Baseline Concussion Clinical Measures Are Related to Sensory Organization and Balance

Normative Values for the Head Shake Sensory Organization Test in an Active Duty Military Cohort

INTRODUCTION

The Head Shake Sensory Organization Test (HS-SOT) assesses postural stability while the head is moving and may also identify deficits in attention associated with the dual task conditions of moving the head at a specified speed while maintaining balance. Normative values for the HS-SOT have not been established in a healthy military population or other highly trained populations such as athletes. Establishing normative values in a military population will enable clinicians to compare the scores of patients with medical conditions that affect postural stability and sensory integration such as concussion or traumatic brain injury, vestibular dysfunction, or migraine to those of a healthy population to determine a need for intervention and for return to duty considerations. The purposes of this cross-sectional study were to establish normative values for the HS-SOT within the military population, to determine whether HS-SOT scores differed between men and women or among age groups, and to determine whether HS-SOT scores differed from scores on similar conditions of the Sensory Organization Test (SOT).

MATERIALS AND METHODS

Active duty service members (n = 237, 54 female) at Joint Base Lewis-McChord, Washington, Fort Campbell, Kentucky, and the National Capitol Region (Washington, D.C, Maryland, and Virginia) completed the SOT and HS-SOT on the NeuroCom® Balance Master™. Parametric and non-parametric comparisons were analyzed for the equilibrium scores for the SOT and HS-SOT conditions 2 (SOT-2, HS-SOT-2, respectively) and 5 (SOT-5, HS-SOT-5, respectively) and the equilibrium score ratios (ESRs) for HS-SOT-2 and HS-SOT-5 for the total sample, men and women, and age group categories (18-26 years, 27-35 years, and 36-45 years).

RESULTS

There were no differences in HS-SOT-2 or HS-SOT-5 equilibrium ratio scores between men (0.99 ±.029 and 0.83 ±0.25, respectively) and women (1.00 ±0.03 and 0.81 ±0.21, respectively). There were no differences in the SOT-2 equilibrium scores (F = 2.29, P = 0.10) or SOT-5 equilibrium scores (Kruskal-Wallis H = 3.26, P = 0.20) among the different age groups. SOT-2 equilibrium scores were higher than the HS-SOT-2 equilibrium scores (Z = -4.10, P < 0.001). SOT-5 equilibrium scores were also higher than HS-SOT-5 equilibrium scores (Z = -12.22, P < 0.001), and the HS-SOT-2 and HS-SOT-5 equilibrium scores differed from each other (Z = -13.26, P < 0.001).

CONCLUSIONS

This study established normative values for the HS-SOT in a military population. Equilibrium scores did not differ between men and women or among age groups, suggesting that these values can be used as reference points for most service members. Postural stability was found to be significantly challenged during head motion, indicating the HS-SOT is a valuable tool for identifying subtle impairments in postural stability. These findings have important implications for early detection and intervention in individuals with medical conditions affecting balance, particularly concussions or vestibular disorders.

The effects of augmenting traditional rehabilitation with audio biofeedback in people with persistent imbalance following mild traumatic brain injury

Complaints of non-resolving imbalance are common in individuals with chronic mild traumatic brain injury (mTBI). Vestibular rehabilitation therapy may be beneficial for this population. Additionally, wearable sensors can enable biofeedback, specifically audio biofeedback (ABF), and aid in retraining balance control mechanisms in people with balance impairments. In this study, we described the effectiveness of vestibular rehabilitation therapy with and without ABF to improve balance in people with chronic mTBI. Participants (n = 31; females = 22; mean age = 40.9 ± 11 y) with chronic (>3 months) mTBI symptoms of self-reported imbalance were randomized into vestibular rehabilitation with ABF (n = 16) or without ABF (n = 15). The intervention was a standard vestibular rehabilitation, with or without ABF, for 45 min biweekly for 6 weeks. The ABF intervention involved a smartphone that provided auditory feedback when postural sway was outside of predetermined equilibrium parameters. Participant's completed the Post-Concussion Symptom Scale (PCSS). Balance was assessed with the sensory organization test (SOT) and the Central Sensorimotor Integration test which measured sensory weighting, motor activation, and time delay with sway evoked by surface and/or visual surround tilts. Effect sizes (Hedge's G) were calculated on the change between pre-and post-rehabilitation scores. Both groups demonstrated similar medium effect-sized decreases in PCSS and large increases in SOT composite scores after rehabilitation. Effect sizes were minimal for increasing sensory weighting for both groups. The with ABF group showed a trend of larger effect sizes in increasing motor activation (with ABF = 0.75, without ABF = 0.22) and in decreasing time delay (with ABF = −0.77, without ABF = −0.52) relative to the without ABF group. Current clinical practice focuses primarily on sensory weighting. However, the evaluation and utilization of motor activation factors in vestibular rehabilitation, potentially with ABF, may provide a more complete assessment of recovery and improve outcomes.

The University of Kansas Health System Outpatient Clinical Concussion Comprehensive Protocol: An Interdisciplinary Approach

Objective:

The concussion team at The University of Kansas Health System outpatient rehabilitation spine center is comprised of experienced multi-disciplinary experts including physical therapists and a speech language pathologist. The team set forth with a purpose of creating and organizing an internal physical therapy clinical recommendation protocol for initial evaluations and subsequent treatments for the concussed patient. The aim of this paper is to share these recommendation protocols with other therapy teams and provide a foundational layout for treating the patient with post-concussion symptoms in an outpatient physical therapy clinical setting.

Study design:

Clinical recommendation protocol provides guidance for patients ages 10+ from initial evaluation through discharge with emphasis on evidence-based research in the areas of: oculomotor, cervical, vestibular, post-concussion migraine influence, mood disorders(such as anxiety and depression), exertion, and cognitive communicative dysfunction.

Results:

Finding a written, comprehensive clinical resource protocol for post-concussion outpatient evaluation(s) and treatment strategies can be difficult. This document serves as a resource for other outpatient concussion rehabilitation clinics, providing rationale, and objective measurement tools, for assessing and treating concussion patients. To the authors’ knowledge, no other research has produced a practical, efficient evaluation tool to be utilized at bed side, condensing evidence-based research into an easy-to-use form.

Conclusion:

The University of Kansas Health System outpatient concussion rehabilitation center developed clinical recommendation protocols for concussion care. The intent was to standardize assessment and treatment for concussion patients and to share these objective measurement tools and procedures, focused on a team approach of concussion providers, as a clinical outline for both the novice and seasoned clinician specializing in the field of concussion work in an outpatient rehabilitation setting.

Balance and Cognition in Male Collegiate Lacrosse Players

Concussion screening among collegiate lacrosse athletes is a major safety priority. Although attention has been directed at concussion management following injury, less is known about the association between cognition and balance during preseason screening. The purpose of the study was to assess the relationship between balance and neurocognition among collegiate male lacrosse players and to examine predictive determinants of postural stability. Participants included a convenience sample of 49 male collegiate Division 3 lacrosse players who completed a demographic survey and performed the immediate postconcussion test (ImPACT) and instrumented Sensory Organization Test (SOT). There was a significant association between balance SOT performance and both verbal memory (r = .59, p < .01) and visual motor speed scores (r = .43, p < .05). Significant correlations between verbal memory and SOT Conditions 2, 5, and 6 were also noted (all p < .05). Verbal memory predicted 33% of the variance in the SOT composite balance score (p < .001). Our results indicate a significant relationship exists between postural stability and both verbal memory and visual processing speed among collegiate male lacrosse players and supports vestibulocortical associations. Findings warrant ongoing performance and executive function tracking and can serve as a conduit for integrated sensorimotor and dual-task training.

Change in Balance Performance Predicts Neurocognitive Dysfunction and Symptom Endorsement in Concussed College Athletes

OBJECTIVE

Following concussion, there is an array of sequelae including symptom burden, neurocognitive dysfunction, and balance impairment. However, the magnitude of change in balance performance has yet to be explored fully regarding its relationship with neurocognitive functioning or symptom endorsement. The present study hypothesized that the magnitude of change in balance performance from baseline to post-trauma would have unique predictive power in identifying acute clinical outcomes.

METHOD

Sixty-eight college athletes completed annual preparticipation baseline testing and were later diagnosed with a concussion.

RESULTS

Linear regressions determined that the magnitude of change in balance performance was a better predictor of neurocognitive dysfunction and endorsement of "balance problems" than post-trauma balance performance alone.

CONCLUSIONS

These findings highlight the importance of incorporating balance measurements during preparticipation baseline assessment.

Stroboscopic Vision as a Dynamic Sensory Reweighting Alternative to the Sensory Organization Test

CONTEXT

The sensory organization test (SOT) is a standard for quantifying sensory dependence via sway-referenced conditions (sway-referenced support and sway-referenced vision [SRV]). However, the SOT is limited to expensive equipment. Thus, a practical version of the SOT is more commonly employed-the clinical test for sensory integration in balance; however, it fails to induce postural instability to the level of SRV.

OBJECTIVE

Determine if Stroboscopic vision (SV), characterized by intermittent visual blocking, may provide an alternative to the SRV for assessing postural stability.

DESIGN

Descriptive laboratory study.

SETTING

Research laboratory.

PARTICIPANTS

Eighteen participants (9 males, 9 females; age = 22.1 [2.1] y, height = 169.8 [8.5] cm, weight = 66.5 [10.6] kg).

INTERVENTION

Participants completed the SOT conditions, and then repeated SOT conditions 2 and 5 with SV created by specialized eyewear.

MAIN OUTCOME MEASURES

A repeated-measures analysis of variance was completed on the time-to-boundary metrics of center-of-pressure excursion in the anteroposterior and mediolateral directions in order to determine the difference between the full-vision, SV, and SRV conditions.

RESULTS

Postural stability with either SRV or SV was significantly worse than with full vision (P < .05), with no significant difference between SV and SRV (P > .05). Limits of agreement analysis revealed similar effects of SV and SRV except for unstable surface mediolateral time-to-boundary.

CONCLUSIONS

In general, SV was found to induce a degree of postural instability similar to that induced by SRV, indicating that SV could be a portable and relatively inexpensive alternative for the assessment of sensory dependence and reweighting.

Relationship Between the King-Devick Test and Commonly Used Concussion Tests at Baseline

CONTEXT

Comprehensive assessments are recommended to evaluate sport-related concussion (SRC). The degree to which the King-Devick (KD) test adds novel information to an SRC evaluation is unknown.

OBJECTIVE

To describe relationships at baseline among the KD and other SRC assessments and explore whether the KD provides unique information to a multimodal baseline concussion assessment.

DESIGN

Cross-sectional study.

SETTING

Five National Collegiate Athletic Association institutions participating in the Concussion Assessment, Research and Education (CARE) Consortium.

PATIENTS OR OTHER PARTICIPANTS

National Collegiate Athletic Association student-athletes (N = 2258, age = 20 ± 1.5 years, 53.0% male, 68.9% white) in 11 men's and 13 women's sports.

MAIN OUTCOME MEASURE(S)

Participants completed baseline assessments on the KD and (1) the Symptom Inventory of the Sport Concussion Assessment Tool-3rd edition, (2) the Brief Symptom Inventory-18, (3) the Balance Error Scoring System, (4) the Standardized Assessment of Concussion (SAC), (5) the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) test battery, and (6) the Vestibular/Ocular Motor Screening tool during their first year in CARE. Correlation coefficients between the KD and the 6 other concussion assessments in isolation were determined. Assessments with ρ magnitude >0.1 were included in a multivariate linear regression analysis to evaluate their relative association with the KD.

RESULTS

Scores for SAC concentration, ImPACT visual motor speed, and ImPACT reaction time were correlated with the KD (ρ = -0.216, -0.276, and 0.164, respectively) and were thus included in the regression model, which explained 16.8% of the variance in baseline KD time (P < .001, Cohen f² = 0.20). Better SAC concentration score (β = -.174, P < .001), ImPACT visual motor speed (β = -.205, P < .001), and ImPACT reaction time (β = .056, P = .020) were associated with faster baseline KD performance, but the effect sizes were small.

CONCLUSIONS

Better performance on cognitive measures involving concentration, visual motor speed, and reaction time was weakly associated with better baseline KD performance. Symptoms, psychological distress, balance, and vestibular-oculomotor provocation were unrelated to KD performance at baseline. The findings indicate limited overlap at baseline among the CARE SRC assessments and the KD.