Dynamic postural stability differences between male and female players with and without ankle sprain

The influence of jump-landing direction on dynamic postural stability following anterior cruciate ligament reconstruction

BACKGROUND

Traditional testing prior to return to sport following anterior cruciate ligament reconstruction typically involves jump-landing tasks in the forward direction. As injury is most likely the result of multiplanar neuromuscular control deficits, assessment of dynamic postural stability using landing tasks that require multiplanar stabilization may be more appropriate. The purpose of this study was to examine how dynamic postural stability is affected when performing jump-landing tasks in three different directions.

METHODS

Fifteen athletes [11 females (18.0 ± 3.0 years) and 4 males (18.5 ± 3.1 years)] following anterior cruciate ligament reconstruction performed a series of single-limb jump-landing tasks in 3 directions. Individual directional stability indices and a composite dynamic postural stability index were calculated using ground reaction force data and were compared using separate one-way repeated measures ANOVAs.

FINDINGS

All directional stability indices demonstrated a significant main effect for jump-landing direction (medial-lateral P < 0.001, η2p = 0.95; anterior-posterior P < 0.001, η2p = 0.97; vertical P = 0.021, η2p = 0.24). The diagonal jump-landing direction produced increased medial-lateral stability and vertical stability scores, while the forward and diagonal jump-landing directions produced increased anterior-posterior stability scores. There was no significant effect for the composite dynamic stability index score.

INTERPRETATION

Jump-landing direction affects dynamic postural stability in all 3 planes of movement in athletes following anterior cruciate ligament reconstruction. Results indicate the potential need to incorporate multiple jump-landing directions to better assess dynamic postural stability prior to return to sport.

Effects of non-extensible lumbar belts on static and dynamic postural stability

BACKGROUND

Previous studies have found that increased intra-abdominal pressure helps to reduce spinal loading and improve spine stability. Non-extensible lumbar belts (NEBs) could elevate intra-abdominal pressure and augment spinal stability. NEBs have been used in the healthcare field to help reduce pain and improve spine function for people with low back pain. However, the effect of NEBs on static and dynamic postural stability is not clear.

METHODS

This study aimed to investigate whether NEBs affect static and dynamic postural stability. Twenty-eight healthy male subjects were recruited to finish four static postural stability tasks and two dynamic postural stability tests. Center of pressure (COP) values during 30 s of quiet standing, dynamic postural stability index (DPSI) and Y balance test (YBT) score with and without NEBs were analyzed.

RESULTS

NEBs had no significant effect in all COP variables in the static postural tasks. The results of a repeated measure two-way ANOVA indicated the NEBs significantly improved the dynamic postural stability in YBT score and DPSI (F _(1,27) = 5.506, p = .027, [Formula: see text] and F _(1,27) = 83.94, p = .000, [Formula: see text] respectively).

CONCLUSIONS

The study results indicate that non-extensible belts improve dynamic stability in healthy male participants, with potential implications for rehabilitation and performance enhancement programs.

ANALYSIS OF THE ARTICULAR LOAD ON THE LOWER LIMBS DURING BACKFLIP

ABSTRACT Introduction: Sports injuries restrict the acquisition of optimal results and represent a great threat to the athlete's physical health, lower limb injuries being the most prominent, mainly those caused by landing. Objective: Use biomechanics to analyze the joint load of the lower limbs during the landing process in the gymnastics backflip, establishing movement control and reducing the risk of lower limb injury. Methods: The male athletes of the National Gymnastics Team were selected as the research objects, and the three-dimensional backflip (BS) motion trajectory was completed after the landing process was completed, the vertical ground reaction force (VGRF) after landing and the lower limb muscle electromyography (EMG) after landing was collected, and the human multi-body system model and the landing platform model of the landing action were completed with the help of the system simulation software. Results: Statistics show that gymnasts train more intensively during competition or daily training, performing more than 200 landings per week, a factor that increases the risk of injuries during the backflip in athletes. Conclusion: The lower limb joint load of the landing action in gymnastics backflip is high, which will cause a certain risk of injury, and specific measures can be taken to control it. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

The Influence of Gender and the Specificity of Sports Activities on the Performance of Body Balance for Students of the Faculty of Physical Education and Sports

A sense of balance is required in sports activities, conditioning the quality of movements and physical performance. (1) The purpose of the study is to investigate the influence of gender and the specificity of sports activities on body balance. The investigated participants are 157 students of the Faculty of Physical Education and Sports/Bachelor’s degree: 109 men (age = 20.49 ± 2.03, body mass index, BMI = 22.96 ± 3.20), and 48 women (age = 20.21 ± 1.51, BMI = 21.05 ± 2.78). (2) Design: Cross-sectional study, with the definition of the variables gender and sport activity with three stages (non-athletes/NA, team sports games/TSG, and individual sports/IS). The evaluation was based on four dynamic balance tests (Bass test/points, Functional reach test/cm, Fukuda test/degrees of rotation, and Walk and turn field sobriety test/errors) and three static balance tests (Flamingo test/falls, Stork test, and One-leg standing test with eyes closed/s). (3) Results: The variance analysis (multivariate and univariate tests) indicates the superiority of women in most tests applied, but with significantly better values (p < 0.05) only for the Flamingo test and Bass test. Men have superior results only for vestibular stability (Fukuda test) and One-leg standing test, but it is statistically insignificant (p > 0.05). The TSG group has slightly better values than the IS group for the whole set of tests conducted, but these are not statistically significant (p > 0.05), so we cannot highlight the certain superiority of TSG practitioners over those involved in IS. Both the TSG and the IS group outperformed all tests compared to the NA group, with significant differences (p < 0.05), especially for the TSG. Conclusion: Women have better values than men on most tests, and performance sports students have higher average scores than those in the NA group, which demonstrates the beneficial influence of specific training on static and dynamic postural stability.

Investigating the landing kinetics factors and preparatory knee muscle activation in female handball players with and without dynamic knee valgus while performing single leg landing

Study aim: to examine the differences in landing kinetics factors (LKF) to assess the whole body stability and preparatory muscle activation (PMA) in female handball players with and without dynamic knee valgus.

Material and methods: Twenty-four professional female handball players (11 with (DKV) and 13 without (Control) dynamic knee valgus) were asked to perform three trials of a single-leg landing. LKF and surface EMG were recorded. Initial contact knee valgus angle (IC KVA), vertical ground reaction force (vGRF), confidence ellipse area of center of pressure (CEA), time to stability (TTS) and EMG from 100 ms prior to ground contact were used in the data analyses.

Results: Multivariate analyzing of LKF showed significant differences between two groups (p = 0.001) while for PMA the result was not significant (p = 0.361).

Conclusion: Altered landing mechanism considered as a predictor of non-contact knee injuries such as ACL rupture. Therefore according to current study it seems important to focus on reducing valgus angle in designing injury prevention program.

Ankle Stability and Movement Coordination Impairments: Lateral Ankle Ligament Sprains Revision 2021

This revised clinical practice guideline (CPG) addresses the distinct but related lower extremity impairments of those with a first-time lateral ankle sprain (LAS) and those with chronic ankle instability (CAI). Depending on many factors, impairments may continue following injury. While most individuals experience resolution of symptoms, complaints of instability may continue and are defined as CAI. The aims of the revision were to provide a concise summary of the contemporary evidence since publication of the original guideline and to develop new recommendations or revise previously published recommendations to support evidence-based practice. J Orthop Sports Phys Ther 2021;51(4):CPG1-CPG80. doi:10.2519/jospt.2021.0302.

The effect of foot type, body length and mass on postural stability

BACKGROUND

Poor postural stability is associated with chronic ankle instability. Previous research showed an effect of foot type on postural stability. However, the specific effect of supinated feet remains unclear.

RESEARCH QUESTION

Our study aimed to assess the effect of foot type on postural stability, while taking potential confounding effects of body mass and body height into account.

METHODS

Forty-three healthy participants between 18 and 40 years old performed barefooted single leg stance tests with eyes open (EO) and closed (EC) on solid ground, and on a balance board (BB). Foot type was determined from pressure recordings during gait, using the arch index. Ground reaction forces were measured using a force plate. Outcome measures were Center of Pressure Velocity (COPV) divided by body height, and the Horizontal Ground Reaction Force (HGRF) divided by body mass. Generalized Estimating Equations models assessed the differences between supinated, normal and pronated feet during EO, EC and on a BB.

RESULTS

During EO an interaction between supinated feet and body mass showed an increase of COPV with 0.03 × 10^-2 1/s per kilogram of mass relative to normal feet (p = .03). During EC this interaction was more pronounced with 0.22 × 10^-2 1/s increase per kilogram mass (p < .01). The HGRF did not differ between foot types in any of the conditions.

SIGNIFICANCE

Supinated feet have a larger increase in COPV compared to normal feet with increasing mass when standing on solid ground during EO and EC. This indicates that people with supinated feet and a higher mass are less stable during single leg stance.

LEVEL OF EVIDENCE

Level 3, associative study.

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

OBJECTIVE

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

DESIGN

Systematic review and narrative synthesis.

DATA SOURCES

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

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

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

RESULTS

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

CONCLUSION

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

The assessment of single-leg drop jump landing performance by means of ground reaction forces: A methodological study

BACKGROUND

Time to stabilization (TTS) and dynamic postural stability index (DPSI) are outcome measures based on ground reaction force (GRF) that are often used to quantify dynamic postural stability performance following a drop jump landing. However, their interrelations, as well as the overlap with other dynamic measures and static single-leg postural sway, are unknown.

RESEARCH QUESTION

What is the relation among TTS and DPSI, how are they related to impact forces and dynamic postural sway, and how are all these dynamic measures related to static postural sway?

METHODS

A sample of 190 elite soccer players performed four single-leg drop jump landings. TTS in three directions (vertical, anteroposterior, and mediolateral), and DPSI were intercorrelated (Pearson's r), and related to impact forces and the magnitude of horizontal GRF (HGRF) from 0.4 to 2.4 s and 3.0-5.0 s following landing. All these measures were also correlated to HGRF in the static phase (i.e., 5.3-11.7 s).

RESULTS

The TTS measures were significantly interrelated (r = 0.28-0.53), but were not significantly correlated to DPSI. TTS was more strongly related to HGRF0.4-2.4 s (r = 0.54-0.75) than to HGRF3.0-5.0 s (r = 0.32-0.54) or impact forces (r=-0.28-0.36). Vertical TTS was not significantly related to impact forces. The DPSI was most strongly related to the vertical peak force (r = 0.85), and was not significantly related to HGRF of the dynamic periods. Furthermore, TTS and dynamic HGRF were significantly related to static HGRF (r = 0.34-0.80), while DPSI and impact forces were not.

SIGNIFICANCE

TTS and DPSI do not represent similar aspects of single-leg jump landing performance. The ability to stabilize posture seems to be represented by TTS and dynamic postural sway, which partly overlaps with static postural sway. In contrast, DPSI and vertical peak force mainly reflect the kinetic energy absorption during impact. The findings can help to better understand the meaning of the outcome measures, and to translate results to rehabilitation or prevention programs.

Reliability, discriminant validity and sex comparisons of dynamic postural stability during a landing task designed to challenge transverse plane knee stability

Internal and external rotational knee stability is essential for sports performance and excessive rotation can lead to injury but is rarely assessed in injury risk analysis. The objectives of this study were to determine the between-session reliability, discriminant validity and potential sex differences of a dynamic postural stability (DPS) assessment that challenges transverse plane knee stability. Thirty-six individuals (21.7 ± 2.6 years) including 19 females (20.8 ± 1.3 years) and 17 males (22.6 ± 3.4 years) participated. We measured DPS during rotational jump tasks (RJT) over 2 test sessions utilising a force plate. Kinematic (motion analysis) and electromyographic measures were compared to a traditional anterior-posterior jump task (APJT) to assess the discriminant validity and comparisons were performed between sexes. The intraclass correlation coefficients were between 0.67 and 0.86. Significant differences in transverse rotation angle at initial contact transverse rotational velocity of the knee were observed between the 2 different RJT and between the RJT and the traditional APJT. No sex differences were observed. The new assessment had good between-session reliability and offers a different challenge than a traditional jump task. This RJT may offer a novel assessment of knee joint rotational stability in conjunction with traditional measures.

Do lower limb previous injuries affect balance performance? An observational study in volleyball players

OBJECTIVES

To study static and dynamic postural balance control in elite and sub-elite male volleyball players with or without a history of musculoskeletal lower limb injuries.

DESIGN

Cross-sectional study.

SETTING

Laboratory.

PARTICIPANTS

Data were obtained from 45 male volleyball players, divided into healthy (CON, n = 28) and previously injured (INJ, n = 17) players by means of an injury self-reported questionnaire.

MAIN OUTCOMES MEASURE

Static postural balance parameters were recorded carrying out a monopodalic test with the dominant leg on a stabilometric platform. Dynamic postural balance was assessed with the modified Star Excursion Balance Test (mSEBT) in its version based on three directions (anterior, postero-lateral and postero-medial).

RESULTS

No statistically significant differences were detected between CON and INJ for all the static postural balance parameters considered. Conversely, the mSEBT results underlined a statistically significant decrease of the performance in the three directions (P < .001) for INJ with respect to CON.

CONCLUSIONS

The mSEBT should be employed in male volleyball players with a history of musculoskeletal lower limb injuries to better assess postural balance control alterations. Moreover, the decrement of the dynamic balance performance may indicate that, before returning to competitions, the rehabilitation protocol should be more focused on dynamic balance exercises.

Dynamic postural stability, is associated with competitive level, in youth league soccer players

OBJECTIVES

To assess the effect of competitive level on dynamic postural stability in young elite and sub-elite soccer players.

DESIGN

Cross-sectional study.

SETTING

Laboratory.

PARTICIPANTS

Fifty-four male soccer players of Under 16 and Under 17 categories (mean age 15.9 ± 0.6), divided into two groups who regularly compete at national (n = 28) and regional (n = 26) levels.

MAIN OUTCOME MEASURES

Dynamic Postural Stability Index (DPSI) and vertical Time to Stabilization (vTTS) for a forward-jump landing. Static postural sway was calculated on the basis of center-of-pressure trajectories for a 20 s one-legged stance.

RESULTS

Players at national level exhibit better dynamic postural control than those at regional level, as indicated by the significantly lower DPSI (0.327 vs. 0.373, p < 0.001) and vTTS (0.887 vs. 1.158 s, p = 0.003). In contrast, no differences between groups were found in any of the postural sway parameters for the static test.

CONCLUSIONS

Young soccer players at national level are characterized by better balance performance in terms of faster and more efficient stabilization after a forward jump, while one-leg static standing tests appear not challenging enough to reveal differences in balance abilities associated with the combination of superior technical and physical features.

Postural stability deficit could predict ankle sprains: a systematic review

PURPOSE

To perform a systematic review aimed to determine (1) if the postural stability deficit represents a risk factor for ankle sprains; (2) the most effective postural stability evaluation to predict ankle sprains and (3) eventual confounding factors that could influence postural stability and ankle sprain risk.

METHODS

A systematic electronic search was performed in MEDLINE, EMBASE and CINAHL using the search terms (balance) OR (postural stability) matched with (lower limb) OR (ankle) OR (foot) and (sprain) OR (injury) on October 2 2017. All prospective studies that evaluated postural stability as risk factor for ankle sprains were included. The PRISMA Checklist guided the reporting and data abstraction. Methodological quality of all included papers was carefully assessed.

RESULTS

Fifteen studies were included, evaluating 2860 individuals. Various assessment tools or instruments were used to assess postural stability. The injury incidence ranged from 10 to 34%. Postural stability deficit was recognized as risk factor for ankle sprain (OR = 1.22-10.2) in 9 cases [3 out of 3 with Star Excursion Balance Test (SEBT)]. Among the six studies that measured the center-of-gravity sway, five were able to detect worse postural stability in athletes that sustained an ankle sprain. In nine cases, the measurement of postural stability did not show any statistical relationship with ankle sprains (four out of five with examiner evaluation). In the studies that excluded patients with history of ankle sprain, postural stability was reported to be a significant risk factor in five out of six studies.

CONCLUSIONS

The ultimate role of postural stability as risk factor for ankle sprains was not defined, due to the high heterogeneity of results, patient's populations, sports and methods of postural stability evaluation. Regarding assessment instruments, measurement of center-of-gravity sway could detect athletes at risk, however, standardized tools and protocols are needed to confirm this finding. The SEBT could be considered a promising tool that needs further investigation in wider samples. History of ankle sprains is an important confounding factor, since it was itself a source of postural stability impairment and a risk factor for ankle sprains. These information could guide clinicians in developing screening programs and design further prospective cohort studies comparing different evaluation tools.

LEVEL OF EVIDENCE

I (systematic review of prospective prognostic studies).

Time series of ground reaction forces following a single leg drop jump landing in elite youth soccer players consist of four distinct phases

The single leg drop jump landing test may assess dynamic and static balance abilities in different phases of the landing. However objective definitions of different phases following landing and associated reliability are lacking. Therefore, we determined the existence of possible distinct phases of single leg drop jump landing on a force plate in 82 elite youth soccer players. Three outcome measures were calculated over moving windows of five sizes: center of pressure (COP) speed, COP sway and horizontal ground reaction force (GRF). Per outcome measure, a Factor Analysis was employed with all windows as input variables. It showed that four factors (patterns of variance) largely (>75%) explained the variance across subjects/trials along the 12s time series. Each factor was highly associated with a distinct phase of the time series signal: dynamic (0.4-2.7s), late dynamic (2.5-5.0s), static 1 (5.0-8.3s) and static 2 (8.1-11.7s). Intra-class correlations (ICC) between trials were lower for the dynamic phases (0.45-0.68) than for the static phases (0.60-0.86). The COP speed showed higher ICC's (0.63-0.86) than COP sway (0.45-0.61) and GRF (0.57-0.71) for all four phases. In conclusion, following a drop jump landing unique information is available in four distinct phases. The COP speed is most reliable, with higher reliability in the static phases compared to the dynamic phases. Future studies should assess the sensitivity of information from dynamic, late dynamic and static phases.