The balance error scoring system learned response among young adults

Validity and reliability of the Balance Error Score System (BESS) Thai version in patients with chronic non-specific neck pain

BACKGROUND

Neck pain has been found to affect the somatosensory system, which can lead to impaired balance control. To assess the balance of patients with neck pain and other conditions, the balance error scoring system (BESS) is commonly used as a static balance measurement tool. However, this tool is seldom used in Thailand due to its English language format.

OBJECTIVE

To translate and determine the content, convergent validity, and reliability of a Thai version of the BESS tool.

MATERIAL AND METHODS

A process of cross-cultural adaptation was utilized to translate BESS into a Thai version, called BESS-TH. To assess content validity, five physical therapy lecturers specializing in the musculoskeletal field used BESS to measure balance in participants with neck pain. For the convergent validity process, 130 patients diagnosed with chronic non-specific neck pain (CNSNP) were randomly assessed using four static balance tests (BESS, Single-leg balance test (SLBT), Romberg test, and Tandem stance test). For reliability, two assessors with varying years of work experience independently assessed videos of the participants twice using the BESS-TH, with a minimum 7-day interval between assessments.

RESULTS

The BESS-TH used to assess balance of patients with neck pain demonstrated acceptable content validity (index of item objective congruence (IOC) = 0.87). The Spearman's Rank Correlation Coefficient was calculated between the BESS-TH and three other measures: the SLBT with eyes open and eyes closed, the Romberg test with eyes open and eyes closed, and the Tandem stance test with eyes open and Tandem stance test with eyes closed. The values obtained were as follows: -0.672, -0.712, -0.367, -0.529, -0.570, and -0.738, respectively. The inter-rater and intra-rater reliability were 0.922 (95% CI = 0.864-0.956) and 0.971 (95% CI = 0.950-0.983), respectively. Minimum detectable change (MDC) for the total BESS score of inter-rater and intra-rater reliability were 7.16 and 4.34 points, respectively.

CONCLUSION

The BESS-Thai version was acceptable, reliable, and valid for evaluating balance performance in patients with CNSNP. This tool can be used and applied to clinically evaluate postural control in Thailand.

The Convergent Validity of the SWAY Balance Application to Assess Postural Stability in Military Cadets Recovering from Concussion

Background

Concussions are often accompanied by balance disturbances. Clinically accurate evaluation systems are often expensive, large, and inaccessible to most clinicians. The Sway Balance Mobile Application (SWAY) is an accessible method to quantify balance changes.

Purpose

To determine the known groups and convergent validity of the SWAY to assess balance after a concussion.

Study Design

Case-Control Study.

Methods

Twenty participants with acute concussion and twenty controls were recruited. At initial, one-week, and final return to activity (RTA) evaluations, all participants completed the Sports Concussion Assessment Tool (SCAT-5), and balance control measured by SWAY mBESS and NeuroCom Balance Master Sensory Organization Test (SOT). Mixed model ANOVAs were used to detect differences in SWAY mBESS and NeuroCom SOT scores with time (initial, one-week, final RTA) as the within-subjects factor and group (concussed, healthy) as the between-subjects factor. Spearman's Rho correlations explored the associations between NeuroCom SOT scores, SWAY scores, SCAT-5 symptom scores, and time in days to final RTA.

Results

The sampled population was predominantly male and age (20 ± 1), and BMI differences were insignificant between groups. The SWAY did not detect differences between healthy and concussed participants and did not detect change over time [F(2,40) = .114, p = 0.89; F(2,40)= .276, p =0.60]. When assessing the relationship between the SWAY and the SOT, no correlation was found at any time point (r = -0.317 to -0.062, p > 0.05). Time to RTA demonstrated a moderate correlation with both SCAT-5 symptom severity score (r = .693, p < 0.01) and SCAT-5 total symptom score (r = .611, p < 0.01) at the one-week follow-up.

Conclusion

The SWAY mBESS does not appear to be a valid balance assessment for the concussed patient. The SWAY mBESS in patients with concussion failed to demonstrate convergent validity and did not demonstrate an ability to validate known groups. When assessing the time to final RTA, the one-week post-initial assessment SCAT-5 symptom severity and total scores may help determine the length of recovery in this population.

Level of Evidence

Level 3.

Footwear Type and Testing Environment Do Not Affect Baseline Modified Balance Error Scoring System Performance Among Middle School Athletes

CONTEXT

Limited evidence exists to demonstrate the effect of extrinsic factors, such as footwear worn or the testing environment, on performance of the modified balance error scoring system (mBESS) in the middle school age (10-14 y) population. Therefore, the purpose of our study was to investigate the effect of footwear types and testing environments on performance of the mBESS by middle school athletes.

DESIGN

Cross-sectional.

METHODS

In total, 2667 middle school athletes (55.9% boys and 44.1% girls; age = 12.3 [0.94] y) were administered the mBESS while wearing their self-selected footwear (barefoot, cleats, or shoes) either indoors (basketball court) or outdoors (football field or track). The number of errors committed (range = 0-10) during the double-leg, single-leg, and tandem stances of the mBESS were summed to calculate a total score (range = 0-30). Kruskal-Wallis tests were used to assess for differences among the footwear groups for each mBESS stance and the total score. Mann-Whitney U tests with calculated nonparametric effect sizes (r) were used to assess for differences between the footwear groups and testing environments when appropriate.

RESULTS

There were significant differences for the number of committed errors among the footwear groups in the single-leg (P < .001) and tandem (P < .001) stances of the mBESS and mBESS total scores (P < .001). Significantly fewer errors (better) were committed while wearing shoes compared with other footwear in the single-leg and tandem stances of the mBESS (Ps ≤ .032, r = .07-.13). Participants assessed indoors committed significantly fewer errors than those assessed outdoors in each stance of the mBESS (Ps ≤ .022, r = .04-.14). Lower (better) mBESS total scores were observed for participants while wearing shoes (Ps ≤ .002, r = .10-.15) or assessed indoors (P = .001, r = .14).

CONCLUSIONS

Although our data suggest that the type of footwear worn and the testing environment have a significant effect on mBESS scores of middle school athletes, the magnitudes of these differences are negligible.

Quantitative Assessment of Balance for Accurate Prediction of Return to Sport From Sport-Related Concussion

BACKGROUND

Determining when athletes are able to return to sport after sports-related concussion (SRC) can be difficult.

HYPOTHESIS

A multimodal algorithm using cognitive testing, postural stability, and clinical assessment can predict return to sports after SRC.

STUDY DESIGN

Prospective cohort.

LEVEL OF EVIDENCE

Level 2b.

METHODS

Athletes were evaluated within 2 to 3 weeks of SRC. Clinical assessment, Immediate Post Concussion and Cognitive Testing (ImPACT), and postural stability (Equilibrate) were conducted. Resulting data and machine learning techniques were used to optimize an algorithm discriminating between patients ready to return to sports versus those who are not yet recovered. A Fisher discriminant analysis with leave-one-out cross-validation assessed every combination of 2 to 5 factors to optimize the algorithm with lowest combination of type I and type II errors.

RESULTS

A total of 193 athletes returned to contact sports after SRC at a mean 84.6 days (±88.8). Twelve subjects (6.2%) sustained repeat SRC within 12 months after return to sport. The combination of (1) days since injury, (2) total symptom score, and (3) nondominant foot tandem eyes closed postural stability score created the best algorithm for discriminating those ready to return to sports after SRC with lowest type I error (13.85%) and type II error (11.25%). The model was able to discriminate between patients who were ready to successfully return to sports versus those who were not with area under the receiver operating characteristic (ROC) curve of 0.82.

CONCLUSION

The algorithm predicts successful return to sports with an acceptable sensitivity and specificity. Tandem balance with eyes closed measured with a video-force plate discriminated athletes ready to return to sports from SRC when combined in multivariate analysis with symptom score and time since injury. The combination of these factors may pose advantages over computerized neuropsychological testing when evaluating young athletes with SRC for return to contact sports.

CLINICAL RELEVANCE

When assessing young athletes sustaining an SRC in a concussion clinic, measuring postural stability in tandem stance with eyes closed combined with clinical assessment and cognitive recovery is effective to determine who is ready to successfully return to sports.

A New In-Skates Balance Error Scoring System for Ice Hockey Players

OBJECTIVE

Evaluate a new in-skates balance error scoring system (SBESS) for ice hockey players wearing their equipment.

DESIGN

Prospective, randomized, single blinded study.

SETTING

Sport Medicine Clinic.

PARTICIPANTS

Eighty university hockey players.

INTERVENTION

A control group performed the SBESS assessment at rest on 2 separate occasions and an experimental group performed the assessment at rest and after exertion. The SBESS consists of maintaining different stances on ice skates for 20 seconds each, while wearing full equipment (no stick, gloves and helmet) and standing on a hard rubber surface. Three independent reviewers scored the video recorded assessments.

MAIN OUTCOMES MEASURES

Primary outcome was the number of balance errors and the secondary outcome was the number of falls.

RESULTS

The control group's median SBESS scores were 2 and 3 on the first and second attempts at rest, respectively. The experimental group's median SBESS scores were 2 at rest and 2 after exertion. There was no fatigue effect and no athletes fell while performing the test. Of the 4 stances tested, the tandem stance had the highest variability in error scores between athletes and when repeated by the same athlete. The intraclass correlation coefficient (ICC) for interrater reliability was above 0.82, and the intrarater reliability ICC was above 0.86 for all SBESS scores. There was no concordance between the SBESS and the modified BESS.

CONCLUSIONS

The SBESS, omitting the tandem stance, is a safe and reproducible sideline balance assessment of ice hockey players wearing full equipment.

Evaluation of the vestibular and ocular motor screening (VOMS) as a prognostic tool for protracted recovery following paediatric sports-related concussion

Objective

To understand the relationship between initial vestibular and ocular motor screening (VOMS) and recovery time, and the utility of VOMS to screen for protracted recovery in youth/adolescent patients with sport-related concussion (SRC).

Methods

Participants (8–18 years) who were diagnosed with an SRC within 7 days of the injury were administered the VOMS test by certified medical personnel. Recovery time (days) and protracted recovery (>30 days) were the primary outcomes. Multivariable regression models were used to evaluate the association between VOMS symptom provocation and (1) recovery time (days) and (2) protracted recovery. Measures of VOMS validity, predictive ability and receiver operator curves were used to assess VOMS as a prognostic tool to accurately classify a normal/protracted recovery.

Results

After adjustment, any symptom provocation across all VOMS domains was associated (p<0.05) with greater recovery time, except the convergence test (p=0.08) in females. All VOMS test thresholds (≥1 to ≥10) in males and (≥1 to ≥5) in females were associated (p<0.05) with recovery time. However, the VOMS test performed poorly among males (receiver operating characteristic (ROC) area=0.66) and failed among females (ROC area=0.56) as a prognostic tool to identify those that will have a normal/protracted recovery.

Conclusion

In this sample, overall, the VOMS test was associated with recovery time (days); however, the VOMS was not a valid stand-alone prognostic tool to identify a delayed recovery, but may be useful in combination with other concussion symptomology assessments. Future studies should confirm these findings in larger samples while taking into consideration other comorbid factors that may influence recovery time.

The Toronto concussion study: a cross-sectional analysis of balance deficits following acute concussion in community-dwelling adults

Objective: To characterize balance deficits in community-dwelling adults following acute concussion.Design: Cross-sectional observational study.Methods: Individuals with acute concussion (n=100) and healthy controls (n=20) completed the BESS (Balance Error Scoring System) and quiet standing trials on forceplates with the eyes open, closed, or during a cognitive dual task. BESS score and centre-of-pressure root mean square and high-frequency power (0.4-3Hz) were used to characterize group differences. In a secondary analysis, participants were subdivided based on self-reported symptoms of balance problems and dizziness using the SCAT-3 (Sport Concussion Assessment Tool - Third Edition) Symptom Checklist.Results: In comparing individuals with concussion and controls, BESS score (16.0 ± 6.0 vs 12.6 ± 3.8; F(1,116) = 5.814, p = .017) and anteroposterior [F(1.78, 204.2) = 11.93, p < .001] and mediolateral [F(1, 114) = 10.05, p = .002] high-frequency power revealed significant group differences. Dividing individuals based on self-reported symptoms revealed significant differences in mediolateral high frequency power, such that participants reporting balance and dizziness problems as well as those participants not reporting balance or dizziness symptoms following concussion were less stable than controls.Conclusions: Deficits in clinical and posturographic measures of balance occur in community-dwelling adults with concussion. These measures do not align with self-reported balance symptoms. Future research and clinical practice aimed at careful selection of optimized balance assessment is recommended.

Instrumented balance assessment in mild traumatic brain injury: Normative values and descriptive data for acute, sub-acute and chronic populations

Often the Balance Error Scoring System (BESS) is used to assess balance during a clinical evaluation of a patient presenting with mild Traumatic Brain Injury (mTBI). Although recent research has shown the benefits of using inertial sensor measures such as the Root Mean Square (RMS) of the acceleration in place of clinical scoring, few normative data are available for clinicians to reference. The purpose of this paper was to provide normative data collected using wearable sensors for healthy controls across three age groups, as well as providing cohort data for mTBI participants across three stages following injury (acute, sub-acute and chronic). The RMS in the Medio-Lateral direction (ML RMS sway) of each condition (double stance – DS; single stance – SS; and tandem stance – TS) was extracted per participant for analysis. The average ML RMS sway across all conditions was also calculated (ML RMS-Av). Percentiles were calculated to provide normative data, and two multivariate general linear models were used to evaluate differences between 1) non-athlete controls, athlete controls, and athletes with acute mTBI, and 2) non-athletic cohorts of control, sub-acute and chronic mTBI groups across young, middle-aged, and older adults. Model 1 revealed athletes with acute mTBI had more ML RMS sway than athlete controls the for the DS condition ( p < 0.001), but no differences with non-athlete controls. Athlete controls also had less ML RMS sway for the SS condition and ML RMS-Av ( p ≤ 0.022) compared with non-athlete controls. Model 2 revealed less ML RMS sway in the control group than the sub-acute and chronic mTBI groups for DS ( p ≤ 0.004), but no differences between the sub-acute and chronic group, while more ML RMS sway occurred in the chronic group compared with the control and sub-acute groups for the TS condition and ML RMS-Av ( p ≤ 0.013). Older adults had more ML RMS sway than young and middle-aged adults for SS, TS and ML RMS-Av ( p ≤ 0.019), while there were no differences between the young and middle-aged adults. Normative values presented here can help increase the practical application of instrumented balance assessment of mTBI patients through wearable sensors. ML RMS sway in the DS condition provided the clearest distinction between control and mTBI groups, but we caution that young adult athletes need to be assessed against athletic peers in the absence of baseline normative values. In non-athlete cohorts, age and gender norms may not be necessary to consider when assessing DS performance; however, age may be an important factor to consider when accessing norms for other stance conditions or the average performance across all conditions.

Centre of pressure velocity shows impairments in NCAA Division I athletes six months post-concussion during standing balance

Sport-related concussion return to play (RTP) decisions are largely based on the resolution of self-reported symptoms and neurocognitive function. Some evaluators also incorporate balance; however, an objective approach to balance that can detect effects beyond the acute condition is warranted. The purpose of this study is to examine linear measures of biomechanical balance up to 6 months post-concussion, and to present preliminary diagnostic thresholds useful for RTP. Each concussed athlete participated in instrumented standing balance tasks at 4 timepoints post-concussion. The measures from concussed athletes were compared to the sport-matched non-concussed athlete group at each timepoint. Centre of pressure (COP) mediolateral (ML) velocity in double-leg stance on a hard surface discriminated well between non-concussed and concussed athletes. COP anterior-posterior (AP) velocity in tandem stance on foam showed sensitivity to concussion. Sixty per cent of athletes at 6 months post-concussion did not recover to within the proposed COP ML velocity threshold in double-leg stance on a hard surface. Seventy-one per cent of athletes at 6 months post-concussion did not recover to within the COP AP velocity threshold in tandem stance on foam. This lack of recovery potentially indicates vestibular and motor control impairments long past the typical period of RTP.

A preliminary cross-sectional assessment of postural control responses to continuous platform rotations following a sport-related concussion

BACKGROUND

Individuals suffering a sport-related concussion typically recover within 1 month; however, persistent post-concussive symptoms are known to occur beyond this period. Clinical guidelines may not be sufficient to determine if dynamic postural control is still impaired at the point of the return to play decision.

RESEARCH QUESTION

Do individuals with a previous sport-related concussion who have returned to play show differences in postural control compared to individuals without a previous concussion, in response to continuous platform perturbations?

METHODS

Eight previously concussed and eight age- and position-matched participants completed six one-minute trials (three with eyes open/closed) whilst stood on a moving platform that rotated about the pitch axis with a peak-to-peak amplitude of 4° at a frequency of 0.8 Hz. Six trials were also captured during static quiet stance for comparison. Reactive and anticipatory stages of postural control were analysed by determining anteroposterior margins of stability (MoS) as a measure of whole-body postural control and head-to-trunk anchoring index as an indication of the head-trunk segmental coupling strategy.

RESULTS

Posterior MoS during platform rotations reduced for both groups during eyes closed trials, but previously concussed participants exhibited a significantly greater reduction (1.97 cm) in comparison to matched-controls (0.34 cm). Participants, regardless of group, showed a preference towards a head-stabilised-to-trunk strategy during platform rotations. There were no differences during static trials.

SIGNIFICANCE

This preliminary study suggests previously concussed athletes demonstrate a greater reduction in postural control whilst undergoing continuous platform rotations with eyes closed, which could indicate possible lingering deficits to other sensory systems such as the vestibular system, though participants were not likely to lose their balance.

Sway Balance Mobile Application: Reliability, Acclimation, and Baseline Administration

OBJECTIVES

To describe historic baseline session administration practices, to assess the utility of a practice trial (an acclimation trial) before the official balance session, and to examine the within-session reliability of the Sway Balance Mobile Application (SBMA).

DESIGN

Retrospective observational study.

SETTING

Middle schools, high schools, and colleges across the United States.

PARTICIPANTS

More than 17 000 student-athletes were included in the Sway Medical database with 7968 individuals meeting this study's inclusion criteria.

INDEPENDENT VARIABLES

The Sway Medical database included the following subject characteristics for each student-athlete: age, sex, weight, and height.

MAIN OUTCOME MEASURES

Balance assessment score generated by the SBMA.

RESULTS

Variable administration practices with significant differences between baseline session averages across methods were found. Individuals who performed an acclimation trial had a significantly higher baseline session average than those who did not. Within-session reliability estimates were in the low to adequate range (r = 0.53-0.78), with higher estimates found for 2 consecutive baseline tests (r = 0.75-0.78).

CONCLUSIONS

For maximum clinical utility, a standardized protocol for postural control baseline acquisition is necessary. Acclimation trial should be administered before a baseline session to minimize variability, especially with only 1 to 2 baseline tests. The highest reliability was observed across 2 consecutive baseline tests within the same baseline session. We suggest obtaining baseline balance measurements with an acclimation trial followed by a baseline session with 2 baseline tests. Prospective studies are required for validation.

Assessment of Long-Term Effects of Sports-Related Concussions: Biological Mechanisms and Exosomal Biomarkers

Concussion or mild traumatic brain injury (mTBI) in athletes can cause persistent symptoms, known as post-concussion syndrome (PCS), and repeated injuries may increase the long-term risk for an athlete to develop neurodegenerative diseases such as chronic traumatic encephalopathy (CTE), and Alzheimer's disease (AD). The Center for Disease Control estimates that up to 3.8 million sport-related mTBI are reported each year in the United States. Despite the magnitude of the phenomenon, there is a current lack of comprehensive prognostic indicators and research has shown that available monitoring tools are moderately sensitive to short-term concussion effects but less sensitive to long-term consequences. The overall aim of this review is to discuss novel, quantitative, and objective measurements that can predict long-term outcomes following repeated sports-related mTBIs. The specific objectives were (1) to provide an overview of the current clinical and biomechanical tools available to health practitioners to ensure recovery after mTBIs, (2) to synthesize potential biological mechanisms in animal models underlying the long-term adverse consequences of mTBIs, (3) to discuss the possible link between repeated mTBI and neurodegenerative diseases, and (4) to discuss the current knowledge about fluid biomarkers for mTBIs with a focus on novel exosomal biomarkers. The conclusions from this review are that current post-concussion clinical tests are not sufficiently sensitive to injury and do not accurately quantify post-concussion alterations associated with repeated mTBIs. In the current review, it is proposed that current practices should be amended to include a repeated symptom inventory, a cognitive assessment of executive function and impulse control, an instrumented assessment of balance, vestibulo-ocular assessments, and an improved panel of blood or exosome biomarkers.

Evaluating and Differentiating Ankle Instability

Given the prevalence of lateral ankle sprains during physical activity and the high rate of reinjury and chronic ankle instability, clinicians should be cognizant of the need to expand the evaluation of ankle instability beyond the acute time point. Physical assessments of the injured ankle should be similar, regardless of whether this is the initial lateral ankle sprain or the patient has experienced multiple sprains. To this point, a thorough injury history of the affected ankle provides important information during the clinical examination. The physical examination should assess the talocrural and subtalar joints, and clinicians should be aware of efficacious diagnostic tools that provide information about the status of injured structures. As patients progress into the subacute and return-to-activity phases after injury, comprehensive assessments of lateral ankle-complex instability will identify any disease and patient-oriented outcome deficits that resemble chronic ankle instability, which should be addressed with appropriate interventions to minimize the risk of developing long-term, recurrent ankle instability.

POST-CONCUSSIVE CHANGES IN BALANCE AND POSTURAL STABILITY MEASURED WITH CANESENSE™ AND THE BALANCE ERROR SCORING SYSTEM (BESS) IN DIVISION I COLLEGIATE FOOTBALL PLAYERS: A CASE SERIES

INTRODUCTION

Impairments in postural stability have been identified following sports-related concussion. CaneSense™ is a recently developed mobile lower limb motion capture system and mobile application for movement assessment which provides an objective measure of postural stability. One of the components within CaneSense™ is the Post-Concussive Excursion Index (PCEI), a measure of postural stability expressed as a percentage of symmetry between lower limbs.

PURPOSE

The purpose of this case series is to examine pre- and post-concussion differences using two separate measures, CaneSense™, and a known test, the Balance Error Scoring System (BESS), in Division I collegiate football players.

METHODS

A convenience sample of eight football players diagnosed with a concussion, were the subjects in this case series. All subjects underwent baseline testing prior to the start of pre-season camp consisting of the single limb stance (SLS) test with CaneSense™ and the BESS test. Twenty-four to 72 hours following their concussion, SLS with CaneSense™ test and the BESS test, were administered. Segmental excursions for the thigh and shank segments for each lower limb were combined into the Post-Concussion Excursion Profile (PCEP), which represents each segment's maximum excursion in the medial-lateral and anterior-posterior direction. The PCEI is a single metric generated to quantify differences within subjects by comparing the PCEP value between lower limbs during SLS where 100% suggests absolute symmetry.

RESULTS

The PCEI value decreased significantly post-concussion (41.43 ± 15.53% vs. 87.41 ± 6.05%, p < 0.001) demonstrating a 52.6% decrease in inter-limb symmetry when compared to baseline values. There was an unanticipated 36.36% improvement in composite BESS performance post-concussion (10.5 ± 4.87 errors vs. 16.5 ± 8.49 errors, p = 0.10).

CONCLUSIONS

Differences in inter-limb postural stability were found in subjects post-concussion. By assessing postural stability in both lower limbs individually, using the PCEI, impairments were detected that otherwise would have likely gone undiagnosed using the BESS test alone.

LEVELS OF EVIDENCE

Therapy, Level 4.

Longitudinal Assessment of Balance and Gait After Concussion and Return to Play in Collegiate Athletes

CONTEXT

In longitudinal studies tracking recovery after concussion, researchers often have not considered the timing of return to play (RTP) as a factor in their designs, which can limit the understanding of how RTP may affect the analysis and resulting conclusions.

OBJECTIVE

To evaluate the recovery of balance and gait in concussed athletes using a novel linear mixed-model design that allows an inflection point to account for changes in trend that may occur after RTP.

DESIGN

Cohort study.

SETTING

University athletics departments, applied field setting.

PATIENTS OR OTHER PARTICIPANTS

Twenty-three concussed (5 women, 18 men; age = 20.1 ± 1.3 years) and 25 healthy control (6 women, 19 men; age = 20.9 ± 1.4 years) participants were studied. Participants were referred by their team athletic trainers.

MAIN OUTCOME MEASURE(S)

Measures consisted of the Balance Error Scoring System (BESS) total score, sway (instrumented root mean square of mediolateral sway), single-task gait speed, gait speed while simultaneously reading a handheld article (dual-task gait speed), dual-task cost of reading on gait speed, and dual-task cost of walking on reading.

RESULTS

We observed no significant effects or interactions for the BESS. Instrumented sway was worse in concussed participants, and a change in the recovery trend occurred after RTP. We observed group and time effects and group × time and group × RTP change interactions (P ≤ .046). No initial between-groups differences were found for single-task or dual-task gait. Both groups increased gait speed initially and then leveled off after the average RTP date. We noted time and RTP change effects and positive group × time interactions for both conditions (P ≤ .042) and a group × RTP change interaction for single-task gait speed (P = .005). No significant effects or interactions were present for the dual-task cost of reading on gait speed or the dual-task cost of walking on reading.

CONCLUSIONS

Changes in the rate of recovery were coincident with the timing of RTP. Although we cannot suggest these changes were a result of the athletes returning to play, these findings demonstrate the need for further research to evaluate the effects of RTP on concussion recovery.

Reference values for the Balance Error Scoring System as measured by the Tekscan MobileMat™ in a physically active population

OBJECTIVES

The Balance Error Scoring System (BESS) is commonly used to measure postural stability; however, it has demonstrated inconsistent reliability values when administered by humans. The Tekscan MobileMat™ was developed to automate the assessment of BESS errors and eliminate rater subjectivity. The objective of this study was to report reference values for the BESS, as measured by the MobileMat™, and examine the effect of sex, concussion history, and competitive sport level on BESS performance.

METHODS

Four hundred and forty participants performed the BESS on the MobileMat™. Participants were asked to maintain each stance with their eyes closed for 20 s. The MobileMat™ was used to quantify the number of errors.

RESULTS

Concussion history (p = 0.279-0.979) and competitive sport level (p = 0.422-0.979) did not affect BESS performance. Males performed significantly better than females for the single-limb foam stance (p = 0.032). No sex differences were detected for the other BESS stances or BESS total score (p = 0.067-0.744).

CONCLUSIONS

Previously reported reference values in collegiate athletes and adolescents were slightly higher thus highlighting the value in establishing population norms and in developing new technologies to objectively quantify BESS performance. Furthermore, sex, concussion history, and competitive sport level do not appear to influence BESS performance as measured by the MobileMat™.

Normative Performance on the Balance Error Scoring System by Youth, High School, and Collegiate Athletes

CONTEXT

  Annually, more than 1 million youth athletes in the United States receive or are suspected of receiving a concussion. The Balance Error Scoring System (BESS) is the most commonly used clinical balance evaluation designed to provide a better understanding of the motor-control processes of individuals with concussion. Despite the widespread use of the BESS, a fundamental gap exists in applying this tool to young athletes, as normative values are lacking for this population.

OBJECTIVE

  To determine age- and sex-specific normative values for the BESS in youth, high school, and collegiate athletes.

DESIGN

  Cross-sectional study.

SETTING

  Local youth sport organizations, high schools, and colleges.

PATIENTS OR OTHER PARTICIPANTS

  Student-athletes (N = 6762) completed preseason baseline concussion testing as part of a comprehensive concussion-management program. Groups were youth males aged 5 to 13 years (n = 360), high school males aged 14 to 18 years (n = 3743), collegiate males aged 19 to 23 years (n = 497), youth females aged 5 to 13 years (n = 246), high school females aged 14 to 18 years (n = 1673), and collegiate females aged 19 to 23 years (n = 243).

MAIN OUTCOME MEASURE(S)

  Errors according to the BESS specifications.

RESULTS

  Performance on the BESS was worse ( P < .01) in youth athletes than in high school and collegiate athletes. In the youth and high school cohorts, females exhibited better scores than males ( P < .05). Sex was not a factor for collegiate athletes. Data from the youth cohort were further subdivided into 4-year bins to evaluate potential motor-development differences. The error count was highest for 5- to 9-year-old males and decreased with age.

CONCLUSIONS

  Performance on the BESS depended on sex and age, particularly in youth athletes. These sex- and age-specific normative values provide a reference to facilitate and unify clinical decision making across multiple providers caring for youth athletes with concussions.

Correlating the King-Devick Test With Vestibular/Ocular Motor Screening in Adolescent Patients With Concussion: A Pilot Study

BACKGROUND

The King-Devick (K-D) test is a rapid number-naming task that has been well validated as a sensitive sideline performance measure for concussion detection. Patients with concussion take significantly longer to complete the K-D test than healthy controls. Previous research suggests that ocular motor deficits, specifically saccadic abnormalities, may be an underlying factor for the prolonged time. However, these findings have not been studied at length.

HYPOTHESIS

K-D testing time of concussed adolescents at the initial clinical concussion visit will positively correlate with vestibular/ocular motor screening (VOMS) total scores.

STUDY DESIGN

Case series.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 71 patient charts were retrospectively analyzed between October 1, 2016, and January 31, 2017. Included charts consisted of patients between the ages of 10 and 18 years with a diagnosis of concussion and who had completed K-D testing and VOMS assessment at the initial physician visit. Univariate correlation between K-D testing time and the 7 VOMS items was assessed using Pearson correlation coefficients.

RESULTS

K-D testing time strongly correlated with all 7 VOMS items ( r(69) = 0.325-0.585, P < 0.01). In a linear regression model that accounted for each VOMS item, the convergence (near point) item and the visual motion sensitivity item significantly predicted K-D testing time (β = 0.387, t(63) = 2.81, P < 0.01 and β = 0.375, t(63) = 2.35, P = 0.02, respectively). Additionally, 37.5% of the 24 patients with worsening symptoms after K-D testing freely reported increased visual problems.

CONCLUSION

Our study suggests that prolonged K-D testing times in adolescents with concussion may be related to subtypes of vestibular/ocular motor impairment that extend beyond saccadic abnormalities.

CLINICAL RELEVANCE

Poor K-D testing performance of adolescents with concussion may indicate a range of vestibular/ocular motor deficits that need to be further identified and addressed to maximize recovery.

Comparison of Uninjured and Concussed Adolecent Athletes on the Concussion Balance Test (COBALT)

BACKGROUND AND PURPOSE

Dizziness and balance problems are common symptoms following sports-related concussion (SRC). Most sports require high-level balance skills that integrate the sensory inputs used for balance. Thus, a comprehensive assessment of postural control following SRC is recommended as an integral part of evaluation and management of the injury. The purpose of this exploratory study was to examine performance differences between uninjured and concussed athletes on the Concussion Balance Test (COBALT), as well as complete preliminary analyses of criterion-related validity and reliability of COBALT.

METHODS

COBALT is an 8 condition test developed for both preseason and postinjury assessment using force plate technology to measure sway velocity under dynamic postural conditions that challenge the vestibular system. Retrospective COBALT data obtained through chart review for 132 uninjured athletes and 106 concussed age-matched athletes were compared.

RESULTS

All uninjured athletes were able to complete the assessment, compared with only 55% of concussed athletes. Concussed athletes committed significantly more errors than uninjured athletes. Sway velocity for concussed athletes was higher (worse) than that for uninjured athletes on 2 conditions in COBALT.

DISCUSSION AND CONCLUSIONS

By examining an athlete's ability to complete the protocol, error rate, and sway velocity on COBALT postinjury, the clinician can identify balance function impairment, which may help the medical team develop a more targeted treatment plan, and provide objective input regarding recovery of balance function following SRC.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A204).

Postural Control and Head Impact Exposure in Youth Football Players: Comparison of the Balance Error Scoring System and a Force Plate Protocol

Postural control testing is often used by clinicians and athletic trainers to assess the health of athletes during recovery from a concussion. Characterization of postural control as a clinical tool for use with youth athletes is limited though. The objective of this study was to compare performance on the Balance Error Scoring System (BESS) and a force plate protocol at the beginning and end of a season of football within a cohort of 34 healthy youth football players (average age of 9.9 ± 0.6 y). A secondary aim was to investigate if changes in measures of balance from the postseason to the preseason were correlated with head impact exposure. Players completed testing at the beginning and end of the youth football season. There were no significant differences between BESS scores before the season and after the season (P = .54). Performance on the BESS was not associated with any of the center of pressure metrics considered in this study. No correlation was observed between measures of balance and head impact exposure for the season. Further research is required to determine the viability of postural control testing with this population.

Sub-concussive trauma, acute concussion, and history of multiple concussions: Effects on quiet stance postural control stability

Although balance control has been studied extensively following acute concussion, little is known regarding repetitive sub-concussive head impacts or chronic exposure to multiple concussive events. Quiet stance postural control was characterized in contact sport athletes at pre-season (n = 135) and post-season (n = 48) to evaluate the effects of subconcussive trauma to the head. To determine the impact of acute concussion on postural control, athletes diagnosed with a concussion during the season (n = 12) were tested at 72-h, 2-weeks, and 1-month post-injury. Because only 4 of the concussed athletes completed baseline testing, control athletes (n = 12) matched for sport, age, body mass index (BMI), and previous concussion history served as a comparison group. Finally, the effects of previous concussion history on quiet stance postural control were determined by comparing pre-season data in contact sport athletes with either zero (Hx⁰, n = 50) or three or more (Hx³⁺, n = 25) previous concussions. A force plate was used to compare changes in centre-of-pressure root-mean-square displacement (RMSdisp) and mean-velocity (COPvel) in the anterior/posterior (AP) and medial/lateral (ML) directions. One-minute trials were performed with feet hip-width apart, hands-on-hips, and A) eyes-open and B) eyes-closed. Biomechanical head-impact exposure (impacts over 10 g) was indexed over the season using mastoid-fixed impact sensors. In acutely injured athletes, repeated-measures ANOVA revealed a significant effect of time for RMSdisp AP with increased displacement at 2 weeks compared to 72 h (p = 0.008, 95% CI: -0.180, -0.310 cm). No other COP variables were affected by acute concussion. Moreover, there was no effect of concussion history or repeated sub-concussive impacts on any quiet stance metric. Additionally, head-impact exposure metrics were not correlated with COP metrics. Taken together, the data suggests alterations in COP sway during quiet stance persist in the acute 2-week period after injury. These findings were not present with either a history of multiple concussions or exposure to sub-concussive head impacts indicating acute concussion does not have appear to have long term effects for these measures.

Longitudinal Improvement in Balance Error Scoring System Scores among NCAA Division-I Football Athletes

The Balance Error Scoring System (BESS) is a commonly used concussion assessment tool. Recent studies have questioned the stability and reliability of baseline BESS scores. The purpose of this longitudinal prospective cohort study is to examine differences in yearly baseline BESS scores in athletes participating on an NCAA Division-I football team. NCAA Division-I freshman football athletes were videotaped performing the BESS test at matriculation and after 1 year of participation in the football program. Twenty-three athletes were enrolled in year 1 of the study, and 25 athletes were enrolled in year 2. Those athletes enrolled in year 1 were again videotaped after year 2 of the study. The paired t-test was used to assess for change in score over time for the firm surface, foam surface, and the cumulative BESS score. Additionally, inter- and intrarater reliability values were calculated. Cumulative errors on the BESS significantly decreased from a mean of 20.3 at baseline to 16.8 after 1 year of participation. The mean number of errors following the second year of participation was 15.0. Inter-rater reliability for the cumulative score ranged from 0.65 to 0.75. Intrarater reliability was 0.81. After 1 year of participation, there is a statistically and clinically significant improvement in BESS scores in an NCAA Division-I football program. Although additional improvement in BESS scores was noted after a second year of participation, it did not reach statistical significance. Football athletes should undergo baseline BESS testing at least yearly if the BESS is to be optimally useful as a diagnostic test for concussion.

Sensor-Based Balance Measures Outperform Modified Balance Error Scoring System in Identifying Acute Concussion

Balance assessment is an integral component of concussion evaluation and management. Although the modified balance error scoring system (mBESS) is the conventional clinical tool, objective metrics derived from wearable inertial sensors during the mBESS may increase sensitivity in detecting subtle balance deficits post-concussion. The aim of this study was to identify which stance condition and postural sway metrics obtained from an inertial sensor placed on the lumbar spine during the mBESS best discriminate athletes with acute concussion. Fifty-two college athletes in the acute phase of concussion and seventy-six controls participated in this study. Inertial sensor-based measures objectively detected group differences in the acutely concussed group of athletes while the clinical mBESS did not (p < 0.001 and p = 0.06, respectively). Mediolateral postural sway during the simplest condition of the mBESS (double stance) best classified those with acute concussion. Inertial sensors provided a sensitive and objective measure of balance in acute concussion. These results may be developed into practical guidelines to improve and simplify postural sway analysis post-concussion.

Quantification of postural control deficits in patients with recent concussion: An inertial-sensor based approach

BACKGROUND

The aim of this study was to quantify postural control ability in a group with concussion compared with a healthy control group.

METHOD

Fifteen concussion patients (4 females, 11 males) and a group of fifteen age- and sex-matched controls were recruited. Participants were tested during the performance of the three stance variants (bilateral, tandem and unilateral) of the balance error scoring system standing on a force place, while wearing an inertial measurement unit placed at the posterior aspect of the sacrum.

FINDINGS

The area of postural sway was computed using the force-plate and the '95% ellipsoid volume of sway' was computed from the accelerometer data. Concussed patients exhibited increased sway area (1513mm² [95% CI: 935 to 2091mm²] vs 646mm² [95% CI: 519 to 772mm²]; p=0.02) and sway volume (9.46m³s^-6 [95% CI: 8.02 to 19.94m³s^-6] vs 2.68m³s^-6 [95% CI: 1.81 to 3.55m³s^-6]; p=0.01) in the bilateral stance position of the balance error scoring system. The sway volume metric also had excellent accuracy in identifying task 'errors' (tandem stance: 91% accuracy [95% CI: 85-96%], p<0.001; unilateral stance: 91% accuracy [95% CI: 86-96%], p<0.001).

INTERPRETATION

Individuals with concussion display increased postural sway during bilateral stance. The sway volume that was calculated from the accelerometer data not only differentiated a group with concussion from a healthy control group, but successfully identified when task errors had occurred. This may be of value in the development of a pitch-side assessment system for concussion.

Correlation of Head Impacts to Change in Balance Error Scoring System Scores in Division I Men's Lacrosse Players

BACKGROUND

Investigation into the effect of cumulative subconcussive head impacts has yielded various results in the literature, with many supporting a link to neurological deficits. Little research has been conducted on men's lacrosse and associated balance deficits from head impacts.

HYPOTHESES

(1) Athletes will commit more errors on the postseason Balance Error Scoring System (BESS) test. (2) There will be a positive correlation to change in BESS scores and head impact exposure data.

STUDY DESIGN

Prospective longitudinal study.

LEVEL OF EVIDENCE

Level 3.

METHODS

Thirty-four Division I men's lacrosse players (age, 19.59 ± 1.42 years) wore helmets instrumented with a sensor to collect head impact exposure data over the course of a competitive season. Players completed a BESS test at the start and end of the competitive season.

RESULTS

The number of errors from pre- to postseason increased during the double-leg stance on foam ( P < 0.001), tandem stance on foam ( P = 0.009), total number of errors on a firm surface ( P = 0.042), and total number of errors on a foam surface ( P = 0.007). There were significant correlations only between the total errors on a foam surface and linear acceleration ( P = 0.038, r = 0.36), head injury criteria ( P = 0.024, r = 0.39), and Gadd Severity Index scores ( P = 0.031, r = 0.37).

CONCLUSION

Changes in the total number of errors on a foam surface may be considered a sensitive measure to detect balance deficits associated with cumulative subconcussive head impacts sustained over the course of 1 lacrosse season, as measured by average linear acceleration, head injury criteria, and Gadd Severity Index scores. If there is microtrauma to the vestibular system due to repetitive subconcussive impacts, only an assessment that highly stresses the vestibular system may be able to detect these changes.

CLINICAL RELEVANCE

Cumulative subconcussive impacts may result in neurocognitive dysfunction, including balance deficits, which are associated with an increased risk for injury. The development of a strategy to reduce total number of head impacts may curb the associated sequelae. Incorporation of a modified BESS test, firm surface only, may not be recommended as it may not detect changes due to repetitive impacts over the course of a competitive season.

Reliability Testing of the Balance Error Scoring System in Children Between the Ages of 5 and 14

OBJECTIVE

Pediatric concussion is an extensive public health concern with a complex clinical presentation. Balance assessment has been well-studied in the adult population, but has been limited in children. We aimed to assess the reliability and minimum detectable change (MDC) of the Balance Error Scoring System (BESS) in healthy children.

DESIGN

This prospective observational study included 373 healthy children aged 5 to 14. Interrater reliability was assessed by having 4 assessors review videos of 50 random subjects distributed evenly by age and sex across the entire cohort. Intrarater reliability was performed by having assessors review videos of other assessors' live evaluations. Test-retest reliability was obtained by comparing BESS scores as recorded live at the 2 separate time points by the same rater.

SETTING

Local elementary and junior high schools.

PARTICIPANTS

Three hundred and seventy three healthy children between the ages of 5 and 14.

INTERVENTIONS

The BESS was performed on all children.

MAIN OUTCOME MEASURES

Intraclass Correlation Coefficients (ICCs) and MDC Scores.

RESULTS

The overall interrater ICC was determined to be 0.93 [95% confidence interval (CI), 0.79-0.97] and intrarater ICC was 0.96 (95% CI, 0.95-0.97) with individual intrarater ICCs ranging between 0.69 and 0.99. The test-retest reliability was 0.90 (95% CI, 0.88-0.92). The MDCs were 9.6, 4.6, and 7.3 points at the 95% CIs for interrater, intrarater, and test-retest comparisons, respectively. No learning effect was seen.

CONCLUSIONS

The BESS demonstrates excellent reliability in the pediatric population without evidence of a learning effect.

Validity and Reliability of the Vestibular/Ocular Motor Screening and Associations With Common Concussion Screening Tools

BACKGROUND

Sustaining a concussion commonly results in vestibular impairments that may be associated with balance deficits. To screen for vestibular impairments after a concussion, the Vestibular/Ocular Motor Screening (VOMS) tool was developed. The relationship between the VOMS and other concussion screening tools, such as the Balance Error Scoring System (BESS) and King-Devick (K-D), have not been explored.

HYPOTHESES

(1) VOMS would provide reliable results and not provoke symptoms in healthy adolescents and (2) VOMS test items would measure related aspects of vestibular function that are not measured through the BESS or K-D.

STUDY DESIGN

Cross-sectional, descriptive.

LEVEL OF EVIDENCE

Level 4.

METHODS

A total of 105 healthy adolescents (53 male, 52 female; mean age, 15.4 years) completed the VOMS, BESS, and K-D tests. A subsample of 21 adolescents (16 male, 5 female; mean age, 15.5 years) completed the VOMS twice.

RESULTS

The median total symptom score for all 7 VOMS items was 0 (0-5). The majority of the individual VOMS test items total symptom scores demonstrated a significant correlation with each other ( rs = 0.25-0.66, P < 0.02). The individual VOMS items did not demonstrate a significant relationship to the BESS or K-D. VOMS items demonstrated high agreement in total symptom scores between testing trials, with near point convergence (NPC) distance demonstrating an intraclass correlation coefficient (ICC) of 0.95 (95% CI, 0.89-0.98; P < 0.001). The MDC95 (minimal detectable change with 95 confidence) for NPC distance was 4 cm.

CONCLUSION

The VOMS did not provoke vestibular symptoms in healthy adolescents. The VOMS items measured unique aspects of vestibular function other than those measured by the BESS or K-D with good reliability.

CLINICAL RELEVANCE

Clinicians should consider implementing the VOMS as part of a comprehensive concussion assessment if vestibular impairment is suspected. If NPC distance is measured twice, a difference of >4 cm would be considered real change outside of measurement error.

Examining Recovery Trajectories After Sport-Related Concussion With a Multimodal Clinical Assessment Approach

BACKGROUND

Previous research estimates that the majority of athletes with sport-related concussion (SRC) will recover between 7 and 10 days after injury. This short temporal window of recovery is based predominately on symptom resolution and cognitive improvement and does not accurately reflect recent advances in the clinical assessment model.

OBJECTIVE

To characterize SRC recovery at 1-week postinjury time intervals on symptom, neurocognitive, and vestibular-oculomotor outcomes and to examine sex differences in SRC recovery time.

METHODS

A prospective, repeated-measures design was used to examine the temporal resolution of neurocognitive, symptom, and vestibular-oculomotor impairment in 66 subjects (age, 16.5 ± 1.9 years; range, 14-23 years; 64% male) with SRC.

RESULTS

Recovery time across all outcomes was between 21 and 28 days after SRC for most athletes. Symptoms demonstrated the greatest improvement in the first 2 weeks, although neurocognitive impairment lingered across various domains up to 28 days after SRC. Vestibular-oculomotor decrements also resolved between 1 and 3 weeks after injury. There were no sex differences in neurocognitive recovery. Male subjects were more likely to be asymptomatic by the fourth week and reported less vestibular-oculomotor impairment than female subjects at weeks 1 and 2.

CONCLUSION

When the recommended "comprehensive" approach is used for concussion assessment, recovery time for SRC is approximately 3 to 4 weeks, which is longer than the commonly reported 7 to 14 days. Sports medicine clinicians should use a variety of complementing assessment tools to capture the heterogeneity of SRC.

Balance function and sensory integration after mild traumatic brain injury

OBJECTIVE

This study examined the disparities in balance functions and sensory integration in patients with mild traumatic brain injuries (mTBIs) and healthy controls.

PARTICIPANTS

One hundred and seven patients with mTBI and 107 age- and sex-matched controls were recruaited for this study.

PRIMARY MEASURES

Symptoms of dizziness, balance functions and the ability to perform daily activities were assessed using the dizziness handicap inventory (DHI). This study also performed the postural-stability test and a modified clinical test of sensory integration by using the Biodex Stability System (BBS).

RESULTS

DHI scores (functional, emotional, physical and total self-reported scores) were substantially increased in patients following an mTBI compared with the scores of the controls (p < 0.000). The postural-stability test indices (anterior-posterior) (p = 0.045) and the sensory-integration test index (eyes-open-firm-surface index) (p = 0.006) were substantially lower in patients with mTBI than in the controls. However, indices of two other postural-stability test indices (overall and medial-lateral) and three other sensory-integration tests indices (eyes-closed-firm-surface, eyes-open-foam-surface and eyes-closed-foam-surface) measured for the mTBI group did not differ from those of the control group.

CONCLUSION

Activities of daily living, balance in postural stability and sensory integration were strongly impaired in patients with mTBI.

Reliability and concurrent validity of instrumented balance error scoring system using a portable force plate system

OBJECTIVES

The Balance Error Scoring System (BESS) is a commonly used test in adolescents and young adults. Affordability and portability of newer force plates has led to instrumentation of many clinical balance tests including the BESS. Despite the higher precision of force plate measures compared with clinical scoring, it is unclear if the instrumented BESS demonstrate concurrent validity and reliability when compared with the original BESS. The purpose of this study was to examine the reliability and concurrent validity of instrumented BESS testing using a commercially available force plate system.

METHODS

Thirty-six participants participated in the initial testing day (17 male/19 female, M = 15.9 years, SD = 1.5 years). The test-retest sample consisted of 26 participants who completed the same testing procedure after 1 week. For all testing sessions, participants performed the BESS while standing on a portable force plate system. Number of errors and sway velocity were obtained. Concurrent validity was established through correlation analysis examining the relationship between the original and the instrumented BESS scores. Reliability was established using Intraclass Correlation Coefficient (ICC3,1) computed for the instrumented and the original BESS.

RESULTS

A significant moderate relationship exists between the total scores of the original and the instrumented BESS (rs = 0.54, p = 0.001). Despite a range of reliability scores for the different conditions in the instrumented BESS (ICC3,1 = 0.19-0.61) and the clinically scored BESS (ICC3,1 = 0.13-0.71), the reliability score for the total test score was the same for the instrumented and the clinical test (ICC3,1 = 0.74).

CONCLUSION

Although the instrumented BESS may appear to demonstrate concurrent validity against the original BESS, instrumentation did not improve its reliability. Future research should examine if the instrumented BESS demonstrates validity against laboratory level force plates and if it is able to overcome the ceiling effect reported for the clinical BESS test.

Detection of concussion using cranial accelerometry

OBJECTIVE

To determine whether skull motion produced by pulsatile cerebral blood flow, as measured by cranial accelerometry, is altered during concussion.

DESIGN

In phase 1, to identify a specific pattern indicative of concussion, cranial accelerometry of subjects who sustained a concussion underwent analysis of waveforms, which was compared with accelerometry from subjects without a concussion (baseline). In phase 2, this concussion pattern was tested against prospectively acquired, blinded data.

SETTING

High school tackle football practice and game play.

PARTICIPANTS

Eighty-four football players.

INTERVENTIONS

Subjects had accelerometry measurements and concurrent 2-lead electrocardiograms. In players with a concussion, multiple sequential measurements were obtained. Sport Concussion Assessment Tool 2 was used to assist clinical determination of concussion.

MAIN OUTCOME MEASURES

Whether a characteristic waveform pattern of cranial accelerometry occurs in subjects with concussion.

RESULTS

Phase 1 demonstrated a consistent pattern correlated to concussion. Phase 2 found this pattern in 10 of 13 subjects with concussion (76.9% sensitivity). Seventy-nine of 82 baseline plus nine postseason (total = 91) recordings from nonconcussed subjects did not show the concussion pattern (87% specificity).

CONCLUSIONS

In subjects with concussion, we observed a unique pattern determined by cranial accelerometry. This may provide a method to noninvasively detect and longitudinally observe concussion.

CLINICAL RELEVANCE

There is no objective, real-time, noninvasive, and easily accessible measure for concussion. If accelerometry is validated, it could provide a critical diagnostic tool for sports medicine physicians.

Role of body-worn movement monitor technology for balance and gait rehabilitation

This perspective article will discuss the potential role of body-worn movement monitors for balance and gait assessment and treatment in rehabilitation. Recent advances in inexpensive, wireless sensor technology and smart devices are resulting in an explosion of miniature, portable sensors that can quickly and accurately quantify body motion. Practical and useful movement monitoring systems are now becoming available. It is critical that therapists understand the potential advantages and limitations of such emerging technology. One important advantage of obtaining objective measures of balance and gait from body-worn sensors is impairment-level metrics characterizing how and why functional performance of balance and gait activities are impaired. Therapy can then be focused on the specific physiological reasons for difficulty in walking or balancing during specific tasks. A second advantage of using technology to measure balance and gait behavior is the increased sensitivity of the balance and gait measures to document mild disability and change with rehabilitation. A third advantage of measuring movement, such as postural sway and gait characteristics, with body-worn sensors is the opportunity for immediate biofeedback provided to patients that can focus attention and enhance performance. In the future, body-worn sensors may allow therapists to perform telerehabilitation to monitor compliance with home exercise programs and the quality of their natural mobility in the community. Therapists need technological systems that are quick to use and provide actionable information and useful reports for their patients and referring physicians. Therapists should look for systems that provide measures that have been validated with respect to gold standard accuracy and to clinically relevant outcomes such as fall risk and severity of disability.

Assessing postural stability in the concussed athlete: what to do, what to expect, and when

Context:

Postural stability assessment is included as part of the diagnostic and monitoring process for sports-related concussions. Particularly, the relatively simple Balance Error Scoring System (BESS) and more sophisticated force plate measures like the Sensory Organization Test (SOT) are suggested.

Evidence Acquisition:

Relevant studies were identified via the following electronic databases: PubMed, MEDLINE, EMBASE, Web of Science, ScienceDirect, and CINAHL (1980 to July 2013). Inclusion was based on the evaluation of postural sway or balance in concussed athletes of any age or sex and investigating the reliability or validity of the included tests.

Study Design:

Clinical review.

Level of Evidence:

Level 4

Results:

Both the SOT and the BESS show moderate reliability, but a learning effect due to repetitive testing needs to be considered. Both tests indicate that postural stability returns to baseline by day 3 to 5 in most concussed athletes. While the BESS is a simple and valid method, it is sensitive to subjectivity in scoring and the learning effect. The SOT is very sensitive to even subtle changes in postural sway, and thus, more accurate than the BESS; however, it is a rather expensive method of balance testing.

Conclusion:

Both tests serve the purpose of monitoring balance performance in the concussed athlete; however, neither may serve as a stand-alone diagnostic or monitoring tool.

Strength of Recommendation Taxonomy:

B

Effect of teaching with or without mirror on balance in young female ballet students

Background

In literature there is a general consensus that the use of the mirror improves proprioception. During rehabilitation the mirror is an important instrument to improve stability. In some sports, such as dancing, mirrors are widely used during training. The purpose of this study is to evaluate the effectiveness of the use of a mirror on balance in young dancers. Sixty-four young dancers (ranging from 9–10 years) were included in this study. Thirty-two attending lessons with a mirror (mirror- group) were compared to 32 young dancers that attended the same lessons without a mirror (non-mirror group). Balance was evaluated by BESS (Balance Error Scoring System), which consists of three stances (double limb, single limb, and tandem) on two surfaces (firm and foam). The errors were assessed at each stance and summed to create the two subtotal scores (firm and foam surface) and the final total score (BESS). The BESS was performed at recruitment (T0) and after 6 months of dance lessons (T1).

Results

The repeated measures ANOVA analysis showed that for the BESS total score there is a difference due to the time (F = 3.86; p < 0.05). No other differences due to the group or to the time of measurement were found (p > 0.05). The analysis of the multiple regression model showed the influence of the values at T0 for every BESS items and the dominance of limb for stability on an unstable surface standing on one or two legs.

Conclusions

These preliminary results suggest that the use of a mirror in a ballet classroom does not improve balance acquisition of the dancer. On the other hand, improvement found after 6 months confirms that at the age of the dancers studied motor skills and balance can easily be trained and improved.

Instrumenting the balance error scoring system for use with patients reporting persistent balance problems after mild traumatic brain injury

OBJECTIVE

To determine whether alterations to the Balance Error Scoring System (BESS), such as modified conditions and/or instrumentation, would improve the ability to correctly classify traumatic brain injury (TBI) status in patients with mild TBI with persistent self-reported balance complaints.

DESIGN

Cross-sectional study.

SETTING

Outpatient clinic.

PARTICIPANTS

Subjects (n=13; age, 16.3±2y) with a recent history of concussion (mild TBI group) and demographically matched control subjects (n=13; age, 16.7±2y; control group).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Outcome measures included the BESS, modified BESS, instrumented BESS, and instrumented modified BESS. All subjects were tested on the noninstrumented BESS and modified BESS and were scored by visual observation of instability in 6 and 3 stance conditions, respectively. Instrumentation of these 2 tests used 1 inertial sensor with an accelerometer and gyroscope to quantify bidirectional body sway.

RESULTS

Scores from the BESS and the modified BESS tests were similar between groups. However, results from the instrumented measures using the inertial sensor were significantly different between groups. The instrumented modified BESS had superior diagnostic classification and the largest area under the curve when compared with the other balance measures.

CONCLUSIONS

A concussion may disrupt the sensory processing required for optimal postural control, which was measured by sway during quiet stance. These results suggest that the use of portable inertial sensors may be useful in the move toward more objective and sensitive measures of balance control postconcussion, but more work is needed to increase sensitivity.

Recovery of static stability following a concussion

The purpose of this study was to use centre of pressure (COP) measurements to determine if static balance deficits had recovered when concussed athletes were cleared to return to play. Nine concussed varsity football players were matched with nine teammates who served as controls. Static balance in the anterior-posterior (A/P) and medial-lateral (M/L) directions was assessed during quiet stance with eyes open and eyes closed. Results showed that concussed football players displayed greater A/P COP displacements in the acute phase, which recovered by RTP; however, COP velocity remained elevated compared to controls even at RTP, particularly in the A/P direction. This balance control deficit in the A/P direction may suggest vestibular impairment, likely due to poor sensorimotor integration of the lateral vestibulospinal tract. The observed persistence of balance control deficits in concussed football players at RTP are usually undetected by traditional assessments because the current study used higher-order COP analysis. Future RTP balance measures may want to incorporate higher-order measures of balance.