor biofeedback may induce a reduction in muscle activity of neutralizers muscles during a few squat bodyweight variations (bilateral, single-leg, forward, and reverse lunge).

Dynamic balance and ankle injury odds: a prospective study in 196 Dutch physical education teacher education students

OBJECTIVE

The aim of this study was to investigate whether dynamic balance, measured with the anterior component of the Star Excursion Balance Test (SEBT-ANT), is a risk factor for ankle injuries in physical education teacher education (PETE) students.

DESIGN AND SETTING

A prospective monocentre study in first-year PETE students.

PARTICIPANTS

A total of 196 subjects, of which 137 men (70%) and 59 women (30%).

OUTCOME MEASURES

This study consisted of measures of the SEBT-ANT at baseline (September 2015) and an injury registration procedure during a follow-up period (September 2015-June 2016). The association between the SEBT-ANT score and subsequent ankle injury was analysed with generalised estimating equations analysis at the leg level.

RESULTS

Men and women had an average SEBT-ANT score of, respectively, 65.1% and 67.7% of leg length. In 20 (15%) subjects, the first injured body site involved the ankle. Across all participants, a below average SEBT-ANT score was not associated with increased ankle injury odds (OR OR=2.43, 95% CI: 0.94 to 6.29, p=0.07). In men, a below average SEBT-ANT score indicated sevenfold increased odds for ankle injury (OR=7.06, 95% CI: 1.43 to 34.92, p=0.02). In women, this relationship was not significant (OR=0.72, 95% CI: 0.19 to 2.71, p=0.62).

CONCLUSIONS

Below average normalised SEBT-ANT scores were associated with sevenfold likelihood for ankle injuries in men. In contrast, no relationship was found for the SEBT-ANT score and ankle injuries in woman. These results may provide directions for the implementation of screening tools, as part of an injury prevention programme, to identify male PETE students with an increased likelihood for ankle injuries.

Single-Leg Squat Performance and Its Relationship to Extensor Mechanism Strength After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Performance in strength and functional testing is important when considering return to sport after anterior cruciate ligament (ACL) reconstruction. Both knee extensor strength and the single-leg squat (SLS) have been used in this context.

PURPOSE

To evaluate the relationship between knee extensor strength and SLS performance after primary ACL reconstruction.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 3.

METHODS

A prospective cohort of 100 patients was assessed 6 and 12 months after primary ACL reconstruction with a hamstring tendon autograft. Knee extensor peak torque was measured. Three sequential SLSs were performed, and the maximum flexion angle identified from frame-by-frame video analysis was used as the measure of squat performance. A limb symmetry index (LSI) was calculated and satisfactory performance defined as ≥90%.

RESULTS

Extensor mechanism strength deficits were seen in 75% of patients at 6 months and 57% at 12 months postoperatively. Mean extensor mechanism strength showed a large improvement between 6 and 12 months (123.6 vs 147.8 N·m, respectively; P < .001; Cohen d = 1.10), and while there was also a statistically significant improvement in the mean maximum flexion angle, the change was small (66.1° vs 68.1°, respectively; P = .011; Cohen d = 0.26). There was a weak positive correlation between knee extensor strength and the SLS maximum flexion angle at 6 months (r = 0.342; P < .001) and 12 months (r = 0.245; P = .014). An SLS LSI <90% was 80% specific and 35% sensitive for extensor mechanism weakness at 6 months and 79% specific and 18% sensitive at 12 months.

CONCLUSION

Extensor mechanism strength deficits are common after ACL reconstruction but reduce between 6 and 12 months. The SLS maximum flexion angle has a weak linear relationship to knee extensor strength. SLS performance has high specificity but low sensitivity in identifying extensor mechanism strength deficits. The SLS maximum flexion angle is therefore a suboptimal surrogate test to identify extensor mechanism strength deficits as diagnosed by isokinetic dynamometric testing. However, unsatisfactory SLS performance indicates a very high chance of underlying extensor mechanism weakness.

The predictive value of the multiple hop test for first-time noncontact lateral ankle sprains

The predictive value of the multiple hop test for first-time noncontact lateral ankle sprains.

BACKGROUND

Lateral ankle sprains (LAS) are very common sports injuries, cause high health care costs and are associated with postural control deficits. From a preventive point of view, clinicians should dispose valid field tests to identify athletes at risk for a LAS. The aim of this study is to evaluate the predictive value of the multiple hop test (MHT) for first-time noncontact LAS.

METHODS

Non-elite athletes (n = 232) performed the MHT at baseline. During a 12-month follow-up period, all noncontact LAS related to health care costs were recorded. Outcomes of the MHT (completion time, balance errors and perceived difficulty) between the injured and uninjured group were compared and odds ratios (OR) and relative risks (RR) were calculated using a logistic regression analysis.

RESULTS

Ten first-time noncontact LAS were recorded (4.3%). Injured athletes made significantly more change-in-support strategy (CSS) errors when compared to uninjured athletes (p = .04). The OR of the number of CSS errors was 1.14 (p = .03), the RR 4.1 (p = .04).

CONCLUSIONS

Athletes scoring > 12 CSS errors, have a four times increased risk for a first-time noncontact LAS. The MHT is a valid field test to identify athletes at risk for a first-time noncontact LAS.

Is a low Functional Movement Screen score (≤14/21) associated with injuries in sport? A systematic review and meta-analysis

Objective

To assess whether Functional Movement Screen (FMS) score is associated with subsequent injuries in healthy sportspeople.

Design

Systematic review and meta-analysis.

Data sources

The following electronic databases were searched to December 2017: Medline, PubMed, PsycINFO, SPORTDiscus, Cumulative Index of Nursing and Allied Health Literature, Scopus, Embase, and Physiotherapy Evidence Database.

Eligibility criteria for selecting studies

Eligibility criteria included (1) prospective cohort studies that examined the association between FMS score (≤14/21) and subsequent injuries, (2) a sample of healthy and active participants without restrictions in gender or age, and (3) the OR was the effect size and the main outcome.

Results

Thirteen studies met the criteria for the systematic review and 12 were included in the meta-analysis. In 5 of the 12 studies, and among female athletes in 1 study, FMS score ≤14 out of 21 points was associated with subsequent injuries. The overall OR of the selected studies in the meta-analysis was 1.86 (95% CI 1.32 to 2.61) and showed substantial heterogeneity (I²=70%).

Summary/Conclusion

Whether or not a low FMS score ≤14 out of 21 points is associated with increased risk of injury is unclear. The heterogeneity of the study populations (type of athletes, age and sport exposure) and the definition of injury used in the studies make it difficult to synthesise the evidence and draw definitive conclusions.

Trial registration number

CRD42015015579.

Association of pre-season musculoskeletal screening and functional testing with sports injuries in elite female basketball players

Basketball is one of the most popular sports in Lithuania, and participation in women’s basketball is on the rise. Pre-participation examinations, including musculoskeletal screening and functional performance testing, is an essential part of a multidisciplinary approach to prevent future injuries. Because the lower extremities are the most commonly-injured body area in basketball players. Assessing fundamental movement qualities is of utmost importance. The aim of our study was to determine if functional tests can predict sports injuries in elite female basketball players. A total of 351 records for professional female basketball players were screened during 2013–2016 season. We analysed functional characteristics before the season and used functional performance tests for injury risk assessment: the Functional Movement Screen (FMS), the lower quarter Y Balance test (YBT-LQ) and the Landing Error Scoring System (LESS). Data from 169 players’ records were analysed: 77 of them made it to the end of season without injury, making up the non-injured group, while 92 of them suffered lower limb sport injuries during the sport season (injury group). Student’s t-test and the Mann-Whitney U-test were used to determine differences between groups. The most commonly encountered sports injuries in our population were those of knee 40.2% and ankle 38%. The injury group had a lower total FMS score (p = 0.0001) and higher total LESS score (p = 0.028) than non-injury group. The dynamic balance of lower limbs was similar in both groups. Imperfect functional movement patterns and poor jump-landing biomechanics during pre-season screening were associated with lower extremity injuries in elite female basketball players. Impairments of dynamic stability in the lower extremities were not associated with injury rates in our population. A combination of functional tests can be used for injury risk evaluation in female basketball players.