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

Instrumented Balance Error Scoring System in Children and Adolescents-A Cross Sectional Study

Background: The Balance Error Scoring System (BESS) is a commonly used method for clinically evaluating balance after traumatic brain injury. The utilization of force plates, characterized by their cost-effectiveness and portability, facilitates the integration of instrumentation into the BESS protocol. Despite the enhanced precision associated with instrumented measures, there remains a need to determine the clinical significance and feasibility of such measures within pediatric cohorts. Objective: To report a comprehensive set of posturographic measures obtained during instrumented BESS and to examine the concurrent validity, reliability, and feasibility of instrumented BESS in the pediatric point of care setting. Methods: Thirty-seven participants (18 female; aged 13.32 ± 3.31 years) performed BESS while standing on a force plate to simultaneously compute stabilometric measures (instrumented BESS). Ellipse area (EA), path length (PL), and sway velocity (VM) were obtained for each of the six BESS positions and compared with the respective BESS scores. Additionally, the effects of sex and age were explored. A second BESS repetition was performed to evaluate the test-retest reliability. Feedback questionnaires were handed out after testing to evaluate the feasibility of the proposed protocol. Results: The BESS total score was 20.81 ± 6.28. While there was no statistically significant age or sex dependency in the BESS results, instrumented posturography demonstrated an age dependency in EA, VM, and PL. The one-leg stance on a soft surface resulted in the highest BESS score (8.38 ± 1.76), EA (218.78 cm2 ± 168.65), PL (4386.91 mm ± 1859.00), and VM (21.93 mm/s ± 9.29). The Spearman's coefficient displayed moderate to high correlations between the EA (rs = 0.429-0.770, p = 0.001-0.009), PL (rs = 0.451-0.809, p = 0.001-0.006), and VM (rs = 0.451-0.809, p = 0.001-0.006) when compared with the BESS scores for all testing positions, except for the one-leg stance on a soft surface. The BESS total score significantly correlated during the first and second repetition (rs = 0.734, p ≤ 0.001), as did errors during the different testing positions (rs = 0.489-0.799, p ≤ 0.001-0.002), except during the two-legged stance on a soft surface. VM and PL correlated significantly in all testing positions (rs = 0.465-0.675, p ≤ 0.001-0.004; (rs = 0.465-0.675, p ≤ 0.001-0.004), as did EA for all positions except for the two-legged stance on a soft surface (rs = 0.392-0.581, p ≤ 0.001-0.016). A total of 92% of participants stated that the instructions for the testing procedure were very well-explained, while 78% of participants enjoyed the balance testing, and 61% of participants could not decide whether the testing was easy or hard to perform. Conclusions: Instrumented posturography may complement clinical assessment in investigating postural control in children and adolescents. While the BESS score only allows for the consideration of a total score approximating postural control, instrumented posturography offers several parameters representing the responsiveness and magnitude of body sway as well as a more differentiated analysis of movement trajectory. Concise instrumented posturography protocols should be developed to augment neuropediatric assessments in cases where a deficiency in postural control is suspected, potentially stemming from disruptions in the processing of visual, proprioceptive, and/or vestibular information.

Validity and Reliability of Methods to Assess Movement Deficiencies Following Concussion: A COSMIN Systematic Review

BACKGROUND

There is an increased risk of subsequent concussion and musculoskeletal injury upon return to play following a sports-related concussion. Whilst there are numerous assessments available for clinicians for diagnosis and during return to play following concussion, many may lack the ability to detect these subclinical changes in function. Currently, there is no consensus or collated sources on the reliability, validity and feasibility of these assessments, which makes it difficult for clinicians and practitioners to select the most appropriate assessment for their needs.

OBJECTIVES

This systematic review aims to (1) consolidate the reliability and validity of motor function assessments across the time course of concussion management and (2) summarise their feasibility for clinicians and other end-users.

METHODS

A systematic search of five databases was conducted. Eligible studies were: (1) original research; (2) full-text English language; (3) peer-reviewed with level III evidence or higher; (4) assessed the validity of lower-limb motor assessments used to diagnose or determine readiness for athletes or military personnel who had sustained a concussion or; (5) assessed the test-retest reliability of lower-limb motor assessments used for concussion management amongst healthy athletes. Acceptable lower-limb motor assessments were dichotomised into instrumented and non-instrumented and then classified into static (stable around a fixed point), dynamic (movement around a fixed point), gait, and other categories. Each study was assessed using the COSMIN checklist to establish methodological and measurement quality.

RESULTS

A total of 1270 records were identified, with 637 duplicates removed. Titles and abstracts of 633 records were analysed, with 158 being retained for full-text review. A total of 67 records were included in this review; 37 records assessed reliability, and 35 records assessed the validity of lower-limb motor assessments. There were 42 different assessments included in the review, with 43% being non-instrumented, subjective assessments. Consistent evidence supported the use of instrumented assessments over non-instrumented, with gait-based assessments demonstrating sufficient reliability and validity compared to static or dynamic assessments.

CONCLUSION

These findings suggest that instrumented, gait-based assessments should be prioritised over static or dynamic balance assessments. The use of laboratory equipment (i.e. 3D motion capture, pressure sensitive walkways) on average exhibited sufficient reliability and validity, yet demonstrate poor feasibility. Further high-quality studies evaluating the reliability and validity of more readily available devices (i.e. inertial measurement units) are needed to fill the gap in current concussion management protocols. Practitioners can use this resource to understand the accuracy and precision of the assessments they have at their disposal to make informed decisions regarding the management of concussion.

TRAIL REGISTRATION

This systematic review was registered on PROSPERO (reg no. CRD42021256298).

Test-Retest reliability and preliminary reliable change estimates for Sway Balance tests administered remotely in community-dwelling adults

OBJECTIVE

Impaired balance and postural stability can occur with advanced age, following traumatic brain injury, in association with neurological disorders and diseases, and as the result of acute or chronic orthopedic problems. The remote assessment of balance and postural stability could be of value in clinical practice and research. We examined the test-retest reliability and reliable change estimates for Sway Balance Mobile Application tests (Sway Medical, Tulsa OK, USA) administered remotely from the participant's home.

METHOD

Primarily young, healthy community-dwelling adults completed Sway Balance Mobile Application tests remotely on their personal mobile devices once per week for three consecutive weeks while being supervised with a video-based virtual connection. Sway Balance tests include five stances (i.e., feet together, tandem right foot forward, tandem left foot forward, single leg right foot, single leg left foot), which are averaged to compute a Sway Balance composite score from 0 to 100, with higher scores indicating better postural stability. We examined test-retest reliability (measured with intraclass correlation coefficients, ICCs) and preliminary reliable change estimates for 70%, 80%, and 90% confidence intervals.

RESULTS

Participants included 55 healthy adults (ages = 26.7 ± 9.9 years, interquartile range = 20-30, range = 18-58; 38 [69%] women). Test-retest reliability for the Sway Balance composite score across three weeks was.88. Test-retest reliability for individual stances ranged from 62 to 83 (all ps < 0.001). At the 80% confidence interval, preliminary reliable changes estimates were 9 points for the Sway Balance composite score.

CONCLUSIONS

For a remote administration, test-retest reliability was moderate-to-good for all Sway Balance stances, as well as for the Sway Balance composite score. Reliable change estimates may allow clinicians to determine whether an improvement or decline in performance is greater than the expected improvement or decline due to measurement error in young adults.

Acute Impact of Proprioceptive Exercise on Proprioception and Balance in Athletes

This study aimed to compare the acute effect of a proprioceptive exercise session and a non-specific exercise session on knee position sense, and the static and dynamic balance of athletes. Sixty male athletes (19.4 ± 1.2 years) participated in a within-subjects repeated-measures study. Knee position sense in closed kinetic chain, and static (BESS test) and dynamic balance (Y-balance test) were measured before and after two exercise sessions, consisting of 10 min of non-specific exercise in a cycle-ergometer or proprioceptive exercise with an unstable platform. Overall, both exercise sessions significantly improved knee position sense, BESS score, and YBT composite score, and no differences were detected between proprioceptive and non-specific sessions (knee position sense, −6.9 ± 65.2% vs. −11.5 ± 75.0%, p = 0.680; BESS, −19.3 ± 47.7% vs. −29.03 ± 23.5%, p = 0.121; YBT, 2.6 ± 2.7% vs. 2.2 ± 2.2%, p = 0.305). Twenty athletes did not improve knee position sense after the exercise session (non-responders). When analyzing only the exercise responders, both sessions improved knee position sense, but the improvement was greater after the proprioceptive exercise session (56.4 ± 25.6% vs. 43.8 ± 18.9%, p = 0.023). In conclusion, a single proprioceptive, as well as non-specific, exercise session increased knee position sense and balance. The proprioceptive exercise seems to be more effective in improving joint position sense when considering only athletes who respond to the intervention.

Reliability and Minimal Detectable Change for a Smartphone-Based Motor-Cognitive Assessment: Implications for Concussion Management

Our purpose was to investigate the reliability and minimal detectable change characteristics of a smartphone-based assessment of single- and dual-task gait and cognitive performance. Uninjured adolescent athletes (n = 17; mean age = 16.6, SD = 1.3 y; 47% female) completed assessments initially and again 4 weeks later. The authors collected data via an automated smartphone-based application while participants completed a series of tasks under (1) single-task cognitive, (2) single-task gait, and (3) dual-task cognitive-gait conditions. The cognitive task was a series of continuous auditory Stroop cues. Average gait speed was consistent between testing sessions in single-task (0.98, SD = 0.21 vs 0.96, SD = 0.19 m/s; P = .60; r = .89) and dual-task (0.92, SD = 0.22 vs 0.89, SD = 0.22 m/s; P = .37; r = .88) conditions. Response accuracy was moderately consistent between assessments in single-task standing (82.3% accurate, SD = 17.9% vs 84.6% accurate, SD = 20.1%; P = .64; r = .52) and dual-task gait (89.4% accurate, SD = 15.9% vs 85.8% accurate, SD = 20.2%; P = .23; r = .81) conditions. Our results indicate automated motor-cognitive dual-task outcomes obtained within a smartphone-based assessment are consistent across a 1-month period. Further research is required to understand how this assessment performs in the setting of sport-related concussion. Given the relative reliability of values obtained, a smartphone-based evaluation may be considered for use to evaluate changes across time among adolescents, postconcussion.

Choose your words wisely: Optimizing impacts on standardized performance testing

BACKGROUND

The OPTIMAL theory of motor learning identifies motivational (enhanced expectancies, EE, and autonomy support, AS) and attentional (an external attentional focus, EF) factors that affect motor performance and learning [1]. One implication of this theory is that standardized clinical and laboratory assessments of physical capacity and motor performance that do not incorporate optimizing conditions may underestimate true maximal capabilities. The influence of "optimized" conditions on a clinical-applied test of balance control was examined with healthy participants. Given the motor performance benefits of optimized conditions predicted by the OPTIMAL theory, it was hypothesized that providing participants with information that induced EE, provided them with AS, and promoted their use of EF would reduce balance errors and postural sway.

METHODS

We used as an exemplar assessment, the Balance Error Scoring System (BESS), and center-of-pressure (COP) velocity measurements of postural sway. Participants performed under two different conditions, separated by two days: an optimized (EE, AS, and EF) condition and a control ("neutral") condition, with sample-wide order counterbalancing. In each condition, participants performed three stances (double-leg, single-leg, and tandem) on two support surfaces (firm and foam). Stance order was participant-determined in the optimized condition and, for the control condition, yoked to a participant in the optimized condition.

RESULTS

Participants committed fewer balance errors in the optimized condition than in the control condition (p < .001) and their resultant COP velocity in the optimized condition was lower than that in the control condition (p = .004). BESS scores were correlated with resultant COP velocity (r = .593, p < .001).

SIGNIFICANCE

Our results demonstrated the impact of implementing optimized, as opposed to "neutral" control, conditions for better insight into balance capabilities in normal and challenging situations. Practitioners' roles in mediating test situations and using subtle wording to promote optimized performance may have consequential impacts on motor assessment outcomes.

Validity of an Automated Balance Error Scoring System

The Balance Error Scoring System (BESS) is a human-scored, field-based balance test used in cases of suspected concussion. Recently developed instrumented alternatives to human scoring carry substantial advantages over traditional testing, but thus far report relatively abstract outcomes which may not be useful to clinicians or coaches. In contrast, the Automated Assessment of Postural Stability (AAPS) is a computerized system that tabulates error events in accordance with the original description of the BESS. This study compared AAPS and human-based BESS scores. Twenty-five healthy adults performed the modified BESS. Tests were scored twice each by human raters (3) and the computerized system. Interrater (between-human) and inter-method (AAPS vs. human) agreement (ICC_(2,1)) were calculated alongside Bland-Altman limits of agreement (LOA). Interrater analyses were significant (p<0.005) and demonstrated good to excellent agreement. Inter-method agreement analyses were significant (p<0.005), with agreement ranging from poor to excellent. Computerized scores were equivalent across rating occasions. LOA ranges for AAPS vs. the Human Average exceeded the average LOA ranges between human raters. Coaches and clinicians may consider a system such as AAPS to automate balance testing while maintaining the familiarity of human-based scoring, although scores should not yet be considered interchangeable with those of a human rater.

An Objective Balance Error Scoring System for Sideline Concussion Evaluation Using Duplex Kinect Sensors

Sports-related concussion is a common sports injury that might induce potential long-term consequences without early diagnosis and intervention in the field. However, there are few options of such sensor systems available. The aim of the study is to propose and validate an automated concussion administration and scoring approach, which is objective, affordable and capable of detecting all balance errors required by the balance error scoring system (BESS) protocol in the field condition. Our approach is first to capture human body skeleton positions using two Microsoft Kinect sensors in the proposed configuration and merge the data by a custom-made algorithm to remove the self-occlusion of limbs. The standing balance errors according to BESS protocol were further measured and accessed automatically by the proposed algorithm. Simultaneously, the BESS test was filmed for scoring by an experienced rater. Two results were compared using Pearson coefficient r, obtaining an excellent consistency (r = 0.93, p < 0.05). In addition, BESS test–retest was performed after seven days and compared using intraclass correlation coefficients (ICC), showing a good test–retest reliability (ICC = 0.81, p < 0.01). The proposed approach could be an alternative of objective tools to assess postural stability for sideline sports concussion diagnosis.

The Automated Assessment of Postural Stability: Balance Detection Algorithm

Impaired balance is a common indicator of mild traumatic brain injury, concussion and musculoskeletal injury. Given the clinical relevance of such injuries, especially in military settings, it is paramount to develop more accurate and reliable on-field evaluation tools. This work presents the design and implementation of the automated assessment of postural stability (AAPS) system, for on-field evaluations following concussion. The AAPS is a computer system, based on inexpensive off-the-shelf components and custom software, that aims to automatically and reliably evaluate balance deficits, by replicating a known on-field clinical test, namely, the Balance Error Scoring System (BESS). The AAPS main innovation is its balance error detection algorithm that has been designed to acquire data from a Microsoft Kinect^® sensor and convert them into clinically-relevant BESS scores, using the same detection criteria defined by the original BESS test. In order to assess the AAPS balance evaluation capability, a total of 15 healthy subjects (7 male, 8 female) were required to perform the BESS test, while simultaneously being tracked by a Kinect 2.0 sensor and a professional-grade motion capture system (Qualisys AB, Gothenburg, Sweden). High definition videos with BESS trials were scored off-line by three experienced observers for reference scores. AAPS performance was assessed by comparing the AAPS automated scores to those derived by three experienced observers. Our results show that the AAPS error detection algorithm presented here can accurately and precisely detect balance deficits with performance levels that are comparable to those of experienced medical personnel. Specifically, agreement levels between the AAPS algorithm and the human average BESS scores ranging between 87.9% (single-leg on foam) and 99.8% (double-leg on firm ground) were detected. Moreover, statistically significant differences in balance scores were not detected by an ANOVA test with alpha equal to 0.05. Despite some level of disagreement between human and AAPS-generated scores, the use of an automated system yields important advantages over currently available human-based alternatives. These results underscore the value of using the AAPS, that can be quickly deployed in the field and/or in outdoor settings with minimal set-up time. Finally, the AAPS can record multiple error types and their time course with extremely high temporal resolution. These features are not achievable by humans, who cannot keep track of multiple balance errors with such a high resolution. Together, these results suggest that computerized BESS calculation may provide more accurate and consistent measures of balance than those derived from human experts.

Performance of high school male athletes on the Functional Movement Screen™

OBJECTIVES

(1) Describe the performance of the Functional Movement Screen™ (FMS™) by reporting the proportion of adolescents with a score of ≤14 and the frequency of asymmetries in a cross-sectional sample; (2) explore associations between FMS™ to age and body mass, and explore the construct validity of the FMS™ against common postural stability measures; (3) examine the inter-rater and test-retest reliability of the FMS™ in adolescents.

DESIGN

Cross-sectional.

SETTING

Field-setting.

PARTICIPANTS

94 male high-school athletes.

MAIN OUTCOME MEASURE

The FMS™, Y-Balance Test (YBT) and Balance Error Scoring System (BESS).

RESULTS

The median FMS™ composite score was 16 (9-21), 33% of participants scored below the suggested injury risk cutoff composite score of ≤14, and 62.8% had at least one asymmetry. No relationship was observed between the FMS™ to common static/dynamic balance tests. The inter-rater reliability of the FMS™ composite score suggested good reliability (ICC = 0.88, CI 95%:0.77, 0.94) and test-retest reliability for FMS™ composite scores was good with ICC = 0.83 (CI 95%:0.56, 0.95).

CONCLUSIONS

FMS™ results should be interpreted cautiously with attention to the asymmetries identified during the screen, regardless of composite score. The lack of relationship between the FMS™ and other balance measures supports the notion that multiple screening tests should be used in order to provide a comprehensive picture of the adolescent athlete.

A prospective investigation of changes in the sensorimotor system following sports concussion. An exploratory study

BACKGROUND

Sports concussion is a risk for players involved in high impact, collision sports. Post-concussion, the majority of symptoms subside within 7-10 days, but can persist in 10-20% of athletes. Understanding the effects of sports concussion on sensorimotor systems could inform physiotherapy treatment.

OBJECTIVE

To explore changes in sensorimotor function in the acute phase following sports concussion.

DESIGN

Prospective cohort study.

METHODS

Fifty-four players from elite rugby union and league teams were assessed at the start of the playing season. Players who sustained a concussion were assessed three to five days later. Measures included assessments of balance (sway velocity), vestibular system function (vestibular ocular reflex gain; right-left asymmetry), cervical proprioception (joint position error) and trunk muscle size and function.

RESULTS

During the playing season, 14 post-concussion assessments were performed within 3-5 days of injury. Significantly decreased sway velocity and increased size/contraction of trunk muscles, were identified. Whilst not significant overall, large inter-individual variation of test results for cervical proprioception and the vestibular system was observed.

LIMITATIONS

The number of players who sustained a concussion was not large, but numbers were comparable with other studies in this field. There was missing baseline data for vestibular and cervical proprioception testing for some players.

CONCLUSIONS

Preliminary findings post-concussion suggest an altered balance strategy and trunk muscle control with splinting/over-holding requiring consideration as part of the development of appropriate physiotherapy management strategies.

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.

Evaluation of postural stability in youth athletes: the relationship between two rating systems

OBJECTIVES

The Balance Error Scoring System (BESS) has been documented as a useful way to evaluate postural control following sport-related concussions sustained by youth athletes. However, limitations have been reported with its use due to the reliance on visual observation as the primary measurement outcome. The primary purpose of this study was to examine the correlation between the modified BESS (mBESS) as rated by a clinician and a simultaneous analysis performed by an integrated video-force plate system. The secondary purpose was to assess if a history of prior concussion affected postural control.

METHODS

A group of healthy youth athletes (n = 398; mean age 13.7 ± 2.4 years) completed the mBESS while simultaneously undergoing an integrated video-force plate evaluation to measure postural stability. Spearman rank-order correlations were used to determine the strength of correlation between the 2 rating systems. In addition, performance on the mBESS between those with and without a history of concussion was compared using univariate ANCOVAs.

RESULTS

A moderately high correlation was found during single-leg stance (ρ = -0.64, p < .001), while a weak correlation was found during tandem stance (ρ = -0.30, p < .001). No postural control differences were found between groups with and without a concussion history.

CONCLUSION

The video-force plate rating system correlates well with the clinician rating during the single-leg stance of the mBESS, but not during double-leg or tandem stances. A history of concussion did not affect mBESS scores.