Postural Control Tests Research Articles

Does Acute Exercise Stress Affect Postural Stability and Cognitive Function in Subjects with Chronic Ankle Instability?

Altered postural control in people with chronic ankle instability (CAI) may be attributed to deficits that are associated with neurocognitive function. Acute training is another factor that may negatively affect postural control and increase the risk of ankle sprain. The purpose of this investigation was to determine the effect of acute exercise on postural stability and cognitive function among patients with CAI. Fifteen patients with CAI (aged 21.5 ± 2.0 years) and 15 healthy controls (aged 20.3 ± 1.7 years) completed a single-limb stance postural control test and a battery of computer-based cognitive tests before and after acute exercise. The overall stability index (OSI) was used as a measure of postural stability. The cognitive domains tested were global cognitive score, executive function, attention, visual-spatial perception, information processing, and fine motor control. Subjects in both groups had similar OSI scores, with a trend for reduced stability in the CAI after the exercise protocol (p = 0.053). There were no differences between the groups in all cognitive domains before or after exercise. Following exercise, the domains of overall cognitive score, visual-spatial perception, and information processing speed improved in both groups (p = 0.003, p = 0.033, p = 0.001; respectively). These findings should be considered with caution due to the heterogeneity of the CAI population.

Dizziness, Psychosocial Function, and Postural Stability Following Sport-Related Concussion.

To examine if self-reported dizziness is associated with concussion symptoms, depression and/or anxiety symptoms, or gait performance within 2 weeks of postconcussion. Cross-sectional study. Research laboratory. Participants were diagnosed with a concussion within 14 days of initial testing (N = 40). Participants were divided into 2 groups based on their Dizziness Handicap Inventory (DHI) score: 36 to 100 = moderate/severe dizziness and 0 to 35 = mild/no dizziness. Participants were tested on a single occasion and completed the DHI, hospital anxiety and depression scale (HADS), Patient Health Questionnaire-9 (PHQ-9), and Post-Concussion Symptom Inventory (PCSI). Three different postural control tests were use: modified Balance Error Scoring System, single-/dual-task tandem gait, and a single-/dual-task instrumented steady-state gait analysis. Comparison of patient-reported outcomes and postural control outcomes between moderate/severe (DHI ≥ 36) and mild/no (DHI < 36) dizziness groups. Participants with moderate/severe dizziness (n = 19; age = 17.1 ± 2.4 years; 63% female) reported significantly higher symptom burden (PSCI: 43.0 ± 20.6 vs 22.8 ± 15.7; P = 0.001) and had higher median HADS anxiety (6 vs 2; P < 0.001) and depression (6 vs 1; P = 0.001) symptom severity than those with no/minimal dizziness (n = 21; age = 16.5 ± 1.9; 38% female). During steady-state gait, moderate/severe dizziness group walked with significantly slower single-task cadence (mean difference = 4.8 steps/minute; 95% confidence interval = 0.8, 8.8; P = 0.02) and dual-task cadence (mean difference = 7.4 steps/minute; 95% confidence interval = 0.7, 14.0; P = 0.04) than no/mild dizziness group. Participants who reported moderate/severe dizziness reported higher concussion symptom burden, higher anxiety scores, and higher depression scores than those with no/mild dizziness. Cadence during gait was also associated with the level of dizziness reported.

Added body mass alters plantar shear stresses, postural control, and gait kinetics: Implications for obesity

Obesity is a growing global health concern. The increased body mass and altered mass distribution associated with obesity may be related to increases in plantar shear that putatively leads to physical functional deficits. Therefore, measurement of plantar shear may provide unique insights on the effects of body mass and body distribution on physical function or performance. 1) To investigate the effects of body mass and distribution on plantar shear. 2) To examine how altered plantar shear influences postural control and gait kinetics. 1) a weighted vest forward distributed (FV) would shift the center of pressure (CoP) location forward during standing compared with a weighted vest evenly distributed (EV), 2) FV would increase plantar shear spreading forces more than EV during standing, 3) FV would increase postural sway during standing while EV would not, and 4) FV would elicit greater compensatory changes during walking than EV. Twenty healthy young males participated in four different tests: 1) static test (for measuring plantar shear and CoP location without acceleration, 2) bilateral-foot standing postural control test, 3) single-foot standing postural test, and 4) walking test. All tests were executed in three different weight conditions: 1) unweighted (NV), 2) EV with 20% added body mass, and 3) FV, also with 20% added body mass. Plantar shear stresses were measured using a pressure/shear device, and several shear and postural control metrics were extracted. Repeated measures ANOVAs with Holms post hoc test were used to compare each metric among the three conditions (α = 0.05). FV and EV increased both AP and ML plantar shear forces compared to NV. FV shifted CoP forward in single-foot trials. FV and EV showed decreased CoP range and velocity and increased Time-to-Boundary (TTB) during postural control compared to NV. EV and FV showed increased breaking impulse and propulsive impulse compared to NV. In addition, EV showed even greater impulses than FV. While EV increased ML plantar shear spreading force, FV increased AP plantar shear spreading force during walking. Added body mass increases plantar shear spreading forces. Body mass distribution had greater effects during dynamic tasks. In addition, healthy young individuals seem to quickly adapt to external stimuli to control postural stability. However, as this is a first step study, follow-up studies are necessary to further support the clinical role of plantar shear in other populations such as elderly and individuals with obesity or diabetes.

RELIABILITY OF CENTER OF PRESSURE-BASED MEASURES DURING DUAL-TASK POSTURAL CONTROL TESTING IN A YOUTH POPULATION.

Dual-task assessments can identify changes in postural control during recovery from a concussion. However, developing postural control in children presents a challenge when using adult balance assessments to examine children. The purpose of this study was to investigate the reliability of a cognitive dual-task postural control testing protocol among a youth sample with no history of concussion or exposure to head impacts. Reliability pilot study. Testing comprised nine 120 second trials of standing on a force plate collecting data at 250 Hz. Test conditions included no dual-task, counting backwards by 2, counting backwards by 3, listening, and the Stroop test. Subjects completed each test with open and closed eyes, except for the Stroop test. The force plate was used to measure the subjects' center of pressure (COP) trajectory. Nine healthy, youth subjects (average age: 11.6 ± 0.5 years) with no history of concussion or exposure to head impacts participated. Reliability was good (>0.6) or excellent (>0.75) for COP speed, sway, and sample entropy measures for several test conditions. The eyes open, no task condition produced the lowest COP measures. No differences were observed between the other dual-task conditions. Given its high measures of reliability, this dual-task protocol might be able to detect postural control changes in concussed youth athletes. 2.

Partial sleep restriction impairs static postural control in elite judo athletes

ABSTRACT The present study evaluates the effect of partial sleep restriction on postural control in judokas. Fourteen elite-level judokas performed three static postural control tests (the Unilateral Stance (US, on the Right and Left Foot); the modified Clinical Test for the Sensory Interaction on Balance (mCTSIB, on a firm and an unstable surface) stance with the eyes opened and then closed, and the Weight-Bearing Squat test (WBS)) after (i) a reference-normal-sleep-night (RN) and (ii) 4-h of partial sleep restriction at the end (SREN) (i.e., sleep from 22h30 to 03h00) or the beginning (SRBN) (i.e., sleep from 03:00h to 07:00h) of the night. Concerning US, sway velocity increased significantly after SRBN and SREN, in comparison with RN (p < 0.001) and was significantly higher in closed vs. open eyes during SRBN, SREN and RN (p < 0.001). For mCTSIB, sway velocity increased significantly during SBND and SRBN, compared to RN (p < 0.001) and was higher with eyes open than eyes closed in the foam surface during SRBN, SREN and RN (p < 0.0001). For WBS, there were no significant between conditions differences. In conclusion, partial sleep restriction of 4-h may negatively affect the postural control of judokas.

The Effect of Plantar Massage on Static Postural Control in Patients With Chronic Ankle Instability: A Critically Appraised Topic.

Clinical Scenario: Patients with chronic ankle instability (CAI) demonstrate deficits in both sensory and motor function, which can be objectively evaluated through static postural control testing. One intervention that has been suggested to improve somatosensation and, in turn, static postural control is plantar massage. Clinical Question: Does plantar massage improve static postural control during single-limb stance in patients with CAI relative to baseline? Summary of Key Findings: A search was performed for articles exploring the effect of plantar massage on static postural control in individuals with CAI. Three articles were included in this critically appraised topic including 1 randomized controlled trial and 2 crossover studies. All studies supported the use of plantar massage to improve static postural control in patients with CAI. Clinical Bottom Line: There is currently good-quality and consistent evidence that supports the use of plantar massage as an intervention that targets the somatosensory system to improve static postural control in patients with CAI. Future research should focus on incorporating plantar massage as a treatment intervention during long-term rehabilitation protocols for individuals with CAI. Strength of Recommendation: In agreement with the Center of Evidence-Based Medicine, the consistent results from 2 crossover studies and 1 randomized controlled trial designate that there is level B evidence due to consistent, moderate- to high-quality evidence.

Validation Of A Wearable Inertial Sensor Unit To Measure Balance And Sway During Postural Tasks

Current postural control tests for baseline concussion analysis and return to play decision making are of moderate reliability, attributed to subjective scoring. A recently developed inertial measurement unit (IMU) may offer clinicians a feasible, objective tool for postural control analysis surrounding a concussive event. PURPOSE: To assess the validity of a wearable IMU against a force platform (FP) during postural control tasks in adults. METHODS: Twenty-four participants completed three trials of four stance conditions (double-leg, tandem, left leg, and right leg) with eyes open (EO) and eyes closed (EC). Concurrent measures of postural control (anterior-posterior and medial-lateral sway, path length, and sway area) during each stance were collected as participants stood on a single FP while wearing the IMU on the sternum. Statistical analyses were conducted on mean percentage change (MPC) from EO to EC for sway parameters from the FP and IMU during the four stance conditions. Multiple multivariate analyses of variances were conducted to determine whether statistical differences existed between instruments (α = 0.05). RESULTS: The differences in MPC when comparing the IMU to the FP were 5-33% for double-leg stance, 8-130% for tandem stance, 0-82% for left leg stance, and 12-178% for right leg stance across postural control measures. Significant multivariate differences were found for double-leg [F = 12.233, p < .001], tandem [F = 15.927, p < .001], left leg [F = 3.725, p = .011], and right leg [F = 4.031, p = .007] stance. Pairwise comparisons indicated significant differences for anterior-posterior sway (p = .010) and path length (p < .001) during double-leg stance and path length (p = .005) during tandem stance. CONCLUSIONS: Preliminary results indicate large differences in postural control when utilizing this IMU versus a FP for assessing sway in direct comparisons. It must be noted that sway from this IMU is projected from its center of mass. Thus, direct comparison may be misleading. Further study is suggested to incorporate the IMU projection algorithm, in order to make more appropriate direct comparisons between instruments. It is important for researchers to understand algorithms that are implemented in IMU software to determine reliability of measurement, prior to stating experimental outcomes.

Symptom profiles and postural control after concussion in female artistic athletes

ABSTRACT Objectives The purpose of our investigation was to compare post-concussion symptom profiles and postural control measures among female youth artistic athletes (gymnasts and cheerleaders) relative to female ball sport athletes (volleyball or basketball). Methods/Findings We compared 27 artistic athletes (median age = 15.0 years; evaluated median = 13 days post-injury) and 49 ball sport athletes (median age = 15.3 years; evaluated median = 10 days post-injury) within 21 days of sustaining a concussion on measures of symptom profiles and postural control (Balance Error Scoring System [BESS]), tandem gait, and Romberg tests. After adjusting for the independent effect of time from injury-evaluation, concussion history, and pre-morbid migraine history, we observed that artistic athletes performed the BESS tandem stance foam condition with fewer errors than ball sport athletes (β = −2.4; 95% CI = −4.7, −0.2; p = .03). Artistic athletes demonstrated a higher, yet not statistically significant, headache severity than ball sport athletes (median = 4.5 vs 4.0, p = .07). Conclusions Overall, artistic athletes had similar symptom profiles to ball sport athletes. Postural control measures, other than the BESS tandem stance foam condition, were not significantly different from ball sport athletes. This suggests that although their sports may require higher levels of balance, artistic athletes’ performance on post-concussion balance tests may be similar to athletes of other disciplines.

Psychometric properties and domains of postural control tests for individuals with knee osteoarthritis: a systematic review

Purpose: Individuals with knee osteoarthritis (OA) commonly demonstrate impaired postural control. Comprehensive assessment of postural control is required to identify impairments, inform appropriate management and evaluate treatment effectiveness. Our aim was to systematically review psychometric properties of tests that assess postural control in people with knee OA and secondly, to determine domains of postural control measured by these tests.

Influence of Obesity and Impact of a Physical Activity Program on Postural Control and Functional and Physical Capacities in Institutionalized Older Adults: A Pilot Study.

To evaluate the role of obesity in the effects of physical activity (PA) on postural control and functional and physical capacities in the older adults and to assess the effectiveness of a PA program on these capacities. Six obese (age = 78.8 [3.7]y; body mass index > 30kg/m2), 7 overweight (age = 80.9 [2.8]y; 25 < body mass index < 30kg/m2), and 6 normal weight (age = 80.8 [5.7]y; body mass index < 25kg/m2) older adults performed the time up and go test, the 6-minute walk test, and the Tinetti test. Static and dynamic (forward leaning) postural control tests were also assessed. All these tests were similarly assessed 4 months later, during which only the obese group and overweight group participated in a PA program. Before PA, results of the time up and go test, 6-minute walk test, Tinetti test, quiet standing, and forward lean tests revealed that physical capacities and static and dynamic postural control were impaired in the obese group when compared to the normal weight group. After PA, results of quiet standing, physical and functional tests were improved for obese group. Obesity is an additional constraint to age-related postural control and functional and physical capacities deteriorations. Nevertheless, a PA program is effective in improving balance and functional capacities in obese older adults.

Postural control processes during standing and step initiation in autism spectrum disorder

BackgroundIndividuals with autism spectrum disorder (ASD) show a reduced ability to maintain postural stability, though motor control mechanisms contributing to these issues and the extent to which they are associated with other gross motor activities (e.g., stepping) are not yet known.MethodsSeventeen individuals with ASD and 20 typically developing (TD) controls (ages 6–19 years) completed three tests of postural control during standing. During the neutral stance, individuals stood with their feet shoulder width apart. During the Romberg one stance, they stood with feet close together. During the circular sway, participants stood with feet shoulder width apart and swayed in a circular motion. The standard deviation (SD) of their center of pressure (COP) in the mediolateral (ML) and anteroposterior (AP) directions and the COP trajectory length were examined for each stance. We also assessed mutual information (MI), or the shared dependencies between COP in the ML and AP directions. Participants also completed a stepping task in which they stepped forward from one force platform to an adjacent platform. The amplitude and duration of anticipatory postural adjustments (APAs) were examined, as were the maximum lateral sway, duration, and velocity of COP adjustments following the initial step. We examined stepping variables using separate one-way ANCOVAs with height as a covariate. The relationships between postural control and stepping measures and ASD symptom severity were assessed using Spearman correlations with scores on the Autism Diagnostic Observation Schedule–Second Edition (ADOS-2) and the Autism Diagnostic Interview-Revised (ADI-R).ResultsIndividuals with ASD showed increased COP trajectory length across stance conditions (p = 0.05) and reduced MI during circular sway relative to TD controls (p = 0.02). During stepping, groups did not differ on APA amplitude (p = 0.97) or duration (p = 0.41), but during their initial step, individuals with ASD showed reduced ML sway (p = 0.06), reduced body transfer duration (p < 0.01), and increased body transfer velocity (p = 0.02) compared to controls. Greater neutral stance COPML variability (r = 0.55, p = 0.02) and decreased lateral sway (r = − 0.55, p = 0.02) when stepping were associated with more severe restricted and repetitive behaviors in participants with ASD.ConclusionsWe found that individuals with ASD showed reduced MI during circular sway suggesting a reduced ability to effectively coordinate joint movements during dynamic postural adjustments. Additionally, individuals with ASD showed reduced lateral sway when stepping indicating that motor rigidity may interfere with balance and gait. Postural control and stepping deficits were related to repetitive behaviors in individuals with ASD indicating that motor rigidity and key clinical issues in ASD may represent overlapping pathological processes.

Virtual reality in concussion management: from lab to clinic

VR-based postural control assessments suggest that visual motion is destabilizing following SRC, perhaps indicating persistent perceptual-motion disintegration when clinical postural control tests suggest complete recovery. VR can also provide functional neuropsychological assessments using real-life scenarios or virtual environments, which may be more sensitive than traditional pencil-and-paper or computerized neuropsychological assessments.

Psychometric properties and domains of postural control tests for individuals with knee osteoarthritis: a systematic review.

Individuals with knee osteoarthritis (OA) commonly demonstrate impaired postural control. We aimed to systematically review psychometric properties of tests that assess postural control in people with knee OA and secondly, to determine domains of postural control measured by these tests. PubMed, CINAHL, Embase and Web of Science databases were searched to January 2019. Two independent review authors screened references according to eligibility criteria. The Consensus-based Standards for the selection of health Measurement Instruments were used to evaluate study methodological quality. Postural control tests identified from included studies were assessed to determine postural control constructs using the Systems Framework for Postural Control identifying nine domains. Following the screening of 2643 references, five cross-sectional studies and one longitudinal study (n = 408) were included. Four studies evaluated reliability, validity or responsiveness of three clinical measures: Community Balance and Mobility Scale, Star Excursion Balance Test and Tinetti Performance Oriented Mobility Assessment. Two assessed reliability or validity of a force platform. Results showed that evidence for reliability, validity and responsiveness of all these postural measures is limited. The most common domain of postural control assessed was 'static stability'. No study used measures that evaluated all nine postural control domains. Our results highlight limited investigation of psychometric properties specific to postural control in knee OA. The few existing ones have limitations regarding psychometric robustness and completeness regarding different domains of postural control. Future research should focus on verifying the quality of existing tools to evaluate postural control in knee OA for research and clinical purposes.

Medical Resort Treatment Extended with Modern Feedback Exercises Using Virtual Reality Improve Postural Control in Breast Cancer Survivors. Preliminary Study

Introduction: Women with breast cancer have an increasing chance of survival for many years. Multimodal, extremely effective but also aggressive treatment, often leads to disorders of neuromuscular excitability and physical fitness of the patients. Therefore, when planning the physiotherapy process of women treated for breast cancer, one should look for the most effective methods of improvement with broad neurostimulatory and neuromodulatory effects. In recent years, more and more attention has been paid to the possibilities of using virtual reality exercises in therapy. Aim: The study was to understand the impact of medical resort treatment extended with modern feedback exercises using virtual reality to improve postural control in breast cancer survivors. M aterial and Methods: A clinical, pilot, non-controlled study was conducted at the Solanki Medical Resort in Inowroclaw. 46 women aged 36 to 63 completed the study (mean 51.67 ± 6.62 years). The patients participated in spa therapy for 3 weeks. For basic medical treatment, to improve postural control, physical exercises using feedback based on virtual reality were introduced. Postural control tests performed on the stabilometric platform were used to assess the progress of therapy. Results: In the assessment of dynamic postural control, the length of the center of foot pressure (COP) movement path before the treatment was on average 278.28 cm (± 147.13) and after treatment shortened to 209.60 cm (± 86.49) which was statistically significant (p = 0.0083). In the assessment of static postural control, no statistically significant differences were found between the length of the COP pathway before treatment compared to the condition before treatment (p&gt; 0.05). Conclusions: Medical treatment enriched with physical exercises using feedback based on virtual reality did not affect static postural control but contributed to the improvement of dynamic postural control. The results of the study should be confirmed in high-quality therapeutic experiments, including control groups.

Differentiating Parkinson Disease Subtypes Using Clinical Balance Measures.

People with Parkinson disease (PD) present phenotypes that are characterized as tremor-dominant (TD) or postural instability/gait difficulty (PIGD) subtypes. Differentiation of subtypes allows clinicians to predict disease course and adjust treatment. We examined whether brief mobility and balance measures can discriminate PIGD from TD phenotypes. We performed a cross-sectional study with individuals with PD (n = 104). Blinded raters assessed participants with the Unified Parkinson's Disease Rating Scale (UPDRS) or Movement Disorders Society revision (MDS-UPDRS), and balance assessments: 360° turn test, one-leg stance, a reactive postural control test, and tandem walk. Participants were classified as PIGD or TD based on the UPDRS or MDS-UPDRS assessment results. Differences in balance variables between subtypes were assessed with univariate analyses. Receiver operating characteristic (ROC) curve analyses were performed to investigate the ability of balance variables to differentiate PD subtypes. No differences between subtypes were observed for tandem walk or reactive postural control. Participants with PIGD performed worse on number of steps and time to complete the 360° turn test and on one-leg stance time. ROC curves showed only the 360° turn test discriminated PIGD from TD with high specificity (0.84). Post hoc analyses revealed that the 360° turn test is the most discriminatory for classifying PD subtypes in early stages of the disease. ROC analyses based on combined models including both the 360° test and tandem walk test performance increased the specificity to 0.97. The 360° turn test requires minimal time to administer and may be useful in mild-moderate PD for distinguishing PIGD from TD subtypes.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A295).

BalanCI: Head-Referenced Cochlear Implant Stimulation Improves Balance in Children with Bilateral Cochleovestibular Loss

Introduction: To determine the impact of a head-referenced cochlear implant (CI) stimulation system, BalanCI, on balance and postural control in children with bilateral cochleovestibular loss (BCVL) who use bilateral CI. Methods: Prospective, blinded case-control study. Balance and postural control testing occurred in two settings: (1) quiet clinical setting and (2) immersive realistic virtual environment (Challenging Environment Assessment Laboratory [CEAL], Toronto Rehabilitation Institute). Postural control was assessed in 16 and balance in 10 children with BCVL who use bilateral CI, along with 10 typically developing children. Children with neuromotor, cognitive, or visual deficits that would prevent them from performing the tests were excluded. Children wore the BalanCI, which is a head-mounted device that couples with their CIs through the audio port and provides head-referenced spatial information delivered via the intracochlear electrode array. Postural control was measured by center of pressure (COP) and time to fall using the Wii^TM (Nintendo, WA, USA) Balance Board for feet and the BalanCI for head, during the administration of the Modified Clinical Test of Sensory Interaction in Balance (CTSIB-M). The COP of the head and feet were assessed for change by deviation, measured as root mean square around the COP (COP-RMS), rate of deviation (COP-RMS/duration), and rate of path length change from center (COP-velocity). Balance was assessed by the Bruininks-Oseretsky Test of Motor Proficiency 2, balance subtest (BOT-2), specifically, BOT-2 score as well as time to fall/fault. Results: In the virtual environment, children demonstrated more stable balance when using BalanCI as measured by an improvement in BOT-2 scores. In a quiet clinical setting, the use of BalanCI led to improved postural control as demonstrated by significant reductions in COP-RMS and COP-velocity. With the use of BalanCI, the number of falls/faults was significantly reduced and time to fall increased. Conclusions: BalanCI is a simple and effective means of improving postural control and balance in children with BCVL who use bilateral CI. BalanCI could potentially improve the safety of these children, reduce the effort they expend maintaining balance and allow them to take part in more complex balance tasks where sensory information may be limited and/or noisy.

Controle postural e sensibilidade plantar em jovens e idosos

Alterações decorrentes do processo de envelhecimento podem impactar o controle postural e a sensibilidade cutânea plantar. Essas mudanças são fatores predisponentes a quedas em idosos. O objetivo do estudo foi comparar a sensibilidade cutânea plantar e o controle postural em indivíduos jovens e idosos, e buscar associações entre estas variáveis nestes dois grupos etários. Trata-se de um estudo transversal do qual participaram 63 indivíduos de ambos os sexos. Os participantes foram avaliados por meio dos testes Timed Up and Go (TUG), Apoio Unipodal e Estesiometria (por monofilamentos de nylon). Os indivíduos jovens exibiram resultados significantemente melhores que os idosos no tempo de execução do TUG, tempo de apoio unipodal e na sensibilidade plantar, avaliada pela estesiometria (p&lt;0,0001). As correlações entres as variáveis do estudo revelaram associações fracas e muito fracas (não significantes), tanto entre os jovens como entre os idosos, exceto pela associação entre tempo de apoio unipodal e estesiometria do lado direito entre os indivíduos jovens (r=-0,35, p=0,05). A sensibilidade plantar e o controle postural são menores em idosos quando comparados com os jovens, e não houve associação entre o teste clínico de controle postural e a sensibilidade plantar avaliada por estesiometria.

Re-conceptualizing postural control assessment in sport-related concussion: Transitioning from the reflex/hierarchical model to the systems model

ABSTRACT Background: While postural control impairment is common following sport-related concussion, few investigations have studied the physiological basis for this impairment. Both the Reflex/Hierarchical Model and the Systems Model are commonly used to characterize the physiological basis of postural control. Purpose: To discuss the physiological basis of postural control impairment resulting from sport-related concussion based on these models and suggest directions for future research. Methods: Narrative literature review. Findings: Postural control impairment seen with sport-related concussion is a multifaceted construct that can result from deficits in numerous systems that underlie postural control as described by the Systems Model, rather than a unidimensional construct that stems from the central nervous systems’ inability to integrate sensory input to control posture as per the Reflex/Hierarchical Model. Conclusion: We recommend a transition away from the Hierarchical/Reflex Model of postural control towards the Systems Model in the conceptualization of sport-related concussion. Future research on postural control following sport-related concussion should account for the multifaceted nature of the resulting postural control impairment based on the Systems Model. Clinically, there is a need for a clinical postural control test that allows examination across the affected systems under single-task, dual-task, and sport-specific paradigms.

Effects of Slackline Training on Acceleration, Agility, Jump Performance and Postural Control in Youth Soccer Players.

The goal of this study was to assess the effects of a supervised slackline training program in a group of soccer players. Thirty-four male division I under-19 players (16.64 ± 0.81 years) agreed to participate in the study. They were randomly divided into an experimental group (EG) and a control group (CG). The first group (EG) followed a 6-week supervised slackline training program (3 sessions/week; 5-9 min/session), while the CG performed only regular soccer training. Several variables were assessed in all participants: acceleration (20-m sprint test), agility (90º turns test), jump performance (squat jump, countermovement jump), and postural control (Center of Pressure ( CoP) testing: length, area, speed, Xmean, Ymean, Xspeed, Yspeed, Xdeviation, Ydeviation). Ratings of perceived exertion and local muscle ratings of perceived exertions were also recorded after each slackline training session. At post-tests, there was a significant increase only in the EG in acceleration, agility, squat jump and countermovement jump performance, as well as several CoP variables: area in the bipedal support on a firm surface, and length, area and speed in the left leg on a firm surface. The program was rated as “somewhat hard” by the players, while quadriceps, gastrocnemius and tibialis anterior were the most exerted muscles while slacklining. In conclusion, slackline training can be an effective training tool for young, high-level soccer players.

INTERRATER AND TEST-RETEST RELIABILITY OF THE Y BALANCE TEST IN HEALTHY, EARLY ADOLESCENT FEMALE ATHLETES

Adolescence is the stage of development marked by peak rates of skeletal growth resulting in impaired dynamic postural control and increased injury risk, especially in female athletes. Reliable tests of dynamic postural control are needed to help identify athletes with balance deficits and assess changes in limb function after injury. To estimate the interrater and test-retest (intrarater) reliability of the Y-Balance Test in a group of early adolescent females over a one-month period when administered by novice raters. Twenty-five early adolescent females (mean age 12.7 ± 0.6 years) participated. Two physical therapy student raters, randomly selected from a pool of five, simultaneously assessed each subject's performance on the Y-Balance Test and were blinded to each other's results. Twenty-one subjects returned for a second session (mean 32.3 ± 9.6 days) and were assessed by the same two raters, blinded to previous measurements. Maximum and normalized reach distances and composite scores of the right and left limbs were collected. Intraclass correlation coefficients (ICC) were calculated for between rater and between session agreement. Measurement error and minimal detectable change values were calculated for clinical interpretation. Interrater reliability was excellent for all reach directions and composite scores of the right limb (ICC 0.973-0.998) and left limb (ICC 0.960-0.999) except for the day 1 left anterior reach which was good (ICC 0.811). Test-retest reliability were moderate to excellent for the right limb (ICC 0.681- 0.908) and moderate to good for left limb (ICC 0.714 - 0.811). Minimal detectable change values for the right and left limbs ranged between 2.02-3.62% and 2.77-3.63%, respectively. The Y-Balance Test is a reliable tool to assess dynamic balance in early adolescent females and may be utilized in a clinical setting to monitor function over a one-month time interval. Between rater differences were mainly attributed to disparities in subjective test requirements and not quantitative measures of reach distance. Level 2.