Systematic Review and Meta-Analysis of the Y-Balance Test Lower Quarter: Reliability, Discriminant Validity, and Predictive Validity

Decoding injury risk: Exploring the impact of asymptomatic hypermobility on lower limb injury risk factors in young female volleyball players

Generalized hypermobility is associated with higher rates of musculoskeletal injuries, a trend also observed in volleyball. We aimed to investigate how asymptomatic hypermobility affects other suggested lower limb injury risk factors. Fifty female volleyball players (22 hypermobile, 28 non-hypermobile) were assessed using Beighton scores (BS) and lower limb injury risk factors based on the Landing Error Scoring System, single-leg dynamic balance, and Limb Symmetry Index (LSI) for single-leg hop and triple hop for distance. Spearman's correlations assessed relationships between BS and the risk factors, and t-tests or Mann-Whitney U tests compared risk factors between non-hypermobile and asymptomatic hypermobile groups. No significant associations were found between BS and most risk factors, except for a negative correlation with the centre of pressure range of motion in the medio-lateral direction during dynamic balance on the non-dominant leg (ρ = -0.332; p = 0.015). The only significant group difference was in the LSI for single-leg hop distance, where the hypermobile group showed greater symmetry (r = 0.28, p = 0.041). The association between BS and dynamic balance was weak, with no clear difference in injury risk factors were observed between groups, suggesting hypermobile players may not need specialized training programs.

The sport function subscale of the Copenhagen Hip and Groin Outcome Score could not be an indicator of postural balance in soccer players with groin pain

OBJECTIVE

This study aimed to investigate the association between the Copenhagen Hip and groin outcome score (HAGOS) related to sport and recreation (Sport/Rec) and static and dynamic postural balance in soccer players with groin pain. We hypothesized that better postural balance outcomes would correlate with higher HAGOS Sport/Rec scores in these players.

METHODS

Eighty-four soccer players with groin pain from seven soccer teams volunteered to take part in the study. An investigator collected static (stabilometric platform) and dynamic (Y-Balance Test (Y-BT)) postural balance, and patient-reported outcome measures (HAGOS) in the research laboratory. To investigate the association between the postural balance outcomes and the HAGOS Sport/Rec scores, Spearman's correlation coefficient (r) was used.

RESULTS

The included participants presented the following demographic information: age: 21.56 yrs (2.22), height: 1.78 m (0.06), body mass: 75.10 kg (8.41), body mass index: 23.80 km/m2 (2.50). The HAGOS Sport/Rec scores showed a small significant positive correlation with the posteromedial reach distance for the Y-BT on both injured (r =0.21, p=0.04) and non-injured (r =0.22, p=0.04) limbs. However, no significant associations (p>0.05) were found between these scores and the other Y-BT outcomes, nor with the static bipedal and unipedal postural balance findings.

CONCLUSION

Overall, the findings of the present study showed only small positive correlations between the posteromedial direction of the Y-BT and HAGOS Sport/Rec scores. Given the observed small magnitude of correlations and the non-significant associations between the HAGOS Sport/Rec scores and the rest of the Y-BT outcomes or static postural balance outcomes, it appears that Sport/Rec may not serve as a comprehensive indicator for postural balance outcomes. Therefore, coaches and clinicians should consider combining postural balance assessments with HAGOS Sport/Rec scores to comprehensively tailor their interventions to address both the subjective and objective functional aspects of groin pain in soccer players.

LEVEL OF EVIDENCE: 3

The Reliability and Validity of the Modified Butterfly Agility Test

Background

No gold standard criteria exist for return to sport decision-making. The Butterfly Agility Test (BAT) has been shown to be a valid and reliable test for assessing various aspects of athletic performance; however, the space required to conduct it may be prohibitive for clinical environments and it has not been validated among an athletic population.

Purpose

To determine the reliability of the modified BAT (mBAT) and the number practice trials required to optimize its reliability. A secondary purpose was to assess the preliminary validity of the mBAT associated with the Y-Balance Test (YBT) and its relationship with player position among competitive soccer athletes.

Study Design

Multi-phase reliability and validity study.

Methods

Phases I and II involved 25 healthy adults (72% female, mean age = 23.4 years) and 45 competitive soccer athletes (55% female, mean age = 18.2 years), respectively. In Phase I, subjects performed 10 consecutive trials of the mBAT to assess test-retest and inter-rater reliability of the mBAT. In Phase II, subjects completed two consecutive trials of the mBAT and YBT during the pre-season period. Intraclass correlation coefficients were used to assess the reliability of the mBAT and repeated measures analysis of variance (ANOVA) was used to assess differences between trials in Phase I. In Phase II, Pearson's product-moment correlation coefficient was used to assess the relationship between mBAT and YBT performance and an ANOVA was used to assess differences in mBAT and YBT performance between player positions.

Results

In Phase I, the mBAT demonstrated excellent reliability (ICC = 0.92-1.00). In Phase II, female collegiate athletes performed better than male high-school athletes on the mBAT (p = 0.01). No significant relationships were found between the mBAT or YBT with player position (p > 0.26).

Conclusion

The mBAT is a reliable physical performance test and three practice trials are recommended prior to recorded trials. The validity of the mBAT for distinguishing athletic performance remains inconclusive, although it appears the mBAT measures a distinct aspect of physical performance compared to the YBT. Although this data is preliminary, the mBAT shows promise as a useful tool for clinicians, trainers, and coaches to assess physical performance among competitive soccer athletes. Larger prospective studies are warranted prior to utilizing the mBAT for clinical decision-making.

Level of Evidence

3b.

Synergistic Effects of Joint-Biased Rehabilitation and Combined Transcranial Direct Current Stimulation (tDCS) in Chronic Ankle Instability: A Single-Blind, Three-Armed Randomized Controlled Trial

Background/Objectives: The ankle joint is among the most frequently injured joints in daily life, with approximately 25% of young adults reporting chronic ankle instability (CAI). This study investigated the effects of transcranial direct current stimulation (tDCS), a type of non-invasive brain stimulation (NIBS) technique, combined with joint mobilization and active joint mobilization on CAI. Methods: A total of 36 participants (mean age: 20.81 years; 63.89% female; mean body mass index: 21.68) were randomly divided into three groups: (1) tDCS with joint mobilization (n = 12); (2) active joint mobilization (n = 12); and (3) tDCS with active joint mobilization (n = 12). Dynamic balance, range of motion (ROM), static balance, and ankle instability (Cumberland Ankle Instability Tool, CAIT) were evaluated at multiple time points. Interventions were conducted three times per week, for 15 min per session, over four weeks (12 sessions total). Results: All three groups showed significant improvements over time in dynamic balance, ankle instability, ROM, and static balance (p < 0.05). However, no significant interaction effects were observed between time and group (p > 0.05). The tDCS with active joint mobilization group demonstrated the largest effect sizes across most outcome measures, particularly for ankle instability, ROM, and static balance, in both immediate and post-intervention assessments. Conclusions: tDCS combined with active joint mobilization appears to be particularly effective in improving CAI. This approach, targeting both top-down mechanisms through non-invasive brain stimulation and local joint function, offers a promising alternative to traditional interventions that focus solely on the ankle joint. This study was registered with the Clinical Research Information Service (CRIS) under the identifier KCT0009566.

Effects of tape and Kinesiotape on ankle range of motion, Single Leg Drop Jump and balance after running-induced fatigue: a cross-over clinical trial

The prevention and management of injuries in runners is a key area of research in sports medicine. Fatigue during running can lead to biomechanical imbalances and inhibition of stabilizing muscles, increasing the risk of injury. With the ankle being the most commonly injured joint in runners, rigid tape (RT) and Kinesiotape (KT) have been proposed as effective methods to improve joint stability and reduce injury risk. The objective of this study was to compare the effects of a KT and RT and no tape (control group) on lower limb balance, ankle dorsiflexion ROM, and electromyographic (EMG) activation of the pronator and supinator muscles of the ankle during a Single Leg Drop Jump (SLDJ) following a treadmill fatigue protocol. From March 1st until April 10th, 2024, a cross-over clinical trial with three conditions: control group, with a RT, and with KT was conducted with n = 22 well-trained runners aged 29.29 ±  10.98 years. Lower limb stability, ankle dorsiflexion mobility, SLDJ parameters, and electromyographic activation of the ankle muscles (tibialis anterior (TA), extensor digitorum longus (EDL), peroneus longus (PL), and medial gastrocnemius (MG)) during a SLDJ were analyzed Pre and Post fatigue protocol, involving a 30-minute run at 85% of the maximal aerobic speed on a treadmill. Statistical analysis was conducted using repeated-measures ANOVA with Bonferroni correction. The RT bandage decreased ankle dorsiflexion ROM compared to both KT bandage and a control group during pre fatigue treadmill protocol measurements in the lunge and Y Balance Tests (specifically in the anterior direction). Group-by-time interaction showed significant differences for the lunge test (p =  0.045), SLDJ height (p =  0.014), flight time (p =  0.019) and ground contact time (p =  0.035). With the RT condition, the runners exhibited higher peak activation of the EDL muscle compared to the KT and control group during initial landing (p =  0.028), with a lesser decay in activation during take-off (p =  0.016). The KT showed a significant increase in the activation of the PL muscle during the first contact phase of the SLDJ (p =  0.046). Concerning flight and contact time during the SLDJ, both KT and RT proved beneficial in mitigating fatigue symptoms before and after the treadmill protocol. Regarding the RT bandage's specific effects on muscle activation, our findings indicate that the RT group exhibited higher peak activation of the EDL muscle compared to the KT and control groups during initial landing, with a lesser decay in activation during take-off. The KT showed a significant increase in the activation of the PL muscle during the first contact phase of the SLDJ. To conclude, our study highlights the potential benefits of both KT and RT in reducing fatigue symptoms during SLDJ. The study was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12624000099527) on February 2nd, 2024 (https://anzctr.org.au/).

Sports injury risk assessment based on a training and functional movement analysis of young elite equestrian athletes- an exploratory cross-sectional study

BACKGROUND

Dressage and show jumping is a high-risk sport, especially for young and professional riders.

OBJECTIVE

To analyze hip flexibility and strength, dynamic body balance, functional movement and pelvic obliquity in junior elite equestrian athletes as potential targets for future preventive measures.

DESIGN

A single-center cross-sectional study.

METHODS

Members of an elite junior equestrian team (N = 12) underwent standardized interviews, basic orthopedic examinations, lower quarter Y-balance testing (YBT-LQ), functional movement screening (FMS), and hip abductor/adductor strength measurements. Analysis of covariance (ANCOVA), a linear mixed model, and univariable logistic regression were used.

RESULTS

General medical issues were reported by 83.3% and orthopedic issues by 66.7% of the participants. For the YBT-LQ test, the mean composite score was 89.6% ± 8.0%, and maximally reached distances in one direction of movement varied between 0.1 and 5.4 cm between the right and left legs. Posteromedial reached distances were significantly influenced (p =.031) by years of training in equestrian sports. Participants achieved an average of 15.2 ± 1.9 points in the FMS, and two had scores below 14. Hip strength measurements showed 8-19% stronger adductors than abductors. Hip flexion contractures were identified in all show jumping athletes.

CONCLUSION

The results focus on the imbalances that can pose a high risk of injury. In particular, in future training concepts and preventive efforts, imbalance should be addressed in the Y-balance test, hip muscles with stronger adductor than abductor, and hip flexion contracture.

Relationship Between Shoulder Rotation Strength and Upper Extremity Functional Assessments in Collegiate Baseball Players

Background/Objectives: In overhead throwing sports such as baseball and softball, upper extremity injuries are prevalent at both collegiate and high school levels. Currently, there is no universal assessment protocol to identify athletes at risk for injury or to determine their readiness to return to sport. This study aimed to investigate the relationship between shoulder internal rotation (IR) and external rotation (ER) isometric strength in a throwing position and three upper extremity functional tests among collegiate baseball players. It was hypothesized that there would not be significant correlations between shoulder IR and ER peak isometric force and the following functional assessments: the Upper Quarter Y Balance Test (YBT-UQ), seated single-arm shot put, and Closed Kinematic Chain Upper Extremity Strength Test (CKCUEST). Methods: Forty healthy collegiate baseball players volunteered for the study. After completing a self-guided warm-up, participants performed bilateral isometric shoulder IR and ER strength tests at 90 degrees of shoulder abduction and elbow flexion, followed by the three functional tests in random order. Relationships were analyzed using Pearson's correlation coefficients (r), with a significance level set at p < 0.05. Results: Correlations were generally low, ranging from r = 0.001 to r = 0.551. Significant correlations were observed between the CKCUEST and dominant IR strength (r = 0.345, p = 0.031), dominant ER strength (r = 0.407, p = 0.010), and non-dominant ER strength (r = 0.551, p < 0.001). Additionally, a significant correlation was found between the dominant ER/IR strength ratio and the dominant arm superolateral reach on the YBT-UQ (r = -0.352, p = 0.026). No significant correlations were identified between isometric shoulder strength and the single-arm shot put. Conclusions: Most correlations were low to moderate, and only significant correlations between shoulder rotation isometric strength and one direction of the YBT-UQ and the CKCUEST were observed. Thus, shoulder rotation strength in a position similar to the cocking phase of overhead throwing may be valuable for return-to-sport criteria and injury screening for overhead athletes. However, further research is needed to validate these findings.

Modified Star Excursion Balance Testing at 12 Months After Anterior Cruciate Ligament Reconstruction: Is There a Difference Between Quadriceps or Hamstring Tendon Autografts?

Background

Quadriceps tendon (QT) autograft has emerged as an increasingly popular graft for anterior cruciate ligament reconstruction (ACLR). The modified Star Excursion Balance Test (MSEBT) measures dynamic balance and is frequently used in evaluating preparedness to return to sport as part of return-to-sport test batteries. There is limited information available about the MSEBT performance of patients who have undergone ACLR with QT autograft.

Hypothesis/Purpose

The purpose was to compare the MSEBT performance at 12 months after primary ACLR of patients with QT autografts with the performance of patients with hamstring tendon (HS) autografts. It was hypothesized that there would be a difference in the 2 groups due to harvest from either an extensor or a flexor of the knee joint.

Study Design

Cohort study; Level of evidence, 3.

Methods

The cohort consisted of 132 patients (44 patients with QT, 88 patients with HS) who had undergone primary ACLR with either a QT or HS autograft, were <30 years of age at the time of surgery, and had participated in sports regularly before injury. Patients with contralateral anterior cruciate ligament injury or an additional lateral extra-articular tenodesis were excluded. The mean age of the patients was 22.1 years, and 18% were female. The anterior reach, posterolateral reach, and posteromedial reach on the MSEBT were recorded at 12 months postoperatively and normalized to leg length. The limb symmetry index (LSI) and the composite score (CS) were calculated for each measurement. Patient-reported outcome measures were also collected.

Results

There were no significant differences between the mean LSI and the CS of the QT and HS groups for any reach direction of the MSEBT (LSI: QT = 99.9 and HS = 98.9 for anterior reach, QT = 100.9 and HS = 100.2 for posterolateral reach; QT = 101.1 and HS = 100.8 for posteromedial reach, CS: QT = 96.6 and HS = 96.9). Patient-reported outcome measures also showed no significant difference.

Conclusion

There were no differences in symmetry between QT and HS grafts in MSEBT performance at 12 months, with both patient groups having >98% limb symmetry in each reach direction.

Assessing the Predictive Value of Preoperative Knee Function Tests and Self-Report Scores in Anterior Cruciate Ligament Injury Recovery

BACKGROUND

The ability to identify patients with long-term poor outcomes using clinical and functional information is limited. Identifying prognostic factors to improve long-term outcomes after anterior cruciate ligament (ACL) injury can influence and inform targeted interventions for this population.

HYPOTHESIS

Preoperative functional tests and patient-reported outcome measures are predictive of postoperative functional recovery and satisfaction in patients undergoing first-time ACL repair, second-time ACL repair on the same knee, and bilateral ACL repair.

STUDY DESIGN

Quasi-experimental prospective study.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 88 patients with ACL reconstruction were included. Subjective knee scoring systems and functional performance tests were used for evaluation and analyzed for correlation with results.

RESULTS

The first time ACL injury group had lower scores in the various self-report scales: Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm Rating Scale, International Knee Documentation Committee (IKDC), and Lower Extremity Functional Scale (LEFS).

CONCLUSION

Reduction in self-reported knee function and Y balance test performance after ACL injury are predictive factors for recovery. Estimates exceeded clinically important thresholds. Those who had already undergone surgery had clinically better thresholds, highlighting the assessing these measures when designing presurgical rehabilitation programs.

Predictive Utility of the Functional Movement Screen and Y-Balance Test: Current Evidence and Future Directions

Musculoskeletal injury (MSI) risk screening has gained significant attention in rehabilitation, sports, and fitness due to its ability to predict injuries and guide preventive interventions. This review analyzes the Functional Movement Screen (FMS) and the Y-Balance Test (YBT) landscape. Although these instruments are widely used because of their simplicity and ease of access, their accuracy in predicting injuries is inconsistent. Significant issues include reliance on broad scoring systems, varying contextual relevance, and neglecting individual characteristics such as age, gender, fitness levels, and past injuries. Meta-analyses reveal that the FMS and YBT overall scores often lack clinical relevance, exhibiting significant variability in sensitivity and specificity among different groups. Findings support the effectiveness of multifactorial models that consider modifiable and non-modifiable risk factors such as workload ratios, injury history, and fitness data for better prediction outcomes. Advances in machine learning (ML) and wearable technology, including inertial measurement units (IMUs) and intelligent monitoring systems, show promise by capturing dynamic and personalized high-dimensional data. Such approaches enhance our understanding of how biomechanical, physiological, and contextual injury aspects interact. This review discusses the problems of conventional movement screens, highlights the necessity for workload monitoring and personalized evaluations, and promotes the integration of technology-driven and data-centered techniques. Adopting tailored, multifactorial models could significantly improve injury prediction and prevention across varied populations. Future research should refine these models to enhance their practical use in clinical and field environments.

Case Report: Rehabilitation of a giant meniscus cyst with a mixed tear

Giant meniscus cysts combined with mixed tears are relatively uncommon in clinical practice. The primary objective of rehabilitation is to restore knee joint function and prevent cyst recurrence. In this article, we discuss a series of rehabilitation strategies implemented for a patient who experienced both a giant meniscus cyst and a mixed tear.

Effects of kinesio taping on lower limb biomechanical characteristics during dynamic postural control tasks in individuals with chronic ankle instability

PURPOSE

Previous studies have demonstrated significant biomechanical differences between individuals with chronic ankle instability (CAI) and healthy controls during the Y-balance test. This study aimed to examine the effects of kinesio taping (KT) on lower limb biomechanical characteristics during the Y-balance anterior reach task in individuals with CAI.

METHODS

A total of 30 participants were recruited, comprising 15 individuals with CAI and 15 healthy controls. All participants were randomly assigned three taping conditions: no taping (NT), placebo taping (PT), and KT, followed by the Y-balance anterior reach task. Each condition was separated by one-week intervals. Kinematic and kinetic data of the lower limbs during the movement phase were collected using the Vicon motion capture system (Vicon, T40, 200 Hz) and two Kistler force platforms (Kistler, 1000 Hz).

RESULTS

KT significantly improved the Y-balance anterior reach distance (P = 0.003) and peak ankle eversion angle (P = 0.019) compared to NT. Additionally, KT resulted in increased peak knee flexion angle (P = 0.002, P = 0.011) and peak ankle dorsiflexion angle (P <0.001, P = 0.005) relative to both NT and PT. KT also significantly reduced mediolateral center of pressure (COP) displacement (P = 0.001) and average velocity of mediolateral COP displacement (P = 0.033) in comparison to NT. Furthermore, KT decreased mediolateral center of gravity displacement (P = 0.002, P = 0.003) relative to both NT and PT.

CONCLUSION

KT significantly improved abnormal ankle posture by promoting greater ankle dorsiflexion and eversion angles. Additionally, KT reduced mediolateral COP displacement and average velocity to improve postural stability. These changes may contribute to reduced risk of ankle sprains. Therefore, KT may serve as an effective tool for managing recurrent ankle sprains in individuals with CAI.

Comparing virtual reality and balance training effects on postural strategies during ball kicking in soccer players with chronic ankle instability

The study aimed to determine if virtual reality (VR) games could enhance neuromuscular control and improve anticipatory and compensatory strategies in ball-kicking for soccer players. It was a single-blind randomized clinical trial involving 32 male soccer players with chronic ankle instability. Participants were divided into two groups: VR games and balance training. The primary outcomes measured were the amplitude and onset time of muscle activities in the peroneus longus (PL), tibialis anterior (TA), soleus (SOL), rectus femoris (RF), biceps femoris (BF), and gluteus medius (GM) in three phases: anticipatory (APA), compensatory 1 (CPA1), and compensatory 2 (CPA2). Secondary outcomes included the Y-balance test and perceived ankle instability. Evaluations were done before and after treatment. Both groups underwent 12 sessions, three times a week, each lasting 60 min. In the VR games group, there was a significant decrease in SOL muscle activity amplitude during CPA2 after treatment (P = 0.033), and the BF muscle activated earlier (P = 0.043). The balance training group showed a significant increase in GM muscle activity amplitude during APA (P = 0.037) and earlier activation of the GM muscle post-treatment (P = 0.050). Additionally, this group demonstrated significant decreases in RF activity during CPA1 and PL activity in CPA1 and CPA2 (P = 0.048, P = 0.030, and P = 0.050, respectively). Between-group comparisons indicated a significant increase in GM muscle activity amplitude during APA and a reduction during CPA1 for the balance training group compared to the VR games group (P = 0.050 and P = 0.012, respectively). Both groups showed significant reductions in perceived ankle instability (VR group: P = 0.002, balance training group: P < 0.001) and improvements on the Y-balance test (VR group: P < 0.021, balance training group: P < 0.033), although neither group showed significant improvement in the anterior direction. Overall, both VR games and balance training effectively enhanced perceived ankle stability and dynamic postural control, with neither approach showing clear superiority. Both groups exhibited improvements in muscle activation timing, though neither outperformed the other. While both interventions led to increased muscle activity amplitude during the anticipatory and compensatory phases, the balance training group achieved somewhat greater improvements. These results suggest that both VR games and balance training are effective rehabilitation approaches for chronic ankle instability, providing comparable benefits for enhancing ankle stability and neuromuscular control, without a distinct advantage of one over the other.RCT Registration: On the Iranian Registry of Clinical Trials (IRCT20230124057197N1). Registration date: 30/06/2023.

Preseason Functional Movement Screen But Not Y-Balance Test Scores Predict Musculoskeletal Injury in Elite Female Fast-Pitch Softball Athletes

CONTEXT

Functional movement screen (FMS) and Y-balance test (YBT) are used to predict the risk of musculoskeletal injuries. FMS and YBT tools in relation to injury in elite female softball athletes have not been examined.

OBJECTIVES

This study aims to (1) compare the differences in FMS, Y-Balance upper quarter (YBT-UQ), and lower quarter (YBT-LQ) scores between injured and noninjured group and (2) determine the ability of FMS and YBT scores to predict the odds of musculoskeletal injury in elite fast-pitch female softball athletes.

DESIGN

Prospective cohort study.

METHODS

Thirty-eight athletes (age = 22.9 [2.6] y, height = 170.2 [5.2] cm, mass = 65.5 [7.2] kg) completed preseason FMS and YBT assessments. Injury data were collected throughout one full season, categorized based on the location of the injury, and then recorded as a binary variable (ie, injured and noninjured groups). FMS, YBT-UQ, and YBT-LQ scores were compared between injured and noninjured groups. Binary logistic regression was used to predict the occurrence of injury among softball athletes.

RESULTS

FMS scores were significantly lower for the injured group compared with the FMS scores belonging to the noninjured group (P ≤ .001; d = 1.52). Lower FMS composite scores predicted injury (Wald(df = 1) = 6.755; odds ratio = 0.231; P = .009; 95% confidence interval, 0.076-0.697). No between-group differences existed in YBT-UQ (P = .67; d = 0.14) and YBT-LQ (P = .16; d = 0.50) composite scores between the injured and the noninjured groups. YBT-UQ (Wald(df = 1) = 2.300; odds ratio = 0.893; P = .129; 95% confidence interval, 0.772-1.033) and YBT-LQ (Wald(df = 1) = 0.145; odds ratio = 1.024; P = .703; 95% confidence interval, 0.906-1.157) were not significant predictors of injury.

CONCLUSIONS

FMS appears to be a valuable screening tool for assessing musculoskeletal injury risk in elite fast-pitch female softball athletes.

Conservative Management and Postoperative Return to Sport in Endurance Athletes with Flow Limitations in the Iliac Arteries: A Scoping Review

BACKGROUND

Flow limitations in the iliac arteries (FLIA) is a sport-related vascular condition increasingly recognised as an occupational risk for professional cyclists and other endurance athletes. Surgical reconstruction is the definitive treatment for athletes wishing to continue competition. However, less information has been published regarding conservative management options and return-to-sport (RTS) guidelines.

OBJECTIVE

Our aim was to review the existing literature on conservative treatment of FLIA, identify knowledge gaps and propose an RTS framework for athletes returning to competition.

METHODS

A comprehensive literature review was performed using the Ovid-MEDLINE, PubMed, Embase and PEDro databases for publications relevant to conservative management of FLIA. A scoping review was conducted following PRISMA-ScR guidelines. Original, peer-reviewed publications in English describing conservative or postoperative management for athletes with FLIA were included. Additional grey literature and clinical expertise were consulted to inform RTS guidelines.

RESULTS

Overall, 62 studies were included in this review. In total, 11 categories of conservative modalities were extracted and presented qualitatively in terms of the information source (discussion or results statements) and perspective of the authors (positive, negative or mixed). We have proposed RTS guidelines covering pre-operative preparation and postoperative rehabilitation based on the available literature, clinical experience, and drawing from other areas of sports medicine research.

CONCLUSION

There is insufficient literature evaluating the effectiveness of conservative management options for FLIA to establish best practices. Considering the importance of RTS for competitive athletes, we proposed practical guidelines to help with clinician and patient decision making. Future consensus should be sought for RTS best practices.

Ankle Stability and Single-Leg Balance Control in Collegiate Female Soccer Players versus Non-Soccer Players

Ankle sprains are common in female soccer players. Ankle injuries have the potential to impact balance control, which can further contribute to recurrent injuries. This study aimed to examine if female collegiate soccer players exhibited worse ankle stability and single-leg balance than female non-soccer players, and whether there was a correlation between ankle stability and single-leg balance. Eighteen female collegiate soccer players and 22 female non-soccer players participated in the study. The Cumberland Ankle Instability Tool (CAIT) was used to evaluate ankle stability. The Athletic Single Leg Stability Test (ASLST) of the Biodex Balance System was used to examine static single-leg balance, and the Y-Balance Test (YBT) was used to examine dynamic single-leg balance. Results show that 55.56% of soccer players and 9.09% of non-soccer players exhibited chronic ankle instability. The CAIT score of soccer players was significantly lower than non-soccer players (p = .031). There were no significant differences between the two groups in the ASLST and the YBT. Very low correlations were found between the CAIT score and any static or dynamic balance measures (r < .094). Female soccer players who exhibited worsened ankle stability did not exhibit compromised static or dynamic single-leg balance. Future studies should examine if soccer players have established better motor control of single-leg standing through years of training to compensate for worse ankle stability. In addition, the CAIT score alone might not accurately represent static or dynamic balance control in female collegiate soccer players.

Role of Thigh Muscle Strength and Joint Kinematics in Dynamic Stability: Implications for Y-Balance Test Performance

CONTEXT

The Y-Balance Test Lower Quarter (YBT-LQ) is a widely utilized tool for evaluating dynamic postural control, requiring a combination of mobility and strength. This study aimed to investigate the combined relationship between isometric thigh muscle strength and joint kinematics on YBT-LQ performance.

DESIGN

Cross-sectional laboratory study.

METHODS

Isometric quadriceps and hamstrings strength were measured before the YBT-LQ in 39 healthy participants (27 females and 12 males). The test was performed under 3-dimensional markerless motion capture, where joint kinematics were extracted from the maximum reach position from each direction. Three multivariable linear regression models were then used to determine the strongest combination of predictors for YBT-LQ performance.

RESULTS

Greater hamstrings strength and increased knee flexion, ankle dorsiflexion, and trunk ipsilateral-flexion joint angles explained 56.8% (P < .001) of the variance in anterior reach. Hip flexion, knee flexion, and ankle dorsiflexion angles were the strongest predictors for posteromedial reach distance, explaining 73.0% of the variance (P < .001). Last, 43.3% (P < .001) of the variance in posterolateral reach distance was predicted by hamstring strength and knee-flexion angle.

CONCLUSIONS

These results emphasize the importance of hamstring strength in YBT-LQ performance across different reach directions. Additionally, the kinematics illustrate a potential movement strategy for maximizing reach distance on the YBT-LQ in healthy individuals. Clinicians can utilize this information to guide interventions aimed at improving dynamic postural control, particularly by focusing on increasing hamstring strength and testing for impairments in specific movement patterns.

The effect of percussion and manual activation massage on explosive strength and balance in young adult males: A crossover pilot study

Background

Recently, the usage of percussive vibration machines in physiotherapy and sports has increased rapidly. Numerous manufacturers claim they can enhance physical performance. However, there is minimal peer-reviewed research on their efficacy. Therefore, this study aimed to investigate the effect of percussion massage (PM) on muscular performance, particularly explosive strength and balance. Moreover, this is the first study to evaluate the potential PM impact on balance.

Materials and methods

18 young male participants aged 20.89 ± 3.43 years with a BMI of 25.08 ± 3.95 completed three measurements with two interventions - PM by Theragun device (TG), activation massage (AM), and assessment without activation (WA). The targeted area was m. triceps surae, hamstrings, and m. quadriceps femoris of the dominant leg. Single-leg squat jump (SJ), countermovement jump (CMJ), and Y-balance tests (YBT) were performed. One-Way Repeated Measures ANOVA was utilized to analyze the data. The level significance threshold was set to p ≤ 0.05.

Results

No statistically significant difference was reported between TG, AM, and WA in the height of the squat jump and countermovement jump (p > 0.05). Furthermore, no significant changes were recorded in the YBT performance score (p > 0.05).

Conclusions

No improvement was reported in the monitored physical parameters when the PM by Theragun or manual AM was applied for 90 s right before the muscular performance. Therefore, we do not recommend the short-term stimulative application of PM and AM before athletic performance when lower limb explosive strength or balance improvements are the objective.

High-Definition Trans-Spinal Current Stimulation Improves Balance and Somatosensory Control: A Randomised, Placebo-Controlled Trial

OBJECTIVES

To investigate and compare the effects of three different high-definition (HD) non-invasive current stimulation (NICS) protocols on the spinal cord on support balance and somatosensory abilities in healthy young people.

METHODS

Fifty-eight students were enrolled in this crossover study. All participants underwent application of (i) 1.5 mA anodal high-definition trans spinal direct current stimulation (HD-tsDCS), (ii) 1.5 mA cathodal HD-tsDCS, (iii) 1.5 mA high-definition trans spinal alternating current stimulation (HD-tsACS), and (iv) sham HD-tsDCS/ACS over the eighth thoracic vertebra in a randomised order. Balance (Y Balance test), deep sensitivity (Tuning Fork Test), and superficial sensitivity (Monofilament Test) of the lower limbs were tested immediately before and after each intervention.

RESULTS

Balance ability improved significantly following anodal HD-tsDCS and HD-tsACS compared with that following sham HD-tsDCS/ACS. Similarly, deep sensitivity increased significantly with anodal HD-tsDCS and HD-tsACS compared to that with sham HD-tsDCS/ACS and cathodal HD-tsDCS. Furthermore, superficial sensitivity improved significantly following anodal HD-tsDCS compared with that after HD-tsACS and cathodal HD-tsDCS.

CONCLUSIONS

Our data show that HD-tsNICS effectively modulates the balance and somatosensory control of the lower limbs. Several diseases are associated with illness-induced changes in the spinal network in parallel with sensorimotor disabilities. Non-invasive spinal modulation may be a favourable alternative to conventional brain applications in rehabilitation. Future studies should therefore investigate these promising approaches among cohorts of patients with disabilities.

Risk Factors for Musculoskeletal Health: A Review of the Literature and Clinical Application

Context

Musculoskeletal disorders (MSKD) are currently the leading contributor to disability worldwide. Unlike other prevalent and disabling healthcare conditions such as CVD, risk factors associated with MSKD are not commonly discussed or integrated into current medical practice, rehabilitation practice or wellness programs. The primary purpose of this review is to describe the known risk factors most closely associated with MSKD. The secondary purpose is to propose a clinical model to manage MSK health aimed at maximizing the healthy pursuit of a physically active and healthy lifestyle.

Evidence acquisition

In this review the most common MSKD risk factors, with a focus on those that can be easily screened in clinical practice are presented. The importance of understanding the magnitude and number of risk factors present as well as the multidimensional nature of MSKD risk is discussed.

Results

A total of 11 MSKD risk factors were identified. Most of the risk factors are modifiable, and the evidence associated with modifiability for the most prominent risk factors is reviewed.Researchers have found that often patients are discharged from care with several known MSKD risk factors. In such instances, local pain and dysfunction are managed well, but expanding our rehabilitation care to include comprehensive risk factor management would ultimately benefit the patient and reduce healthcare costs.

Conclusion

The most common MSKD risk factors are discussed and a clinical framework to individualize intervention is proposed. Addressing key risk factors within rehabilitation may be an important step to reduce the enormous and growing burden these disorders are having on society.

Level of Evidence

5.

Measurement properties of Brief-BESTest scores from children, adolescents, and youth with visual impairments

Purpose: This study aimed to vet the measurement properties of Brief-BESTest scores in children, adolescents, and youth with visual impairment and blindness (YVI). Methods: A cross-sectional sample of YVI (N = 101) completed the Brief-BESTest, a modified version of the Y-Balance Test, the 360-degree turn test, bipedal quiet stance, and Activity-Specific Balance Confidence Scales. Thirty-seven YVI completed test-retest of the Brief-BESTest using a one-year interval. Using classical test theory, various forms of total and item-level Brief-BESTest score reliability and validity were investigated in YVI. Results: All inter-rater reliability coefficients were ≥ .80. When considering the eight items of the Brief-BESTest, 27 of the 28 possible correlations were statistically significant (p<.05). Various internal consistency and item difficulty results were strong. When taking total Brief-BESTest scores and their association with the complementary balance tasks/metrics into account, 11 of 13 associations were statistically significant (p<.05) providing strong convergent validity evidence. Being multimorbid and degree of vision significantly predicted total Brief-BESTest scores (p<.001) suggesting construct (i.e. known groups) validity. Numerous test-retest results (e.g. coefficients, limits of agreement) following the one-year interval were indicative of score stability. Conclusion: Practitioners and researchers should have confidence in, and consider adopting, the Brief-BESTest to examine multidimensional balance in YVI.

Immediate and acute effects of Kinesio taping on back muscle endurance, low back flexibility, and balance among sedentary individuals: A randomized controlled trial

INTRODUCTION

Sedentary lifestyles is linked to a reduction in back muscle strength, endurance, and balance, consequently increasing the risk of experiencing low back pain. Kinesio taping has been shown to be effective in enhancing endurance, flexibility, and balance. This study aimed to investigate the effects of Kinesio taping on measures of lumbar function in sedentary individuals.

METHOD

Forty-four sedentary young adults were randomly assigned into intervention and control groups. The intervention group received Kinesio tape to the lumbar region while the control group received health education. The Schober's test, Single-leg stance test, Y Balance Test, and Biering-Sorensen test were performed at baseline and 30 min and 24 h after the taping intervention.

RESULTS

There was a statistically significant increase in static balance (single-leg stance test) in the intervention group compared to the control group (p ≤ 0.05). In the Y Balance Test and Biering-Sorensen test, there was no significant difference between the intervention group and control group, though there was a significant increase in both groups from baseline to 24 h after taping. Though low back flexibility (Schober's test) significantly decreased in the intervention group, there was no significant difference between the two groups.

CONCLUSION

Kinesio taping can immediately improve static balance in people with sedentary behavior. The application of Kinesio tape had no impact on dynamic balance, low back flexibility, or low back muscle endurance.

Effect of 6-week BFRT combined with IASTAM therapy on international standard dancers with chronic ankle instability

Background

In sports dance events, athletes often face the risk of ankle injury and instability, which may have a negative impact on their training and athletic performance, and even hinder their rehabilitation process and increase the likelihood of re-injury.

Objective

This study aims to observe the effects of exercise intervention (low-load ankle muscle strength training with blood flow restriction training (BFRT) equipment and balance training with blood flow restriction training equipment) combined with instrumentation therapy (Instrument-assisted soft tissue mobilization, IASTM) on ankle function, joint range of motion, and strength in sports dancers with chronic ankle instability (CAI). This study aims to provide an evidence-based approach to rehabilitation for athletes by comparing the effects of combination therapy approaches to traditional ankle strength and stability training.

Methods

Forty-two subjects with ankle instability, restriction, or discomfort were selected as observation objects and randomly divided into three groups: the combined group (n = 14, blood flow restriction training combined with IASTM), the simple blood flow restriction training group (n = 15), and the conventional ankle strength and stability training group (n = 13). The intervention lasted for 6 weeks, once a week. The three groups were assessed with the Cumberland ankle instability assessment, Foot and Ankle Ability Measure (FAAM) ankle function assessment score, and ankle range of motion measurement before intervention, after the first intervention, and after 6 weeks of intervention. The ankle strength test was compared and analyzed only before and after intervention.

Result

There was no significant difference in the participant characteristics of the three intervention groups. In terms of Cumberland Ankle Instability Tool (CAIT) scores, within-group comparisons showed that the scores after the first intervention and at the 6-week mark were significantly higher than before the intervention (P < 0.05). Between-group comparisons revealed that the combined intervention group had higher CAIT scores than the other two groups after the 6-week intervention. Regarding the FAAM functional scores, all three interventions significantly improved ankle joint function in patients with chronic ankle instability (P < 0.05), with the BFRT group showing significantly higher FAAM - Activities of Daily Living scale (FAAM-ADL) scores than the control group (P < 0.05). Both the combined and BFRT groups also had significantly higher FAAM-SPORT scores after the first intervention compared to the control (P < 0.05). In terms of ankle range of motion improvement, the combined intervention group showed a significant increase in ankle joint motion after the intervention (P < 0.05), particularly in the improvement of dorsiflexion ability (P < 0.05). As for ankle strength enhancement, all three intervention groups experienced an increase in ankle strength after the intervention (P < 0.05), with the combined intervention group showing a significant improvement in both dorsiflexion and inversion strength compared to the control group (P < 0.05).

Conclusion

BFRT combined with IASTM, isolated BFRT, and conventional ankle strength and stability training significantly improve stability, functionality, and strength in CAI patients. The combined intervention demonstrates superior efficacy in improving ankle range of motion compared to isolated BFRT and conventional approaches.

Are changes in pain intensity related to changes in balance control in individuals with chronic non-specific low back pain? A systematic review and meta-analysis

PURPOSE

The aim of this study was to summarize the evidence regarding whether pain reduction in individuals with chronic non-specific low back pain (CNSLBP) following conservative interventions is related to corresponding improvements in balance control.

METHODS

Randomized controlled trials were identified from 5 databases (MEDLINE, Cochrane Library, Embase, Web of Science, and PsycINFO). Two reviewers independently screened and identified relevant studies that investigated the effects of non-surgical or non-pharmacological CNSLBP treatments on both pain intensity and balance control. Meta-regression analyses were performed to establish the associations between post-treatment changes in these 2 variables.

RESULTS

Thirty one studies involving 1280 participants with CNSLBP were included. Moderate-quality evidence suggested that pain reduction was associated with and explained 34%-45% of decreases in body sway, as measured by center-of-pressure (CoP) area and CoP velocity with eyes open. However, no significant association was observed between pain reduction and CoP area or velocity in anteroposterior/mediolateral directions. Similarly, there was no significant association between pain reduction and CoP distance or radius. Low-quality evidence indicated that pain relief explained a 15% improvement in one-leg stance with eyes open but not in the eyes-closed condition. Additionally, very low-quality evidence suggested that pain relief explained a 44% decrease in the static anteroposterior stability index with eyes closed but not in the eyes-open, mediolateral, or overall conditions. Furthermore, low-quality evidence indicated that reduced pain was associated with and accounted for 25%-43% of the improved composite and posteromedial scores of the star-excursion balance test, rather than the anterior and posterolateral scores.

CONCLUSION

Depending on the type of balance assessment, pain relief following conservative interventions may slightly to moderately enhance balance control in individuals with CNSLBP. Clinicians should pay close attention to the balance control in patients with CNSLBP, particularly among older adults.

Effect of Lower Limb Muscle Fatigue on Dynamic Balance Performance in Healthy Young Adults: Role of Arm Movement

There is evidence that balance performance deteriorates due to exercise-induced muscle fatigue. However, it is unknown if free arm movement during balance testing can compensate for, or restricted arm movement can amplify these performance degradations. Thus, the objective of this study was to compare the effects of free versus restricted arm movement on balance performance under non-fatigued and fatigued conditions. Fifty-two healthy participants (men=31, women=21; age=22.6±1.6 years) were assessed for their dynamic balance (reach distances for the Y Balance Test - Lower Quarter) under non-fatigued and fatigued (repetitive vertical bipedal box jumps until failure) conditions using two different arm positions: free (move the arms freely) and restricted (keep the arms akimbo) arm movement. Restriction of arm movement (all p< 0.001; 0.48≤ η p 2 ≤0.79) and application of fatigue ( p≤ 0.003; 0.16≤ η p 2 ≤0.28) independently, but not the interaction between the two (except for the posteromedial reach direction: p= 0.046; η p 2 =0.08) , resulted in significantly deteriorated lower limb reach distances. These findings suggest that free arm movement and thus the use of an 'upper body strategy' has no compensatory effect on muscle fatigue-induced balance deteriorations.

Evaluation of hop tests based on Y-Balance test and FMS test outcomes in volleyball and basketball players to identify those prone to injury: a potential predictor of injury

BACKGROUND

The quest for a reliable and effective method to identify athletes at risk of injury holds the promise of significantly reducing injury rates and improving overall athletic performance. This research delved into the relationship between the Functional Movement Screen (FMS), Y-Balance Test (YBT), and Hop tests (Side hop, Medial triple hop, and Lateral step-down hop), aiming to determine the potential in predicting injuries of hop tests among division 1 volleyball and basketball players.

METHODS

This research was conducted with fifty-two participants from the Division 1 league, encompassing both volleyball and basketball players. The study rigorously employed the Functional Movement Screen (FMS), the Y-Balance Test (YBT), and various hop tests (side hop test, medial triple hop test, lateral step-down hop) to measure relevant variables. The data analysis used logistic regression, ensuring a comprehensive approach to the study.

RESULTS

Results showed no significant relationship between FMS and Hop test for predicting injuries, but there was a relationship between ΔY and side hop that shows side hop test can predict injury, but there was no relationship between Lateral step down, Medial triple hop, and ΔY.

CONCLUSIONS

Based on our findings, side hop, despite the medial triple hop and lateral step-down test, can be used as a sports injury predictor.

Landing error scoring system: A scoping review about variants, reference values and differences according to sex and sport

OBJECTIVE

The Landing Error Scoring System (LESS) is a movement analysis tool proposed to identify the risk of anterior cruciate ligament injuries, very useful for injury prevention. The aim of this study is to review the variants of the LESS, their normative scores and the differences according to sex and sport practiced.

METHODS

PubMed, Scopus and ScienceDirect databases were searched from inception to October 19, 2023. Studies were eligible if the objective was finding normative or reference scores for the LESS, analyze the differences between sexes or sports, or used some variant of the test. Results were limited to available full-text articles published in English in peer-reviewed journals.

RESULTS

Of the 360 articles identified, 20 were included for a full analysis (18,093 participants, age = 8-30 years, males = 70.6%). The military population was the most frequently analyzed (7 studies, n = 16,603). Results showed six variants of the LESS and average values ranged from 2.56 to 7.1. Males and females showed different pattern landing with errors in different planes.

CONCLUSIONS

Our findings highlight the need for more field studies on LESS reference scores, particularly for females and basketball or hockey players. Further research is required before conducting a systematic review and meta-analysis.

Platform Design for Optical Screening and Conditioning for Injury Resilience

INTRODUCTION

Musculoskeletal injuries (MSKIs) among active duty soldiers result in more than 10 million limited duty days each year and account for more than 70% of the medically nondeployable population. Overuse injuries in lower limbs from running, foot marching long distances with heavy loads, and lifting heavy objects are the most common types of injuries in the military. Physical training and rehabilitation exercises for greater resiliency through aerobic, muscle strength, endurance, and agility conditioning programs can prevent or reduce the effects of MSKIs if Soldiers adhere to proper biomechanics and training techniques. We are introducing a three-dimensional (3D) camera-based platform for Optical Screening and Conditioning for Injury Resilience (OSCIR) that is designed to identify and correct high-risk movement patterns based on quantifiable biomechanical measurements in clinical or field settings. Our goal is to improve resilience to MSKI by offering greater access to quality of movement skills in warfighters through an autonomous device that can be used in Sports Medicine and Reconditioning Team (SMART) clinics and High-Intensity Tactical Training (HITT) sites.

MATERIALS AND METHODS

OSCIR fuses four pairs of Kinect Azure cameras into a concise footprint to achieve suitable sampling rates and an unobstructed field of view for accurate dynamic movement tracking using a custom point cloud solution. We designed a unique multistage 3D joint tracking algorithm architecture to methodically isolate the human body point cloud from the background, identify individual limb segments, and perform iterative joint optimization at the global and local joint levels. We evaluated the feasibility of our prototype system among N = 12 control participants (6 M/6 F; 21-37 years) in compliance with the Western Institutional Review Board (Tracking #20225920, approved on November 4, 2022). Five task-specific MSKI outcome metrics identified by end-user physical therapists and athletic trainers as indicators for movement quality were assessed across 7 lower-extremity exercises derived from standardized MSK assessment/conditioning batteries used in the military. Data were recorded concurrently by OSCIR and a reference standard Vicon motion capture system for validating system accuracy.

RESULTS

Task-specific MSKI indicators for knee flexion and hip flexion range of motion achieved an average error of 4.05 ± 2.34°, while 3D position-based postural outcomes of left-right foot distance, left-right hand distance, and step length obtained mean absolute errors of 2.58 ± 2.30 cm. Results support the feasibility of our system in achieving outcomes that are comparable to currently accepted laboratory standards.

CONCLUSIONS

Our study describes the integration process for a 3D camera-based clinical system for MSKI conditioning and rehabilitation. The impact of our system will enable key stakeholders in the military to manage MSKIs in warfighters by automating key assessment and rehabilitation test batteries; making tests more readily accessible, and interpretations more accurate by providing objective biomechanical measures. OSCIR is undergoing turn-key design features to serve as a screening tool for warfighters to readily assess susceptibility to MSKI or as a training platform to help guide exercise techniques to achieve resiliency against future injuries.

Influence of protocol variables on outcomes of the star excursion balance test group (SEBT, mSEBT, YBT-LQ) in healthy individuals: a systematic review

Background

The "SEBT group," which includes the Star Excursion Balance Test (SEBT), its modified version (mSEBT), and the Lower Quarter Y-Balance Test (YBT-LQ), is used to assess the limits of stability. Interestingly, the testing protocol allows users a considerable degree of flexibility, which can affect the obtained results. Therefore, the objective of this systematic review was to analyze the impact of different protocol variants within the "SEBT group" on outcomes.

Methods

Data were acquired by searching 4 databases (MEDLINE, ScienceDirect, Wiley, Springer Link) focusing on studies published in English in peer-reviewed journals, empirical in nature, conducted on healthy individuals, and examining the effects of various protocol variants on test outcomes. Study quality was assessed with the NHLBI quality assessment tool for pre-post studies with no control group.

Results

The calculation method based on the maximum repetition yields statistically significantly higher results compared to other calculation methods. Allowing unrestricted arm movements during the test results in statistically significantly higher scores compared to the procedure that restricts arm movements. The impact of a warm-up, wearing footwear during testing, and using a dedicated kit remains ambiguous. To obtain reliable results, 4-6 familiarization trials are necessary, though fewer may suffice for athletes experienced in performing the test.

Conclusion

This systematic review highlights the significant impact of the calculation method and arm movement restrictions on the outcomes of the "SEBT group." The effects of wearing footwear during testing, warm-up, and using a dedicated test kit remain unclear. The required number of familiarization repetitions may varies depending on biological maturity level of the person being tested. Future research should develop a warm-up protocol tailored to the needs of the "SEBT group," and investigate the impact of heel elevation during testing on outcomes.

Systematic review registration

The protocol for this systematic review was prospectively registered in the OSF Registries (https://doi.org/10.17605/OSF.IO/JSKH2).

Lower-Quarter Y-Balance Test Differs by Age: Younger Athletes May Not Be Generalized to High School-Aged Counterparts

Background

Given rising youth sport participation, 8 to 10-year-olds increasingly display comparable lower-extremity injury incidence to 11 to 17-year-olds and require effective return to sport criteria. One such criterion which quantifies dynamic stability is the Y-Balance Test (YBT), though it has not been validated in children under age 11.

Hypothesis/Purpose

The purpose of this study was to examine the performance of 8 to 10-year-old patients on the YBT after lower-extremity injury and determine how these results compare to larger samples of age-grouped athletes within the validated 11 to 17-year-old range. It was hypothesized that 8 to 10-year-olds would display different normalized YBT distances compared to 11 to 17-year-olds.

Study Design

Cross-sectional Study.

Methods

Patients (N=1093) aged 8 to 17 who presented to a pediatric sports medicine practice with a lower-extremity injury and completed the YBT between December 2015-May 2021 were included. Anterior, posteromedial, and posterolateral YBT scores were collected at return-to-sport for affected and unaffected limbs. Scores were normalized to limb length, and composite scores were created. Between-limb differences were calculated in groups of ages 8-10, 11-12, 13-14, and 15-17. Groups were also evaluated for differences by sex.

Results

A rise in performance was observed in unaffected limb anterior reach from ages 8 to 10 years to 11 to 12 years followed by a subsequent significant decrease at older ages (p<0.001). Affected limb anterior reach differed between the youngest group and two oldest groups (p=0.004). Anterior and composite difference were significantly different between the oldest three groups (p=0.014 anterior; p=0.024 composite). No differences were observed between sexes in 8 to 10-year-olds, though 11 to 12-year-old females reached further during all eight distances. In the older three groups, males generally displayed greater between-limb differences.

Conclusion

YBT scores, specifically anterior reach, demonstrated inconsistency by age and sex across a large adolescent cohort. Existing return-to-sport standards should not be used with younger athletes, and individual validation is required.

Level of Evidence

Level III.

Social jetlag affects jump skills in sub-elite volleyball players

Social jetlag (SJL), resulting from misalignment between biological rhythms and social schedules, has emerged as a prevalent phenomenon in modern society, particularly among young athletes. However, the effect of SJL on performance is poorly studied. Jump and dynamic balance are two key skills in volleyball, as the first allows the player to perform better both during the offense and defense phase, and the second is fundamental in landing and in injury prevention. Therefore, our aim was to investigate the effect of SJL on jump skill performance and balance in female volleyball players. Thirty female volleyball players (mean age: 17.3 ± 0.88 years) participated in the study. SJL was assessed using the Munich ChronoType Questionnaire (MCTQ), integrated with Jankowsky's sleep-corrected formula. Jump skill performance was evaluated using a standardized jump test, the Vertec Jump Test, while balance was assessed with the Y Balance Test. The tests were performed at 09:00 a.m. and at 06:00 p.m. The results revealed that players with greater SJL exhibited decreased jump performance, characterized by lower vertical jump height (p = 0.02). Furthermore, players with lower SJL showed the typical difference between morning and afternoon performance (p = 0.001), demonstrating their synchronization between biological rhythms and social commitments, while no statistically significant difference between the two sessions was shown in players with higher SJL. Regarding balance, no significant association with SJL was found, but the morning session yielded lower results than the afternoon one (p = 0.01). These findings highlight the detrimental impact of SJL on jump skill performance, underscoring the importance of optimizing sleep-wake schedules and circadian alignment to enhance athletic performance. Future research should explore targeted interventions, such as sleep hygiene education, to minimize social jetlag and promote optimal performance in adolescent athletes.

Adapted Training to Boost Upper Body Sensorimotor Control and Daily Living Functionality in Visually Impaired Baseball Players

Background and Objectives: Vision significantly contributes to postural control, balance, coordination, and body kinematics, thus deeply influencing everyday functionality. Sight-impaired subjects often show upper body anatomofunctional and kinetic chain alterations negatively impacting daily living efficiency and autonomy. The present study aimed to investigate and train, for the first time, upper body sensorimotor control in an Italian blind baseball team to boost global and segmental functionality while contemporarily prevent injuries. Materials and Methods: The whole team underwent a validated test battery using both quantitative traditional tools, such as goniometric active range of motion and muscular/functional tests, and an innovative biofeedback-based device, a Libra proprioceptive board. Consequently, a 6-week adapted training protocol was designed and leaded to improve sensorimotor control and, hence, counteract disability-related deficits and sport-specific overuse syndromes. Results: Statistically significant improvements were observed in all the investigated parameters. Noteworthy, an overall boost of global and segmental stability was detected through an orthostatic dynamic balance enhancement during the Y Balance test (p = 0.01) and trunk multiplanar control improvement on the Libra board (p = 0.01). Concurrently, the comparison of baseline vs. post-intervention outcomes revealed a consistent increase in upper body mobility (p < 0.05 for all the assessed districts), core recruitment (p = 0.01 for all the administered functional tests), and proprioceptive postural control (p = 0.01 for the Libra board validated test). Conclusions: Our findings suggest that a tailored sensorimotor training, conceived and led by an adapted physical activity kinesiologist, may effectively improve upper body functional prerequisites and global proprioceptive control, thus potentially promoting autonomy, quality of life, and physical activity/sport practice adherence in visually impaired individuals.

Intrinsic and extrinsic variables impacting upper quarter Y-balance test scores in sporting cohorts: A systematic review

INTRODUCTION

The upper quarter y-balance test (YBT-UQ) is a functional screening tool used to detect musculoskeletal injury risk, aid rehabilitation, and monitor dynamic function, strength and control, yet little is currently known about intrinsic and extrinsic factors that influence reach scores.

OBJECTIVES

This systematic review aimed to determine if age, sex, or interventions influenced reach scores and whether between-limb differences were common in non-injured sporting populations, with a secondary aim to identify if sport impacted YBT-UQ reach.

METHODS

Web of Science, PubMed, and SportDiscus were systematically searched from January 2012 to November 16, 2023, revealing twenty-three studies satisfying inclusion criteria of published in English between 2012 and 2023, healthy participants of any age including both males and females, athletic populations, YBT-UQ use to assess upper limb mobility/stability, report normalised reach scores, and peer-reviewed full-texts. Methodological quality was evaluated via National Institutes of Health (NIH) quality assessment tools for controlled interventions, observational cohort and cross-sectional designs, and pre-post with no control group.

RESULTS

Age, sex, sport, and fatigue were influencing factors; greater reach scores were achieved in older athletes (i.e. >18 years), males, and in a well-rested state. Between-limb differences were not common in sporting populations; therefore, asymmetries may be useful for practitioners to aid injury risk identification.

CONCLUSION

This is the first systematic review investigating YBT-UQ influencing factors and thereby provides context for clinicians regarding characteristics that impact reach scores in sporting populations, from which normative values could be determined and further aid clinical decisions or areas to improve regarding injury risk.

Effect of whole-body vibration frequency on objective physical function outcomes in healthy young adults: Randomized clinical trial

INTRODUCTION

Whole-body vibration (WBV) is used to improve muscle function but is important to know if doses can affect the objective function outcomes.

OBJECTIVE

To compare the effect of two frequencies of WBV on objective physical function outcomes in healthy young adults.

METHODS

Forty-two volunteers were randomized into three groups: sham group (SG), and WBV groups with 30 (F30) and 45 Hz (F45). A 6-week WBV intervention protocol was applied by a vibrating platform twice a week, with the platform turn-off for SG and with two frequencies according to group, 30 or 45 Hz. The objective physical functions outcomes assessed were the proprioceptive accuracy, measured by proprioceptive tests, and quasi-static and dynamic balances, measured by Sensory Organization Test (SOT) and Y Balance Test, respectively. The outcomes were assessed before and after the WBV intervention. We used in the results comparisons, by GzLM test, the deltas percentage.

RESULTS

After the intervention, no statistical differences were observed in percentage deltas for any outcomes (proprioceptive accuracy, quasi-static and dynamic balances).

CONCLUSION

Objective physical function outcomes, after the 6-week WBV protocol, did not present statistically significant results in any of the intervention groups (F30 or F45) and SG.

Return to Play Assessment After Lateral Ankle Sprains - German Male Elite Youth Football (Soccer) Academy Baseline Data

Background

Lateral ankle sprain (LAS) is one of the most common types of injury in football (soccer). Normative baseline data of performance tests for Return to Play (RTP) decision are still lacking.

Purpose

The primary aim of this study was to generate baseline values for uninjured elite youth football players for a multifactorial RTP assessment and compare with previously published data. A secondary aim was to investigate the use of the Limb Symmetry Index (LSI) as a method to determine whether an athlete passes a performance test or not.

Study Design

Observational Cohort study.

Methods

Baseline data of performance tests (Y-Balance [YBT-LQ], Heel Rise [HRT]; Singe Leg Squat [SLST]; Single Leg Drop Jump [SLDJ]; Side Hop [SHT]; Figure of 8 Hop [F-8]; Modified Agility T-Test [MAT]) were assessed in 20 elite youth football players, aged 16-21 years. Additionally, the traditional LSI (dividing the result of the non-dominant leg by the result of the dominant leg and multiplying by 100) and directionally corrected LSI (the worst value is divided by the better value and multiplied by 100) were calculated. The test values were compared to previously reported study results. LSI and side-to-side comparisons between dominant and non-dominant leg sides were analyzed using the Wilcoxon test.

Results

Male elite youth football players achieved better results in the dynamic performance tests (SHT, F-8, and MAT) compared to reference values of the cohorts previously described in the literature: YBT-LQ total score (cm) dominant (dom) 99.3±8.3, non-dominant (ND) 99.5±10.4; HRT (average number) dom. 27.1±5.4, ND 25.2±5.1); SLDJ height (cm) dom 15±5, ND 15±5 and contact time (sec) dom 0.29±0.08, ND 0.29±0.07, Reactive Strength Index (RSI) dom 0.52±0.12, ND 0.50±0.13); SHT (sec) dom 7.12±0.73, ND 7.39±0.93; F-8 (sec) dom 10.52±1.02, ND 10.37±1.04; and MAT (sec) 5.82±0.22. Directionally corrected LSI differed significantly from the traditional calculated LSI (p<0.05).

Conclusion

The findings of this study highlight the need to determine specific baseline data for RTP testing in male elite youth football players after LAS. The traditional LSI should not be used as a "stand alone method" for determining RTP. LSI calculations should consider the direction of asymmetry to determine passing a performance test or not.

Level of evidence

3b.

Effects of technological running shoes versus barefoot running on the intrinsic foot muscles, ankle mobility, and dynamic control: a novel cross-sectional research

BACKGROUND

Technological running shoes have become increasingly popular, leading to improvements in performance. However, their long-term effects on foot musculature and joint mobility have not been thoroughly studied.

OBJECTIVE

To compare the activation of the intrinsic foot muscles between runners wearing technological footwear and barefoot runners. Secondary objectives included assessing ankle dorsiflexion (DF) range of motion (ROM) and dynamic postural control in both groups.

METHODS

A cross-sectional study was conducted involving 22 technological footwear runners and 22 barefoot runners. Ultrasonography was used to measure the thickness of the plantar fascia (PF) and the quadratus plantae (QP), abductor digiti minimus (ADM), abductor hallucis (AH), and flexor hallucis longus (FHL) muscles. Ankle mobility and dynamic postural control were also recorded.

RESULTS

Ultrasonography measurements showed statistically significant differences for PF thickness (mean difference [MD]: -0.10 cm; 95% CI: -0.13, -0.05 cm), QP cross-sectional area (CSA) (MD: -0.45 cm2; 95% CI: -0.77, -0.12 cm2), ADM CSA (MD: -0.49 cm2; 95% CI: -0.70, -0.17 cm2), and FHL thickness (MD: 0.82 cm; 95% CI: 0.53, 1.09 cm), with all measurements being lower in the group wearing technological footwear compared to the barefoot runners. Ankle DF ROM was also significantly greater for the barefoot runners (MD: -5.1°; 95% CI: -8.6, -1.7°).

CONCLUSIONS

These findings suggest potential implications for the foot musculature and ankle mobility in runners using technological footwear.

Lower limb balance, ankle dorsiflexion, orofacial tissue pressure, and occlusal force of rugby players

This cross-sectional study examined the lower limb balance, ankle dorsiflexion, orofacial tissue pressure, and occlusal strength of rugby players. Twenty-six participants were divided into groups: rugby players (n ​= ​13) and healthy sedentary adults (n ​= ​13). Participants underwent an analysis of lower limb balance using a composite score (Y-Balance Test). Ankle dorsiflexion was measured using the Lunge Test. The Iowa Oral Performance Instrument was employed to measure orofacial tissue pressure. Bite force was measured with a dynamometer, and T-Scan assessed occlusal contact distribution. Data were analyzed using the t-test (p ​< ​0.05) and ANCOVA with age and weight as covariates, where it is possible to verify that these factors did not influence the results obtained. Significant differences were observed in the balance of the right (p ​= ​0.07) and left (p ​= ​0.02) lower limbs, where rugby players had lower composite scores. There were significant differences in the right (p ​= ​0.005) and left (p ​= ​0.004) lunges, with rugby players showing lower values, as well as lower tongue pressure (p ​= ​0.01) and higher lip pressure (p ​= ​0.03), with significant differences to sedentary participants. There was no significant difference in molar bite force and distribution occlusal contacts between groups. Rugby seems to reduce lower limb displacement, cause ankle hypomobility, lead to changes in orofacial tissues, particularly the tongue and lips. This study is significant for identifying significant differences between rugby players and sedentary individuals, providing new insights into the impact of rugby on health and performance, which can benefit sports training and injury prevention.

Effect of low versus high balance training complexity on balance performance in male adolescents

OBJECTIVE

The current study aimed to determine the effects of low (i.e., balance task only) versus high (i.e., balance task combined with an additional motor task like dribbling a basketball) balance training complexity (6 weeks of training consisting of 2 × 30 min balance exercises per week) on measures of static and dynamic balance in 44 healthy male adolescents (mean age: 13.3 ± 1.6 years).

RESULTS

Irrespective of balance training complexity, significant medium- to large-sized pretest to posttest improvements were detected for static (i.e., One-Legged Stance test, stance time [s], 0.001 < p ≤ 0.008) and dynamic (i.e., 3-m Beam Walking Backward test, steps [n], 0.001 < p ≤ 0.002; Y-Balance-Test-Lower-Quarter, reach distance [cm], 0.001 < p ≤ 0.003) balance performance. Further, in all but one comparison (i.e., stance time with eyes opened on foam ground) no group × test interactions were found. These results imply that balance training is effective to improve static and dynamic measures of balance in healthy male adolescents, but the effectiveness seems unaffected by the applied level of balance training complexity.

Lower extremity movement quality in professional team sport athletes: Inter-rater agreement and relationships with quantitative results from the corresponding pattern

BACKGROUND

Adequate movement control and quality can be prerequisite functions for performance of the lower extremity. The purposes of our work were 1) to explore the agreement of an efficient test battery assessing qualitative movement execution and 2) to determine its consistency with quantitative performance tests from the corresponding movement pattern.

METHODS

The participants were professional male association football players competing in the first German Bundesliga. They performed four movement quality tests (Single-limb balance squat, Balance forward hop, Balance side hop, Balance 90° rotation hop) and the corresponding performance tests (Y-balance test, Forward hop for distance, Side hop test, Square hop test). Qualitative tests were judged by two experienced raters; the ratings were compared to determine inter-rater agreement using Kappa statistics. The relationship with the quantitative tests was determined using Spearman's rank correlations.

RESULTS

Thirty participants (19 to 33 years old) were included in this study. We found an at least substantial level of agreement (Cohen's Kappa, 0.64-0.84) with an excellent percentage of exact (83-93%) agreement between the two raters for the movement quality tests. Our findings revealed that the quantitative test results are only slightly related to the movement quality outcomes (ρ(27) <|0.3| and P > 0.2).

CONCLUSIONS

Consequently, the qualitative test results provide unique information and complement corresponding quantitative performance tests in professional football athletes. Their observational judgement of foot position, lower limb alignment and upper body control in sagittal, frontal, and transverse planes is agreeable.

Study on the effect of blood flow restriction training combined with IASTAM on ankle strength and function intervention in athletes with chronic ankle instability in sport dance events

BACKGROUND

Athletes engaged in sports dance frequently encounter the potential for ankle injuries and instability, factors that may contribute to diminished training efficacy, compromised athletic performance, prolonged recuperation, and heightened susceptibility to recurring injuries.

OBJECTIVE

The objective of this study was to investigate the impact of an exercise intervention (comprising blood flow restriction training combined with low-load ankle muscle strength training and balance training) as well as instrument-assisted soft tissue mobilization (IASTM) on the foot and ankle function, strength, and range of motion in sports dance athletes exhibiting ankle instability (CAI).

METHODS

Thirty participants exhibiting ankle instability, restriction, or discomfort were recruited and randomly assigned to two groups: the Test group (comprising blood flow restriction training combined with IASTM, n = 15) and the traditional ankle strength training group (n = 15). The intervention spanned 4 weeks, with one session per week. Assessment of the Cumberland Ankle Instability Tool (CAIT), Foot and Ankle Ability Measure (FAAM), and ankle range of motion occurred at three time points: pre-intervention, immediately following the initial intervention, and after 4 weeks of intervention. Ankle strength testing was conducted solely before and after the intervention for comparative analysis.

RESULTS

There were no significant variances in baseline characteristics between the two intervention groups. In terms of CAIT scores, both groups exhibited notably higher scores following the initial intervention and after 4 weeks of intervention compared to pre-intervention (P < 0.05). The Test group displayed higher CAIT scores than the control group, signifying a more pronounced enhancement in ankle stability among patients in the Test group. Concerning FAAM scores, both groups significantly enhanced ankle function in CAI patients (P < 0.05), with the Test group demonstrating notably higher FAAM-SPORT scores than the control group (P < 0.05), indicating superior restoration of athletic capability in the Test group. As for improvements in ankle range of motion, both groups demonstrated significant enhancements compared to pre-intervention (P < 0.05). The Test group exhibited significantly superior improvements in dorsiflexion, eversion, and inversion range of motion compared to the control group (P < 0.05), while the control group did not exhibit significant enhancements in plantarflexion and eversion range of motion (P > 0.05). Both groups displayed enhanced ankle strength in CAI patients following the intervention (P < 0.05), with the Test group manifesting notably higher dorsiflexion and inversion strength than the control group (P < 0.05).

CONCLUSION

Both blood flow restriction training combined with IASTM and traditional ankle strength and stability training have shown significant improvements in stability, function, strength, and range of motion in CAI patients. Furthermore, the Test group exhibits superior efficacy in ankle stability, daily functional movement, dorsiflexion, and eversion range of motion compared to the control group.

CLINICAL TRIAL REGISTRATION

9 February 2024, ClinicalTrials.gov, ID; NCT06251414.

Direct Current Stimulation over the Primary Motor Cortex, Cerebellum, and Spinal Cord to Modulate Balance Performance: A Randomized Placebo-Controlled Trial

OBJECTIVES

Existing applications of non-invasive brain stimulation in the modulation of balance ability are focused on the primary motor cortex (M1). It is conceivable that other brain and spinal cord areas may be comparable or more promising targets in this regard. This study compares transcranial direct current stimulation (tDCS) over (i) the M1, (ii) the cerebellum, and (iii) trans-spinal direct current stimulation (tsDCS) in the modulation of balance ability.

METHODS

Forty-two sports students were randomized in this placebo-controlled study. Twenty minutes of anodal 1.5 mA t/tsDCS over (i) the M1, (ii) the cerebellum, and (iii) the spinal cord, as well as (iv) sham tDCS were applied to each subject. The Y Balance Test, Single Leg Landing Test, and Single Leg Squat Test were performed prior to and after each intervention.

RESULTS

The Y Balance Test showed significant improvement after real stimulation of each region compared to sham stimulation. While tsDCS supported the balance ability of both legs, M1 and cerebellar tDCS supported right leg stand only. No significant differences were found in the Single Leg Landing Test and the Single Leg Squat Test.

CONCLUSIONS

Our data encourage the application of DCS over the cerebellum and spinal cord (in addition to the M1 region) in supporting balance control. Future research should investigate and compare the effects of different stimulation protocols (anodal or cathodal direct current stimulation (DCS), alternating current stimulation (ACS), high-definition DCS/ACS, closed-loop ACS) over these regions in healthy people and examine the potential of these approaches in the neurorehabilitation.

Ankle dorsiflexion range of motion and hip abductor strength can predict Lower Quarter Y-Balance Test performance in healthy males

OBJECTIVES

The aim of the study was to assess whether strength and range of motion (ROM) of the hip and ankle are the factors determining performance in the Lower Quarter Y-Balance test (YBT-LQ).

DESIGN

Cross-sectional study.

PARTICIPANTS

66 healthy males (age: 25.2±6.8 years) participated in this study.

MAIN OUTCOME MEASURES

Participants underwent assessments of ankle dorsiflexion (DF) ROM, hip internal rotation (IR) ROM, external rotation (ER) ROM and isometric strength of hip abductor (ABD), extensor (EXT) and external rotators (ERS) muscles together with YBT-LQ for both legs. A forward 2-steps multiple linear regression analysis was conducted to examine the relationship between the predictor variables and the criterion variable.

RESULTS

Ankle DF ROM predicted anterior (ANT) reach (R2 = 0.49; R2 = 0.33; p < 0.001). The model with hip ABD strength and ankle DF ROM explained posteromedial (PM) reach variance for stance leg (R2 = 0.35; p < 0.001), while only hip ABD strength was included for kicking leg (R2 = 0.19; p = 0.007). The model with ankle DF ROM and hip ABD strength explained posterolateral (PL) reach for stance leg (R2 = 0.41; p < 0.001). Hip ABD was the only predictor for kicking leg PL reach (R2 = 0.15; p < 0.001). YBT-LQ composite score was explained by ankle DF ROM and hip ABD strength for both legs (R2 = 0.44; p < 0.001) and (R2 = 0.25; p = 0.002).

CONCLUSION

Hip ABD strength and ankle DF ROM can determine performance in the YBT-LQ. Strength of hip EXT, ERS as well as ROM of hip IR and ER did not predict YBT-LQ performance.

Validity and Responsiveness of a Modified Balance Error Scoring System Assessment Using a Mobile Device Application in Patients Recovering from Ankle Sprain

Background

Static balance is often impaired in patients after ankle sprains. The ability to identify static balance impairments is dependent on an effective balance assessment tool. The Sway Balance Mobile Application (SWAY App) (Sway Medical, Tulsa, OK) uses a smart phone or tablet to assess postural sway during a modified Balance Error Scoring System (mBESS) assessment and shows promise as an accessible method to quantify changes in static balance after injury.

Purpose

The primary purposes of this study were to determine the ability to differentiate between those with ankle sprain versus controls (construct validity) and ability to detect change over time (responsiveness) of a mBESS assessment using a mobile device application to evaluate static balance after an acute ankle sprain.

Study Design

Case-control study.

Methods

Twenty-two military academy Cadets with an acute ankle sprain and 20 healthy Cadets were enrolled in the study. All participants completed an assessment measuring self-reported function, ankle dorsiflexion range of motion (via the weightbearing lunge), dynamic balance, and static balance. Static balance measured with the mBESS using the SWAY App was validated against laboratory-based measures. Cadets with ankle sprains completed their assessment twice: once within two weeks of injury (baseline) and again after four weeks of rehabilitation that included balance training. Independent and paired t-tests were utilized to analyze differences over time and between groups. Effect sizes were calculated and relationships explored using Pearson's correlation coefficients.

Results

The mBESS scores measured by the SWAY App were lower in participants with acute ankle sprains than healthy Cadets (t = 3.15, p = 0.004). Injured participants improved their mBESS score measured by SWAY at four weeks following their initial assessments (t = 3.31, p = 0.004; Baseline: 74.2 +/- 16.1, 4-weeks: 82.7 +/- 9.5). The mBESS measured by the SWAY App demonstrated moderate to good correlation with a laboratory measure of static balance (r = -0.59, p \< 0.001).

Conclusion

The mBESS assessed with a mobile device application is a valid and responsive clinical tool for evaluating static balance. The tool demonstrated construct (known groups) validity detecting balance differences between a healthy and injured group, concurrent validity demonstrating moderate to good correlation with established laboratory measures, and responsiveness to changes in static balance in military Cadets during recovery from an acute ankle sprain.

Level of Evidence

Level 3.

What is the influence of biomechanical variables on the Y balance test performance in recreational runners?

BACKGROUND

Asymmetries and poor Y balance test (YBT) performance are associated with an increased risk of injuries in athletes. The aim of this study was to investigate the association between YBT performance with biomechanical variables in runners.

METHODS

The runners underwent the YBT, followed by the assessment of center of pressure, plank position, muscle strength (MS) of hip flexors, extensors, abductors, and external rotators, knee extensors, ankle dorsiflexion range of motion (ROM), Q angle, forefoot alignment, and passive hip internal rotation. Associations between variables were examined using multiple linear regression models with the Bayesian Information Criterion.

RESULTS

122 cases were analyzed. The R2 values were 0.38; 0.05; 0.06; and 0.15 for the anterior, posteromedial, posterolateral and composite directions models, respectively. The anterior reach in the YBT was associated with ankle dorsiflexion ROM [Sβ 95%IC: 0.43 (0.32-0.55)], passive hip internal rotation [Sβ 95%IC: 0.35 (0.24-0.47)], MS of the hip extensors [Sβ 95%IC: 0.19 (0.07-0.31)] and forefoot alignment [Sβ 95%IC: 0.14 (-0.25-0.02)]. The posteromedial and posterolateral reach were associated with MS of the hip flexors [Sβ 95%IC: 0.23 (0.09-0.37) and 0.24 (0.11-0.38)], respectively. The composite score was associated with MS of the hip flexors [Sβ 95%IC: 0.31 (0.18-0.45)], ankle dorsiflexion ROM [Sβ 95%IC: 0.24 (0.10-0.37)] and Q angle [Sβ 95%IC: 0.18 (0.04-0.31)].

CONCLUSION

YBT performance in different directions demonstrated specific associations with key biomechanical factors.

The Seated Trunk Control Test: Investigation of Reliability and Known-Groups Validity Using Individuals Post-Anterior Cruciate Ligament Reconstruction

CONTEXT

Decreased trunk neuromuscular control is a risk factor for both upper- and lower-extremity injuries, yet there are few reliable and valid clinical tests to identify deficits.

OBJECTIVE

The purpose of this study was to determine the reliability and known-groups validity of a novel clinical test, the seated trunk control test (STCT).

DESIGN

Cross-sectional reliability and known-groups validity study.

SETTING

Laboratory.

PARTICIPANTS

89 unique participants: 34 were 3 months postoperative anterior cruciate ligament reconstruction (ACLR) and 55 healthy controls.

METHODS

For the STCT, participants sat on a balance board with their eyes closed for three 30-second trials while investigators counted balance errors. Intraclass correlations (ICCs) were used to assess interrater reliability (N = 20) and test-retest reliability (N = 40). To assess known-groups validity, independent t tests were used to compare STCT errors at 3 months post-ACLR with healthy matched controls (N = 34/group). Area under a receiver operating characteristic curve identified an optimal cutoff for distinguishing between groups.

RESULTS

The STCT had perfect interrater reliability (ICC2,3 = 1.00) and good test-retest reliability (ICC3,3 = .79; 95% confidence interval = .61-.89). The ACLR group made significantly more errors on the STCT (mean [SD] = 15.5 [5.4]) than controls (mean [SD] = 8.2 [4.1]; P < .001, Cohen d = 1.52). The STCT's ability to distinguish between groups was excellent (area under a ROC curve = 0.86). A cutoff of 12 errors maximized sensitivity (76%) and specificity (85%).

CONCLUSIONS

The STCT is reliable between raters and across days. It also has excellent ability to distinguish between individuals with a recent ACLR and healthy matched controls, which provides initial evidence to suggest that the STCT may be clinically useful for identifying deficits in trunk neuromuscular control.

Are trunk stability and endurance determinant factors for whole-body dynamic balance in physically active young males? A multidimensional analysis

OBJECTIVES

Determine if (a) a better trunk stability and endurance are associated with an improved whole-body dynamic balance, and if (b) the assessment tests can be interchanged within each capability.

METHODS

Sixty-three physically active young males performed three trunk stability (i.e., the lumbopelvic stability, the unstable sitting and the sudden loading sitting tests), three trunk muscle endurance (i.e., the Biering-Sørensen, the side bridge and the front bridge tests) and four whole-body dynamic balance (i.e., the tandem and the single-leg stance, the Y-Balance, and the single-leg triple hop tests) tests two times. After assessing the reliability of the variables, a Pearson correlation analysis was performed.

RESULTS

The correlations between trunk stability and endurance tests with dynamic balance tests were non-significant except for the unstable sitting test with both the tandem (r = 0.502) and the single-leg stance (r = 0.522) tests. Moreover, no relationships were observed between the trunk stability and the trunk muscle endurance tests. Interestingly, no relationships were found between most tests within each capability (i.e., trunk stability, trunk endurance, and dynamic balance) except: (i) the front bridge stability test and the back (r = 0.461) and the side (r = 0.499) bridge stability tests; (ii) the two side bridge endurance tests (r = 0.786); (iii) the tandem and the single-leg stance tests (0.439 ≤ r ≤ 0.463); (iv) the Y-Balance and the single-leg triple hop tests (0.446 ≤ r ≤ 0.477).

CONCLUSION

Better trunk function does not seem to be a relevant factor for dynamic balance in young active males. In this population, specific measures are needed as the test interchangeability is questioned.

Randomized controlled trial study of intelligent rehabilitation training system for functional ankle instability

To investigate the intervention effect of an intelligent rehabilitation training system on patients with functional ankle instability (FAI) and to advance the research to optimise the effect of FAI rehabilitation training. Thirty-four FAI patients who participated in this trial in Guilin City from April 2023 to June 2023 were recruited as research subjects, and all subjects were randomly divided into the control group (n = 17) and the observation group (n = 17). Both groups received the conventional rehabilitation training intervention for 6 weeks, and the observation group received the additional training using the intelligent rehabilitation training system training invented by our team. Visual analogue scale (VAS), ankle active mobility, ankle muscle strength and Y-balance test (YBT) were assessed before and after treatment. Two-way repeated measures ANOVA shows that the interaction effect between time and group of VAS scores was significant (F = 35.644, P < 0.05). The interaction effect between time and group of plantar flexion mobility was significant (F = 23.948, P < 0.05), the interaction effect between time and group of dorsiflexion mobility was significant (F = 6.570, P < 0.05), the interaction effect between time and group of inversion mobility was significant (F = 8.360, P < 0.05), the interaction effect between time and group of eversion mobility was significant (F = 10.113, P < 0.05). The interaction effect between time and group of inversion muscle strength was significant (F = 18.107, P < 0.05). The interaction effect between time and group of YBT scores was significant (F = 33.324, P < 0.05). The Intelligent Rehabilitation Training System can effectively reduce pain in FAI patients, improve joint range of motion, increase inversion strength, and improve dynamic balance of the affected limb.

The effectiveness of the STOP-X training program on the knee valgus angle and balance in female basketball players with dynamic knee valgus: a randomized controlled trial

BACKGROUND

Dynamic knee valgus (DKV) accompanied by poor balance is the cause of anterior cruciate ligament (ACL) injury in athletes, and the identification and correction of these factors are always of interest to researchers. Therefore, the purpose of this research was to investigate the effect of the STOP-X program on the knee valgus angle and static and dynamic balance in female basketball players with DKV defects.

METHODS

The present study was a quasi-experimental study. Thirty female basketball players with DKV defects were purposefully identified by the single-leg landing (SLL) test and were randomly assigned to two control (n = 15) and experimental (n = 15) groups. Static balance status was evaluated with the BASS STICK test, and dynamic balance status was evaluated with the Y-balance test (YBT). The experimental group performed the STOP-X program for 25-40 min for eight weeks (three times per week), and the control group performed their traditional warm-up program. Data were analyzed by means of 2 × 2 repeated measures ANOVA followed by post hoc comparison (Bonferroni) at the significance level of (P < 0.05) with SPSS version 26.

RESULTS

The results showed that with the use of the STOP-X program, there was a significant difference between the experimental and control groups in variables of the static balance (F = 56.45; P = 0.001; ES = 0.66, PC=↑59.64%), total dynamic balance score (F = 107.57; P = 0.001; ES=↑0.79, PC=↑19.84%), and knee valgus angle (F = 119.46; P = 0.001; ES = 0.81, PC=↓34.36%).

CONCLUSION

In addition to reducing the knee valgus angle, applying the STOP-X injury prevention program can improve static and dynamic balance in female basketball players with DKV defects. Therefore, it can be recommended that sports trainers benefit from these advantages by adding STOP-X training to routine basketball exercises.

Using clinician-oriented and laboratory-oriented assessments to study dynamic stability of individuals with chronic ankle instability

To compare the dynamic stability of lower extremities between Copers and individuals with chronic ankle instability (CAI) using clinician-oriented assessments (Y-balance test, YBT) and laboratory-oriented assessments (time to stabilization, TTS). 90 participants (Copers, 45; CAIs, 45) were recruited and measured by YBT and TTS to evaluate dynamic stability. The difference of dynamic stability between Copers and CAIs was examined using a two-factor MANOVA. Only for females in anterior direction, YBT scores for the AS side of Copers were significantly higher than that of CAIs. For males, the TTS of CAIs was significantly shorter than that of Copers in the anterior, lateral, and medial direction separately. For females, the TTS of CAIs is also significantly shorter than that of Copers in the anterior, lateral, and medial direction separately. There are opposite results when evaluating the dynamic stability difference between Copers and CAIs using YBT and TTS.

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.